you can swap in a 5U4 instead of the 5AR4.....warms up faster but drops more voltage
Yes, the 5U4g got me exactly where I wanted to be with a 4.7uf in C4 @ 280v. Just worried about cathode stripping, blah blah blah.
Relax......I may be using a 5U4 in my 45 version of the TSE...although it hasn't got nearly the miles on it as my 300B version.
You could also find a physically smaller 6H choke that has more resistance if you are married to the 5AR4.....or perhaps add resistance in series with the choke you have.
Also, although a bit tricky on the PCB you could add another RC stage to the power supply..this drops volts and noise too. Actually, you could add the additional RC stage off the board between the choke and C5. It would go choke, new cap to ground, resistor, then C5.
You could also find a physically smaller 6H choke that has more resistance if you are married to the 5AR4.....or perhaps add resistance in series with the choke you have.
Also, although a bit tricky on the PCB you could add another RC stage to the power supply..this drops volts and noise too. Actually, you could add the additional RC stage off the board between the choke and C5. It would go choke, new cap to ground, resistor, then C5.
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Jaybird: You have two things working against you on the power transformer....
The first one is that the actual voltage tends to run higher than the rated voltage for Hammonds, and the second is that your transformer is rated for 230ma and you are pulling about 80ma out of it, so it's loafing along. If you were to pull lots more current from the transformer the voltage would drop.......hard to do with 45's. One upside is that this transformer could easily drive 300B's in the TSE.
The first one is that the actual voltage tends to run higher than the rated voltage for Hammonds, and the second is that your transformer is rated for 230ma and you are pulling about 80ma out of it, so it's loafing along. If you were to pull lots more current from the transformer the voltage would drop.......hard to do with 45's. One upside is that this transformer could easily drive 300B's in the TSE.
Out of curiosity, which Variac are you using? Volt/Amp size? I've been looking at them but havent pushed the button yet.
Many thanks,
./e
Many thanks,
./e