If you have, or know of, an Amateur Radio related site worth visiting, email me with the details to andy@vhfcomm.co.uk and I will take a look with a view to including a link - this will only be on the understanding that a link is provided from that site to here of course. Each site URL is given along with a link to that site. 73s Andy

Links published in VHF Communications magazine 3/2000 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2000 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2001 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2001 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2001 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2001 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2002 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2002 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2002 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2002 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2003 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2003 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2003 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2003 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2004 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2004 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2004 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2004 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2005 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2005 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2005 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2005 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2006 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2006 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2006 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2006 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2007 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 2/2007 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 3/2007 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 4/2007 in the Internet Treasure Trove article by Gunthard Kraus.

Links published in VHF Communications magazine 1/2008 in the Internet Treasure Trove article by Gunthard Kraus.

Ham Radio Community Chapter

HAM RADIO MODS
HAM RADIO RESOURCES
HAM RADIO REVIEWS

URL: http://www.qsl.net/kd4sai A place for amateur radio operators to learn more about the ham raido hobby, share photos, news, audio and video interactive, ham radio webcam, radio mods, solar updates, special events and ham chat. Great for all ages beginners, and experts.

CQ Magazine - Amateur Radio Magazine

The CQ-Magazine site

ATV Magazine - Amateur Television Quarterly Magazine

The ATVQ Magazine site

Communications Quarterly - Radio Communications Magazine

The Communications Quarterly Magazine site

UKSMG - UK Six Metre Group

UK Six Metre Group

Prinz Modultechnik - R.F. Components + Systems

Prinz Modultechnik A range of linear amplifiers for the Radio Amateur from 1 - 10 Ghz and 1 to 160 watts

A.D.R.I 38

Association Departmentale Des Radioamateurs De L'isere - F5KGA a French Radio Amateur site

Popular Communications - Radio Communications Magazine

The Popular Communications Magazine site

Roy Clarke's Amateur Radio, etc., site

Roy Clarke's Site 

The DX Hound site - loads of info for DX Hunters.

DXHound

The Spanish Radio and CB Site

RADIONOTICIAS

http://www.waadca.asn.au

The WESTERN AUSTRALIAN AMATEUR DIGITAL COMMUNICATION ASSOCIATION page - the group's site giving loads of info on the Australian data scene.

http://www.ultranet.com/~sstv

The JOHN LANGNER SSTV HANDBOOK page - giving all the information on standards, equipment, operating, etc., in fact all you need to know about SSTV from one of the acknowledged experts.

http://www.batc.org

The BRITISH AMATEUR TELEVISION CLUB site, where you can get all the information you need about the Club, how to join, the journal CQ-TV and amateur television in general.

http://www.scit.wlv.ac.uk/vhfc/

The RSGB VHF COMMITTEE site, where you can get all the information you need about the Committee with links to the RSGB Web pages. Lots of info about VHF and up, with links to other related sites..

http://www.algonet.se/~waveline/

The WAVELINE COMMUNICATION site in Sweden. The internet site for the Satellite Communication Enthusiast. Lots of information on satellite communication with descriptions of specialist units available from Waveline. Lots of links to satellite oriented sites.

http://www.blacksheep.org

The BLACKSHEEP CONTEST GROUP site. This is a great site if you are an active contester. Included here are the results of the RSGB VHF contests.

http://www.qrz.com/cgi-bin/webcall

The WEB BASED CALL BOOK - QRZ information on-line. You have to enter your own details to gain access to the site, but once entered access is always available.

http://user.itl.net/~equinox

The WEATHER & SOLAR INFO site is just that and much more. Loads of information on all sorts of amateur radio modes and topics. Lots of links to other useful sites. A visit is a must!

http://www.iol.ie/~okanep/

The SUPER-DUPER VHF LOG site is where the much acclaimed Super-Duper Contest Log software is available. This logging package is the only one that allows tracking of any combination of county, country and locator square multpliers in UK VHF contests. It is freely available, by anonymous ftp, as fully working unresticted shareware, from ftp.iol.ie in the /users/okanep diectrory as sdv.zip.

http://uhavax.hartford.edu/newsvhf

The NORTH EAST WEAK SIGNAL VHF GROUP site has a wealth of information regarding the group and VHF activities in the north east of the USA.

http://www.netlink.co.uk/users/hrt/

The HAM RADIO TODAY magazine site. Full of all sorts of information, HRT special offers and links to other amateur radio sites. Well worth a visit.

http://www.csz.com/sarrio.html

The HAM RADIO ON-LINE DISCOUNT CATALOGUE site is a USA based discount Ham Radio store offering a large range of equipment. A regularly updated on-line opinion poll is also conducted at this site.

http://www.innotts.co.uk/~asperges/

The G4NJH SITE which has lots of amateur radio related information.

http://ourworld.compuserve.com/homepages/drcp

The D.R.COMPUTER PRODUCTS site, where information on their range of computer-based amateur radio kits can be obtained.

http://www.logprobe.com

The web site of Carl G Lotstrom, there is quite a lot of useful information, including details of a log probe for use up to 600 MHz and a page of small projects that Carl has documented.

http://www.tonnesoftware.com

Elsie, a pasive filter design program from Jim Tonne, WB6BLD

Internet Treasure Trove article links from VHF Communications 3/2000

SYNERGY

Address: http://www.synergymwave.com

Amazon

Address: http://www.amazon.de

There is also a US store - http://www.amazon.com and an English store – http://www.amazon.co.uk

Focus

Address: http://www.focus-microwaves.com

Digital Signal Processing

http://www.mrccos.com

HAMVIEW and SPECTRAN

NARDA

Address: http://www.nardamicrowave.com/east/support/software.html

MICROMETRICS

Address: http://www.micrometrics.com

TRANSTECH

Address: http://www.trans-techinc.com

Internet Treasure Trove article links from VHF Communications 4/2000

AGILENT

Anyone who has recently been searching the Hewlett-Packard homepage for data sheets, application notes, S-Parameter files or PSPICE models will have been bewildered. These things have suddenly disappeared without trace and no clues to be found as to where they’ve gone!

There is a very simple reason for this, it is currently fashionable to split relatively large companies up into smaller parts and make them into independent entities, naturally with new names!. So we also have to make the corresponding move in this case.

