12-10-2019, 03:50 PM
Check the voltages on the 42.
If you are testing prior to replacing the filters and all of the paper caps (in those blocks) you are probably just wasting time.
For the most part, you can assume that the tubes are good - unless you are running them with a missing screen voltage or too much DC on the grid - See: replace caps first. Either will toast an OP tube quickly - then the OP transformer or the PS transformer or both.
If you are testing prior to replacing the filters and all of the paper caps (in those blocks) you are probably just wasting time.
For the most part, you can assume that the tubes are good - unless you are running them with a missing screen voltage or too much DC on the grid - See: replace caps first. Either will toast an OP tube quickly - then the OP transformer or the PS transformer or both.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
