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How to monitor / hear your transmisson?

RF demodulators give you the raw signal like a stereo without a graphic equaliser,

The advert claims
" It is more accurate than most talk-back systems because it samples the AM audio after it has passed through the AM circuitry of your CB radio"

which is also the reason a second radio for listening is the more accurate option,
demodulator audio is not how it sounds when listened to over the air on a radio with its agc + RF & audio filtering,

it may not be the same radio the other guy is listening on but it will be closer to how you sound on air than the RF demodulator..
 
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RF demodulators give you the raw signal like a stereo without a graphic equaliser,........

" It is more accurate than most talk-back systems because it samples the AM audio after it has passed through the AM circuitry of your CB radio"

demodulator audio is not how it sounds when listened to over the air on a radio with its agc + RF & audio filtering,


This is exactly the reason why we monitored our TX audio at our AM broadcast site with RF demods which sampled the RF from a toroid slipped over the transmission line in the TX house. We wanted to hear EXACTLY how the audio sounded to be sure of it's quality. We can't help how good or poor quality of a radio our listeners had to listen too it. In the studios we had top end consumer/pro model receivers with no EQ etc.
 
You must use the "Sealed" type of headphones, meaning the ear cups totally surround and isolate the ear sealing out any chance of the sound from the headphone transducer from escaping. This does not include open cell foam or the like. Otherwise, as stated previously, feedback will result. If you want to monitor your HiFi station you will need good $$ quality headphones of the sealed type like these:

Pro4aa__1.jpg


https://www.koss.com/headphones/over-ear-headphones/pro4aa

Then plug those into a newer Radio Shack or Cobra hand held (HT) 40 channel AM CB with a simple rubber ducky antenna on top. Want to hear how you sound by another radio? Listen with a radio. This works very well for AM CB monitoring ;)

I have read that you can send in your tired old '70s Pro 4AA headphones to KOSS and they'll repair them or replace them under warranty. Problem is, I can't go a couple of weeks without them :)
 
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I got into the habit of wearing the headphones DJ.style from days gone by... One ear covered with the other side of the headphone off to the side. That way you can hear your regular receiver too, duh :LOL:

Since most transceivers are mono, only one side gets energized anyway unless you use an mono to "stereo" adapter.
 
10-20 wraps of wire around your coax, germanium diode and some headphones is all you need.

It would take high impedance headphones like the old crystal type to get much volume and even then it would be hard to hear yourself over yourself. :confused: the frequency response of those old crystal headphones wasn't the best either.
 
It would take high impedance headphones like the old crystal type to get much volume and even then it would be hard to hear yourself over yourself. :confused: the frequency response of those old crystal headphones wasn't the best either.
Regular headphones seem to work well. Only issue i have had was when using a .010-.001 capacitor to roll off the high frequencies. Every time I add a cap the impedance miss match was horrid. Using the diode only the quality was decent!
 
Regular headphones seem to work well. Only issue i have had was when using a .010-.001 capacitor to roll off the high frequencies. Every time I add a cap the impedance miss match was horrid. Using the diode only the quality was decent!

I am rather surprised to hear that actually. While doing some work on my AM broadcast arrays we would often wear a pair of 2000 ohm crystal headphones which had a 1/4 inch plug and clip lead test ends on them. We would simply connect a diode across the leads and listen while out around the tower. The volume was decent without any external noise and this was with a kilowatt radiating only a couple feet away. If you were to use it to monitor yourself the volume would not be sufficient to hear yourself in the headphones over what you hear naturally......not enough to be able to use it as a qualitative measurement anyway. For our use it let us know if we bumped off the air at least.
 
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