More work on the Type 547 +100V PSU issue.
Sent Oculus a PM asking him to take some resistance readings on his Type 547 and he sent me the readings. Thank you! Here's the results.
PSU Supply My 547 His 547 Manual Spec
+225V to gnd 2.95K 2.76K 2K to 3K
+100V to gnd 1.397K 1.41K 1K to 2K
-150V to gnd 1.397K 1.58K 1K to 2K
Across +100V 2.184K 2.41K This is not specified in the manual
to -150V
If you notice my +100V and -150V readings are exactly the same which is very suspicious. I tried bd's idea of adding a 10K resistor across the -150V and it resulted in a change in the -150V reading as expected but the +100V reading changed by only a few ohms. So I think it's safe to say they aren't shorted together somewhere. But it still bugs me that they read the same right down to a few ohms.
When I swapped the 6080 regulator tube with the +225V supply the cathode resistors I replaced got red hot. So this 6080 tube must have been damaged when the short originally occurred. The filament lights up but there's no one home. Totally dead. I have replacement tubes coming tomorrow as long as USPS doesn't get lazy and fucks up.
![](https://imagizer.imageshack.com/v2/xq90/924/8yQkN9.jpg)
Going to spend the afternoon checking resistance values in both the +100V and -150V supplies. I'm hoping to stumble on something. We'll see.