Ok, I need some help. When Kegger and I worked out this schematic he marked a couple resistors with watts and said the rest were .5 w or 1w or something like that. What watt should they be? P s, I added the 1W for the ones I dido know about.
location value value
Resistors
2 R2 220 1w
2 R3 1k 1w
2 R4 800 15w
2 R5 100k 1w
2 R6 22 1w
2 R7 22 1w
2 R8 510 1w
2 R9 510 1w
2 R10 68k 10w
Caps
2 C1 0.47 1000v
2 C2 50 200v
2 C3 220 10v
2 C4 47 ???
location value value
Resistors
2 R2 220 1w
2 R3 1k 1w
2 R4 800 15w
2 R5 100k 1w
2 R6 22 1w
2 R7 22 1w
2 R8 510 1w
2 R9 510 1w
2 R10 68k 10w
Caps
2 C1 0.47 1000v
2 C2 50 200v
2 C3 220 10v
2 C4 47 ???
Attachments
Straight power calculation is voltage times current. My experience is that resistors can fail below rating and for safe margin I usually double power rating at a minimum and up to 4x depending on the resistor.
The other important thing is voltage rating. I always plan for the voltage they are likely to see at some point in their career, not just the steady state drop across the resistor in normal operation. It makes for a lot of data sheet reading, (which is why for that past few years I've limited it to a small number of known manufactures and types) though I noticed in a search on Mouser yesterday that there was a (new, I think) voltage rating filter for through-hole resistors. That makes things a lot easier.
The other important thing is voltage rating. I always plan for the voltage they are likely to see at some point in their career, not just the steady state drop across the resistor in normal operation. It makes for a lot of data sheet reading, (which is why for that past few years I've limited it to a small number of known manufactures and types) though I noticed in a search on Mouser yesterday that there was a (new, I think) voltage rating filter for through-hole resistors. That makes things a lot easier.
No offence but are you sure you should be building an amplifier this lethal? 1kV of B+ is serious business and there are no second chances if you screw up.
I'm planning a GM70 build too and let me tell you, when that thing is in the building/testing phase I will be standing 2 meters away when the power goes on. Just solder cables when you want to measure something and stand back, don't go probing around.
Resistors also have a maximum voltage rating (often 200VDC-350VDC), don't approach this during operation.
Use several equal values in series, if necessary. Check in particular R10.
Inductors and transformers also have a maximum voltage rating.
Use several equal values in series, if necessary. Check in particular R10.
Inductors and transformers also have a maximum voltage rating.
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Two things to mention when i look at the schematic concerning the 12GN7A:
I would put a resistor from g1 to ground
and g3 should be connected directely to the cathode
I would put a resistor from g1 to ground
and g3 should be connected directely to the cathode