[Amps] 47 Ohm 5 watt

[Richard Solomon]

I usually parallel 3 150 ohm
1 or 2 watt AB carbons.

73, Dick, W1KSZ

On Sat, Aug 11, 2018 at 9:46 AM, Joe <nss at mwt.net> wrote:

> Yeah temp would be an issue, these will  be replacing these in a SB-220
> amp.
> Joe
>
> Sig
> The Original Rolling Ball Clock
> Idle Tyme
> Idle-Tyme.com
> http://www.idle-tyme.com
> On 8/9/2018 12:54 PM, Bryan Swadener via Amps wrote:
>
>> Be careful of the temperature derating. The datasheet says they start to
>> derate at 25°C and derate to zero at 155°C. Caddock and others produce
>> similar power resistors.  Kanthal/Globar produces suitable single units
>> but, I've not heard of a source for small quantities.  However, a coupla
>> 100Ω/2W carbon composition resistors can be used in parallel. Ebay seller
>> 'bigsmythe74' has new old stock Allen-Bradley but, he wants $4/each.
>> Sorting by price, I see he has 91Ω/2W available for $1.25 each (
>> http://www.ebay.com/itm/400003772794). Add $3.50/order shipping to USA.
>> vy 73,  Bryan WA7PRC
>>
>> ----------------------------------------------------------------------
>>
>> Date: Wed, 08 Aug 2018 16:50:37 +0000
>> From: Manfred Mornhinweg <manfred at ludens.cl>
>> To: amps at contesting.com
>> Subject: Re: [Amps] 47 Ohm 5 watt
>>
>> Joe,
>>
>> I hope someone has in their parts box. (2) 5 Watt 47 ohm non inductive
>>> resistors.
>>>
>> Actually I do have a few, apparently metal oxide, but shipping them to
>> you would cost more and take much longer than if you buy them...
>>
>> Maybe you can use this one:
>>
>> https://www.digikey.com/product-detail/en/ohmite/TNP10SC47R0
>> FE/TNP10SC47R0FE-ND/6165413
>>
>> It's 10W, but still small enough and not too expensive. You can either
>> bolt it to the chassis, or on a little aluminium sheet that acts as
>> heatsink, shaped and bent to fit the space you have. These resistors
>> have lower inductance than old-style "non-inductive" ones, due to their
>> smaller size. Of course you destroy that advantage if you have to use
>> long wires to connect them...
>>
>> Or you can assemble them from several 2W film resistors of properly
>> chosen values, combined in parallel. Those are very common and
>> inexpensive. Or use a bunch of even smaller resistors.
>>
>> Manfred
>>
>> ========================
>> Visit my hobby homepage!
>> http://ludens.cl
>> ========================
>> _______________________________________________
>> Amps mailing list
>> Amps at contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>