This is a typical power supply configuration for a tube device using silicon rectifier. Transformer with several windings, rectificaction, nice reservoir, Pi filter and RC stages. Two output windings, one is a 6,3V for the heaters and the other one is basically an insulating one for the HT. The binson is based in ECC83, does not need to get to messy with HT.
Transformer was OK, passed all testing with honours, wich is always a good relief. Took out the double caps and choke to inspect & check them.
Nice Sprague caps, after 50 years amanzingly still got acceptable capacitance, but awful ESR. The choke is not in its best days but gives good readings in all the tests. If finally the Echorec is restored I will take good care of the choke, for now it will be feasible for the initial device testing.
The caps were definitely out of the game in order to obtain an acceptable ripple, even though the choke would do a good job. It is difficult-impossible to find OMC replacements and in cases like this I always like to keep the original look as much as possible. So, the only way to go was to restuff the caps with new ones. Recapping can be a hard job, but really compensates the effort when it is well done. Check out the guts of this old boy:
Nice to see how it was manufactur with that rubber band holding everything and still in place. This is its new interior:
The other double cap followed the same process. I mounted them back, reinstall the choke and replace the carbon resistors. Afterwards, I was able to do some testing to the rejuvenated power supply, with and without load, getting pretty good results.
Next step is "updating" the cap-motor. I did some previous testing and it shows some minor problems.
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