PAUL,
The Demi Micro-Lo is notorious for drift which of course they have a Syn
board you can replace that requires 10mhz to lock it. You can buy an 10mhz
OCXO for $10 on the internet that will work fine to lock it.
Take a look at this site https://zl2bkc.com/ which also has a replacement
board for the Micro-Lo.
73
Steve
--------------------------------------------------
From: "N1BUG" <paul@n1bug.com>
Sent: Wednesday, April 25, 2018 3:20 AM
To: "VHF Contesting" <vhfcontesting@contesting.com>
Subject: Re: [VHFcontesting] What separates a decent transverter from an
awesome transverter?
One thing I didn't see on your list that always concerns me is LO
drift. Drift can be a problem for any weak signal work, say a long
haul CW sked during a contest. If you want to do some of the digital
modes it can become a critical issue, even a show stopper.
Since I can neither afford nor get my head around the complexities
of GPSDO locking, I am always concerned about crystal oscillator
drift in transverters. Usually I do the best I can to build and
install some type of crystal heater... with mixed results over the
years.
Sometimes I find things that surprise me. Last summer I measured
drift on two 1296 transverters: a relatively ancient UHF Units and a
relatively newer but not current generation DEMI, both as yet
unmodified. Over a temperature range that caused the DEMI to drift
over 6 kHz, the UHF Units moved just a bit over 200 Hz! I know which
one I will be using if I ever get the rest of the stuff together for
1296.
Paul N1BUG
On 04/24/2018 10:31 PM, Patrick Thomas wrote:
Hey all,
Subject more or less says it all... I guess better sensitivity,
lower noise, better selectivity, and better linearity are the
essentials in vague and relative terms, but what attributes do
you look for in a REALLY GOOD transverter?
Or for those who have gone further into making them... what
components, construction techniques, etc., make a difference?
Partly this is a question I hear a lot and only have a vague
notion of how to answer other than "obviously the expensive ones
are better... somehow." :)
And partly it is a request for topics for self-guided
study/experimentation as I attempt my own homebrew projects.
Many thanks,
Patrick - KB8DGC
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