Looking for BIG power resistors
Steve
So far I've been able to use all of the original parts but some
of the bleeder resistors in the HV supply are bad. Hoping
someone has these in their junkbox;
25K ohm 80 watt; these are 11.5" long and 1.125" in diameter,
ceramic with cartridge type ends. Made by Groves Corp (bit this isn't
important). Need at least two of these.
The other resistor is really one of those old style ceramic floor
heater elements. It has wire wound on a ceramic cone and
uses a standard light bulb base. 220 volts, 660 watts.
This monster is put in series with the primary of the plate
transformer for "low power tuning". Chuckle...
Steve
Bill Noble
still available at some appliance stores (at least I've seen it there) and
also at swap meets- you can just replace the heating element if you like,
nichrome coils are readily available in various wattage/voltage
combinations.
If you want to try a surplus store, try ford electronics in fullerton CA -
they should have some of that kind of stuff - if I remember right the phone
is 714 521 8080
"Steve" <za...@sonic.net> wrote in message
news:4b020e6f$0$1992$742e...@news.sonic.net...
dave
sho...@trailing-edge.com
> I'm in the process of restoring a WWII vintage transmitter.
> So far I've been able to use all of the original parts but some
> of the bleeder resistors in the HV supply are bad. Hoping
> someone has these in their junkbox;
>
> 25K ohm 80 watt; these are 11.5" long and 1.125" in diameter,
> ceramic with cartridge type ends. Made by Groves Corp (bit this isn't
> important). Need at least two of these.
Not exactly original but ceramic tubular resistors are still made
today by Vishay, Bourns, etc.
See e.g. HL10006Z25K00JJ
For the same wattage the modern ones are probably a factor of two
smaller.
> The other resistor is really one of those old style ceramic floor
> heater elements. It has wire wound on a ceramic cone and
> uses a standard light bulb base. 220 volts, 660 watts.
> This monster is put in series with the primary of the plate
> transformer for "low power tuning". Chuckle...
Might want to think about a large-wattage 220V light bulb dropped in.
Light bulbs are interesting circuit elements, often usable on purpose
for the way the resistance increases as they heat up.
Tim.
GregS
>On Nov 16, 9:46=A0pm, "Steve" <za...@sonic.net> wrote:
>> I'm in the process of restoring a WWII vintage transmitter.
>> So far I've been able to use all of the original parts but some
>> of the bleeder resistors in the HV supply are bad. Hoping
>> someone has these in their junkbox;
>>
>> ceramic with cartridge type ends. Made by Groves Corp (bit this isn't
>> important). Need at least two of these.
>
>Not exactly original but ceramic tubular resistors are still made
>today by Vishay, Bourns, etc.
Ohmite.
I just bought a 225 watt 2.5K last week from Allied.
greg