Black Face D104 help

[WR989_Dan]

having a issue today with my black face d104 has the push to talk and the chicken choker seems i was sounding bad and distorted on radio today changed the head and sounded fine for a few then stopped keying up know it keys up again but losing modualtion i used 5 diffrent heads took the black face head tried that on another stand works fine looked at the amp board could not see anything visibly burnt out any suggestions

 

[WR0220]

Dirty/Pitted PTT switch contacts will cause this problem.

 

[Wire Weasel]

Also the amp board could be starting to go bad

 

[WR0220]

Since you said you eyeballed the circuit board I figured you checked the terminal strip also, but if you haven't a wire still attached but with several broken strands can cause this problem also.

 

[WR989_Dan]

thanks for all the help just needed some contact cleaner on the ptt contacts works fine

 

[Robb]

Someone asked me the same question on the radio today. The fix for these mics are either dirty contacts; or too much travel on the switch itself when activated. Adjusting it for proper travel when keying is pretty important from what I've gathered 75% of the time. Cleaning the contacts with a clean match book cover or a piece clean paper and some pressure gets it done. Doesn't hurt to add a little contact cleaner to the contacts before running the card/paper through.

In a worst case scenario, I would use a piece of folded-over 400 or 600 grit wet-or-dry sand paper, with only a few swipes through with some pressure. The LAST thing you want to do, is overdo it. A little goes a long way.