New address: http://www.agilent.com

ANRITSU

Address. http://www.anritsu.com

List of German electronic shops on the INTERNET

ZRS

Address: http://www.hamradio.si/hid.html

Active Filter

Address: http://www.remcom.com

Internet Treasure Trove article links from VHF Communications 1/2001

Ansoft

A change is becoming apparent in the sales philosophy of producers of HF and microwave CAD software. Up until now, free test versions have been on offer which either operated for only a limited time (usually 10 to 30 days) or restricted performance to such an extent that even testing the product was just no fun at all. But now there has been a sudden increase in the number of student versions, which are certainly still restricted with regard to their power but now make it possible to handle more demanding projects. Ansoft have also changed their views and have put a free student version of Ensemble on the Internet. This name conceals the well-known microwave simulation program Harmonica and the system-planning program Explorer. One excellent feature is that before downloading you are given a precise list of the extent of the restrictions introduced and of their locations and you can still download 75 megabytes ...

address: http://www.ansoft.com

IrfanView32

What PC user hasn’t come across the problem of a graphics file which the systems on his / her computer can’t open? This loophole has now been closed by IrfanView32. With this new freeware you can now open and convert any – and I really mean any – graphics in even the craziest formats. One further detail is that you can also use it to set up a slide show. So we should all have this useful software handy on our PC’s.

Maury

A well-known name, famous as manufacturers of high-quality and expensive microwave test rigs. It’s always worth visiting this homepage for, in addition to data sheets for all their equipment, you can also find some very carefully written application notes. They not only describe the precise applications for the equipment in connection with the most frequent measurement tasks, but they also lay out the theoretical principles involved once more and present them clearly – something users can always profit from. We can particularly recommend the two introductory brochures covering the measurement of intermodulation and noise.

Address: http://www.maurymw.com

JFW

Anyone looking for a manufacturer of attenuators and switches of all sizes for the microwave range should download the entire catalogue of this company (over 150 pages) from their homepage in pdf format . In addition to basic introductory information, there is an enormous range of products available there, and you’ll undoubtedly find something to solve your problem.

Address: http://www.jfwindustries.com

Test & Measurement World

The homepage of this technical review has an interesting Article Archive, which you can access through the search function in the usual way. There are also some publications on HF and microwave technology in html or pdf format ready for downloading. This service is free and it’s always worth going back from time to time to see what’s new.

Address: http://www.tmworld.com/index.htm

dB

Everyone knows this measurement unit and so it’s no surprise that a company should have chosen it as its name. Here you can find microwave amplifiers and oscillators for sale and, as is so often the case, there is also some good technical information available on the homepage.

Address: http://www.microwavedB.com

EZNEC

The mist is slowly clearing away with regard to short-wave and VHF aerial simulation, and it has now become very clear what’s worth buying or testing. Anyone going into aerial simulation programs in more depth will know that all sophisticated software uses the codes from NEC2 and / or NEC3 as the core for the simulation. NEC4 is expensive perfection, which can be used even for simulation in the near field and close to the ground. But it is very expensive and moreover it is still an American military secret.

Address: http://www.eznec.com

Internet Treasure Trove article links from VHF Communications 2/2001

Synergy

The well-known manufacturer of radio-frequency and microwave components has expanded its product range and (as usual) posted the associated documents on its homepage. Of special interest here are some very well put together short tutorials (in PDF format, ready for download) on the subjects of couplers / modulators and demodulators / mixers / synthesizers / VCO / power dividers.

Address: http://www.synergymwave.com

Trompeter

This firm’s homepage offers comprehensive information on radio-frequency plugs and sockets. In addition to catalogues and application notes, there is also an interesting publication. For radio-frequency circuit developers in particular, this publication is indispensable, as it includes all the tricks and tips required with regard to the subject of radio-frequency printed circuit board drafting and the correct ways to connect plugs or sockets with a printed circuit board:

Address: http://www.trompeter.com

Philips

Anyone who has not visited the Philips homepage for some time will be pleasantly surprised, not only is the presentation now very good and user-friendly, but the number of prepared application notes has risen to well above 400. There is now 35 megabytes of information of interest to radio-frequency engineers.
The data referring to RF power amplifiers have multiplied at great speed. Something very recently added is information on such topics as circulators or electro-magnetic compatibility. However, we should explain how to get to where you want to go, for as so often a little game of hide-and-seek takes place:

Address: http://www.philips.com

Sonnet Lite / Dr. Mühlhaus

The German agent for Sonnet single-sideband modulation simulation software (for precise information on using the free test version Sonnet Lite, see VHF Communications 2/2001, Page 66) is very active, and has prepared supplementary programs on his homepage to be downloaded free. He has written some of these himself.
His "Sonnet tips and tricks" are very useful, as is the "geo3D" program for the three-dimensional representation of the simulated structure. Just as important is "dconvert" for generating "S-Parameter-Files in Touchstone format" (*.S1P or *.S2P) from the simulation result, etc..

Address: http://www.muehlhaus.com

Obtaining driver software

You have a new PC and you want to carry on using the hardware you’re used to as well. So you soon find yourself faced with the problem that (in the main) existing drivers often do not run on the new machine, because it has more up-to-date operating systems; so you are in urgent need of updated drivers for the new installation.
Where can you get the new drivers you need in a hurry? The address below is the most important one in this context, and you can find practically everything you need concerning current software and suitable links there.

Address: http://www.heise.de/ct

Meteosat / Eumetsat

Have you heard? The next generation of Meteosat weather satellites (MSG = Meteosat Second Generation) is on the starting line. The first rocket was due to be launched in October 2000, but this has been postponed until July 2001. So there’s still enough time left for anyone who is interested to become familiar with the history of Meteosat, the current technology, the transmission technology for the newcomers (almost everything has finally become digital...) or with all aspects of applications in meteorology or geography. You can also download extremely high-quality material by the ton, most of which comes under the headings of "Technical & Scientific Literature" or "MSG" . Those not wishing to go into the subject so deeply can improve their knowledge now and then by looking at the on-line house magazine "Image".

Address: http://www.eumetsat.de

National Semiconductors

No doubt with an eye to the ever-growing mobile phone market, this company has set up its own web site for "wireless communication". With regard to the product range, the greatest interest is aroused by PLL’s and synthesiser tuning. So we not only find very good and comprehensive application notes and introductions here, but also software for the easy calculations of appropriate circuits (Name: EasyPLL).

Address: http://www.wireless.national.com

Dayton Hamvention

The best-known American amateur radio exhibition has its own homepage. In live sound: The greatest Amateur Radio Convention in the world!
Here, in addition to the date of the next show in 2001, which lasts for more than one day (18^th. – 20^th. May), you can find everything worth knowing about flights, accommodation, and even the entry prices.
A photo gallery conveys an impression of the gigantic event with its halls, the arena and the unusually extensive flea market within the exhibition space.

Address: http://www.hamvention.org

Internet Treasure Trove article links from VHF Communications 3/2001

Aplac

Up in the far North, the Finns have been continually developing and improving their simulation program, and now we have version 7.6. We have already pointed out that the student version can be downloaded, together with all the documentation and manuals, from the APLAC homepage. However, if you send an E-mail and ask for the test CD, you will also receive some publicity material and a very useful application note. "Using APLAC to simulate RFIC Mixers". Taking a closer look at a decidedly interesting product, we find that, not only can it simulate the standard IP point measurement with several sounds, but it even has a chapter headed "Measuring Non-Linear Noise".

