"Don Pearce" wrote in message
...
On Wed, 30 Aug 2006 11:30:34 +0100, "Keith G"
wrote:


Forget all the theories Don, it was a short either in the cart or the
wiring. No amount of 'waveform analysis' was going to beat a bit of
tapping
about with a fingertip here....


Whatever it was , it wasn't a short in anything - totally wrong set of
symptoms.



I disagree, the hum started when there was lateral force on the stylus -
suggesting an internal problem stemming from cantilever movement. If not a
'dead short' then summat near enough to induce hum.

Anyway, whatever - *my* suggestion to replace (or refit) the cart appears to
have been the fix he needed....