The seller I got the fakes from offered a refund straight away when I sent them the picture above.
Anyway, I finally have this radio working again at full power now on FM and AM, but SSB is very low despite maxing out the modulation and injecting a 2.4khz tone at 10mW during alignment.
Think next step is the Audio IC chip TA7205P?
ptbm121d4x Low Power
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Re: ptbm121d4x Low Power
You’ve done the alc mod?
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Re: ptbm121d4x Low Power
Thanks for that.
I have just done the R150 and R28 cap mod, it has squeezed out 1 extra watt on SSB, I am told my audio is better on FM too.
Still very low though on ssb, 4 watts max on ssb with test signal injection but getting max power on FM, even had to back off the alc a bit as it was pushing 16W.
Seems I still have an issue with ssb modulation.....
I have just done the R150 and R28 cap mod, it has squeezed out 1 extra watt on SSB, I am told my audio is better on FM too.
Still very low though on ssb, 4 watts max on ssb with test signal injection but getting max power on FM, even had to back off the alc a bit as it was pushing 16W.
Seems I still have an issue with ssb modulation.....
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- Super Member
- Posts: 125
- Joined: 19 Aug 2016, 21:34
- Location: York
Re: ptbm121d4x Low Power
OK, I have changed the audio chip, SSB is max power now.
Not happy that FM is pushing 15W, so modified the mode switch wiring so FM is limited the same way as AM (see other post).
Noticed some other suggested modifications to try, will do them, then go full through full alignment again, think I am getting there now.
Regards
Bozzy
Not happy that FM is pushing 15W, so modified the mode switch wiring so FM is limited the same way as AM (see other post).
Noticed some other suggested modifications to try, will do them, then go full through full alignment again, think I am getting there now.
Regards
Bozzy