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Re: Re: Drake Conversions to 432 MHz



Hi all,

Regarding the use of a Drake on 432 mhz IF with only a crystal change,
I note that the IF passband on the Drake is spec'd from 222 to 408 mhz.
Use on 432 would be a fair distance outside the passband, and therefore
not perform well.  At least not as well as if an IF passband modification
is made, or the an IF is chosen compatible with the existing Drake spec.

Now, to counter this, I decided to move my Drake to a 300mhz IF (crystal
changed to 8203.125 khz), and I am having worse luck in hearing AO-40
than the folks who did the quick mod by snipping out the IF filtering.

Go figure...

Greg.

p.s.  For those following my saga, measurements taken on the bench over
the weekend strongly suggest that my receive problem is mainly due to the
weak performance of the Confier preamp.  The Icom R7000 I am using for
an IF receiver is confirmed to be fairly deaf, but it's sensitive enough
to have the overall system noise limited at the converter.  I just need
to crank up the volume excessively and don't expect to see the S meter
move.

The Confier preamp seems to be performing close to spec.  Noise figure
and gain are, unfortunately, not up to the task.  Its gain seemed to
be a little under 10db, and with a small grill/dish and dipole feed,
there just isn't enough signal going into the Drake.

What was that $85 kit from DEM?  Can it be purchased not at Dayton?
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