Yamaha CR620
$200
Examples of interior restoration results (click on photos to expand)
Exterior photos
Restoration notes
Beyond the list of standard restoration steps detailed on the main page, here are some added notes for this unit :
I acquired this receiver a collector in the Grafton area. Full functionality claimed other than AM as dipole antenna missing. Exterior condition otherwise very good.
Replacement AM antenna obtained and installed.
Issue with signal strength meter debugged/fixed.
Noted “pop” in right channel when powering off. This was resolved with new protection relay.
Initial use of LEDs for tuner meters was not satisfactory (too directional) so installed new lamps instead.
Functional testing complete/passed. Enjoyed Yamaha “Natural Sound”.
Bench measurements
Yamaha specs amplifier power 2 ways :
40 watts per channel at 0.5% max distortion (both channels driven, 8ohms) at 1000Hz
35 watts per channel at 0.5% max distortion (both channels driven, 8ohms) from 20Hz -> 20,000Hz
My results :
41 watts per channel (8 ohms) at 0.5% distortion max, 1000Hz, both channels driven
35 watts per channel (8 ohms) at 0.5% distortion max, 20Hz -> 20,000Hz, both channels driven
Some reference links
hifiengine : https://www.hifiengine.com/manual_library/yamaha/cr-620.shtml
Classic Receivers : https://classicreceivers.com/yamaha-cr-620