Day Sequerra FM Reference Scope Repair Completed
I recently listed my Day Sequerra FM Reference Tuner with a bad scope tube here and over at another auction place. After the winning bidder failed to pay, I was actually glad because I was having sellers remorse and decided to keep it. Since I'm keeping it, I figured I would put the time into fixing the scope.
Contrary to what was listed here, it is possible to fix the scope. After removing the scope tube, determining the size and pinout, putting some time into researching it and making a few phone calls, I determined the exact part number for the current scope tube as well as two equivalent tubes. Based on the pin numbering on the PCB, one of the equivalents is most likely what the FM Reference was originally designed for since they match up. After picking up two tubes (one new and one used but good), my FM Reference is again fully functional.
I was also able to determine three reasons that these tubes burn out at such a high rate. One is easily corrected and it really helps with the second one. The third is an issue with the tube itself.
If anyone is in a similar situation, let me know and I'll see what I can do to help (besides selling my spare tube). I took pictures of the process, so if I get some time and there is interest I'll put something together.