Ranex RX2350 portable radio
Small, portable radio powered by 2 AA cells or external 3 V power supply. 9 bands: FM, MW and 7 short wave ranges. Made likely around 2001.
Although it was working, there were few problems/reasons for opening:
- minor crackles when switching frequency ranges and changing volume - very likely washing in alcohol was needed
- low/high switch apparently not working
- some corrosion visible through battery compartment
- some curiosity
Samsung S1A0426C02 - monolithic integrated circuit designed for radio cassette tape recorders, clock radios and headphone radios.
Wide operating voltage: 2V - 8.5V and low power consumption (typ. 5.3mA at 3V).
I though this would be a digital synthesizer, but it turns out this is analog, capacitor-tuned radio using all-in-one FM/AM receiver + audio amplifier and completely separated frequency counter / clock module.
Low/high switch was not working because of broken (corroded) PCB trace that I've repaired using thin wire soldered on top. I was hoping that low/high switch would be selecting sensitivity for radio reception but it turns out it is just audio filter switch cutting higher frequencies.
Internal ferrite antenna was held by some of glue, looking like a wax at first, but somehow brittle - I've applied some hot glue to hold it back in place.
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