Author Topic: A question about CB Radio  (Read 357 times)

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Offline McBryce

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A question about CB Radio
« on: March 21, 2017, 06:38:36 AM »
Hi radio people,
        back in my very early days I was a CB enthusiast, however I haven't been on the air since the late 80's. Just recently, while visiting my parents I unearthed two of my radios from back then. One is a typical 40 channel car/truck device (Realistic TRC-427), the other is a 40 channel handheld device (GE 3-5979A). Both seem to still work fine. Does anyone anywhere in the world still use CB? Are they of any use to anyone? Are there any hard to find / rare parts inside that people may be craving after to fix some other radios? If not I will scrap them for parts, although there's not much inside that I would use today. But I thought I should ask first before I get the screwdriver to them.

McBryce.
 

Online Richard Crowley

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Re: A question about CB Radio
« Reply #1 on: March 21, 2017, 07:03:05 AM »
It would seem like the most definitive for you in your location would be to simply throw an antenna up and listen for a few weeks to see if there is any traffic in your neighborhood.

Like you, I haven't used it in maybe 40 years, but my understanding is that while it has lost most of its popularity, at least here in the US (and Canadia?) it is still popular with long-haul (inter-city) truckers.  In particular, channel 19 is traditional for communicating road conditions (and location of law enforcement officers).  Dunno whether that practice/tradition ever made it over to the Continent?  I would at least listen to channel 19 for a few weeks before dissecting the gadgets.

Of course, these days, a $20 SDR dongle in an old retired PC could scan the entire band and show you visually what is happening in 11M or any other band for that matter.
 

Offline McBryce

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Re: A question about CB Radio
« Reply #2 on: March 21, 2017, 07:16:16 AM »
Yes, truckers did use CB over here too, but I think it died out here earlier than in the states. I left the handheld CB on channel 19 for the whole of Saturday without hearing a single transmission. Unfortunately I don't really have any way of listening with the vehicle device (which would probably have a much bigger range) without laying cable and putting up an antenna. I suppose I could throw together a simple dipole antenna in the garden if I can find the bits to make one.
I suspected that these are beyond their sell-by date, but I don't like scrapping things for parts when they still function fully.

McBryce.
 

Offline vk3yedotcom

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Re: A question about CB Radio
« Reply #3 on: March 21, 2017, 07:22:09 AM »
Agree it would be worth having it set up for at least several weeks before deciding what to do with it.  A ground plane antenna is simple to make and could be temporarily rigged up.

Around summer you can often get sporadic e propagation and be talking to people 1000 - 2000 km away on the CB.  This is probably easier than it was with less crowding.

Another thing you could do if you're into radio experiments is to use the CB as a tunable IF (especially if the CB does AM/SSB).   A 7 MHz crystal is good for this, giving both amateur and 41m shortwave broadcast reception.  A suitable converter is very simple (2 transistors) and can be built in a night.  Eg

NEW!  Getting back into Amateur Radio: What's new and what you forgot.  Quick restart guide in a 120 page Kindle ebook.  $US $4.99 or equiv.  Just search 'Getting back into Amateur Radio' on Amazon.
 

Offline McBryce

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Re: A question about CB Radio
« Reply #4 on: March 21, 2017, 07:32:07 AM »
One is FM only, the other AM only. I don't do anything radio related these days, which is why I doubt I will ever have any reason to use them again.

McBryce.

For reference, these are the two devices we're talking about. Not exactly highend devices (not pictures of mine) not even back then:

https://i.ytimg.com/vi/bQnrzCQcX0s/maxresdefault.jpg

http://d2ydh70d4b5xgv.cloudfront.net/images/b/1/ge-40-channel-cb-citizen-band-transceiver-handheld-radio-walkie-3-5979a-c9f66f242f3ede783e3558d9ad3d778f.jpg

« Last Edit: March 21, 2017, 07:40:35 AM by McBryce »
 

Online voltsandjolts

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Re: A question about CB Radio
« Reply #5 on: March 21, 2017, 08:50:08 AM »
I recommend a trip down memory lane, just key the mic and shout random CB slang at anyone whos listening!
https://en.wikipedia.org/wiki/List_of_CB_slang

Kojak With a Kodak   =   Police Officer running radar    :-DD

Curse you, internet, for destroying CB!
 

Offline McBryce

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Re: A question about CB Radio
« Reply #6 on: March 21, 2017, 09:12:29 AM »
I was tempted to call QSK :) But I resisted.

McBryce.
 

