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Hi Guys here s one to get your teeth into. My amp is complete and ready to do initial settings,I have done feedback and bias up to no4 on the manual (400ohms ) i switch amp on do set the voltages (350mv),hum comming from right speaker but no sound from left.All tubes are on and the ones on the working side (el84 )seem hotter. i have set the voltage on the right side r28 andr25 but no reading on my meter from r22 and r19. All tubes are new. Can some body please point me in the right direction thanks

It appear that two tubes are operating, and drawing plate current and that two are not.

A little bit of hum is normal if you do not have the input connectors shorted or loaded to ground.

For the two (left channel) that give no reading, the first step would be to to check the plate voltage on pin 7 of each of those two tubes. If there is no voltage present, then go back to the terminal strip or connection for tha centre tap of the output transformer where it connects to B+. It appears there is a possibility that there is an open or not complete connection.

Also make sure that those two tubes have lit filaments, as cold tubes also do not conduct or draw plate current.

HTH

/ed B