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Ian B · 8th Apr 2009, 5:42 pm

My KB OB10 Minuet (Trader sheet 1345) sounds good for the first 15 minutes or so after switching on and then becomes distorted. R3 gets too hot to touch, but the voltages on the pins of V1 (6BE6) & V2 (6AT6) don't seem to alter from those specified. I have changed C17 and C20.

Am I barking up the wrong tree in assuming that either V1 or V2 is taking too much screen current and causing the distortion, or does R3 usually run hot? In which case I should be looking elsewhere.....

I don't have any spare valves for this set, so substitution is not an option at this stage.

Thanks in anticipation

Ian Blackbourn

8th Apr 2009, 5:42 pm	#1
Ian B Hexode Join Date: May 2006 Location: Arlesey, Bedfordshire, UK. Posts: 401	KB Minuet distortion My KB OB10 Minuet (Trader sheet 1345) sounds good for the first 15 minutes or so after switching on and then becomes distorted. R3 gets too hot to touch, but the voltages on the pins of V1 (6BE6) & V2 (6AT6) don't seem to alter from those specified. I have changed C17 and C20. Am I barking up the wrong tree in assuming that either V1 or V2 is taking too much screen current and causing the distortion, or does R3 usually run hot? In which case I should be looking elsewhere..... I don't have any spare valves for this set, so substitution is not an option at this stage. Thanks in anticipation Ian Blackbourn