new to the forum

[drradio]

hello my name is frank,
im new to the forum and i have technical question.i am not a ham yet but have a kenwood reciever that i listen to on 3880 and 3885 khz.i love the audio quality of the transmitters that broadcast there.i am currently a cb radio operator that loves to restore old tube type cb,s like tram and browning golden eagles,my question is could these transmitters be modified to have that same broadcast quality audio.so far in a tram titan II i have changed the interstage coupling caps to .01 mfd. and that seems to allow some of the low end but sacrificed the highs.i am going to use a studio microphone called an octiva i believe thats the name but am not sure and a berhinger mixer.any advice would be greatly appreciated.

thanks frank

[w3jn]

No reason why not.  I don't think too many have examined the possibility so you're sailing in uncharted waters.  Could be fun, though.  The weak point might be the modulation transformer... but take a look at the typical mods done for Rangers, Vikings, etc., and apply the lessons learned from those rigs to yours.  There shouyldn't be too many differences other than much lower level audio in the CB rigs.

[WA1LGQ]

Hi Frank. Good luck with your CB audio improvements. Most of the signals that I hear on CB in this area (Hartford, CT) have unbelievably bad sounding audio. It seems like the idea is to make your signal sound so bad that no-one can understand you. That is the goal I guess, especially considering that they speak in an undecipherable language anyway. At least in my area I hear lots of truckers on many channels, and a few with linear madness with buzz-saw audio. And a few Spanish stations. Only one channel off in the distance where I hear anything that approaches normal conversations. The point is, maybe you should get together with a group, or maybe you already have a group that wants to do some audio experimentation. You will probably have to all use old tube rigs, or be into modifying the receivers of the more common solid state radios out there. Be aware that you will sound like crap on the usual narrow/restricted receivers in most solid state rigs. BUT it could sound very nice on modified tube rigs indeed. This is what I learned many years ago when we had a group that was doing audio mods to CB radios. You may want to have a graphic EQ in your system to tailor the response for different situations. But thats only one thing on your list.
        Have fun! You will have a lot of experimentation to do and a lot of learning. Larry

[AB1GX]

Frank,

You may want to get a ham licence and restore boat anchors.  They have much more 'glow' than CB rigs.  And they are a bunch more interesting and historic!

There's no need for morse code for any license and the questions for all the tests are published.

I, among many to do so,  went from zippo to an extra class license in an hour and a half by taking three fairly easy tests.

Tom

[wa2dtw]

While it is certainly legal to modify CB rigs for use by a licensed ham on the amateur bands, I'm not sure that it is legal if they are still to be used on 11 meters.

73
Steve WA2DTW

[W1GFH]

I suppose you could modulate the CB rigs externally with a small hi-fi amplifier and small xfrmr like the Hammond 125 http://www.hammondmfg.com/125.htm; they are typically running a final tube like a 6AU6, so you will not need heavy iron. But LGQ is correct, since most CB rig recvrs have a fixed (narrow) selectivity, your efforts will be mostly wasted. You will sound muddy and tubby to people not listening on a SW recvr.

[flintstone mop]

Frank
I'll have to echo the others here. The modified audio will shine better on the Ham bands rather than CB radio. I do not think that CB ops are sitting in their shacks or vehicles with high quality receivers to notice anything you might do to your CB rig.
In fact if it is quality, undistorted audio, they might think something is wrong with your setup. The sound of the echo/reverb and the overmodulated spurious transmitters seems to be all that I hear on the CB channels.
Join us, and the efforts of nice AM audio will be appreciated.
Fred

[flintstone mop]

Hello to Steve
I don't think it's leg al to convert a CB rig to the Ham service. It's an FCC "type acceptance" thing. And the same is true to use a Ham transceiver on the CB band. The Ham rig may be a better unit technically but it's that "Type Acceptance" thing again. Maybe Phil K2PG can clarify this piece of info.
Fred

[Steve - WB3HUZ]

Type acceptance only applies to commercial manufacturers. Amateur ops can convert any piece of radio gear to ham use, as long as it meets spectral purity specs.

