05-03-2017, 06:40 AM
OK, so I have found a schematic for the radio (Photofax) and have located the rectifier tube (either a 35Z5GT or a 35Y4), and the output tube ("Power Output" in the documentation - 50A5 or 50L6GT). I'm assuming that since my problem is occurring after running the radio for a few minutes that I need to test the tube when it is "warm".
What would the best way to do this ? Run the radio outside the case for 5-10 minutes. Unplug, remove tube and test, or run the test on the cold tube and essentially have it run in the tube tester for 5-10 minutes. The later will require me to hold the test button down on the tester for that length of time. Neither is a big deal, but just asking in case one make more sense than the other.
Also if I need to go so far as checking the resistors R101 and R102 what exactly do I need to do ? Am I just checking the resistance ? Can I do this while they are still soldered to the chassis or do I have to remove them ? Also in my document there is nothing that shows R101, R102 so I am not sure which resistors you are referring to.
Sorry for the rather basic questions, I am inexperienced at doing this type of work, but would like to learn (safely of course)
What would the best way to do this ? Run the radio outside the case for 5-10 minutes. Unplug, remove tube and test, or run the test on the cold tube and essentially have it run in the tube tester for 5-10 minutes. The later will require me to hold the test button down on the tester for that length of time. Neither is a big deal, but just asking in case one make more sense than the other.
Also if I need to go so far as checking the resistors R101 and R102 what exactly do I need to do ? Am I just checking the resistance ? Can I do this while they are still soldered to the chassis or do I have to remove them ? Also in my document there is nothing that shows R101, R102 so I am not sure which resistors you are referring to.
Sorry for the rather basic questions, I am inexperienced at doing this type of work, but would like to learn (safely of course)