WARNING!!!!! ACHTUNG!!!!!! VERY HIGH VOLTAGES!!!!!!! HOCH SPANNUNG!!!!! LEBENSGEFAHR!!!!!!! DANGER TO LIFE!!!!!!!!
Since we all just rent this equipment until it passes into the hands of other collectors, it makes sense to hand these radios down in better shape than they were before, or at lease in the same shape. Therefore I would like to start a sticky thread about radio repair best practices and about how to avoid destructive pitfalls.
WHEN YOU FIRST GET YOUR RADIO
1. Do NOT turn it on to see if it works.
2. Take all the tubes out.
3. Clean contacts with a good contact cleaning solution and a lint-free cloth.
4. Slowly increase filament voltage and measure on the filament termini.
5. Slowly increase anode voltage and measure on the anode terminus and ground.
6. Test the tubes on an RPG 4/3 (they are not very expensive these days and are usually available on Ebay)
7. Put the tubes back in, then slowly turn up the filament to CORRECT voltage. Filament being too low or too high is not good. Make sure the filament voltage is correct on the termini.
8. Turn up the anode voltage.
There is more freedom to vary the anode voltage depending on desired results/output, but filament voltage must be exactly what the tube specs dictate. If there is one worn-out tube that needs higher filament voltage, and you increase it, then you will dramatically shorten the life of the other tubes.
Yuri
Since we all just rent this equipment until it passes into the hands of other collectors, it makes sense to hand these radios down in better shape than they were before, or at lease in the same shape. Therefore I would like to start a sticky thread about radio repair best practices and about how to avoid destructive pitfalls.
WHEN YOU FIRST GET YOUR RADIO
1. Do NOT turn it on to see if it works.
2. Take all the tubes out.
3. Clean contacts with a good contact cleaning solution and a lint-free cloth.
4. Slowly increase filament voltage and measure on the filament termini.
5. Slowly increase anode voltage and measure on the anode terminus and ground.
6. Test the tubes on an RPG 4/3 (they are not very expensive these days and are usually available on Ebay)
7. Put the tubes back in, then slowly turn up the filament to CORRECT voltage. Filament being too low or too high is not good. Make sure the filament voltage is correct on the termini.
8. Turn up the anode voltage.
There is more freedom to vary the anode voltage depending on desired results/output, but filament voltage must be exactly what the tube specs dictate. If there is one worn-out tube that needs higher filament voltage, and you increase it, then you will dramatically shorten the life of the other tubes.
Yuri
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