It seems to me that this business of the resistors opening/going high etc is
a potential problem, since a perfectly stable amp can after a few years
develop parasitics just because the resistors get hot from normal operation
and then go either high resistance or open. I guess the use of 'Globar' type
resistors may well help in this respect, or even possibly the very old
fashioned solid carbon 5 watt jobs. However, there is a cost/availability
issue. Has anyone ever measured the resistance of the carbon rod in a D size
cell? I wonder if baking one at high temperature for a while could stabilise
the resistance, and then, if it's in the 20 to 30 ohm region, it could
provide a useful, relatively low inductance suppressor resistor.
Comments?
73
Peter G3RZP
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