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It’s perfectly legal to listen on the aircraft channel. An air band scanner starts at around £100. Look on Amazon. You need a license to transmit but you’ve got to be in an aircraft or in ATC to do th

GUILTY AS CHARGED! I was on from 81 through to 88, and i was one of the TURKEYS that iron cross and friends tried to get. but i was young and stupid then. now i'm just old and dumb! i was always mobil

Right to get this thread back going again.. there is another recording of old 'boxer' on http://ukcb.tripod.com there was two more of tony rifleman, but recorded quality was low, so being re-done. i

  • 2 months later...

hi again..

on the Jesan, i could find a use for it, but then again it'll probably just sit in the big box of unused stuff :)

best bet is to eBay it, you could see £20 or so for it..

on the recordings mick, i have a few with what i think is gasman on a new Boxer tape (not on-line yet)

but i do have three of the Alpha organisation listen on http://livecbradio.co.uk under 'watergates' there's the Alpha's on there..

on the new load i have it's mostly Boxer, Kath, Betty happiness, smokey, 10-1 tom and a few others..

when i get more time i'll transfer the lot to MP3 and get them on the site for streaming..

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  • 9 months later...

As of 27th June Am and SSB on the Mid band will be legal..
will anyone actually be bothered ???

this means the old AM channels will be legal (if you use a legal radio)

but no one will check, hey you don't even need a licence to use CB

http://stakeholders.ofcom.org.uk/binaries/consultations/citizens-band-radio/statement/statement.pdf

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Now that was fun trying to get the SWR down before the output transistors blew up, well that's what they told us would happen if you had a high SWR. I can't remember anyone's output trannies blowing coz of high SWR, surly they'd have a protection circuit built into them to shut them down if they got to hot? Mine fed into a horizontal dipole in the loft, I pressed the low power button (down to 0.4 watts) when the telly was on to avoid interfering with it..

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I bought two whip antennas, one stainless steal, one fibreglass.

Recently bought a centre for them to make them into a dipole.

Got a Harrier CBX and York 863, just a matter of some coax, and motivation.

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Steve, CB's don't have protection circuits in the output, would make them more expensive.

Both my ham HF and VHF/UHF radios have that protection, but it is not 100% protection, keying the mike up with no antenna is asking to smoke the output transistors!! Most modern ham rigs have expensive mosfets as the final amplifer in them nowadays, they hate high standing waves.

I think all the solid state militray radios you worked with would have protection on the output.

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This is a long shot and I hope it's ok to post.

I'm looking for someone that used to attend a CB club back in the 80's more specifically around late 85 early 86 possibly in the meadows, Carlton/sneinton areas (they are the only areas I no my mum has lived). The only thing my mum can remember about him is that his name is Alan. He was Possibly in his 20's. I have no idea what he looks like to give you a description. He went out with my mum for a short while her name is Pam and she would have been in her very early 20's. She is very short (4ft 11) and has brown hair.

I no it's not a lot to go on but does anyone know who this Alan might be? I no it's a long shot but with the lack of information I have it's the only shot I have.

Thanks

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John, so it was true that a high SWR'd blow the trannies, I thought it was hype, didn't think they'd be daft enough to not have protection..... The Army rigs we used were all valved, (pre Clansman days) the man packs (A41/42) were 90 volts HT (ouch had a few tingles) & (I think) 3 volts LT & the vehicle fitted ones (C42/45) had a vibrator (no not that sort :) ) power supply for the HT. They were almost indesrtuctible, many a time I thought "hmm this isn't getting through very well!" No wonder there was no aerial connected, & when a proper aerial wasn't to hand a bent welding rod or similar was used, lol..

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Modern solid state radios have "fold back" protection, but it's not instantaneous nor is it cheap, so CB's don't have it.

The power amplifier modules used in modern VHF/UHF/SHF etc radios, have built in fold back protection, so makes it easier for the RF design engineer.

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I've read somewhere about foldback protection, I'll have to read up on it again. The man pack radios had a thing where the TX section valves were run at reduced LT voltage when in standby, to save the battery I pressume, you had to remember to wait 2 seconds after keying before talking to give the heater time to come up. Clansman trannie stuff came in just after I left..

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Foldback protection uses the return standing waves to generate a small current Steve, it's rectified and fed back to the RF output amplifier's bias circuit... Think of a Bird wattmeter and how it reads a standing wave, then that's fed into the bias circuit and reduces, folds back, the power to protect the final amplifier stage.

