Hello all,
I am in the process of building a Tubelab Simple SE. I have the amplifier wired up, and both channels plays music nicely 🙂
One problem, however: The amp only functions in solid state rectifying mode.
When I switch to tube recitifying, I measure some strange voltages on the T1-YEL pins: 163 volts AC, and there are no B+. This happens with or without the tube rectifier inserted...?!
This is a little beyond my capabilities, since I am a total noob as far as tube amp building goes. Can anybody come up with any suggestions to the cause of this, and/or things I can try out?
Any help will be greatly appreciated 🙂
Morten
I am in the process of building a Tubelab Simple SE. I have the amplifier wired up, and both channels plays music nicely 🙂
One problem, however: The amp only functions in solid state rectifying mode.
When I switch to tube recitifying, I measure some strange voltages on the T1-YEL pins: 163 volts AC, and there are no B+. This happens with or without the tube rectifier inserted...?!
This is a little beyond my capabilities, since I am a total noob as far as tube amp building goes. Can anybody come up with any suggestions to the cause of this, and/or things I can try out?
Any help will be greatly appreciated 🙂
Morten
I realise that my previous post may sound somewhat confusing, but that's because I myself am confused :-(
I shall try to be a little more precise:
With or without the rectifier tube I can measure
1) 5 volts between the T1- YEL terminals
2) 163 volts between one of the T1-YEL terminals and ground; 5 volts less between the other terminal and ground.
Is this normal? I can not from reading the schematics figure out how I end up having these voltages at the 5V filament terminals.
Morten
I shall try to be a little more precise:
With or without the rectifier tube I can measure
1) 5 volts between the T1- YEL terminals
2) 163 volts between one of the T1-YEL terminals and ground; 5 volts less between the other terminal and ground.
Is this normal? I can not from reading the schematics figure out how I end up having these voltages at the 5V filament terminals.
Morten
Which power transformer are you using? Make & model number.
Did you populate D3 & D4 on the board with diodes and TR1 with the proper thermistor?
If yes, did you verify proper polarity for the diodes?
Did you populate D3 & D4 on the board with diodes and TR1 with the proper thermistor?
If yes, did you verify proper polarity for the diodes?
The power transformer is a Hammond 374BX wired for 230V.
As for the D3 and D4 diodes and TR1 thermistor, the short answer is: no...
The slightly longer answer is: no, because George's assembly manual and parts list does not mention them 🙂 Anyway, I will grab some 1N4007s + a thermistor tomorrow and try it out, and with a little luck all will be ok then 🙂
Thanks for the reply!
As for the D3 and D4 diodes and TR1 thermistor, the short answer is: no...
The slightly longer answer is: no, because George's assembly manual and parts list does not mention them 🙂 Anyway, I will grab some 1N4007s + a thermistor tomorrow and try it out, and with a little luck all will be ok then 🙂
Thanks for the reply!
Problem solved🙂 Tube rectifying now works, and music is flowing...
And boy, does it sound great... I have the amp running in triode mode, so i still have both UL and CFB to look forward to. Yay...
Thanks again 🙂
Morten
And boy, does it sound great... I have the amp running in triode mode, so i still have both UL and CFB to look forward to. Yay...
Thanks again 🙂
Morten