In replacing a large can capacitor in my McIntosh C24 preamp, I burned out a 2.2k, 1w, carbon resistor that was attached to the old cap. It will be next week before I can get the correct part, but I'm very close (I think) to getting the unit operational and I don't want to wait for the part. I stopped by a Radio Shach and purchased two alternatives: 1) a 2.2k, 1/2 w carbon film, or 2) I can string together two 1k, 1w, plus two 100 ohm, 1w, medal oxide resistors. (1k + 1k + 100 + 100.) This would be a temporary fix until I get the right component.
I'd appreciate thoughts on which to use.
Thanks
I'd appreciate thoughts on which to use.
Thanks
1) No. McIntosh didn't use a 1 W resistor just for fun, so you're 1/2 W resistor might be overloaded.
2) Yes, this should work.
Since power is dissipated in four resistors instead of one, they might even be less than 1 W. For the 1k resistors, 1/2 W should suffice, for the 100R resistors 1/8 W is sufficient.
3) Yes, if the power the 2k2/1W resistor was designed to dissipate is somewhat less than 1 W (likely), this should work.
Because of tolerances, currents flowing through the parallelled resistors, aren't equal. Though, this is of little concern if the actual dissipation in the 2k2/1W resistor is not very close to 1 W.
2) Yes, this should work.
Since power is dissipated in four resistors instead of one, they might even be less than 1 W. For the 1k resistors, 1/2 W should suffice, for the 100R resistors 1/8 W is sufficient.
3) Yes, if the power the 2k2/1W resistor was designed to dissipate is somewhat less than 1 W (likely), this should work.
Because of tolerances, currents flowing through the parallelled resistors, aren't equal. Though, this is of little concern if the actual dissipation in the 2k2/1W resistor is not very close to 1 W.
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yes you are correct.
but if you parrallel 2.2k with 2.2k both 1W you end up with a 1.1kohm 2W resisitor.
add the same up again and series and 2.2k higher wattage....
This reminds me of the; If you had a 5 and a 3 gallon bucket how do you measure out 4 gallons of water?
Not at all suggesting using a lesser rated part, but out of curiosity (because sometimes there are other constraints or desires) is it possible to post a partial schematic or sketch of how this 2.2K resistor is used?
Just re-read your original post where it seems possible this resistor is a bleeder across the large bulk cap, this would dissipate approximately half its rating for a 33V supply, or maybe its just part of a shunt regulator.
Many thanks
-Antonio
Not at all suggesting using a lesser rated part, but out of curiosity (because sometimes there are other constraints or desires) is it possible to post a partial schematic or sketch of how this 2.2K resistor is used?
Just re-read your original post where it seems possible this resistor is a bleeder across the large bulk cap, this would dissipate approximately half its rating for a 33V supply, or maybe its just part of a shunt regulator.
Many thanks
-Antonio
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Whoops... my remark in 3) about not being to close to 1 W is not applicable when 1/2 W resistors are being used. It would be in case of 1/4 W resistors.
The division of power dissipated I wrote about in 2) obviously also applies to 3).
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Wanders, Thanks for the attachment.
Dont know what the actually current is but just based on the 1/16A fuse one would assume less than 12mA ( factor of 5 fuse derating). This would dissipate .32W if all is working correctly (so I would agree that a 1W seems reasonable).
Thanks
-Antonio
An externally hosted image should be here but it was not working when we last tested it.
It's a fast-blow type, some serial numbers have a solder-in pigtail type, others have a snap-in cartridge type.
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