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Hoffman Amps Forum image Author Topic: What is this resistor?  (Read 2051 times)

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Offline dbishopbliss

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What is this resistor?
« on: June 28, 2023, 08:23:48 am »
I think this may be a really stupid question, but what do the bands of this resistor say the value should be? It measures 0.781K on my Fluke. But the bands??? To me they look Gray Red White Gold but that would be 82G right?

By the way, it is being used as the cathode resistor from V1a on a Marshall JTM45-ish amp. The cathodes of the channels are usually shared. The other resistor (not shown) is 2.2K.


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« Last Edit: June 28, 2023, 08:28:45 am by dbishopbliss »
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Offline sluckey

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Re: What is this resistor?
« Reply #1 on: June 28, 2023, 08:35:15 am »
I can't tell what the multiplier band color is. But seeing that resistor right next to a 25V electrolytic suggests it is a cathode resistor for a small tube. So my best guess is it's supposed to be 820Ω.

Maybe Yeatzee has been changing resistor colors again.
« Last Edit: June 28, 2023, 08:37:56 am by sluckey »
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Offline mresistor

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Re: What is this resistor?
« Reply #2 on: June 28, 2023, 09:26:08 am »
Its supposed to look like this  but the brown band has faded over time.


10 Mil Spec 820 Ohm 5% 2W Carbon Comp Resistors

Offline dbishopbliss

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Re: What is this resistor?
« Reply #3 on: June 28, 2023, 09:44:27 am »

That makes sense. The amp sounds great. I was just trying to reverse engineer what was going on. It is supposed to be similar to a JTM45, but based on those values the split cathodes are more similar to a JCM800 I think.

Its supposed to look like this  but the brown band has faded over time.


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Offline kagliostro

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Re: What is this resistor?
« Reply #4 on: June 28, 2023, 03:58:15 pm »
There is no space for that brown band between the other bands

I misunderstand

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