restore radio shack 53-555 duophone cordless electronic telephone


2010-02-19 11:23 pm
Analog based design, uniden japan interior parts and electronics.
I had to clean out turquoise encrusted patina caused by atmosphere contact onto cupris metallurgy posessing residual emf potential relative to earthing.
Onboard handset nickel cadmium battery trashed, won't accept base station's charging I think because the handset battery pack has internally exhausted functioning. So I ebay'd another that could fit (1/2 sized AA, three each series connect equals 1.2v x 3 = 3.6v) but I specified only nickel cadmium chemistry because I don't know how the base station supervises current control charging, you know "green band" of permissible current regulation for the battery chemistry and plate topology.
The web has nothing, so sad, no schematic.
So I replaced aluminium electrolytics that expired, unbelievably one in twelve, was bad, from the early '80's I had used this cordless phone, charming.
But I want to fix it so it works nice. I already fixed the hinge switch foldout mouthpiece, caig'g the encoding scheme and loudness power selecting switches, checked fwd voltage all junctions semiconductor diodes bjt's.
I powered up the handset with two D-size batteries series 3v and the led low charge earning light illuminates on handset. Ebay battery not arrived. I think 3v should allow testing with the base station transceive and utility carrier landline. It would be illegal to series three each D-size batteries.
Any help will be very appreciated, thanks in advance.