From: John Woodgate
Newsgroups: sci.electronics.design,rec.radio.amateur
Subject: Re: Improving a Grid Dip Meter
Date: Tue, 31 Dec 2002 08:25:06 +0000
Organization: JMWA Electronics Consultancy
Distribution: World
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Reply-To: John Woodgate
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I read in sci.electronics.design that carltons
wrote (in ) about 'Improving a Grid Dip Meter', on Tue, 31 Dec 2002:
>In article , John Woodgate
> wrote:
>
>> I read in sci.electronics.design that carltons
>> wrote (in > om>) about 'Improving a Grid Dip Meter', on Sun, 29 Dec 2002:
>> >The idea is sound, but I believe the
>> >implementation to be faulty in that the circuit be measured would pull the
>> >test instrument off freq. rendering the reading off by the length of the
>> >pull.
>>
>> No, with *loose* coupling and the GDO tuned for minimum grid current,
>> there is no pulling. The circuits are synchronous.
>
>
>Very loose I would imagine and probably not a dramatic effect to note.
>
No, it doesn't have to be *very* loose, just below critical coupling, so
that there is only on grid-current minimum.
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
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