Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dbishopbliss on June 28, 2023, 08:23:48 am
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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.
(https://i.ibb.co/hYTzm5p/image.png) (https://ibb.co/mNPWcsQ)
imagehosting (https://imgbb.com/)
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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.
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Its supposed to look like this but the brown band has faded over time.
(https://external-content.duckduckgo.com/iu/?u=http%3A%2F%2Fwww.goldeno.com%2Fpictures%2FImg14117.JPG&f=1&nofb=1&ipt=7330caa41f94eb3428dc375556d78328d1721d87b0203d5826ab8272d6897bb1&ipo=images)
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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.
(https://external-content.duckduckgo.com/iu/?u=http%3A%2F%2Fwww.goldeno.com%2Fpictures%2FImg14117.JPG&f=1&nofb=1&ipt=7330caa41f94eb3428dc375556d78328d1721d87b0203d5826ab8272d6897bb1&ipo=images)
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There is no space for that brown band between the other bands
I misunderstand
Franco