Unlike the short, glossy User Manual that came in the box (which only explains how to connect speakers and tune FM stations), the Service Manual is a technical bible. It is a factory-produced document intended exclusively for authorized Technics service centers.
A genuine service manual for the SA-370S contains:
Symptom: Left channel works; right channel sounds like a blown speaker (but it isn’t). Manual Solution: Check the PCB layout for the tone control board. Locate the notorious “orange drop” capacitors or the function switch relay. The parts list identifies which capacitors are in the signal path (e.g., C201, C202) so you can recap them with low-leakage Nichicon or Panasonic replacements. Technics Sa-370s Service Manual
The service manual tells you how the receiver works, but restoration wisdom comes from experience. Here are three pro-tips to accompany your manual:
Beware of scam sites selling low-resolution scans. Here are the best sources: Unlike the short, glossy User Manual that came
Search Tip: Use exact string searches: "Technics SA-370S" "service manual" filetype:pdf
The SA-370S is notorious for sticky function selector switches. The manual’s exploded view shows how to remove the front panel to access the rotary switches for DeoxIT cleaning without breaking the plastic push-button stems. Search Tip: Use exact string searches: "Technics SA-370S"
This is the most critical section. The manual will usually break this down into sub-sections:
Working on vintage receivers involves lethal mains voltages and high-current capacitors.