skippy124 Posted September 1, 2012 Share Posted September 1, 2012 Hi, I posted this up on another forum, a thought I would share it here as well. I recently acquired a 771 in need of a little TLC. This receiver completed the series in my collection - 331 through to the 881 (we didn't get the 221 over here). It was stated as having low volume on all inputs, and was in need of a good clean. Once I had it opened up on the bench, a quick diagnosis showed that the only thing wrong was an intermittent source selector switch, a little di-oxit and the problem was resolved. She was a little dirty inside, but underneath the layer of dust and hair she is in pretty good condition. After a clean up Link to comment Share on other sites More sharing options...
skippy124 Posted September 1, 2012 Author Share Posted September 1, 2012 A view of the receiver from the top And underneath The case had some minor damage on the rear edge Some PVC Glue, Some clamps And the damage has been fixed Link to comment Share on other sites More sharing options...
skippy124 Posted September 1, 2012 Author Share Posted September 1, 2012 The front panel and knobs needed some attention Came up pretty good after a clean The rear panel was also needed some attention Before - After - Pretty happy with the final result. 1 Link to comment Share on other sites More sharing options...
skippy124 Posted September 1, 2012 Author Share Posted September 1, 2012 I was pleasantly surprised by the performance of this 771. I had previously thought that these were well under 30W per channel output, partly because of the 100W AC power consumption shown on the rear panel. A check of the specs in the service manual shows that these were in fact rated at 45W per channel, each driven @ 1khz into 8 ohms, and 40W per channel, both channels driven @ 1khz into 8 ohms. The actual power output figures that this amp achieved were 52.5W per channel, each channel driven, and 49.5W per channel, both channels driven. Very happy with that result!! Cheers John Link to comment Share on other sites More sharing options...
Sierra Posted September 1, 2012 Share Posted September 1, 2012 Nice find there. Fantastic job with the cleaning though ... how on earth did you clean it so well ... especially on the inside cleaning the circuit board and getting in between all the components? The front panel knobs and buttons look like they are brand new ... as do all the rear panel connectors. How did you get the oxidation off the rca connectors and the din plug without pulling it all apart? Kudos on your handywork Link to comment Share on other sites More sharing options...
Guest Muon Posted September 1, 2012 Share Posted September 1, 2012 (edited) I must say, I never get tired looking at these restro's by you and Pete, and others Edited September 1, 2012 by datafone Link to comment Share on other sites More sharing options...
skippy124 Posted September 1, 2012 Author Share Posted September 1, 2012 Nice find there. Fantastic job with the cleaning though ... how on earth did you clean it so well ... especially on the inside cleaning the circuit board and getting in between all the components? The front panel knobs and buttons look like they are brand new ... as do all the rear panel connectors. How did you get the oxidation off the rca connectors and the din plug without pulling it all apart? Kudos on your handywork I must say, I never get tired looking at these restro's by you and Pete, and others Thanks for the comments guys. The cleaning, although it can take some time, is one of the rewarding parts of doing a restoration. I use several methods, for internal cleaning to remove dust etc, a small paint brush used with care and a vacuum cleaner works wonders. For internals that are very dirty I use an orange oil cleaner (made for cleaning cables and electrical gear) and compressed air, an leave it our in the sun. I also use non ammonia Windex for front panel and knob cleaning, and a toothbrush comes in handy for the knobs and rear panel. I also use both silver and brass polishes (Silvo and Brasso) for final cleaning of metal knobs and for RCA connectors. Cheers John 1 Link to comment Share on other sites More sharing options...
Grainy Posted September 2, 2012 Share Posted September 2, 2012 (edited) I had one of these and gave it to a mate who inherited some 80's Polk 3 ways with some fancy tweeter. They sound so well together that it's now his main listening rig. Top resto job. You should have a show on 7Mate Skippy Edited September 2, 2012 by Grainy Link to comment Share on other sites More sharing options...
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