Weird readings on 6L6 Express 'Géraldine'

camden_guitarist · Post by **camden_guitarist** » Thu Apr 23, 2009 6:27 pm

Hi there everybody, I tried to make my voltage chart today, and all checked out quite well, though I did have one really weird reading on my filaments voltage, why does it only read 3.2V??? Can anyone tell me what I did wrong, my Express sounds fine and all is working but I'm a bit puzzled.

Any input would be nice.

Cheers,

Paul.

Structo · Post by **Structo** » Thu Apr 23, 2009 6:49 pm

Are you measuring AC voltage across the two wires to the tubes?

If you only measure one and have your black lead clipped to the chassis, you will only get half the voltage reading.

camden_guitarist · Post by **camden_guitarist** » Thu Apr 23, 2009 7:23 pm

Thank you very much, that's it, I was using the prescribed method of hooking the black lead to a good grounding point on the chassis and probe with only one hand.

Thanks again.

Paul.

paulster · Post by **paulster** » Thu Apr 23, 2009 7:37 pm

The centre-tap of the heaters is tied to ground, so the heaters are effectively at +/-3.15Vac when measured referenced against the chassis.

You're all good.

The Amp Garage