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From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <201101111216460781.5C69093B@smtp2.numeo.fr>
Date: Tue, 11 Jan 2011 11:38:52 -0000
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Subject: LF: Re: RF ammeter question
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Hi John most probably......... the 1N4148 is a fast switching diode whereas
the 4007 is intended to rectify at about 1amp, so has a bigger area junction
and a lot more capacitance, and probably a longer carrier lifetime.
Alan G3NYK

----- Original Message ----- 
From: "John RABSON" <john.rabson@numeo.fr>
To: <rsgb_lf_group@blacksheep.org>
Sent: Tuesday, January 11, 2011 11:16 AM
Subject: LF: RF ammeter question


LF,

I have built the fullwave rectified version of the design shown on page
10.33 of the RSGB Handbook 10th edition.  It reads correctly at 25kHz but
only show 1/3 of the correct value at 136.

Not having any 1N4148 diodes I used 1N4007s.  Might this be the cause of the
problem?

73
John F5VLF