Crossover distortion?
Got a Bambino-9 (9 what?) for £8.80 off ebay. It's all germaniums. Cleaned up nice. There were some dry joints and the black speaker/earphone wire was wrongly connected to the same node as the -ve battery... oops, that was probably me when I first got it a few months ago.
Reception is quite good, detachable telescopic aerial doesn't appear to make any difference.
Sounds very tinny and a bit clipped/distorted as if it has a broken speaker but it's the same on an earphone. Tried changing all electrolytics, no improvement. Tested with a tone modulated carrier. Nice sine waves at the bases of the output pair but that scope trace at the emitters. Also low and high tone frequencies lower the amplitude a lot.
Serial number 1001 suggests to me it might not have actually gone into production.
Is there likely to be a faulty component here or is this performance to be expected? Can that tinniness be improved by just dropping in a better (Si) replacement pair of output transistors?
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