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Old 5th March 2016, 03:04 PM
John Caswell John Caswell is offline
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Join Date: Dec 2005
Location: Wokingham, Berkshire
Posts: 1,668
Default Re: KT88 Intermittent problem

Hi Alasdair,
Intermittent problems can be the very devil to find.
Valve substitution is the starting point. If not successful then--------
I suggest that you start by turning it upside down and setting it in a immovable position, removing the baseplate, connecting it to the power line, speakers, signal etc then powering it up, setting the volume to a sensible level.
Try to get hold of a plastic knitting needle and, with one hand in trouser pocket, try prodding the various joints starting with input sockets - volume control - ECC83 grids pins 2&7, anodes pins 1 &6 plus associated wiring and components on the tagboards, then follow through to the 5687 and finally the KTT88 then report back here.

John
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