Address: http://www.aplac.com

Stellex

Anyone who has anything to do with mixers, needs an SMD version quickly, or just wants information on the most recent state of the art, should just take a glance at the Stellex homepage.

Address: http://www.stellexms.com

Sawtek

For anyone who does not yet know Sawtek: according to its own publicity, it is the right contact for anyone interested in SAW filters (surface acoustic wave filters) for all possible applications. Mostly SAW filters for the radio and mobile phone markets, and naturally in SMD formats as well. There’s always some interesting information here, which you can download as the most recent "Product Brochure".

Address: http://www.sawtek.com

Ansoft Ensemble

After "Harmonica", the well-known microwave circuit simulation program, Ansoft has now also put a student version of its EM simulator, "Ensemble" on the Internet for testing. This can be used to analyse well-known structures such as couplers, microstrips, patch antennas, etc..

Address: http://www.ansoft.com

Note: Such well-known products as Sonnet, APLAC, etc. are now competing with one another for the "student version market".

Yet, of course, we do not know whether all products are equally good, fast, reliable or precise. You can only test this yourself by using the different programs on a fully completed project (e.g. a patch antenna).

Microwave Journal

The well-known trade journal has taken the trouble to post the technical articles from back numbers going back to the middle of 1997 on its homepage as the "Editorial Archive" – a fantastic treasure trove.

Address: http://www.mwjournal.com

RLC

If you want to use coaxial switches in SMD format (e.g. SPDT type = single pole / double through) in your development work, you could well just take a look at this company’s site. The frequency range on offer goes from DC up to 26 GHz, but there are also couplers, dividers, terminations, attenuators, DC blocks, BIAS tees, detectors, etc..

Address: http://www.rlcelectronics.com

Internet Treasure Trove article links from VHF Communications 4/2001

SONNET Lite 7.0

The manufacturer of the well-known EM simulator, which has already been introduced here in Part 1 of the article on modern designs for patch antennas, has improved the free "Lite Version". SonnetLite 7.0 now offers expanded simulation options. Thus, for example, there are now more ports available, the online help has been rewritten, pared-down algorithms allow more extensive simulations to be carried out with the same main memory restrictions as previously, etc..

In addition, a version is now on sale with max. 32 MB main memory, but for $ 500.

Address: http://www.sonnetusa.com

Applied Microwave and Wireless

The well-known American technical revue has now archived almost all technical articles up to 1989 – like the "Microwave Journal" – and they can be accessed through the homepage. Some highly interesting subjects are covered, although even here the conspicuous copyright stamp must be respected, including the ban on reproduction. Copies of material can be obtained without charge following registration.

Address: http://www.amwireless.com

MINI-CIRCUITS

A well-known name for a very wide range of HF and microwave components (couplers, mixers, amplifier components, dividers, attenuators, etc.....). It’s worth visiting their homepage, as there you will find not only numerous documents for downloading but also an endless succession of new ideas. The most recent products are passive mixers with fabulous IP3 values going up to +38 dBm, or the interesting and reasonably priced "Bluecell Mixer".

Address: http://www.minicircuits.com

APLAC

The Finns in the far North are also hard at work: now APLAC 7.61 rolls up as a free student version with the usual advance publicity and improvements.
The offer of a 45-day full test version is very advantageous. As soon as you are actually up to speed with the student version and are coming up against restrictions in using it, due to the size of the project you’re tackling, you apply for a license and continue to work on the problem with the full version. Although the computer used must form part of a network!

Address: http://www.aplac.com

PCAAD40

If this heading sounds somehow familiar, there’s a good reason why: version 2.1 was recently introduced in VHF Communications in the section entitled "An interesting program".
The author, David Pozar (who has also been responsible for some very good technical books on microwave techniques) has developed the program quite considerably. There is now a large WINDOWS 32-bit version, with over 30 different models of antennas alone for investigation and analysis. Unfortunately though, it is no longer free, but costs $ 390.

Address:
http://www.antennadesignassociates.com

VECTRON

A manufacturer which has specialised in SAW filters, and particularly in crystals and crystal oscillators of all kinds (TCXOs, VCXOs, OCXOs, etc...) for all conceivable frequencies.

Address:
http://www.vectron.com

TACTRON

This firm has for years been a supplier of American microwave components and simulation software such as the MICROWAVE OFFICE, etc.
On the homepage you can naturally find documents covering the complete product range, but there are also some very interesting new items:

Address:
http://www.tactron.de/mytactron

ARCOM

Anyone wanting to become more closely acquainted with dwarf wave techniques will find a manufacturer of power amplifiers, low noise amplifiers, down and up converters, transmitters and receivers here. Not only is it interesting to glance at the many data sheets available, but it is also worth keeping an eye on the new "Education Page". This is intended to become a forum in which like-minded people can exchange and extend their knowledge.

Address:
http://www.arcom-inc.com

IONBEAMMILLING

You read it right: not only is that the firm’s name, but they "really do carry out milling with ion beams".
Here all possible microwave and millimetre structures (couplers, attenuators, filters, etc.) are marked out, for example on gold-coated ceramic plates, using the "atomic sand blasting process" (actual quotation from firm!). The way the procedure works is also precisely described. Truly the most modern high-tech manufacture - genuine information for those interested.

Address:
http://www.ionbeammilling.com

Internet Treasure Trove article links from VHF Communications 1/2002

Stanford Microdevices / Sirenza Microdevices

Here you have to make a quick re-adjustment, the well known firm of Stanford has suddenly changed its name. Nevertheless, its activities remain unchanged. They still make new low noise amplifiers, mixers, gain blocks, etc for the frequency range between 0 and 10GHz.

Address:

http://www.stanfordmicro.com

Flex-PDE

The Internet has some new EM simulation software, known as "Flex-PDE" for 2D and 3D analyses in the microwave range. This is especially suitable for the extremely high frequency range between 10 and 100GHz. Those interested can download the free test version.

