Help with troubleshooting Ming Da MC34-AII

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Hi,
I'm troubleshooting this amp for an aquaintance. This is not the schematic of the amp. The front end is similar but the output tubes are dual triode 6N5s. Left channel was working and no sound from the right. I found that the 100K plate resistor on the input tube 6N2 was open. I measured the working channel's plate resistor and it measured 210K ohms. The color code on the resistor says 100k but it measured 210K. I replace the bad resistor with a 210k resistor and the amp seems to work fine. So my question is should I change both the resistors to 100k as shown on the schematic and as indicated on the resistor color code or leave it? What would I gain or lose with the change, if any? Any help would be appreciated. Also, this amp has two switches. One says power and the other says protective switch. What's the purpose of the protective switch?
One more question, the amp's 2A fast acting fuse would blow on turn on every once in a while . Would a slow-blow 2A or 3A fuse work instead?
Regards,
David

Edits: 07/03/15 07/03/15

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Topic - Help with troubleshooting Ming Da MC34-AII - Sidewinder 17:12:04 07/03/15 (10)

RE: Help with troubleshooting Ming Da MC34-AII - JKT 21:14:00 07/03/15 (4)

RE: Help with troubleshooting Ming Da MC34-AII - Sidewinder 01:23:00 07/04/15 (3)

RE: Help with troubleshooting Ming Da MC34-AII - JKT 10:49:07 07/04/15 (2)

RE: Help with troubleshooting Ming Da MC34-AII - Sidewinder 13:01:51 07/04/15 (1)

RE: Help with troubleshooting Ming Da MC34-AII - JKT 15:58:32 07/04/15 (0)

Did you pull one leg of the resistor before measuring them? (n/t) - FenderLover 18:14:20 07/03/15 (4)

RE: Did you pull one leg of the resistor before measuring them? (n/t) - Sidewinder 19:21:14 07/03/15 (3)

grid-leak resistor - FenderLover 00:57:04 07/04/15 (2)

RE: grid-leak resistor - Sidewinder 01:26:49 07/04/15 (1)

fuses - FenderLover 07:45:33 07/04/15 (0)

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