Hello to Steve
I don't think it's leg al to convert a CB rig to the Ham service. It's an FCC "type acceptance" thing. And the same is true to use a Ham transceiver on the CB band. The Ham rig may be a better unit technically but it's that "Type Acceptance" thing again. Maybe Phil K2PG can clarify this piece of info.
Fred

[Ed-VA3ES]

Modern CB rigs have decent selectivity specs, and will reproduce decent audio decently.  The typical IF b/w is about 6 Kcs.   Doing audio mods may be worth it.   

I run an "10M radio" on CB: a Uniden 2510, with improved audio in the low level mic circuits and always get praises on the audio.  When I run my FT990 on CB, using various mics and EQ's  I again get praises.  So, the bottom line is yes, improve the audio, it'll be worth it.

That said, get your ham ticket, and join us on AM. You'll be much happier, and learn a lot more.

[W2VW]

Hi Frank,

     Mods done on these CB rigs will help you learn stuff. Great idea. Just don't use the radios on 11 anymore and you should be able to keep out of trouble. Too many hams dsocourage experimentation. Some CB rigs aren't bad. Converted CB rigs are great on 10 metres when the sunspot cycle allows low power communication. There was an article in QST somewhere in 1973-4 dealing with converting an old toob CB to 160 metres. Joe K2UX has an old Tram toob rig on 75 metres, it worked quite well last time he used it.
    As HUZ said, the basic rules for audio modification can be applied to your chickenband boxes. Fattening up coupling, decoupling and reducing bypass capacitors can make quite a difference in audio. Using a wide range flat mic will not work well unless you have some way to shape the tone. The best microphone to use without any equalization is a good old D-104. Throw away the 2 transistor UG8 amplifier and replace it with an MPF-102 so the element can look into a nice high impedance. Also find an element that isn't shot. They don't sound alike so try out a bunch and use the best one.
     One way to pick up some audio headroom on a CB rig is to put a large dissipation resistor in series with the final R.F. power amplifier and bypass the resistor with an electrolytic cap to bypass the audio. This will give you less power out with much cleaner audio as the modulator picks up dynamic headroom. It's a good idea to use an oscilloscope envelope pattern to see what is going on. More power can always be had with linear amplification down the line.
    Good luck and happy "hands on" radio. 

[W2VW]

     Oh and, uh, that Tram Titan uses the same mechanical filter as very expensive Collins hammy receivers. You can diode switch various other cheap mechanical filters in there to really have receive fun. The R-390A 8 and 16 kc filters could be made to work. The I.F. cans would have to be stagger tuned to take maximum advantage.
     A neat project would be a new receiver front end for a Browning or Tram receiver. You could build an outboard converter to take the 75 metre ham band up to 27 mhz. A single toob would work. Take voltages from the CB to save work.

[N0WVA]

 Amateur ops can convert any piece of radio gear to ham use, as long as it meets spectral purity specs.

Since we are dealing with what many call the "chicken band", wouldnt that be more applicable to say "spectral poultry"?

[W1GFH]

Several years ago I acquired a Viking Ranger from a CBer who was selling out his stash of gear. Although completely unlicensed, he appeared to be quite familiar with boatanchors, and told me that he and a small group of CB buddies ran NC-300's, Valiants and Rangers on 11 meters, and were quite familiar with the use of ladder line-fed doublets, scopes, mod limiters, various AM Window audio mods, pro audio chains, etc. They seemed to be doing pretty much what legitimate ham AMers do, except they were doing it on 11 meters. However he also bragged that they universally ran this stuff into commercial-grade linear amps in order to achieve 10KW+ levels with which to "dominate" the local CB channels....

[AB1GX]

Yes, in the old days CBers preferred PA tube was the 4CX10,000.  There's nothing like having a 7500V @1.5A power supply on an 18 wheeler!