Online G0HZU

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Re: A question about CB Radio
« Reply #7 on: March 21, 2017, 10:37:14 AM »
Here in the UK there appears to be a healthy market for used CBs amongst collectors. On ebay they fetch quite high prices and I guess a lot depends on the model and condition and exclusivity.

I spent a lot of time on CB when I was a student many years ago and I still have quite a few old CBs here. Most of mine are the old export type and I have several of the classics still boxed and original. eg I have several mk1 and several mk2 Cobra 148GTL-DX radios that are original and boxed. I suspect that these CBs are worth quite a bit of money today.
Your best bet might be to put them on ebay and see what happens?
 

Offline CatalinaWOW

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Re: A question about CB Radio
« Reply #8 on: March 21, 2017, 01:09:54 PM »
CB radios are still sold in virtually every truck stop I've been in, so they are are obviously still in use here in the US.  You don't see the antennas on the trucks as ubiquitously as they used to be, but if you look there are quite a few of them around. 

Ebay is the easiest way to drag a little value out of these.  Just don't expect much.  If you look on Ebay you see new modern gear selling for $40 or so.  But there is old junk also selling for $10 or more. 
 

Offline McBryce

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Re: A question about CB Radio
« Reply #9 on: March 21, 2017, 07:26:44 PM »
There's probably more than $10 worth or parts in them that I can use. Just the channel select switch alone could be useful and probably cost me more if I were to buy one.

McBryce.
 

Offline CJay

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Re: A question about CB Radio
« Reply #10 on: March 21, 2017, 11:19:18 PM »
There's probably more than $10 worth or parts in them that I can use. Just the channel select switch alone could be useful and probably cost me more if I were to buy one.

McBryce.

They're both AM and on FCC frequencies only unless they've been modified to suit the local market.

The channel switch will be an odd thing, the switch will output a series of N-Codes, quite what they'll be depends on the PLL inside the radio, some of them are straight binary but it may count up or down and will definitely have some odd gaps and swaps (for instance channel 3 and 4 are separated by 20KHz on the FCC bands so the N-Code will skip and again there's weirdness happens around channel 22-25 which means the codes reverse), some are BCD and will suffer the same skips and jumps as the binary ones, some will use the same codes as the 7 segment displays (ROM locked PLLs), others will use something different again (another ROM locked variant).

Not particularly easy to repurpose.

'old junk' if it's in good condition can fetch surprising amounts on eBay if it's in good condition, especially if it can be sold as tested.

Personally, they owe you nothing, scrap them for parts if you can't be bothered with testing and selling, if nothing else they'll be fun to take apart and work out the details of but I'm not sure what bits you'll harvest and find useful if you're not going to build more radio stuff.
 

Offline McBryce

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Re: A question about CB Radio
« Reply #11 on: March 21, 2017, 11:48:09 PM »
You're right. I was pretty sure that the Realistic TRC-427 was FM, because I definitely owned an FM Transciever back then, but I've checked an it's definitely AM too. Then I suspect my old "Cobra" was the FM unit, but I couldn't find it during the visit. I possibly sold it a long time ago and forgot.

I hadn't checked the details of the rotary switches, but if they are as you say, then they're not much use. As for condition of the units: The GE Handheld looks like it has just been taken new out of the box, the front of the Realistic is in very good condition, but the painted body looks a bit battered. Either way, looks like they are both heading towards my "For spares" box.

McBryce.
 

Offline Hawke

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Re: A question about CB Radio
« Reply #12 on: Today at 08:42:26 PM »
Gday It's not that the concept died out but rather they migrated to UHF to get away from the noise on 27meg and to take advantage of repeaters in rural areas. The CB bands are quiet but most trucks here and in Canada still have a 27 meg rigs lying dormant somewhere in the cab. Also prior to trunking it was easy to add police receive as most of the radios from the late 80s onward had micro controllers with channels stored in an EPROMs so adding extras was relatively simple compared to manipulating a PLL with wiring, switches etc. Here in Australia the UHF CB band was expanded from 40 to 80 channels a while back but calling it an expansion is stretching it a little bit. They went from 25kc steps in channel separation down to 12.5kc so again it was a bit of simple reprogramming without the need for front end tuning. I still have a lot of good CBs that I couldn't part with like The President Adams or another rig from Asia that had FM instead of AM and the one that got me started into radio and electronics the Roberts RCB 55. You might find a collector for the TRC with Tandy no longer being around and it's vintage now so you never know. Cheers
 


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