Address:

http://www.pdesolutions.com

Linmic

Again, something similar, but centring on what is (according to the publicity) a combination of EM simulators and layout orientated CAD software packages which is unique in the world. Here too there is a demo version for testing.

http://www.linmic.com

Here you can, find out all about microwave diodes, i.e. Schottky diodes, PIN diodes, tunnel diodes, varactor diodes, etc. Naturally, there are also comprehensive catalogues, data sheets and application notes.

http://www.metelics.com

Marki Microwave

Never heard of them? Well, anyone who’s looking for fast doublers, mixers, multipliers or converters at reasonable prices for the frequency range between 0 and 40GHz in SMD format should take a glance at this page.

http://www.MarkiMicrowave.com

Rf Nitro

This site has nothing to do with artificial fertilisers or explosives. It deals with the cutting edge of MMIC development in GaA’s or GaN technology. A wide range of products for the microwave range and some excellent application notes practically compel you to visit this site.

http://www.nitro.com

National Instruments

A company manufacturing and marketing measurement technology hardware and software on such a large scale (think of "LabView", for example) is naturally a real Treasure Trove for those with relevant interests. Here we find not only data sheets and test software CD’s but also separate document packages for users and developers. Also on offer are tutorials on various subjects and product groups.

http://www.ni.com

Internet Treasure Trove article links from VHF Communications 2/2002

KACHINA

Here, among other things, we can find a set of wiring diagrams for the Transceiver 505DSP, which is no longer manufactured. (Obviously you can still obtain residual stocks of this transceiver at favourable prices.) You can also look at some application reports. Address:

http://www.kachina-az.com

Synergy

The well known microwave component manufacturer has made a really big effort once again and has completely revised its homepage. So now under a specific heading we find not only data sheets but also appropriate application notes, technical documentation and technical articles (from periodicals). Treasure Trove indeed!

http://www.synergymwave.com

NEC Archive

The website of Ray Anderson, WB6TPU, contains an NEC archive; here, among other things, you can download the Yagi design program YGO3.ZIP, this is also available from the VHF Communications web site.

Analog Devices

A big name in the field of IC production, mainly active in analogue circuits, D/A converters, RF-ICs, etc. and also in digital signal processors. The technical documentation has been greatly expanded, and especially the basic tutorials (e. g. on digital signal processors). You can look around for hours now and find more and more new stuff to downlowad.

http://www.analog.com

Software Radios

Under the precise address given below:

The Longwave Homepage

Amateur activities in the longwave area are a really new challenge for do-it-yourselfers and for anyone who enjoys fiddling about. And it was only a matter of time until like minded people met up and got organised on the Internet as well. This homepage is the first address anyone interested in longwave reception should visit, as here you can find the technical equipment for getting started, both theoretically and practically. And naturally there are lots of links to similar sites or interesting documents.

Internet Treasure Trove article links from VHF Communications 3/2002

Agilent

Following the change of name and the re-organisation of the company (formerly Hewlett Packard), calm is slowly returning to the homepage as well, together with the quality that we were used to. So it’s worthwhile taking another trip through the various areas on display, and in particular having a look at "Semiconductors/RF and Microwave", where all the previous application notes are back with a new look together with some genuinely new items.

http://www.agilent.com

 Texas Instruments / Burr Brown

The sector’s giant and the inventor of TTL technology has made a discovery. High quality analogue technology is also important, and has a big future in connection with modern digital signal processing. So it’s not a question of re-inventing the wheel, it’s more that a well-known and worthy representative of the analogue branch has simply bought it up. So we also find the former Burr-Brown application notes here in the TI homepage in downloadable form.

http://www.ti.com

The earlier DOS program package from the good old HP days can now be obtained free of charge once again in the most recent Windows version from the successor company (Agilent) and can be downloaded from the Internet.

http://www.hp.woodshot.com

 Alpha Industries

This is an important address for all types of microwave semiconductors. The "millimeter wave squad", in particular, will not only rejoice over the circuits on offer for applications from 20GHz upwards, but will also treasure the data sheets and application notes prepared. What is also really great and very informative is that a whole collection of splendidly crafted complete circuit diagrams of modern transmitters, receivers, etc. can be fetched onto your own computer. Even diagrams and formularies are available as aids to development.

http://www.alphaind.com

 DSP Guide For Scientists And Engineers

A specialist volume more than 600 pages long, excellently produced from both the technical and educational points of view, and dealing with digital signal processing, that wouldn’t be cheap, would it? And yet it can be, if you take the trouble to download all 33 chapters from the PDF files individually, free of charge from the author’s homepage. It does take some time to transfer 20 megabytes, but that isn’t the problem. Every time you download a chapter, the humorous author makes comments such as: "Do you really expect your laser printer to do this?" or "I think now it’s easier for you to buy the hardback edition", etc..

http://www.dspguide.com

 Linear Technology

Another specialist in analogue circuits: from operational amplifiers through AD converters, right through to switch regulators for power supplies.

http://www.linear-tech.com

 RFMD (RF Micro Devices)

Another well-known manufacturer of standard microwave components, producing everything needed for circuit development from amplifiers or mixers through the front end right to the attenuator or the switch MMIC. Support is exemplary once again, in the form of many data sheets and technical notes that are available free of charge from the homepage.

http://www.rfmd.com

GraphTrack

The GraphTrack program, formerly marketed by Silicon Solutions, is available in an updated version for the MTI interface for satellite rotors.

Address:

http://www.rcallen.com

Internet Treasure Trove article links from VHF Communications 4/2002

PUFF and LINUX

It’s taken a long time and more and more people have been asking for it. The homepage referred to below finally provides an adaptation program for operating the much-loved microwave CAD program Puff using Linux.

http://wwwhome.cs.utwente.nl/~ ptdeboer/ham/puff.html

Applied Radio Labs

This is a company in Australia that specialises in the problem area associated with VCO, PLL and noise. Thus we find here the "SimPLL" program for the design, optimising and simulation of PLL synthesisers. The program can be downloaded free. Of still greater interest are the basic articles on these subjects in the on-line tutorial, which you really should look at – very well put together and easy to understand, in particular the sections on the basic facts about noise or sideband noise.

http://www.radiolab.com.au

Amateur Radio Download Page

There must certainly be a lot of these on the Internet, but this page offers a good mixture for various applications. Thus we find the following areas represented here:

• Legislation and regulations concerning amateur radio
• Low-frequency decoder
• Sat programs
• DSP applications
• Telex and packet radio programs
• Morse practise programs
• Weather satellite image evaluation
• Log book programs
• Locator programs
• Collected test questions, etc.

http://www.qsl.net/df0che/dwn.htm

FAISYN

The proven DOS filter calculation program, available for years, now has a Windows successor. It’s easy to operate, a good, precise program, and it has the usual modern printing options. It comes over as a worthy representative of its name. However, the program must be either deleted or registered after a 30-day test period. Unfortunately, you then have to pay $99...

http://members.aol.com/faisyn/faisyn.htm

Technical University Of Munich

The Electro-Technical Institute has collected some interesting things that can be downloaded from its RF section. We don’t merely find collections of formulae and nomograms for all possible areas of high-frequency engineering here. This homepage is also very important as a source of diagrams with, in particular, the current limiting values for the electrical and magnetic field strengths of signals.

http://www.hfs.ei.tum.de

MSTRIP40

The title story in issue 2/2002 of VHF Communications dealt with this free EM simulator, and there are some good new features here. Professor Splitt has now posted the unrestricted full version on his homepage to be downloaded. The program makes it possible to simulate structures with a maximum of 5 layers.

http://www.intek.e-technik.th-kiel.de/splitt.htm

Microwave Engineering

This is one of those typically American technical reviews (similar to "Microwave Journal") with a motley assortment of advertising, situations vacant and technical articles, which can be obtained free of charge following registration. There are also sections such as "News" or "Features", which represent outstanding sources of information for the specialist. And you can also search the archives of previous issues.

http://www.gaasnet.com

Internet Treasure Trove article links from VHF Communications 1/2003

Antenna Design Calculator

Anyone who visits the homepage of "Q-Par Angus" in England is entering a forest of microwave antennas. Innumerable microwave antenna types, going up to 100GHz, are designed, manufactured and marketed there, and naturally there are detailed descriptions as well. There’s certainly a lot of useful information available here.

