If you had carbon or debris from burn or blow up partsnear the pcb and screws, I would change the whole pcb, if it's burned it's no longer good
Guys good morning
Thank you very much for you suggestions and observations.
The psu continues to work flawless and the preamplifier is now in another tier.
As you can see from the pics its completely dual mono and the b+ and the filaments has been completely separate PSUs for each channel.
I have a question
We have 4 transformers 2 in each channel all power up with the same mains switch on the front unit. I have read the its not good for the tubes the b+ and the heaters power up at the same time. So because i dont want to mess up with delay boards and too complex soldering (remember what happened with the diodes problem i had) can i put a second mains switch seperate from the heaters because i have the advantage of separate transformers for hv and lv and power on heaters first and after a couple of seconds the hv or leave it as it is now in the risk of starting a fire again?
I forgot to tell you that the second transformer at each channel is output 15v ac for the preamplifier heaters and then goes to diodes🔥😆😆😆caps and 7812 SPARKOS regulator and 6.3 v ac connected directly unregulated to the ECL82 tube HEATERS.
Is it safe then if i go with the 2 mains switches to power up the heaters transformer first but the ecl82 will have the heaters on but no hv to regulate which is coming next after i power on the hv transformer?
Thank you very much for you suggestions and observations.
The psu continues to work flawless and the preamplifier is now in another tier.
As you can see from the pics its completely dual mono and the b+ and the filaments has been completely separate PSUs for each channel.
I have a question
We have 4 transformers 2 in each channel all power up with the same mains switch on the front unit. I have read the its not good for the tubes the b+ and the heaters power up at the same time. So because i dont want to mess up with delay boards and too complex soldering (remember what happened with the diodes problem i had) can i put a second mains switch seperate from the heaters because i have the advantage of separate transformers for hv and lv and power on heaters first and after a couple of seconds the hv or leave it as it is now in the risk of starting a fire again?
I forgot to tell you that the second transformer at each channel is output 15v ac for the preamplifier heaters and then goes to diodes🔥😆😆😆caps and 7812 SPARKOS regulator and 6.3 v ac connected directly unregulated to the ECL82 tube HEATERS.
Is it safe then if i go with the 2 mains switches to power up the heaters transformer first but the ecl82 will have the heaters on but no hv to regulate which is coming next after i power on the hv transformer?
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If I understand you right, you are measuring and comparing voltages with a cap and without a cap, so in the first case you measure amplitude, in the second case an average rectified voltage?
A DCV meter always reads average DC.
Without a smoothing cap the voltage consists of rectified half-cycles meaning lower average DCV.
The cap stores charge and (more or less depending on cap value and loadcurrent) fills up the valleys between between the half-cycles, so average DCV increases.
Without a load current the cap charges to a DCV corresponding to the peak AC voltage and ripple voltage is zero.
