On 4/28/2014 5:14 AM, N_Cook wrote:
Was it 82K or 100K ? Assuming no other info available other than from
the general circuit posistion and other marks of the model , could be
either 82K or 100K.
1/2 watt metal oxide resistor, overheated to totally discolour the bands
and then open circuit.
Scraping an axial line of the laquering off, failure at one end, and the
rest measures 100.9K to the point where the MO is blackened and rapidly
increases in resistance.
Taking readings per turn of the spiral along this axial line, ie
sampling, readings are 1.3K,16.8K,40.5K,63.5K, 94.5k.
Point to consider , as the R failed at an end rather than at the middle,
whether fusible type or manufacturing flaw, it was probably not heated
as much as a resistor that failed in the centre, ie normally the hottest
point as not heatsinked by the tails and solder etc.
I know ,sort of balance of probability-wise , from this data what value
I would select as a replacement. But not wishing to bias anyone else's
opinion, what would others reading this, opt for 82K or 100K ?


Nigel,

If you'd post the make, model and component location you might find
someone here with a schematic and could then know what the original
value is.

Regards,
Tim Schwartz
Bristol Electronics