Fw: [Boatanchors] HeathKit QM-1 calibration question

Sat, 13 Mar 2004 20:13:42 -0600

Hello Luca,

Yes, Q meters have calibration measurement standards and some have
"working standards" to be used periodically to reconfirm accuracy. My
first question would be: What sort of accuracy are you looking for ? This
is a QM-1. The relative measurements are not affected, in other words you
can readily tell if one coil has a higher "Q" than another and that's
usually sufficient. If you did have "some standards", you would still
have correlation problems with someone else who had "some standards".
I've been through this.

My best recommendation is for you to wind some STABLE coils (nothing
moves) and ask someone with access to a calibrated Q meter ...university,
friend in manufacturing or lab, etc in Italy and ask them to measure the
coils and give you the results.

73 Kees K5BCQ

--------- Forwarded message ----------
From: "Luca Rossi" <[email protected]>
To: <[email protected]>
Date: Sat, 13 Mar 2004 21:03:37 +0100
Subject: [Boatanchors] HeathKit QM-1 calibration question
Message-ID: <003401c40936$86044fd0$5c8a0a3e@homexp2400>

Hi to all,
I am a, potentially happy, new owner of an Heath Q-meter mod.QM1.

Looking at the manual (another gift of BAMA) I have seen that I need a
reference inductor to do a correct calibration.

So, after years of desuetude and now a circuit refurbishment, I will need
something like that.

I am looking for someone that has or has had a QM1 or knows well how it
works.

#1 approximatively, what is the inductance value, wire section and
support
diameter of an original test coil?
#2 how can I reproduce a test coil of known Q and distribuited capacity
with
the only aid of a signal generator, a rcl meter and an oscilloscope?

Best regards from Italy,
** Luca Rossi **
[email protected]
http://www.geocities.com/chopin.i/

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