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FREEBANDING & SSB  The popular & classically styled Ranger Superstar SS-158EDX multi-mode transceiver click for larger image  Freebanding is an activity for those CB enthusiasts looking for some extra fun and greater challenges. Non-standard "multi-mode" radios are used for this part of the hobby which can transmit using FM, AM, USB & LSB modes. Such radios are marketed by their manufacturers as '10 Meter Amateur Radio Transceivers', but the main market isn't really licensed amateur radio operators looking for a radio to use on the 10 Meter band, these radios are essentially souped up CB's! Such a multi-mode rigs make great CB's and can be modified, or sold pre-modified as 'export' or 'wide-banded' models so that they work on the 11 meter band that CB uses and as such make excellent and fun wide band CB rigs. Freebanding involves using channels (frequencies) that fall outside the usual CB channels. The majority of these modified 10 meter rigs use "channelised" frequency selection, having 6 or more bands of 40 channels. A "clarifier" control is fitted to allow for the necessary fine tuning of SSB signals. Since the additional channels will be unfamiliar to the CB user more accustomed to standard 80 channel rigs, the use of a frequency chart showing which band and channel combination relate to which frequency To use the chart below it is first necessary to determine which bank / band represents the "Mid Band" "Mid Block" (which is the CEPT / EU band in Europe and the standard CB band in the USA) and then, working either side of the mid-band, it will be possible to see which channel and frequency applies to any given setting. You can see a chart of the frequencies and channels can be seen on this page: Freebanding Frequency Chart Other Frequency Charts Other charts showing the bands and frequencies used for each channel on a particular band can be downloaded from these sites: Tango Mike here: http://www.tangomike.net Transmission1 here: http://www.transmission1.co.uk/downloads/fcc_freq_chart.pdf Open Channel here: http://www.geocities.com/mag2781/5Lowto4hi.doc Country Codes / Divisions For international DXing each country of the world is given a number called a 'division'. For example England is division 26, and Scotland is 108. Contry Codes used for freebanding are called "Divisions" and charts showing these prefixes can be found here:- http://www.freebanding.co.uk/country_divisions.htm Call Signs All Freebanders should have their own individual call-sign. A call-sign can be issued by one of the Freebanding groups such as Tango Mike or Foxtrot Bravo. The call sign comprises the divisional code, e.g. 26, followed by the initials of the group, e.g. FB, followed by the user's unique number, e.g. 999. This would be 26FB999. The CQ call is made by announcing the call-sign as (for example) Two Six Foxtrot Bravo Nine Nine Nine Transmission Modes The mode of transmission favoured for Freebanding is Single Side Band (SSB). The SSB mode can either make use of the Upper Side Band (USB) part of the radio wave, or the Lower Side Band (LSB) part. "Freebanders" generally use Upper Side Band for this use, along with much higher transmitter powers than are legal. Because the SSB mode of transmission is so much more effective and efficient than the usual FM or AM modes, much greater distances can be covered - helped along by the higher transmitter powers that are sometimes used! See our links to Freebanding websites here. However SSB can be a source of extremely troublesome interference to nearby users of televisions, radios and other audio equipment such as hi-hi-fi's and computer speakers etc. Great care should be taken with the radio and antenna installation to prevent any interference occurring. More about Single Side Band and how it works here > Here is the classic Superstar 3900 - the perfect rig to enter the world of Freebanding:   Superstar 3900 Multi-mode Radio - click for larger image Based on the classic Cobra 148 GTL DX CB rig Freeband Frequency Chart What Radio?
What radio should I buy is a question that I am often asked. My reply is usually this: The general recommendation would be a Superstar 3900 (SS-3900) it has 10 watts AM and FM and 20 watts PEP when using SSB. SSB is what is used for freebanding work. The SS-3900 is essentially a clone of the famous and world renowned Cobra 148 GTL DX. It can be connected to a Zetagi B-300 linear amplifier to produce over 100 watts on SSB which should be MORE than enough!! Additionally a 6 digit frequency counter can be added so that you know what frequency you're on. It's not really necessary when working with channelised CB radios, but it can be very handy. There are other choices, and the one that immediately springs to mind is the Galaxy DX-95 T2. This is an all in one 100 watt SSB package with frequency read out. Obviously it's expensive, but when you see that it has the 100 w p.a. and frequency counter built in it's not too bad really. I am told that it performs well and is also well made. Just add a 5/8th wave Silver Rod type antenna as high as possible, some really good low loss coax such as RG 213, a decent power supply and an SWR meter and you're away. HOWEVER I would add that I got bitten by the CB bug which is great for casual chat, then got interested in Freebanding as a 'serious' radio interest, but got a little frustrated with the limitations that these 'freeband' (multi-mode) radios offer. Not that there's anything particularly wrong with the radios themselves or the general idea, it's just that when one gets on the air and realises that there is actually so much more out there on the bands you'll probably soon (very soon) what to do a lot more. It didn't take me many months to realise that such radios were a severe handicap! SO I quickly got a proper amateur radio licence which opened up almost limitless and exciting opportunities on a vast array of other frequencies and bands. Not just a small handful of channels on 27MHz - but everything from 1700kHz to 430 MHz and even beyond. The entry level licence here in the UK allows 10 watts - it might not seem very much but you can get around the world with 10 watts. 10 watts is more than enough for chatting locally on 2m and 70cms and MUCH further afield with a nice Yagi antenna!. For not much more that the Galaxy CB you can have a real radio with modern circuit design. The Yaesu FT-857D is a classic little rig. 100 watts on HF from 1.7 MHz to 28 Mhz; 50 watts on 144 - 146 MHz and 20 watts on 430 to 440 MHz and all the modes you'll need and it has built in digital signal processing and loads of other exciting - modern - things. It really is great fun putting together a good radio station, but please do think about what I have said, because you don't want to go rushing into spending what are quite large sums of money then realizing just a few short months down the line that you find that you need something better and more flexible and that you could have bought right now for not very much more than an old style CB rig. See my AMATEUR RADIO PAGES Take your time to decide what route you want to go and what radio you will buy. Whatever you do, HAVE FUN and GOOD LUCK! Always buy from a good radio dealer - I list many of them in my amateur radio and CB radio links pages. 73 Mike . |
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Mike Smith - www.MDS975.co.uk © 2003 - 2009