[Hallicrafters] What kind of resistors?

[Roy Morgan]

Quoting Bill Barfield <barfworks at bellsouth.net>:

> I have a couple of old units to restore that 600 to 700 volts running around
> in them and I may need to replace a few resistors. 
> 
> One good option might be the resistor kits sold by AES.  A kit of 1 watt
> carbon film resistors are 500v working and 1000v overload.

Don't be confused as to what the voltage rating is. That is the voltage from one
end of the resistor to the other end.  It's unlikely your resistors will have
to withstand over the 350 volts. A resistor may also be rated as to the
insulation it has, so if it is touching another part or wire.  Be sure you know
what the rating is.

Also, make sure you know where the 600  or 700 volts is running around at.  Most
such high voltages in, say, an HT-32 are for the final plate, and there won't
be two watt resistors from there to ground.

If you are using small wattage resistors (say 2 watters) as equalizing dividers
around electrolytic caps in series, you may wind up with 400 volts across one
resistance. Put two in series of half the needed value.  And pay attention to
the heat dissipated compared to the wattage.

Roy




Roy Morgan
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