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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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31st Jul 2021, 10:05 pm | #1 |
Hexode
Join Date: Aug 2009
Location: Liverpool, Merseyside, UK.
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Resistor Wattage?
Good Evening All,
Can someone please help by telling me the wattage of the 820R resistor in the photo? Will it be comfortable at 4W? Thanks.
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Geoff. (BVWS Member) |
31st Jul 2021, 10:27 pm | #2 |
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Re: Resistor Wattage?
It's a vintage carbon film resistor (used to be called 'cracked carbon' and/or labelled 'high stability'), made by Piher. I'm afraid it won't be comfortable at 4W. They certainly made them in 1/2W, 1W and 2W versions and possibly in smaller sizes too. But I don't think any were rated higher than that. I think yours is the 2W size, but I'd need to extract one from storage and measure it to be sure.
Cheers, GJ
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31st Jul 2021, 10:32 pm | #3 |
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Re: Resistor Wattage?
I agree with GJ looks like a 2 Watt'r
I think I would be using a nice 7W wire wound if it were to be dissipating 4W continuously. Cheers Mike T
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31st Jul 2021, 10:44 pm | #4 | |
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Re: Resistor Wattage?
Quote:
Crossed with Mike. John
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1st Aug 2021, 1:31 am | #5 |
Hexode
Join Date: Aug 2009
Location: Liverpool, Merseyside, UK.
Posts: 254
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Re: Resistor Wattage?
Thanks for that, I very much feared that might be the case.
Having searched through the thousands of resistors which I have in stock, unfortunately, I have nothing suitable. 820 ohms, although a prefered value, does not seem to be available as 7W or 10W W/W.
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Geoff. (BVWS Member) |
1st Aug 2021, 8:40 am | #6 |
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Re: Resistor Wattage?
That is a Radiospares 2W and No more.
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1st Aug 2021, 9:01 am | #7 |
Heptode
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Re: Resistor Wattage?
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1st Aug 2021, 11:54 am | #8 |
Hexode
Join Date: Aug 2009
Location: Liverpool, Merseyside, UK.
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Re: Resistor Wattage?
Brilliant, thanks Andy.
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Geoff. (BVWS Member) |