martyn668 Posted June 23, 2009 Share Posted June 23, 2009 I have a 40 channel European (French) CB radio, and recently in a group of French vehicles where 5 of them had CB's, two of us could speak and hear each other relatively clearly, and the other three could all communicate clearly amongst themselves, but the two groups could not communicate. We were all on Channel 10, and whilst I could hear indistinct crackling and talking, I couldn't make out what they were syaing, nor they me. It would seem channel 10 had two frequencies that were fairly close but not identical. We didn't try changing channel, but I assume (maybe wrongly) we would have had the same problem on all channels. Is this possible? Do I need to "tune" my CB? Does the other guy I could talk to also need to do the same? NB I had the SWR set up with my English CB fitted, but I have been told it is the vehicle that it SWR'd rather than the CB, so switching the two units (by unplugging the aerial from one and plugging it into the other) should mean that if the SWR is OK for one, it is OK for the other. But that's transmission anyway isn't it, and not necessarily reception. Any ideas? Quote Link to comment Share on other sites More sharing options...
cipx2 Posted June 23, 2009 Share Posted June 23, 2009 Sounds like one group was using FM and the other one AM. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted June 23, 2009 Share Posted June 23, 2009 From memory you have the various combinations of FM/AM, UK/EU, and 40/80 channels. Sometimes they overlap enough to make something out. Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 UK & Euro/CEPT frequencies are different, the UK is chaging to use the Euro/CEPT frequencies in 2010 when the UK only 40 channels/frequencies will be taken out of use. UK & Euro/CEPT frequencies Quote Link to comment Share on other sites More sharing options...
Matt Neale Posted June 23, 2009 Share Posted June 23, 2009 UK & Euro/CEPT frequencies are different, the UK is chaging to use the Euro/CEPT frequencies in 2010 when the UK only 40 channels/frequencies will be taken out of use. Bugger! I didn't know that Ralph. Looks like I'll have to finally retire the Midland 4001 rig that I've had since about 1982!!!! Matt Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 Withdrawal of the 40 UK-only CB channels 1.8 At its peak, there were 300,000 CB licences in the UK. However, use of the CB radio frequencies has declined, and the number of CB licences on issue has fallen to under 24,000. Currently there are 80 CB channels available: 40 UK-only channels and 40 pan-European channels. The present level of CB use, which is steadily declining, does not justify the retention of all 80 channels. RA therefore proposes to close the 40 UK only channels. To prevent this closure causing major inconvenience, we propose to give a minimum seven years’ notice of this closure. This means the closure date will be 30 June 2010. from this document http://www.ofcom.org.uk/static/archive/ra/...ondoc/index.htm Quote Link to comment Share on other sites More sharing options...
martyn668 Posted June 23, 2009 Author Share Posted June 23, 2009 Wasn't clear sorry - my French CB has all the French frequencies, so should have been identical to theirs. My English CB has all the English frequencies. The English one was used to set up the SWR, and although I've only spoken to one other person on a greenlaning trip, it seems to be working fine. Now I unplug the English CB, and plug the French one in, and can only talk to one other French person (on a French CB). From all the other French CB's I get very distorted signals - too much to make out what they're saying - and no amount of playing around with the squelch sorts it out. Nor can they hear me properly. Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 the frequency is different so try re setting the antenna SWR, there's a guide in the tech archive forum index. Quote Link to comment Share on other sites More sharing options...
cipx2 Posted June 23, 2009 Share Posted June 23, 2009 You were clear from 1st post, at least for me. Did you make sure you (all 5 of you) were using the same type of modulation, that is either AM (amplitude modulation) of FM (frequency modulation)? Forget about your English radio, SWRs, antennas etc for the time being. I'll tell you about those later. Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 CB SWR of antenna also make certain the antenna mount has a good ground connection to the vehicle. Quote Link to comment Share on other sites More sharing options...
cipx2 Posted June 23, 2009 Share Posted June 23, 2009 Ralph, the SWR has nothing to do with the fact that he couldn't receive the others. Period. Give Martyn the chance to reply my question, please. Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 would if it's way of frequency. Quote Link to comment Share on other sites More sharing options...
cipx2 Posted June 23, 2009 Share Posted June 23, 2009 It would certainly and definitely not. You can use any wire, no wire, your finger, no finger, antenna cable, no cable at all etc in place of the antenna and if the signal is strong enough, you'll hear it more or less loud but clear. Trust me. Take my word for it Quote Link to comment Share on other sites More sharing options...
