>-----Original Message----- >From: [email protected] >[mailto:[email protected]] On Behalf Of tahrens301 >Sent: Tuesday, November 24, 2009 2:43 PM >To: [email protected] >Subject: [Repeater-Builder] Spectra Audio Popping after Capacitor replacement > >Hi Folks, > >I've been working on these Spectras, and so far, >the capacitors have done the trick. > >But on this last radio, the speaker pops whenever >the audio path is open (unsquelched, signal, mode >change, etc). > >Just curious if there's something I've missed. > >Thanks, > >Tim
The popping is due to a DC voltage change at the input to the speaker amp. Leaky caps are the most common cause of this, but if you've changed the caps and not cleaned up the cap residue on the board the crud can be conductive and essentially shunt the new cap with a resistor. So cleaning the board of all leftover residue may help. I've been told the residue contains boric acid, I'm not a chemist, does anybody know what a good neutralizer is for that ? If I knew, I'd use that, then some MEK (which you can find in cans in the paint section at Home Depot). Mike WA6ILQ