Address:
http://www.q-par.com

AppCad , Version 3.0

This is brand new, the most recent Windows version of the "Personal Design Assistant for RF, microwave and wireless applications". A very long time ago, when Agilent was still called Hewlett Packard, this program existed on a 5 ¼ inch diskette. This ancient version can also still be downloaded, but it won’t work properly except with pure DOS. On the plus side, it still contains some things that were deleted later such as spiral inductor design, etc.

Address:
http://www.hp.woodshot.com

Radio Waves below 22kHz

Have you heard of Schumann resonances? Or can you sketch a Whistler receiver? If you want to close such gaps in your education, just pay a visit to this Italian homepage. It can be described as compulsory reading for those people who want to get involved with the interesting area of VLF, ULF or ELF. Anyone landing up here will find innumerable recommended links to follow.

Address:
http://www.vlf.it

Transmitter Tour

What would it be like, just for a change, to go on a technical tour through various radio stations such as "Voice of America" etc. To savour the technical details of such high powered transmitters, as revealed in many illustrations and detailed explanations? Then just go to "Jim Hawkin’s Radio and Technology Page". The author has assembled more than 300 photos, and there’s also plenty of material on the history of wireless transmission technology. Naturally, there are also sub menus and links for such modern subjects as DAB, etc. Extremely entertaining and never boring! If you want to learn a bit about the principles, then just enjoy "Electromagnetic Radiation explained"

Address:
http://hawkins.pair.com/radio.shtml

A Site for the practising RF engineer

That’s what our next site’s called. A lot of stuff has been assembled here that people need more and more frequently. Two very fine and well produced features are the tutorials on direct conversion receivers and fractional N synthesisers. But there is also a complete page containing nothing but links to companies who offer application notes for downloading. Another important thing, here you can finally download the standards for the various modern communications systems such as GSM, 2G, GPRS, WLAN, WDCDMA etc. onto your own computer.

Address:
http://www.rfengineer.cc/

RF-WEB

As down-to-earth as the name implies. A very comprehensive but very unimpressive site greets you, containing nothing but links to interesting aspects of radio frequency technology. But if you take a closer look at this list, then you will very soon be mentally begging the author’s pardon, because not only is there an unbelievable amount available here, but it’s a real Treasure Trove.

Address:
http://www.rfweb.com

Online Education

Internet learning is continually on the increase, in our specialist subject as well, so we’re giving two interesting links for better information here. The material available there is not intended for immediate downloading but for on screen training and/or further education. Professors, teachers and specialists have created the splendid lessons or learning packages, which makes for willing pupils. You’ll have no trouble getting stuck in here, so to speak.

Address 2:
http://www.iec.org/online/tutorials

RF-Cafe

This, as you might expect, is a site where you just sit back and have a good old rummage around. You will undoubtedly know of, or you’ll already have, a lot of the literature or software mentioned here, but the author never sits still and is always on the lookout for interesting new items (such as a waveguide filter designer).

Address:
http://www.rfcafe.com

Internet Treasure Trove article links from VHF Communications 2/2003

Ansoft

The free download site of the well known supplier of simulation tools has expanded yet again. In addition to the student versions of Serenade SV (High frequency circuit design) and Ensemble (Wireless circuits and planar antennas), we now also have "Simplorer" (Multi-Technolgy Simulation for automotive, aerospace and power design). And the very latest thing is "Maxwell SV", an electromagnetic field simulator. These are stripped down versions of the professional tools written for Windows NT and cannot be guaranteed to operate satisfactorily with Windows ME or XP.

Address:
http://www.ansoft.com

Rogers Corporation

The manufacturer of RT-Duroid and other printed circuit board materials making its very comprehensive range available, together with all conceivable technical data, in the form of pdf files. There is also a free download area containing a stripline calculator and a "Flex-Analysis" program for investigating modern printed circuit boards that can be rolled up like a cigarette with the components fitted.

Address:
http://www.rogerscorporation.com

K&L Microwave

K&L are a filter specialist who makes everything possible – well, everything guaranteed to be manufactured. From the LC filter to the bandpass wave guide filter, from the cavity filter to the duplexer, the customers can have whatever they want. The homepage includes a collection of pdf files on complete filters, also a download area, so that the filter data can be matched with suitable programs, and consequently you can have your own filters made. Of great interest, and a good test for your knowledge, are the two pages of filter definitions and filter specifications in the "Products" section. This brings together all specialist filter terminology with a clear explanations.

Address:
http://www.klmicrowave.com

Microwave Office

Another microwave simulation program, and another one that makes a free test version available for 30 days. It is probably not so interesting for the private user on grounds of cost alone, but the homepage does contain a lovely collection of application notes with many practical examples. It is worth more than a casual look and to see where the associated literature sources can be found (e.g. for hairpin filter design).

Address:
http://support.mwoffice.com/appnotes/listnote.aspx

RF Micro Devices

Manufacturers of components and IC’s for modern communications technology are probably not in an enviable position. The intervals at which the entire production range has to be almost completely shaken up and renewed have become shorter and shorter. That is true of this company too, who among others, supplies the mobile telephone, GPS and Bluetooth markets.

Address:
http://www.rfmd.com/prodTechnical.asp

Simtel

The name conceals a provider offering any amount of free software for downloading. Of particular interest for people like us is the page on "MSDOS Electrical Engineering Programs", because this contains antenna calculation programs, filter programs, EM Field Analysers and much more (and you’ll meet up with old acquaintances, such as "faisyn", "pcaad21" and "filtry"). It’s worth rummaging around a bit here

Address:
http://www.simtel.net/pub/msdos/electrcl/

UK Microwave Group

You should drop in on these guys regularly, as there’s always something new. This time it’s the free student version of the filter program "elsie", but there’s also the "Hardware" section, and don’t forget to take a glance at the "scatterpoint" magazine.

