Re: Restore a Beau Decca
Here are the results of the tests suggested by Techman:
What you should do is remove the valves, noting which is which and with your meter set on the lowest ohms range (200 ohms?) carefully and accurately measure the resistance of the heaters of each valve at the valve pins. Note and report these readings, also note the reading on your meter with the test leads shorted together and report this reading, as we’ll need to subtract this reading from the two readings of the heaters. At this sort of low resistance, the resistance of the meter and its leads etc. are important and depending on the meter could be around 0.3 to 0.4 ohms.
Resistance Valve A= 1.8 ohms
Resistance Valve B= 1.7 ohms
meter resistance = 0.8 ohms
So the dimmer valve does have a slightly lower resistance.
The table in the photo shows the results from the tests proposed by PJL.
I've also noticed that the cap can holding C47 and C48 is getting hot. Should I replace these straight away or do a few power cycles to see if it recovers?
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