【Overview】 ・This item is a repair and restoration of a junk item from approximately 50 years ago. Although the normal operation of all functions has been confirmed many times, it is being sold as a junk item due to its age. Due to the recent increase in return scams, we are very reluctantly unable to accept returns. Except for complete non-functionality, please understand that no claims or returns will be accepted. As an exception, we will provide free repair if you cover the round-trip shipping costs. 【Product Description】 Product: Stereo Cassette Deck Manufacturer: Sony Model Number: TC-K4 Release Date: 1976 Price: 59,800 yen 【Appearance】 ・The front panel is almost free of scratches and is clean, but there were several very slight rust spots on the body, which have been removed and repainted. Considering its age, it is in almost excellent condition. 【Repairs and Adjustments】 ・Complete disassembly and cleaning of the front and rear drive sections, and grease application ・Complete disassembly and cleaning of the head block, and repair ・Cleaning of recording and playback volume controls with ethanol ultrasonic cleaning ・Complete disassembly and ethanol ultrasonic cleaning of the record/playback switch ・Replacement of capstan, auto shut-off, and counter belts ・Repair of auto shut-off and cassette loading mechanism ・Repair of the first-stage amplification circuit, the mid-stage amplification circuit, and the Dolby circuit ・Adjustment of the electronic control motor speed ・Adjustment of playback, recording, VU meter sensitivity, and head azimuth ・Cleaning of the record/playback head, pinch roller, and capstan 【Operation Check】 ・All functions have been tested and confirmed to work, including recording, playback, pause, fast forward, rewind, and timer standby functions. 【Sound Quality Check】 ・Based on listening tests with commercially available music tapes, the sound quality is sufficient for enjoying music as a cassette deck that is approximately 50 years old (wow and flutter 0.18%) (recording and playback may be poor depending on the tape's storage condition). 【Included Accessories】 ・One test tape used for recording, playback operation check, and adjustment 【Important Notes】 ・Please use the device for only 1-2 hours a day, as the resin parts have deteriorated over time and may cause malfunctions. ・The playback speed (pitch) can be finely adjusted with the semi-fixed resistor in the servo motor circuit, but it requires opening the chassis.