Topics

We're off and running!

Mark <Mark@...>
 

Hi All

I've completed the VFO today, some pictures on the reflector.

Just need to wait for Hans Components Inc before we go any further.

VFO swinging from 4.25MHz to 4.4MHz - very adjustable with the
trimmer.

I used a fixed inductor of 22uH instead of the tap washer and 150
turns of 32swg - can't count that high.

What are other people planning for inductor cores - is the general
plan to proceed with tap washers or has anyone done the calcs for
more conventional cores?

Your comments welcome.

Mark G0MGX

Hans Summers <Hans.Summers@...>
 

Now the heat's really on at Hans Compoments Inc, then ;-)

I used the tap washers for the inductors. Mine are a black rubbery type of
material, I didn't find white nylon ones like Farhan's photos. It was fun to
do things a bit "differently". I was not finding it so fun in the middle of
150 turns on the VFO coil but proud of the result when I'd finished.

http://www.gqrp.com the GQRP club sell the FT37-43 toroidal cores which I
used as per Farhan's recommendation in place of TV baluns. Club sales are
for members only, £0.75 per pack of 5 and they sell all the normal types
too. There are calculators and toroid inductance charts all over the
internet, a google search will find one immediately. I wonder if temperature
stability will be better in the case of the tap washers than a ferrite core?

72/3 de Hans G0UPL
http://www.hanssummers.com

-----Original Message-----
From: Mark <Mark@...>
To: BITX20@... <BITX20@...>
Sent: Sun Jun 20 13:19:36 2004
Subject: [BITX20] We're off and running!

Hi All

I've completed the VFO today, some pictures on the reflector.

Just need to wait for Hans Components Inc before we go any further.

VFO swinging from 4.25MHz to 4.4MHz - very adjustable with the
trimmer.

I used a fixed inductor of 22uH instead of the tap washer and 150
turns of 32swg - can't count that high.

What are other people planning for inductor cores - is the general
plan to proceed with tap washers or has anyone done the calcs for
more conventional cores?

Your comments welcome.

Mark G0MGX





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