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Speaker feedback

Maurice Bersan
 

I just got home from work, fired up the UBITX V5 and find that my microphone audio is is being fed back through the speaker. Otherwise the radio is working fine. wife tells me we had a small surprise storm during the day and I'm fearing the worst. Is there anything I should check first. I've had a look around inside with a magnifying glass but can't see anything obvious.
Any help would be appreciated.

 

Probably antenna damage in the storm. High SWR may cause this.

Raj

At 08-10-19, you wrote:
I just got home from work, fired up the UBITX V5 and find that my microphone audio is is being fed back through the speaker. Otherwise the radio is working fine. wife tells me we had a small surprise storm during the day and I'm fearing the worst. Is there anything I should check first. I've had a look around inside with a magnifying glass but can't see anything obvious.
Any help would be appreciated.

MVS Sarma
 

Raj, i too suffered this after a mod to work final pa at 19v . I regulated 19 to 12v thst passed thro on off switch. Here i committed a mistake causing a ground loop. At the switch i wired 47uf  using ground return on volume control gnd.

Later realising the blunder i removed it. Now have a 470 uf on  red and black wires of the 3 pin power plug. 
 No audio feed back now.  Hope this might help other
Sarm
  vu3zmv

On Tue, 8 Oct 2019, 1:34 pm Raj vu2zap, <rajendrakumargg@...> wrote:
Probably antenna damage in the storm. High SWR may cause this.

Raj

At 08-10-19, you wrote:
>I just got home from work, fired up the UBITX V5 and find that my microphone audio is is being fed back through the speaker. Otherwise the radio is working fine. wife tells me we had a small surprise storm during the day and I'm fearing the worst. Is there anything I should check first. I've had a look around inside with a magnifying glass but can't see anything obvious.
>Any help would be appreciated.




Maurice Bersan
 

Thanks for the replies so far. I have checked antenna etc using another radio but no faults found. I'm wondering if I have had this issue from the beginning. It only occures when I get up close and personal to the mike or blow into it that I notice any feed back through the speaker. Anyone else noticed this?
Cheers
Maurice

Maurice Bersan
 

Solved! I built the simple s meter circuit from the hamskey site a couple weeks ago and that circuit is the problem, I just hadn't noticed the feed back it produced. Thanks MVS Sharma for the clue as this little circuit also connects to the high side of the volume pot. I removed it and we're back to normal now. Just not compatable with v5 board I guess.
Cheers all 

 

Probably the wire from your add on circuit and the volume control is picking up RF. Try using a shielded wire.

At 10-10-19, you wrote:
Solved! I built the simple s meter circuit from the hamskey site a couple weeks ago and that circuit is the problem, I just hadn't noticed the feed back it produced. Thanks MVS Sharma for the clue as this little circuit also connects to the high side of the volume pot. I removed it and we're back to normal now. Just not compatable with v5 board I guess.
Cheers all