[Lowfer] Measuring inductors

[Ed Phillips]

rick kirby wrote:

> Thanks to Clint, John,Paul, Steve and Ed,
>You were all very helpful and I appreciate the quick responses.I put the
>General Radio , Boonton and Heath meters as a favorite search on E-bay. Ill
>have to keep my eyes open . In the meantime I think I have the parts to
>build up the soundcard LCR meter. It looks simple enough and wont cost me
>anything. 
> Thank you all on the crash course on inductor characteristics.The results I
>was getting with my little test oscillator make some sense now. I have only
>played with torroids up in the HF world and everything always worked out to
>my calculated
>values up there.The only torroid Ive wound on LF was the the one in my
>Ashlock loopfinal and that wasn't very critical and worked ok.
>
> Thank You All again
>
>              73
>                 Rick  "PBO"
>  
>
    The Heath QM is not very accurate but it is very convenient because 
of its light weight and 'burn out proofmess] compared to the Boonton, 
which is heavy and uses a thermocouple which is easy to damage and 
probably impossible to replace.  The frequency can always be measured 
with a counter or a receiver [I bring a sample of the signal out via a 
BNC connector] and it is probably accurate to better than +/- 5% on the 
capacitance/inductance dial.  If you can find one pick it up.  The one I 
have was picked up for peanuts at a swap meet many, many years ago so I 
have no idea what they might go for now.  I suspect there weren't very 
many built because a Q meter is sort of an exotic instrument for someone 
who hasn't used one.  I always start measuring with the Heath and then 
go on to the Boonton if I want more accuracy.  Often don't.

Ed

Something else which would be very useful is a set of the standard coils 
for the Boonton.  I've never seen any for sale.