[Heathkit] SB 200 and 220 HV meter resistor source

[jeremy-ca]

This may have been covered before but I keep getting questions about it.
As we all know, the 4.7 meg 1W carbon resistors used are operated well above 
their voltage ratings and increase way up in value over the years. These 
cause low voltage readings often resulting in owner stress thinking his PS 
is on the way out.

Ohmite has a 2.5KV rated 15 Meg 1 % resistor that is well within the 
tolerance range of the originals. Mouser has this at $5.14   their Part # 
588-MOX-400231505FE

Mouser has other parts for the amp power supplies including 1N5408 diodes to 
replace the well aged 600PIV originals, CDE 381LX series electrolytics and 
75-100K 5W MOX  resistors to replace the electrolytic balancing heat 
generators. I also use 1N5408's to replace SB220 blown bias zeners; they are 
bulletproof to tube arcs.

Carl
KM1H
Amplifier Repairs and design since 1963