Resistor Question
F1nut
Posts: 50,566
Ok, so I've got some emitter resistors in an old SS amp that I need some help identifying.
Marked on two separate lines as follows;
M2 0.5ohm
Noble 02
They are axial with a white ceramic tubular body, which is about 5/8" long and 1/4" in diameter. Obviously they are 0.5 ohm and I think they are 2 watt, but I'd like to be sure. I called Noble who was absolutely no help, said they are too old. Is anyone familiar with these markings?
Marked on two separate lines as follows;
M2 0.5ohm
Noble 02
They are axial with a white ceramic tubular body, which is about 5/8" long and 1/4" in diameter. Obviously they are 0.5 ohm and I think they are 2 watt, but I'd like to be sure. I called Noble who was absolutely no help, said they are too old. Is anyone familiar with these markings?
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk
Post edited by F1nut on
Comments
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I am sure that you already googled the part number and had no hits....
I would go this way, as long as it's in the signal path and you know the voltage, you can calculate the wattage and current of the resistor and vice versa. base-emitter voltage is pretty much fixed and current will vary. I would use the max current of the transistor and use that value to calculate.
let's say the resistor is 2watt, then I would know the max voltage is 2V since P=V^2/R, then I would know that the max current would be 1A since P=V*I.Video: LG 55LN5100/Samsung LNT4065F
Receiver: HK AVR445
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Picture? What is the amp? Maybe we can find a schematic, service manual, or parts list.
If not, I'm sure there is some guidance out there (perhaps at DIYaudio) for sizing emitter resistors based on the output specific PNP/NPN transistors that are being used.For rig details, see my profile. Nothing here anymore... -
Hello,
Is this an Adcom GFA555 per chance?
Ken -
Sounds like a 5W emitter resistor, are they connected to a TO-3 transistor?Main System- Scratch built 2A3 , Lightspeed preamp, Technics SP15/Graham/XV1s,Klipschorns w/ALK xovers/Trachorns, Speakercraft MT8(4), Sonos ZP90, Yamaha Aventage for surround
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Thanks guys, I found the schematic. They are 0.5 ohm, 2 watt.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk
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