Address:
http://www.microwavers.org/index.htm

Anadigics

They are a company who manufactures every possible type of semiconductor and IC for RF and microwave applications and not only have magnificent pdf data sheets on the Internet, but also provide application notes to look at and generally rummage around in. You can also find a splendid range of items for downloading at the following address:

Address:
http://www.anadigics.com/products/appnotes.html

Data Bookshelf

If you urgently need the data sheet for some component or other and you know the manufacturer, you should keep this link handy. Here you will find the Internet addresses of practically all semiconductor manufacturers, beautifully laid out in alphabetical order. Just one click and you’re connected to the homepage of the company you want.

Address:
http://www.crhc.uiuc.edu/~dburke/databookshelf.html

LC

No, this is nothing to do with a tuned amplifier circuit or with any kind of filter circuits. We’re talking about a free EM simulator (e.g. for calculating microwave structures or patch antennas). Free up to now for users of Cray or SGI super-computers, but suddenly there is also a LINUX / Intel x86 version available for downloading following registration. There must be lots of people who’d be interested in that.

Address:
http://lc.cray.com/

FIR filter software list

Anyone who has ventured into digital signal processing must have wanted to program digital filters. This site provides a comprehensive list of FIR design software that can be downloaded or used on line. And naturally there’s an important link to other DSP pages.

Address:
http://www.poynton.com/notes/links/dsp-links.html

Micromanipulator

A small site admittedly, but a splendid one for all that. It has an outstanding list of the characteristics of standard contemporary microwave connectors, together with some good comments on correct microwave circuit metrology.

Address:
http://www.micromanipulator.com/RF-Notes.html

Internet Treasure Trove article links from VHF Communications 3/2003

Antenna tools

This is really a little treasure chest, in addition to the assembly instructions for a 137kHz receiver and many other things, there is also a special page for antenna freaks with "Antenna tools". These are Java scripts to calculate everything conceivable on line. Would you care for a little taste? "Conversion between Field strength and received power / Field regions / Isotropic losses of free space radiation / field strength, field area and received power…..etc."

Address: http://www.giangrandi.ch/jack/main.shtml

TCS Online conversion page

More of the same, with the Java scripts for rapid calculation of every possible aspect of telecommunications, but this time provided by a big company and on offer to customers or to anyone interested. Considerably more extensive than the previous link, but just as interesting.

Address: http://www.tcstx.com/conversions/online_conversions.htm

Radio Mobile

The simplest thing is just to quote, word for word, the heading and description for the freeware which can be obtained here:

Address: http://www.cplus.org/rmw/english1.html

World Wide Web Links

Any number of interesting downloads await the radio amateur who calls up this page. The site covers both databases and online tools for calculating many things (not only relating to antenna technology or to circuit engineering). Just take a peep!

Address: http://www.w4rrc.org/RARCClubWebLink/WebLinkReferenc.html

Pearl Scripts of Interactive Design Software

Somehow this is slowly becoming the fashion, interactive online calculators for telecommunications and antenna engineering, but the ambition (or the competition!) is obviously gradually becoming so intense that each wants to outdo the other. Just take a look at this page....

Address: http://www.qsl.net/n9zia/wireless/page09.html

AVX

Something different for a change. Anyone who wants to get well informed on the smallest details of RF and microwave capacitors might well want to click on this link. In addition to data sheets, spice models and software, there are well compiled and informative articles to study.

Address: http://www.avxcorp.com/SpiApps/default.asp

Spread Spectrum

Do you just want to become a bit more familiar with this area via a good tutorial or simply to find out about the basic principles? These links can give you some confidential help.

Address: http://www.ncafe.com/chris/pat2/index.html

RF Avenue

That sounds like a pleasant stroll, and that’s what this is. Mind you, it takes rather a long time and it’s a stroll around the computer, for by the time you’ve thoroughly explored this page and tried everything out, it’s long past midnight.

Address: http://www.newwaveinstruments.com/resources/rf_microwave_resources/

YDI

Please take a look yourself, as here too there is information on offer relating to what you can learn and calculate.

Address: http://www.ydi.com/calculation/

Ingecom

Here you can obtain a very well-written article entitled "VHF and UHF Antenna Design". It is really rewarding, either as a stimulus to further research or as a refresher of what you may already know.

Address: http://www.ingecom.ch/Pics/an_antenna.pdf

Holaday

This is something for people who are interested in EMF (electromagnetic field measurements), whether for professional or private reasons, in order, for example, to get to grips with the problems of risks associated with EM fields. Very good application notes and articles make it worth clicking on.

Address: http://www.emctest.com/Holaday/appnotes.htm

Antennex

And finally, another big jar to rummage around in, as here too the concept of antenna engineering is stretched a long way and includes many associated areas.

Address: http://www.antennex

Internet Treasure Trove article links from VHF Communications 4/2003

That's the heading above the lists of links and downloads on this homepage. But we're dealing with tutorials on the basic principles here, the list is never ending, and it's impossible to itemise everything there is here on this subject. So just have fun rummaging around!

Address:
http://members.fortunecity.com/ xe1bef/theory-antennas.htm

Radiometrix

A company which specialises, in particular, on data transmission and modems, including those operating over radio routes. But there are also some neat application notes for the RF freak, quite apart from the many data sheets and other information regarding interfaces.

Address:
http://www.radiometrix.com/

TX Lines, Antenna Systems, PC Joystick

We don't want to spend all our time talking about antennas, but a homepage with such good tutorials and with so many different applications deserves a mention.

Address:
http://www.tmeg.com/tutorials/tutorials.htm

Radio Waves

The site's name gives you a pretty good clue: it deals with developments and products relating to electromagnetic waves. The main theme is antenna development and the production of complete antenna arrays. And because in this kind of work you have to pay very close attention to the customer's wishes, there's also an extensive planning section. One splendidly attractive gift from these people to all RF freaks is the "RW calculator" for calculating and planning every last little thing relating to antennas and receivers, which you can download free of charge. This is really something great, with many different applications of all kinds!

Address:
http://www.radiowavesinc.com/html/414_rf_system_planning_tools.cfm

Longwave links

Just for a change, here's something in German, and something for the community of longwave fans. This homepage is a must for anyone wanting to know more about this field and this technology.

Address: http://home.t-online.de/home/hhcuno/afu/ longlink.htm

Amateur Television and high speed data signalling

Even though this homepage is hosted from France, you don't need any knowledge of French, as there is an English version. We are certainly grateful to the owner for the opportunity to download information on well documented DIY projects, going up to 2.3GHz, which will gladden the heart of any do-it-yourselfer.

Address:
http://perso.wanadoo.fr/jf.fourcadier/accueil/accueil_e.htm

G4FGQ's Software Site

An interesting page, put together in a way that's just right for the amateur and for anyone who likes fiddling about with RF projects. You can spend a lot of time here searching, investigating and downloading. Most of this site is about programs, all "home made" and all similar in appearance. So you know at once what it's all about, and you don't have to spend a long time in experimental operations. Very rewarding and highly recommended!

