HK 330A Repair and Restore
Here is a cause for celebration. My first Harmon Kardon. Pictures at the end.
I think I will repair and restore this one. Nice shape cosmetically. Works other than right channel distorted. Couple of dial lamps and meter lamp out.
I think I will first replace the eletrolytic capacitors in the power supply and the main board, along with the DC balance and bias trim pots, then see about transistors. Probably do the electrolytic capacitors in all the other boards, as well.
Interesting how the power supply is spread around.
There is no handy "parts list" for these at least I can see from the service manual on HiFi Engine. Schematic appears hand done. Boards are silk screened but no lead or polarity orientation indicators. I better pay attention when the time comes. Make notes and markings.
I made an electrolytics parts list from the schematic for the main board and power supply and have begun to compare power supply spec to actual. Looks like power supply C914 identified on the schematic as 2200uF 35V takes the form of two 1000uF 35V in parallel on the underside of the board upper right-hand corner -- is that right -- space reasons I am guessing.
C918 located top side near big cap is supposed to be 220uF 25V and looks to be 1000uF 35V.
How about the full-wave rectifier, IS-1850. Inclined to leave it alone unless prone to degrade.
Ah well. This is going to be interesting. Any thoughts or suggestions, please let me know.
As near as I can tell serial #7225979.
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