[KB2WIG]

"Since we are dealing with what many call the "chicken band", wouldnt that be more applicable to say "spectral poultry"? "


I think thats a fowl idea.... ..    klc

[W1RKW]

Frank,
Go to QRZ.com and do the practice ham tests.  Take about 2 weeks to get familiar with all the Q&A's and go for the license.  A piece of cake.  Then get on the air.  You'll have a blast.
Bob

[kf4qkr]

     Hi Frank ,I am going to echo what the other guys are saying here .HF is a lot easier to get on now with the removal of the code requirements.You already know a lot of what you are suposed to know by being a learned CB operator that does modifications and stuf.The problem with staying a CBer forever is you will always be looking your shoulder because that last modification  you made to your radio or that amp your running (if you run one ,most CBers do) is ilegal! The FCC has just recently fined a CB dealer 150 thousand dollars for selling Galaxy, Connex,and some other uncertified equipment.Get your Ham ticket then you can brag about the amp you built or that rig you modifiied without worry.                                                                                                                Dont throw away the old tube type CB stuf yet. They can easily be modified for 10 meters and more.I am using a Johnson Messenger mod transformer in my homebrew plate modulated transmitter that drives my homebrew amp setup to 375 watts of carrier.Theres more than one way to skin a cat .      Good luck Frank!

[W1GFH]

From what I've seen, the CB culture is so paranoid and anti-authoritarian that the idea of voluntarily supplying their name and address to the FCC (for purposes of licensing) is viewed as a unpalatable breach of personal rights. Other than this, all possible hurdles to the ham license have been removed. We have no more code test, an easily memorize-able written test, appliance-op-friendly gear, and CB-like on air behavior. The final objection of die-hard CBers is part of an old superstition: they just don't want the FCC to have their personal info. And BTW, I'm not saying that this is the case with Drradio/Frank (Frank? Where'd ya go?).

[drradio]

sorry gentlemen i have been very busy,
i was a ham for 10 years and ended up procrastinating and let my licence lapse.my call was N8QDV,and i do plan on taking the test and upgrading.i have been repairing cb radios for 25 years and i love both ham and cb.im not your everyday cb,er i love the more technical side of both hobbies and want to learn more.i listen to your stations on 75 meters and love the audio that is being produced out of these old transmitters and was trying to duplicate that out of old cb transmitters (tube type).i have a good friend that made me an offer that he will give me 3 dx 100 transmitters if i make him 1 good one and the other 2 i can have and all 3 work,so i will have some projects on my bench.thank you for all the encouragement and i will be hitting the books so i can retest and and get on HF.i have been looking at the zener diode negative peak limiter and wonderd if that would work on a heising modulated radio like the trams and brownings.so far i have changed the .001 coupling caps and that brought up the low end some and i know there are other limiting factors and power is not what i want its the broadcast quality sound that im looking for. i have an octiva i believe is the name of the studio mic i have an a behringher mixer also some stock D104,s.so thank you again and i will turn it over to you gentlemen.

frank formerly N8QDV

[AB1GX]

Frank,

I'm glad you're interested in quality signals not power.  As you know the Ham bands are limited to only 1500W PEP, which is not the case for CB.

See you at 3885, tom

[N6WDR]

Frank,

Sounds like you have come up through the Cb ranks as I have done.  I just recently have gotten my General licsence and enjoy being on 75 meters with all these great sounding radios.

I still have all my Browning collection and still like to key up on the Chicken band here in San Diego, but my passion now is to work on my Johnson Valiant and all the audio processing associated with it and talking to stations on 75 meters.
I hope you proceed with geting your licsence, you will enjoy it.

As for the Crappy audio on the Chicken Band radio, there is a big movement on the superbowl (channel 6) most of the big operators are switching over to Johnsons, Collins and such type radios and spending big money for processing.  Go figure... they are spending all this money to sound good and they won't even consider getting a licsence, O'well to each his own.

Richard N6WDR