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From: Mike <mikeberg@...>
Subject: [QRPLabs] Re: Hans Summer's web page 30m transmitter
To: QRPLabs@...
Date: Wednesday, June 23, 2010, 11:06 AM















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Thanks Hans,

I figured I might experiment with that design until
you're able to start shipping kits.



73 Mike N0QBH



--- In QRPLabs@...,
"hanssummers2000" <hans.summers@...> wrote:

Hi Mike

Can anyone tell me the values of the voltage

divider resistors biasing LED varicap in the schematic on
this page?

I think the upper resistor is 33k but have no

clue what the grounded one is.

Even I can't tell you that, sorry :-( Looks like

I shrunk that diagram too much. The good news is that the
values are entirely non critical. You could try with 33k in
both positions to start with. I believe I chose the values
in haste. It was merely to achieve, together with the 100K
resistor to the 4-bit digital-to-analogue converter, the
right amount of shift that I wanted. No magic to it. I think
it's just a matter of playing with the values until you
get the shift amount you want, subject to the component
tolerances and LED characteristics you have in your
circuit.

73 Hans G0UPL