Help Needed...1 Tube won't light up on Atma-Sphere M50

OTL Asylum

OTL, Output Transformerless Amplifier User Group.

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Hi,
I am having some problems with one of my Atma-Sphere M50 amps. I would like to see what other members think of the situation. (perhaps Ralph or Legendre can chime in as well before I send it back to the factory for service) When I fired up my amp this evening to standby mode, I noticed that one of my tubes did not light up. I tried switching out that tube for another one, but that too failed to light up. I did not switch the amp to full power after that. From my understanding, the standby mode supply heater current to the tubes to warm them up before full power up. Before this episode, I had recent problems with this amp with tube plates glowing orange. I tried replacing the glowing tube with a new one but I noticed that another tube in a different socket would start to glow orange a few hours later. During this whole time, the amp held steady bias at the factory recommended 0.55 amps. What do you guys think? Thanks

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Topic - Help Needed...1 Tube won't light up on Atma-Sphere M50 - speedracerucr 21:25:43 07/18/05 (8)

Update - Speedracerucr 21:11:38 07/23/05 (1)

Re: Update - 'tsup 08:59:20 07/25/05 (0)

Re: Help Needed...1 Tube won't light up on Atma-Sphere M50 - speedracerucr 09:11:26 07/19/05 (4)

Re: check your power tubes - Ralph 13:07:40 07/19/05 (3)

Re: check your power tubes - Speedracerucr 18:49:43 07/19/05 (2)

Re: check your power tubes - 'tsup 05:40:42 07/20/05 (1)

correction - Tre' 19:43:30 07/20/05 (0)

Re: Help Needed...1 Tube won't light up on Atma-Sphere M50 - 'tsup 22:47:10 07/18/05 (0)

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