In any case, old or brand new ones, an excessive current flow may break the
suppresor resistor or lead to derate its OHmic value until the flowing
current is decreased to an acceptable value for allowable dissipation.
The new ohmic value obtained may be not any more a proper one to have the
suppressor working as per design.
This point links directly to the original topic while the different
properties of aged carbon resistors much less..
73,
Mauri I4JMY
----- Original Message -----
From: Peter Chadwick <Peter_Chadwick@mitel.com>
To: <W8JI@contesting.com>; <amps@contesting.com>; <N6BUU@aol.com>
Sent: Tuesday, August 08, 2000 9:57 AM
Subject: RE: [AMPS] Suppressors, measurements, and acrimonious blather+
>
> Just to add further facts and cause confusion, I found a box of new (i.e.
> unused) 150Kohm, 1/4 watt, 5% carbon comps last night, said box being
dated
> 1974. I measured 10 resistors, and the worst one measured 151.5K ohm.
That's
> getting to within the accuracy limits of the DVM......
>
> A used 47k carbon film from the 1960's measured 47.5K, while a 50K, 10% of
1935,
> out of my old HRO, measured 55.6K.
>
> Makes me wonder if resistors have got worse
>
> 73
>
> Peter G3RZP
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