Skip, The easiest way to determine the oven resistor values for an unmarked tube is to directly measure the oven temperature and select a resistance to set it at the temperature you want. Your tube is a STD tube so I'd set it at 90 degrees C. Take a thermocouple meter and thermocouple and cut the junction off the end of the thermocouple. Attach a couple tiny alligator clips or grabbers. Next look at the potting around where the tubes cables come out. You should see short stubs of two different color wires peeking out of the potting. These are the ends of a thermocouple connected directly to the oven housing! I can't remember which type thermocouple it is. (I'll look in my notes and at the meter I use and let you know!) Connect the wires to your meter matching the color of the wires. Now with the tube cold you should see the ambient temperature on the meter. Power up the unit and you will see the temp start to rise. It will stabilize at the point determined by the resistance you selected. If too hot increase the resistance if too cold decrease.
Cheers, Corby _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.