[R-390] Tube Testers

[Glenn Little WB4UIV]

Your best tube tester is the instrument that you will be using the tube in.
If it works in the circuit, it is good.
Measure the voltages around the tube.
If they vary significantly from the manual, replace the tube.
If this fixes the problem, the tube was bad.
If the problem remains, put the original tube back in and find the 
bad capacitor, open coil or out of tolerance resistor.
Most of the resistors will be out of tolerance, high.
Any paper capacitors should be replaced with mylar or similar capacitors.
By definition, the paper capacitors are bad.




73
Glenn
WB4UIV
At 10:03 PM 9/16/2013, R. David Eagle wrote:
>Ok all my boat anchor enthusiasts!  I am preparing to restore my 
>first 390A.  My question to you all is what is a good universal tube 
>tester to have around and what would might be a good price?
>
>Thanks in advance...
>
>Dave
>kb8nnu
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