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Old 16th Jul 2019, 9:40 pm   #12
Mike. Watterson
Heptode
 
Join Date: Dec 2014
Location: Limerick, Ireland.
Posts: 901
Default Re: Ultra 761. Actually a T671.

20% often fitted and valve circuits can tolerate even 50%, except for cathode resistors or battery set HT- bias resistor, which indeed 10% is better.

The 68K reading 106K may or not matter depending where it is. If it's the Local Oscillator HT feed, then indeed it's too high. It doesn't much matter for a grid resistor.

Older resistors
No band = 20%
Silver = 10%
Gold = 5%

Newer resistors
green = 5%
red = 2%
brown = 1% (there is usually an extra value band, so Red, Yellow, Black, Orange, Brown = 270K 1%)
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