No Phil, I was thinking more about dried out electrolytics. It is
possible that such a cap has dried and gone leaky that is causing the
mute circuit to stay active.


--
Woody

harrogate3 at ntlworld dot com


"Phil Allison" wrote in message
...
RJH wrote:


Phil is right but I would wait until you have extracted it before
buying a replacement as it could be Ni-Cad or Ni-MH depending on
the
age of the tuner, and they require slightly different charging
regimes. Equally it could be 3V, 3.6V or 4.8V although I would
admit
that the size suggests the latter.


** AFAIK, Quad FM4s only ever used 4.8V NiCd battery packs with four
cells specially made for memory back-up. It was trickle charged at a
few mA whenever the tuner was powered up.

I doubt any re-engineering is needed to employ a four cell NiMH pack
instead.


.... Phil