They are healthy. If you got any 6N2PEV that can show better voltage drop match between sections, maybe could be even better. But gain matching between channels is all that matters in the end. So wait for that test before changing tubes around.
What values in the divider now? Changed something there?
What values in the divider now? Changed something there?
No simple desolder & solder again the resistors in the voltage divider to be sure resistors values are both 470K, can I play LPs?
With what cart? Having input transformer? Check there is no dc on input for cartridge. Then put 300Hz test track on HFNRR test disc and DMM on AC. See that outputs show no more than 1-2dB difference for mV. Match best by swapping some 6N2PEV for best ACmv match between L&R.
Cart DL103R, Step-Up Partridge 977 6:1, there is no dc on input cart in both channels.
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OK, SUT can't pass DC to cartridge. Do the channels best output matching test. It will include the cartridge channel difference due to windings, alignment by manufacturer, and anti skating, will not be perfect, but look for no gross differences and try for best input tubes for near AC mV on each output between channels. If you have 0.5mV from a generator give 300Hz sinewave so its only the electronics error.
I had bought some a year or more ago from some guy in Ukraine, he was on ebay. Igor, Sergei, something. He had lot of those and red army capacitors pio, teflon.
Yes, now I have a true RMS dvm, OK set sinewave 300Hz 0,5mV, only to be sure without the SUT, right?
The scope shows one channel more gain than the other, Not a perfect sine wave I suppose is due to the fact of the RIAA or the SUT, right?
No perfect sine because no RIAA pre emphasis on the generator. Its not a vinyl record or anti-Riaa filtered.
Range 600mV
Resolution 01.mV
Accuracy +-1.0% of rdg + 6 digits
Range 6V
Resolution 1mV
Accuracy +-0.8% of rdg + 3 digits
Resolution 01.mV
Accuracy +-1.0% of rdg + 6 digits
Range 6V
Resolution 1mV
Accuracy +-0.8% of rdg + 3 digits