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NKMa (1) Voltages and (2)Grounding strap
Author: Ron Sweet
Date: 10/19/2013
Please refer to the following two photos:

http://ronsweetmusic.com/nkma/NKMa%20SN% 201282%20Main%20board.jpg

http://ronsweetmusic.com/nkma/NKMa%20SN% 201282%20Daughterboard.jpg

Filament voltage under load (KM56) reads 3.9V at the normal tap point (see point #2 in Main Board photo). First question is whether 3.9V is high enough. If not, then is there any reason I can't feed the filament with 4.1V from point #1 in the photo, and eliminate the need to swap out the appropriate resistor? And if it's better to swap resistors than use point #1, which resistor is the one to swap, since the resistor numbering on the daughterboard doesn't match that in the schematic that I have? Is it R2 in the daughterboard photo?

Finally, is there any reason why I can't replace the missing ground strap with a piece of solid copper wire? If the strap is advisable, where can I get one?

FYI, plate voltage under load is 119V.

Thanks in advance,

Ron  
 
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