Message-Id: <7.0.1.0.1.20100903145931.0185e860@magma.ca>
Date: Fri, 03 Sep 2010 15:06:40 -0400
To: rsgb_lf_group@blacksheep.org
From: Bill de Carle <ve2iq@magma.ca>
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Subject: LF: Re: VE7TIL TX Loop tests continue.............
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At 09:58 AM 9/3/2010, I wrote:
>[..]
>One idea I am kicking around is to pass the 50-ohm signal at the 
>antenna connector through the centre of a toroid with a lot of turns 
>on the secondary - enough that we see millivolts instead of 
>microvolts.  Then I would do the clipping on the hi-Z side using a 
>couple of fast op-amps with a variable threshold setting, hoping the 
>hi-Z clipping gets reflected back thru the toroid to the 50 ohm 
>side.  Not good for HF but at 137 Khz it might work well enough.

Oops..  think it'd take 3 windings on the transformer: 50 ohms in, 50 
ohms out, plus a third winding to shunt excess energy to ground so it 
doesn't couple into the receiver.  I reserve the right to make more 
mistakes :-)

Bill VE2IQ