Address:
http://www.btinteret.com/~g4fgq.regp/#S102

W2BRI's Magnetic Loop Site and PA3CQR magnetic loop antenna page

As always on such sites, the more you nose around and the more stones you turn over, the more treasures you unearth. Very enjoyable and informative to see everything concerning loop antennas summarised here.

http://www.iri.tudelft.nl/~geurink/magnloop.htm

Alphabetically arranged radio technology links

A site like this makes it considerably easier and more comfortable to search for a program, an article or a homepage to solve a problem.

Address: http://home.wanadoo.nl/~a.schipper/fuurllinks.htm

Myer's Engineering International

23 years of experience with radio communication systems and antennas... that's what it says in the introduction to this site. Another homepage which can reveal masses of new or fascinating facts for those with an interest in such matters. Seek, and ye shall find...

Address:
http://www.myerseng

Internet Treasure Trove article links from VHF Communications 1/2004

SONNET

There’s some very important news for those using the free “Light” version of this familiar EM simulation program: the newest update gives you free access to something people have been waiting for a long time. Now you can finally connect an exciter port into the centre of the structure as well, and not just (as until now) to the wall of the metal box which is required for the simulation. So now, for example, patch antennas can also be powered directly on the patch and not just via a tiresome long supply line. That’s really a concession worth having!

Address:
http://www.sonnetusa.com

University of Ulm

And now for something completely different: here you can find the processes taking place in waveguides, couplers, circuits and filters, etc, presented in vivid animated form. And to round things off, both a demo version of the analysis program in use (TLM = Transmission Line Matrix Method) and a link relating to the animation program are available. Very informative and amusing, even as revision for people who already know everything!

Address:
http://mwt.e-technik.uni-ulm.de/lehre/hf-anim/mefisto/

Engineers Heaven

The heading for this homepage, run by a Turkish university, makes an interesting promise. Just looking at the sections on offer is a pleasure, as you contemplate the data available concerning microwave technology.

Address:
http://www.ee.bilkent.edu.tr/~microwave/magnetic.htm

EMC Technology

This website has some interesting application notes, which you can study and download, they are mainly concerned with couplers and circulators. But they also include information on the practical fitting of SMD components on microwave printed circuit boards.

Address:
http://www.emct.com/softwaretools.htm

TMEG

This is an acronym for "£The Millenium Education Group" and consequently there are some very nice tutorials. The two sections on "Transmission Lines" and "Antennas" are particularly interesting, but there is also "Babylonian Mathematics" or "an electronic needle gun". So, for anyone who’s interested .....

Address:
http://www.tmeg.com/index.html

RF Tools

Another of those homepages where you almost find yourself feeling giddy: innumerable RF tools and documents of all kinds are on show for interested users to sniff out and download. You just can’t count everything there is here. I recommend you set aside sufficient time, then just open up the site.

Address:
http://rfengineer.cc/rftools.htm

Chenjian's Electronic Packaging

Anyone looking for up-to-date information on the state of manufacturing technology, including housings for integrated RF components (amplifiers with integrated coils, capacitors and resistors, couplers, etc.) should have a look at this site. The content ranges from information on trends, technologies, production processes and opinions on reliability right through to material trials, and finally an "Online Dictionary".

Address:
http://chenjian.virtualave.net/packaging/tech/other/rf/rf.htm

Faustus

The classical touch extends beyond the company's name to its product, MEFiSTo.
This is (another...!) EM simulator, but here, for a change, the company has found a different way to awaken customers' interest. They're currently introducing the most recent version onto the market as a 3D simulator, and so they're giving away an older, fully operational "Classic 2D Version", to be downloaded free of charge. Quite an interesting move!

Address:
http://www.faustcorp.com/downloads/index.html

MURI

Or, to reveal its full title: "The Multidisciplinary University Research Initiative (MURI) for High Power, Broadband, Linear, Solid State Amplifiers at the Cornell University".

Fortunately, these friendly people do not lock their findings and their documents away in the safe but make them freely available. But clearly not without reservations, or maybe an enthusiast for memory games is in charge of the homepage! There is no index, and everything is actually hidden away behind anonymous report numbers in a huge file, and it really is like playing some game. You have to uncover and examine everything first to find out whether you can get anything out of it. Luckily, the hit rate is really excellent......

Address:
http://iiiv.tn.cornell.edu/www/schaff/muri/reports/

Jim Hardy's Homepage

For once, something from a private individual, very nice and amusingly put together. Not just links to many of our areas (it turns out the man is also a radio ham!), but also a lot of funny material. The following section is particularly worth reading: "How Things would be different if Microsoft built cars" It’s true you have to root around a bit, but it’s worth it for what you can find.

Address:
http://www.surfsouth.com/~jhardy/index.htm

Software for the Radio Amateur

Here’s another link for people who like to spend hours surfing and rooting around. Luckily, everything is listed alphabetically, and so you can carry out a targeted search.

Address:
http://www.estpak.ee/~andrew/ham/software.htm

Internet Treasure Trove article links from VHF Communications 2/2004

ANSOFT

Once there was a feature film called “The Empire Strikes Back”. That’s what I was reminded of when I downloaded the all new free of charge student version of the RF CAD “Designer” software from Ansoft (N.B.: almost 80 megabytes!). Never have so many tools been made available for simulation and for development in general. Naturally, it takes a while to familiarise yourself with the package, but it’s worth it. Virtually all areas are covered, virtually all the calculators for RF and microwave engineering are provided. However, there is unfortunately one way in which Ansoft has stayed true to its old habits. There is scarcely any documentation – in some cases, none at all – to explain what has been left out of the student version. And of course, you find this out as soon as you ask the software to solve any really complicated practical problems. But apart from this, it’s first class!

Address:

http://www.ansoft.com/

The N4UJW Antenna Design Lab

That’s exactly what this site has to offer: any amount of software and information relating to antennas and antenna calculation. And a search through the list of links unearths some interesting things. There’s something hidden behind every item on the screen.

Address:

http://www.hamuniverse.com/

RF Avenue Resources Directory

Anyone opening up this page has a few problems, as you’re initially confronted with an endless list of documents concerning RF and microwave engineering. Of course, it’s all nicely and neatly sorted out. You could spend hours here...

Address:

http://www.newwaveinstruments.com/resources/rf_microwave_resources/
 

LC

This doesn’t refer to a resonant circuit but to the firm of LaCray – who are well known for their extremely fast mainframe computer. It’s no surprise that people use such expensive equipment mainly for complicated EM simulations of expensive antennas. But it’s not exactly obvious why the company is now allowing people to download the “LC” EM simulator used for this purpose at no charge. Certainly the computer you use should be a Cray computer, but a Linux version is kindly provided for those possessing Intelx86. Do feel free to nose around on your own. It’s really very interesting.

