"Bill Turner" wrote in message
...
On Mon, 15 Mar 2004 10:46:53 +0000, Paul Burridge
wrote:

I've got quite a huge stash of inductors in my parts bin. The colour
codes don't always seem to relate to the values I've been able to
measure, with my multi-function DVM, however, and I can't accurately
measure any inductor about 10uH. Is there a circuit anywhere that
would enable me to get a reasonably accurate idea of the values I've
got down to say 100nH or thereabouts?

__________________________________________________ _______

I'd recommend a grid dip meter and a known capacitor, but be sure to
make the test at a frequency well below the self resonant frequency of
the inductor alone.

Another thing to be wary of: Some inductors are wound on a resistor to
reduce the Q for a specific purpose. Be suspicious of any which have an
unusually broad dip.

--
Bill, W6WRT
QSLs via LoTW


This is what I do; it works well even on my questionable dip meter.

Google for "LCR" meter; see what you come up with (mostly high $
instruments, probably).

On Mon, 15 Mar 2004 07:40:36 -0800, "Tim Wescott"
wrote:


Google for "LCR" meter; see what you come up with (mostly high $
instruments, probably).


This one is great:

http://www.aade.com/lcmeter.htm


John

On Mon, 15 Mar 2004 07:40:36 -0800, "Tim Wescott"
wrote:


Google for "LCR" meter; see what you come up with (mostly high $
instruments, probably).


This one is great:

http://www.aade.com/lcmeter.htm


John

Hi,

http://www.aade.com/lcmeter.htm

Or, as you have a counter, you could save yourself the money by
copying his oscillator and use a calculator to find the value of L
or C from the change in frequency.


Cheers - Joe

Hi,

http://www.aade.com/lcmeter.htm

Or, as you have a counter, you could save yourself the money by
copying his oscillator and use a calculator to find the value of L
or C from the change in frequency.


Cheers - Joe

This has been answered fairly often here before. You might try a
search. The AADE L/C Meter II does quite an adequate job down into
the nanohenry region, very quickly, for excitation at a few hundred
kHz, and for relatively little cost. For better info at specific
operating frequencies, try a vector network analyzer such as the N2PK
one I believe you already know about.

Paul Burridge wrote in message . ..
Hi all,

I've got quite a huge stash of inductors in my parts bin. The colour
codes don't always seem to relate to the values I've been able to
measure, with my multi-function DVM, however, and I can't accurately
measure any inductor about 10uH. Is there a circuit anywhere that
would enable me to get a reasonably accurate idea of the values I've
got down to say 100nH or thereabouts?

Thanks,

p.

This has been answered fairly often here before. You might try a
search. The AADE L/C Meter II does quite an adequate job down into
the nanohenry region, very quickly, for excitation at a few hundred
kHz, and for relatively little cost. For better info at specific
operating frequencies, try a vector network analyzer such as the N2PK
one I believe you already know about.

Paul Burridge wrote in message . ..
Hi all,

I've got quite a huge stash of inductors in my parts bin. The colour
codes don't always seem to relate to the values I've been able to
measure, with my multi-function DVM, however, and I can't accurately
measure any inductor about 10uH. Is there a circuit anywhere that
would enable me to get a reasonably accurate idea of the values I've
got down to say 100nH or thereabouts?

Thanks,

p.

On Mon, 15 Mar 2004 07:12:42 -0800, Bill Turner
wrote:

I'd recommend a grid dip meter and a known capacitor, but be sure to
make the test at a frequency well below the self resonant frequency of
the inductor alone.

I'm afraid my experience of using GDMs is *very* unfavourable. They
were fine in the days of big old HF kit, but nowadays with
PCB/surface-mounted stuff, they're *ucking useless.

Another thing to be wary of: Some inductors are wound on a resistor to
reduce the Q for a specific purpose. Be suspicious of any which have an
unusually broad dip.

ISTR some valve anode chokes used this arrangement in HF rigs a couple
of decades ago...

--

The BBC: Licensed at public expense to spread lies.

On Mon, 15 Mar 2004 07:12:42 -0800, Bill Turner
wrote:

I'd recommend a grid dip meter and a known capacitor, but be sure to
make the test at a frequency well below the self resonant frequency of
the inductor alone.

I'm afraid my experience of using GDMs is *very* unfavourable. They
were fine in the days of big old HF kit, but nowadays with
PCB/surface-mounted stuff, they're *ucking useless.

Another thing to be wary of: Some inductors are wound on a resistor to
reduce the Q for a specific purpose. Be suspicious of any which have an
unusually broad dip.

ISTR some valve anode chokes used this arrangement in HF rigs a couple
of decades ago...

--

The BBC: Licensed at public expense to spread lies.

On Mon, 15 Mar 2004 08:10:02 -0800, John Larkin
wrote:

On Mon, 15 Mar 2004 07:40:36 -0800, "Tim Wescott"
wrote:


Google for "LCR" meter; see what you come up with (mostly high $
instruments, probably).


This one is great:

http://www.aade.com/lcmeter.htm

Crumbs! Thanks, John!
--

The BBC: Licensed at public expense to spread lies.