In my HF radio, a 4:1 SWR will limit the output to around 20 watts, 5:1 almost cuts the RF amplifer to zero output.

Tubes were more tolerant of high SWR's as they had a tunable tank circuit that acting like a modern day antenna tuner. So when you load an old tube transmitter, you are matching the tubes impedance with the antenna, with the tank circuit variable capacitors for maximum output, or grid current, whichever the radio has instrumentation on.

On external tube amps, I tune for max power out, always keeping an eye on not overloaded the grids....Tubes are getting pretty expensive these days!!!

Couldn't recall the name of the unit in Bird meters, just came to me, a directional coupler.

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Just had a browse of some websites on foldback, I understood straight away how the rectified return current altering the bias on the output trannies to reduce output power works, very clever me thinks... Yes I can imagine valves (tubes) being expensive nowadays..

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There are countries making power rf tubes, China and Russia, Chinese tubes are crap, even matched pairs, quad matched, don't last long ...Svetlana Russia's premier tube manufacturer are the best, although they are a lot more expensive than Chinese Taylor tubes.

There is one US manufacturer, but they specialize in the metal ceramic type tubes for high power applications from 1Kw to many hundreds of Kw power tetrodes used in radio stations and TV stations.

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They told us the army still used valves because they were more resistant to the electromagnetic pulse from high altitude nuclear explosions, how they made the Clansman with there trannies resistant I don't know, some kind of back to back diodes with resistors that dissipated the steep rising voltage? They came in after I left so don't know much about them..

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Many years back, when I lived in Sacramento, I was friends with another ham who worked part time for the US air force, he was an electronics expert, he wrote a paper for the air force on RF cable connectors, which is still material taught to military electroncs engineers!!

Problem was, he had to be careful with what information he could relate to any of us, as a lot he knew was highly classified.

We were discussing EMP's and the dangers they represent to solid state components, what they actually do is create high voltage pulses that last for a few milli seconds in certain wavelengths. They destroy the junctions of solid state devices.

He did relate that most military equipment is "hardened" to withstand most EMP's, how??? He wasn't allowed to inform us, classified!

There may be information around now that's declassified, I don't know, never searched for it, but probably the best way to protect electronics is to keep it disconnected from the mains, have no external connectors plugged in and keep the devices in a Faraday cage that is well grounded. Something like the cages used to isolate electronics during testing stages to avoid allowing RF leakage to the outside world.

Problems with EMP's, are there are several wavelengths involved, different types of nuclear devices produce some of the most destructive, then there is our Sun, a solar mass ejection of X5 or more can cause catastrophic damage to power transformers as well as sensitive electronics...How do you provide protection from all sources???

How solar SME's cause damage is by "saturating" the cores, what happens is they just become overloaded, produce a lot of heat and the windings burn out...Imagine that on a world wide scenerio!! It did happen in Quebec a few years ago, wiped out hundreds of power transformers, I think it damaged some in the northeast states of the US at the same time..

Deep subject, EMP's!!

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My eldest son used to enjoy CB radio when he was about 13. He enjoyed guiding truckers to their destination as they came off the M1. Most of all he enjoyed chatting up girls. Until some dirty barsteward started making suggestive comments to them. It put him off after a while.

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So those rigs that were sold in the masses in the 80s (UK FM band, 40 channel) - did they become illegal at some point and are they legal again now?

eng

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  • 7 months later...

currently

40ch FM CB 27/81 radios are legal.

PR27GB 'mid band' CB is legal.

and now AM/SSB on the 'mid band' is legal BUT you are meant to use type approved radios..

but seeing as OfCom (DTI/Buzby) don't care and can't afford to trace people CB ids a free for all, use what you like..

most CBers run 100w now days on illegal radios, and mostly on ch19..

the live stream at http://livecbradio.co.ukis still on 24/7 and now has a ch19 stream so you can listen to the mentally challenged, sexually frustrated and society rejects that are on there..

there's one or two coming back on, but as one comes on and another sells up or passes away..

CB will never be what it was, but with the US on AM still coming in (since 2010) it's well worth buying and digging your old AM/SSB radios out and trying to chat to the yanks..

and lets not forget that 40ch on mid band that died a death after a couple of years, very quiet at night and free of all idiots..

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