The front-end is disassembled for cleaning and inspection. This is were I generally begin. I have a
methodical approach, and generally work from the front to the back. My approach...
1) First, identify issues and repair. Get the unit running first.
2) Strip the case and face off the unit
3) Service/restore the front end
4) Tuner section is next (if its a receiver)
5) Then the power supply
6) The back end (amp section)
7) Last, the back panel, and associated input boards
All new capacitors are installed and the pots are treated with DeoxIt and tuner cleaner. Below you
will see the backside of the board before and after cleaning. The heavy layer of flux is removed
with acetone. The whole board is washed with a mild soapy water.
The trimmers form the output section are removed and cleaned. The plastic cap can be removed by gently prying it off. A drop of DeoxIt is applied and a
small strip of paper is slipped between the contact and the unit is worked back and forth a dozen time. The paper polishes the surface and removes the
oxidation. The cap is snapped back into place afterward... nice and clean.
The contacts on the relay are also cleaned up... first with narrow strip of
1500 sand paper. Fold the paper in half length wise, and slip it between the
contact. Gently apply pressure to close the contacts on the paper and pull
it through. Repeat two or three times.
Then a strip of plain paper is run between the contact. in the same manner
It put a mirror polished surface on the contacts.