| Author |
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Boxcar
| | Posted on Sunday, June 01, 2003 - 10:09 pm: | 
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Got a quick question here. I had a buddy throw a road runner roger beep into a washington of mine and it sounded like total crapola. It would change pitch with the mic gain. 1/4 way up it would distort and about 1/2 way up it would get a little better but still sound terrible. It even had the roger beep coming through the speaker and there is no talkback hooked up to this radio. I wondered if the board was bad so I took it out and threw in another one and it still did the same thing. Is there a way to eliminate this distorted roger beep with the mic gain affecting it? I see the resistors that they send with the board so I was curious if that had to be soldered in line with something or not. I have a cobra 29 that has a roger beep board in it and it does fine. No bleeding through the speakers like my washington. Anyways, any help would be appreciated. Oh, I do run all astatic D104's to my washington. Not sure if that could be it or not since they're amplified mic's.
Thanks guys!!
BoXCaR
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2600
| | Posted on Monday, June 02, 2003 - 1:09 am: |
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Hi Boxcar,
When you unkey a D-104, the white wire (audio) is shorted to ground inside the mike. This short is removed by the switch when you key it (of course). Now the beep's audio output is feeding back through the mike gain control into the white wire to ground inside the mike when you unkey.
One solution is to connect the audio wire from the beep, usually blue, to the mike amp a little downstream from the mike gain control. The beep's volume will no longer be affected by the mike gain setting. Adding a resistor in line with the blue wire will reduce the beep volume if necessary.
The easiest spot to attach the blue wire is the circuit board foil of the center lead of transistor TR32. It's located at the front-right corner of the main circuit board.
73 |
Boxcar
| | Posted on Monday, June 02, 2003 - 4:04 pm: |
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Hey 2600, we'll try the resistor in line and see if that helps and if not, I'll do the audio resistor and go from there. I actually wondered if that TR32 would work or not but I appreciate the help!! |
Boxcar
| | Posted on Tuesday, June 03, 2003 - 4:07 pm: |
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Tried throwing a resistor in line and no luck. Only feeds back through the speaker and sound bad when there's a power mic hooked up because as soon as I unplug the mic and turn the toggle switch on and off for the roger beep, I can hear the beep very faint but it sounds fine then I throw the mic on and all heck breaks loose through the speaker. Tried a stock mic and that worked fine so might just stick to a stock mic for not until something else comes up. |
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