JTM45 Build with various output tubes and GZ34/Solid State Rectifier

[Spencerleehorton]

yep as i thought, had to be connected, now getting 465v on B+ wth diodes, will leave on now and see how hot the mains txf will get.
started at 23C its now gone up to 27C after about 5 minutes.
first 32uf cap connection is at 38C?
could it be a dodgy 32uf cap?

 

[Spencerleehorton]

ive used a bias calculator which was provided in this thread, and it said that for EL34 at 70% it should be 43mA with 403v which is what i was getting.
is the bias calculator wrong?

Im now at 443v B+ so will adjust bias to 39.5mA

BTW. have ordered some KT66.

 

[Spencerleehorton]

its been about 30 minutes now and its only at 31C, warm to the touch but doesnt seem to be going over 40C like before, the bottom end with diodes is much tighter as well.
will keep monitoring.

 

[Spencerleehorton]

45 minute mark and now gone up to 38C and still climbing!! getting pretty warm now!

 

[Spencerleehorton]

ive spoken with Michael at modulus amplification where i got the Mains transformer and Choke from and he has said that 39C is fine and not a problem.

 

[StarTrucker]

are you having any other problems with the amp?

 

[Spencerleehorton]

One of my concerns was it was getting rather hot, my only other concern is the bias, i am using a 68k for the 180k into the diode and a 5.6k then a 27k with a 50k pot, should i be concerned that this is vastly different than the regular setup of 180k into diode then 15k, then 56k into 50k trimmer?