>Tom Rauch wrote:
>>I just received sample 5 watt metal film resistors from Mouser, as
>>per the conversation with Carl.
>>
>>The measured inductance of two 51 ohm resistors with nearly zero lead
>>length was 47.1 nH and 49.3 nH.
>>Both resistors are wound with about a five turn spiral of metal film
>>inside the case.
>
>Guessing at the length and diameter of a 5W resistor and using Tom's
>estiamte of "about five" turns, the usual formula for the inductance of
>a solenoid gives results somewhere in the right area. I wonder how well
>it works with the actual dimensions?
>
>Could you run a ruler over the resistors, Tom, and give us a better
>estimate of the actual number of turns?
>
The two end-caps amount to a shorted turn, which presumably obviates the
"usual formula".
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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