western Posted June 23, 2009 Share Posted June 23, 2009 put the info up then, so it can be read & acted on, Quote Link to comment Share on other sites More sharing options...
cipx2 Posted June 23, 2009 Share Posted June 23, 2009 What info? The SWR has a (rather small) influence on the level of the received signal but not on the clarity/intelligibility of the signal. If you want a video demonstration that a transceiver can receive good quality audio without an antenna (without antenna means SWR= infinite) not matter the type of modulation (AM, FM or SSB) then wage me a tenner payable as forum contribution (to be confirmed by forum treasurer) and you're on B) Edit: Correction: No SSB as I have only one SSB capable transceiver Quote Link to comment Share on other sites More sharing options...
disco_al Posted June 24, 2009 Share Posted June 24, 2009 RA therefore proposes to close the 40 UKonly channels. To prevent this closure causing major inconvenience, we propose to give a minimum seven years’ notice of this closure. This means the closure date will be 30 June 2010. How can they "close" a frequency that's set by the unit itself? it's not as if CB's use relay/repeater stations to broadcast, so old uk40 models should still work, and not become obosolete Quote Link to comment Share on other sites More sharing options...
Anderzander Posted June 24, 2009 Share Posted June 24, 2009 I'd imagine they will give the channels to someone / something else - and if they are used by the public on a cb then it will be an offense. It'll be treated like any other illegal use of frequency ranges. Quote Link to comment Share on other sites More sharing options...
sean f Posted June 24, 2009 Share Posted June 24, 2009 How can they "close" a frequency that's set by the unit itself? it's not as if CB's use relay/repeater stations to broadcast, so old uk40 models should still work, and not become obosolete They close them by technically making it illegal to use them. I say technically as AM and SSB sets have always been illegal in the UK (unless you have a HAM radio license, which is a whole different thing). but have been widely used. Also legally you should have a CB license to use a set, so few people have bothered its not enforced. You will be able to carry on using the old frequencies but won't be able to buy new equipment so as old sets die the frequencies will become redundant till every one is using the new ones, hence the long run in period. Quote Link to comment Share on other sites More sharing options...
disco_al Posted June 24, 2009 Share Posted June 24, 2009 Also legally you should have a CB license to use a set, so few people have bothered its not enforced. no longer needed in the UK since early this century IIRC Quote Link to comment Share on other sites More sharing options...
LandyManLuke Posted June 24, 2009 Share Posted June 24, 2009 I agree, the CB license was deregulated, mainly due to the decline in use as already discussed. Quote Link to comment Share on other sites More sharing options...
Anderzander Posted June 24, 2009 Share Posted June 24, 2009 It was abolished 8th of December 2006 - http://www.ofcom.org.uk/radiocomms/ifi/lic...lasses/citizen/ Quote Link to comment Share on other sites More sharing options...
disco_al Posted June 24, 2009 Share Posted June 24, 2009 i'd imagine they will give the channels to someone / something else - and if they are used by the public on a cb then it will be an offense. It'll be treated like any other illegal use of frequency ranges. can't see it being that much of an issue, they never used to police the frequencies that much in the old days of cb - i remember when the shout used to go out and aerials used to disappear overnight "look out - the dti are in town" lol Quote Link to comment Share on other sites More sharing options...
Happyoldgit Posted June 24, 2009 Share Posted June 24, 2009 can't see it being that much of an issue, they never used to police the frequencies that much in the old days of cb - i remember when the shout used to go out and aerials used to disappear overnight "look out - the dti are in town" lol Hmmm - they did back in '78 / 79 around our way as my wallet knew to its cost. Quote Link to comment Share on other sites More sharing options...
disco_al Posted June 24, 2009 Share Posted June 24, 2009 Hmmm - they did back in '78 / 79 around our way as my wallet knew to its cost ahh - back in the AM days moreso i suppose, but in the early 90's when i had my first rigs (i miss my 148 gtl-dx) it wasn't so much of an issue. Quote Link to comment Share on other sites More sharing options...
western Posted June 24, 2009 Share Posted June 24, 2009 What info? The SWR has a (rather small) influence on the level of the received signal but not on the clarity/intelligibility of the signal. If you want a video demonstration that a transceiver can receive good quality audio without an antenna (without antenna means SWR= infinite) not matter the type of modulation (AM, FM or SSB) then wage me a tenner payable as forum contribution (to be confirmed by forum treasurer) and you're on B) Edit: Correction: No SSB as I have only one SSB capable transceiver transmit with no antenna connected & possibly wave good night to the transciever as it is likely to damage it. Quote Link to comment Share on other sites More sharing options...
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