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-   -   Looking for BIG power resistors (https://www.radiobanter.com/equipment/148020-looking-big-power-resistors.html)

Steve November 17th 09 02:46 AM

Looking for BIG power resistors
 
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.

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 November 17th 09 04:32 AM

Looking for BIG power resistors
 
the big resistors are common at swap meets here, and the heating element is
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" wrote in message
...
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.

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


dave November 17th 09 01:30 PM

Looking for BIG power resistors
 
Bill Noble wrote:
the big resistors are common at swap meets here, and the heating element
is 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" wrote in message
...
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.

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


[email protected][_2_] November 17th 09 03:23 PM

Looking for BIG power resistors
 
On Nov 16, 9:46*pm, "Steve" 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;

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[_2_] November 17th 09 04:20 PM

Looking for BIG power resistors
 
In article , " wrote:
On Nov 16, 9:46=A0pm, "Steve" 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;

25K ohm 80 watt; =A0these 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.



Ohmite.

I just bought a 225 watt 2.5K last week from Allied.

greg

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.



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