I decided to switch to a new thread from the previous "Proposed Mark lll Layout" thread. There are photos of the amp on it.
About how warm should the PS transformer on a Mark lll using a SS rectifier substitute for a rectifier tube run?
I checked with a temperature probe on a Klein multi-meter. After warming up for an hour and with no input signal, the surface of the PS transformer on the Mark lll reads about 130F. The adjacent KT88s' surface temperature is about 270F. I'm not certain how accurate the probe is.
The bias on each tube is ~.478 and the B+ at the VTA Mark lll driver board is 463V. This is the Version 11 VTA board. The instructions suggest 400-440V. Is there a resistor I can change to bring this voltage down?
After assembling this amplifier, it's not a standard Mark lll chassis, I added a 40mm fan and peppered the bottom plate with holes. The air is drawn out of the chassis over the SS rectifier is cool.
Is 130F to be expected? The output transformer remains cool, I doubt its temperature rises anymore than 10 degrees, if even that. I think I read somewhere that these amplifiers run quite warm.
I'd appreciate any suggestions or observations. Thank you.
About how warm should the PS transformer on a Mark lll using a SS rectifier substitute for a rectifier tube run?
I checked with a temperature probe on a Klein multi-meter. After warming up for an hour and with no input signal, the surface of the PS transformer on the Mark lll reads about 130F. The adjacent KT88s' surface temperature is about 270F. I'm not certain how accurate the probe is.
The bias on each tube is ~.478 and the B+ at the VTA Mark lll driver board is 463V. This is the Version 11 VTA board. The instructions suggest 400-440V. Is there a resistor I can change to bring this voltage down?
After assembling this amplifier, it's not a standard Mark lll chassis, I added a 40mm fan and peppered the bottom plate with holes. The air is drawn out of the chassis over the SS rectifier is cool.
Is 130F to be expected? The output transformer remains cool, I doubt its temperature rises anymore than 10 degrees, if even that. I think I read somewhere that these amplifiers run quite warm.
I'd appreciate any suggestions or observations. Thank you.
