>Arsk0jn wrote:
>> You can measure the reactance of a resistor if you have two that are very
>> close to the same resistance value with either a grid-dip meter or
MFJ-259...
>
>I didn't go through Joe's solution, but out of curiosity I decided to try
>to measure the inductance of some Xicon 51-ohm, 5W metal oxide resistors
>that I got from Mouser. The one I grabbed out of the box measured 50.3
>ohms.
>
>To test, I added silver-mica capacitors of several values in series (keep-
>ing leads as short as possible), and used my MFJ259 to measure the resonant
>frequency with each. Knowing that frequency, I calculated the reactance of
>the capacitor, and using that reactance calculated the inductance of the
>resistor.
>
>Here's what I got, and I don't mean to imply by the number of significant
>digits that I can measure that accurately. You'll need to use a fixed-
>width font to see what I'm seeing:
>
>CAPACITOR FREQUENCY REACTANCE INDUCTANCE
>--------- --------- --------- ----------
>148.0 pf 57 MHz 18.9 ohms 52.8 nH
> 50.2 pf 100 MHz 31.7 ohms 50.5 nH
> 26.8 pf 135 MHz 44.0 ohms 51.9 nH
>
> Average= 51.7 nH
Interesting, Jon. Thanks. . 50nH seems like a bit much intrinsic L for
use in a vhf suppressor. If you are interested in making a comparison, I
will mail you some Matsushita resistors that appear to have less
intrinsic L. If you e-mail me your snail-mail address, you should have
the resistors in a few days.
- later
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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