Those "New" Half-Size Resistors

David Root · Post by **David Root** » Wed Oct 21, 2009 6:14 pm

Anyone run into these? I ordered several different 1/2 watt resistors recently and some of them look like 1/4 watt size or even 1/8 W.

This is Mouser and DigiKey so I am sure they are correctly identified, but they look awful tiny to me. Are they for real and are there any caveats to using them compared to the old larger sizes?.

I usually apply at least a 2.0 service factor on rated wattage, i.e if the power disipated is 0.25 W I use at least a 1W rated resistor.

Structo · Post by **Structo** » Wed Oct 21, 2009 8:43 pm

There was a thread a while back about these.
Might try an advanced google search to find it.

David Root · Post by **David Root** » Wed Oct 21, 2009 8:50 pm

Thanx. I looked but didn't find anything. I'll try again.

Checked the specs at Digikey. Wonderful! as Dirty Harry used to say, These things are no good for plate loads according to Andy Fuchs. Guess what my application is. Duh.

Structo · Post by **Structo** » Wed Oct 21, 2009 9:59 pm

This was the thread I was thinking of, don't know if it helps but here it is.

https://tubeamparchive.com/viewtopic.ph ... df93c574c3

FYL · Post by **FYL** » Wed Oct 21, 2009 10:41 pm

These things are no good for plate loads according to Andy Fuchs.

Andy hasn't answered my questions re. the exact reference of the failed resistors, so the jury is still out on his open-R problems.

briane · Post by **briane** » Thu Oct 22, 2009 6:51 pm

Andy hasn't answered my questions re. the exact reference of the failed resistors, so the jury is still out on his open-R problems.

I spent a good deal of time on that thread after getting a batch of the 'useless rn65's'

I recall that thread stated it was the RN65's that were about half the size of the ones I (or you would have) got last year. They used to be about the size of carbons, now much smaller. The ones I got were also not shiny (ie flat surface treatment) like they used to be. Luckily I still have not run out of the older RN65's, but I have been scavenging every parts drawer or crook in the house. I am about out now.

Make sure you check what they will be shipping before buying. There are other brands of metal film, which might be considered preferable to the new RN65's from a longevity standpoint.

David Root · Post by **David Root** » Thu Oct 22, 2009 10:58 pm

Newark still has the real thing in RN65s, I got a dozen recently (100K).

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Those "New" Half-Size Resistors

Those "New" Half-Size Resistors

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Re: Those "New" Half-Size Resistors

Re: Those "New" Half-Size Resistors

Re: Those "New" Half-Size Resistors

Re: Those "New" Half-Size Resistors

Real RN65s