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WHAT'S GOING ON WHEN IT COMES TO HIFI CB?

That that's not as difficult as difficult as you might think. A 15 to 20k tone will modulate my CB. You can see it on a scope and a 20k tone looks like a carrier 2 channels up.


What mods did you do to the CB and what level is the 20KHz audio as compared to the standard 1KHz reference tone that is generally used?
 
What's this prove ?? It's a home-made broadcast transmitter. We were talking about hi-fi in CB RADIOS. I don't doubt that there are some cb rigs out there that have been modded for wider audio bandwidth, but 15 khz ??? Come on ... give me a break. 15 khz of audio bandwidth is akin to the clowns who say that they can get 100 watts rf out of a stock 29LTD.
Proving that your modded rig is capable of broadcasting a 15KC audio signal is a simple thing. Hook an audio generator to the mic input on the radio, keyup, and sweep the audio input freq from 1khz to 15khz while monitoring the rf output on a 'scope. If audio at 15kc actually modulates the transmitter, I'll be the first in line to shake the guy's hand.

- 399
My 148 has the same sound, but does it really matter to you? Is your point it can't be done or shouldn't?
I'm answering a thread that I have a little insite on. What are you doing?
 
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What mods did you do to the CB and what level is the 20KHz audio as compared to the standard 1KHz reference tone that is generally used?

At that time it was audio gear feeding the AM regulator of a TR296, a cobra 148 clone. Remove C174 and pipe audio into the hole for the positive side of the cap.

Now there is a homebrew version of the motor mouth maul board (a friend built it and gave it to me) feeding the collectors of the driver and final. The board controls the carrier, negative and positive modulation peaks. I don't sound much different than I used to but it's easier to keep things under control.

With the equipment I'm using I can't give you a good answer on the levels. I can say it took more audio to reach 100%. Tones were created with audacity or an app on my android phone. Tones come from the PC or phone, into a behringer mixer, through the audio gear I mentioned earlier and then to the radio. The response certainly isn't flat from 1 to 20k but I don't know the limitations of the audio equipment I use or the radio.
 
At that time it was audio gear feeding the AM regulator of a TR296, a cobra 148 clone. Remove C174 and pipe audio into the hole for the positive side of the cap.

Now there is a homebrew version of the motor mouth maul board (a friend built it and gave it to me) feeding the collectors of the driver and final. The board controls the carrier, negative and positive modulation peaks. I don't sound much different than I used to but it's easier to keep things under control.

With the equipment I'm using I can't give you a good answer on the levels. I can say it took more audio to reach 100%. Tones were created with audacity or an app on my android phone. Tones come from the PC or phone, into a behringer mixer, through the audio gear I mentioned earlier and then to the radio. The response certainly isn't flat from 1 to 20k but I don't know the limitations of the audio equipment I use or the radio.


OK I was curious as to where the audio was inserted into the radio. Bypassing the regular audio amp circuits would certainly be the way to go in order to widen the freq. response. I was also curious as to the flatness of the freq. response because some folks simply say it will make power at whatever mod frequency without saying how flat it is. Some choose the 3 dB points, based on that being half power I guess. In broadcasting we use the -1dB point to determine freq. response.
 
Maybe those gates show some wide audio but I've heard a lot nicer sounding stations on the air than any of those. Maybe it's just the video recording not doing them justice. Some people are just born with a golden voice - no hifi required :)

 
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Maybe those gates show some wide audio but I've heard a lot nicer sounding stations on the air than any of those. Maybe it's just the video recording not doing them justice. Some people are just born with a golden voice - no hifi required :)


You can't improve on that.
 
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well this thread certainly turned a corner didn't it!

Stellasarat asked what was going on with the stations that used Hi Fi audio on the CB band, and the following posts were right in line with answering and discussing his chosen subject.

THEN!
someone decided to post their opinions as if they were facts. They decided that they were the judge, jury, and executioner of all things radio, and was sure to let everyone know why they should not be experimenting with the things they are experimenting with, lest they incur the bad favor of the one person whose opinion matters with regards to the radio hobby.

Can anyone guess who this was?
Is it the person who consistently shows disdain and condescension for the CB hobby and the people in it?
yep.

does this same person seem to always interject their opinions into discussions as if they were the only opinions that mattered?
yep.

does this same person who seems to hate the tenets of CB radio always seem to hang out in the CB radio section of this forum?
yep.

Does this person have any idea what a pompous windbag they sound like?
do they realize how quickly most of us would back out of a QSO with them because of what an ass they came across as?
Does this person see that they are not wanted or needed AT ALL in this section of the forum?

nope.
LC
Sounds to me like you don't believe in free speech unless it only agrees with yourself. This is an open forum for all members.

There are moderators to determine if someone goes too far. It is not up to you to determine who belongs and who doesn't.

It also appears you have some kind of complex.

If you have a problem with somebody posts or their views, then ignore them and move on.
 
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Sounds to me like you don't believe in free speech unless it only agrees with yourself. This is an open forum for all members.

There are moderators to determine if someone goes too far. It is not up to you to determine who belongs and who doesn't.

It also appears you have some kind of complex.

If you have a problem with somebody posts or their views, then ignore them and move on.

why on earth would you assume i was referring to you?
LC
 

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