Address:

http://lc.cray.com/

Marska WLAN Pages

Even up in Finland there are some active people, which is why it’s worth rummaging around on this homepage. One very interesting subject is what you can find here under the heading “2.4 GHz WLAN antenna – Do it yourself”. You can choose between English or Finnish texts. But anyone who doesn’t speak any Finnish will have given up already during the search, and will not be looking for it any longer.

Address:

http://www.saunalahti.fi/elepal/antennit.html

USMICROWAVES

This manufacturer describes itself as a “manufacturer of MIC thin film technology” That means it’s a source of unending interest for those who want to be comprehensively informed concerning the state of the art in relation to all types of these active and passive microwave components. In addition to the data, layout design rules and/or application notes, etc. are also available in all sections.

Address:

http://www.usmicrowaves.com/

Semiconductor Datasheets on the WEB

This is a page full of pleasant surprises for original developers and anyone who likes messing around, as everything here is nicely and neatly alphabetically sorted and  frequently provided with links.

Addresses:

http://www.bgs.nu/sdw/

Radio Netherland

Just for a change, not pure technology, but tips and technology concerning the subject of  “Long-distance reception on the medium wave and short wave”.  Plus a collection of facts relating to the relevant antennas.

Address:

http://www.rnw.nl/realradio/practical/html/longdistancemw.html

Microwave Active Antenna Group

This site (which is run by the University of Colorado) is also guaranteed not to be boring, for the students are very active and post their well documented research results on the homepage.

Address:

http://nemes.colorado.edu/microwave/theses.html

Free Radio and Computer Programs

What makes this such a fascinating site is that you can just call up one program after another to see whether you might need them. The choice is wide, and there’s certainly enough here to be going on with...

Address:

http://www.btinternet.com/~g4fgq.regp/index.html#S102

Vectron

All about crystals - that’s the motto here. Follow the links listed to find the application notes which cover every conceivable aspect of this subject.

Address:

http://www.otek.com/products/appnotes/index.htm

Estland Amateur Group

How about a trip to see the real Northern Lights in Estonia? Here you will discover that progress and hi-tech have penetrated almost as far as the Arctic Circle. Some very interesting links and articles!

Address:

http://www.estpak.ee/~andrew/ham/ha,htm

QRZ.COM

Fertile ground for all radio enthusiasts. Here too, you can rummage around endlessly among programs and technical documents...

Address:

http://www.qrz.com/download/main/index.html

Dxing.Info

Another site to rummage around and browse in – everything you could need in relation to physics, technology and equipment know-how for DX reception.

Address:

http://www.dxing.info/

WAOTRALI

This is an animation program (Waves on Transmission Lines) from the Flensburg Technical College. It can help to clarify the propagation of signals on lines in the time domain. Various transmission signals can be selected from a catalogue, such as sinusoidal signals and pseudo-statistical digital signals of various lengths, among others. The WAOTRALI program is available for downloading from the website of the Institute for Communications Technology of the Flensburg Technical College.

Address:

under www.fh-flensburg.de/kt/

Internet Treasure Trove article links from VHF Communications 3/2004

MACOM

Microwave and millimetre wave IC products...that’s what it says in the publicity. A very nice homepage, recently revised, done by someone I know well. In addition to comprehensive data sheets and basic information, you can also find some interesting new application notes here.

Address:
http://www.macom.com/tech_app_resources/techapp_app_note.jsp?i=0

PENTEK

Technical development marches on – and that includes receiver technology too. Digital receivers, loosely referred to as “software radio”, are in the vanguard. Anyone wishing to read up on this new technology and get some idea of the concepts involved might like to download the “Digital Receiver Handbook” from Pentek. The principles, characteristics and advantages of this new technology are very nicely explained here – and, best of all, direct comparisons are made with standard analogue receiver technology.

If you explore the homepage in a little more detail and download the company’s main catalogue onto your home computer, you’ll get another surprise. Chapter 2 includes a very interesting collection of miscellaneous tutorials dealing with this area!

Address:
http://www.pentek.com/sftradcentral/Overview.cfm

Software Radio Resource Page

Something else on this subject in the form of every possible link which is relevant to it. Once you really get into it, you’ll soon lose track of the time...

Address:
http://www-sop.inria.fr/rodeo/personnel/Thierry.Turletti/SoftwareRadio.html

SYNERGY

An old acquaintance that supplies every possible type of microwave module. The homepage has been re-designed and, most importantly, there is now a much wider range of articles and application notes. Of particular interest is the documentation on offer in relation to synthesisers and microwave oscillators.

Address:
http://www.synergymwave.com/Articles/Articles.htm

Amateur Radio Soundblaster Software Collection

This homepage, which is run by Dr. Oliver Welp (DL9QJ), deals with the use of the PC sound card for all possible purposes and operating modes in amateur radio. A very comprehensive collection, especially the enormous number of links to other pages and topics.

Address:
http://www.muenster.de/~welp/sb.htm#analyzer

Electronics for physicists

The University of Kiel is behind this site, and it’s really great how teaching materials are designed and prepared nowadays. In particular, you should just take a look at the topics that cover our own area (AM, FM etc.). But there’s some interesting new stuff here even for specialists  — just call up subjects like “Types of Modulation” or “Noise and Noise Suppression”. I guarantee that you won’t be bored.

Address:
http://www.ieap.uni-kiel.de/plasma/ag-piel/elektronik/

Downconverter page

It’s both amusing and comforting when you come across sites run by other “mad D.I.Y. people”. Steve Blackmore has a day job as an electronics specialist, but it clearly doesn’t take up all his energy. So he goes in for decoding digital transmissions in a big way. He has generously made available his experience in relation to weather satellite reception, and you should work your way through all the cross-references of his homepage, where you’ll find all sorts of interesting things. Here’s a tip: there’s also a page (it’s a bit hard to find) that deals with quadrifilar helix antennas.

Address:
http://www.pilotltd.net/downconv.htm

ATMEL

It’s good to know that the well-known microcontroller manufacturer is also going into the HF market for WLAN, Smartcard, Bluetooth and the rest in a big way. Consequently, as well as containing data sheets relating to the IC’s the company manufactures, the homepage also has application notes and some good articles on the principles. Highly recommended: “A Tutorial on WLAN”, which also contains easy-to-understand information on spread spectrum technology.

Address:
http://www.atmel.com/dyn/products/app_notes.asp?family_id=657

CHIPCON

This company is from the far North – it’s head offices are in Oslo. But the product range (RF transceiver IC’s) is really first class. So it also comes as no surprise to find a very wide-ranging collection of application notes and other documentation. You can even take part in a “Wireless Quiz”, and win prizes.

Address:
http://www.chipcon.com/index.cfm?kat_id=3