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SV8VS LF: Bad news / help request

To: <[email protected]>
Subject: SV8VS LF: Bad news / help request
From: "SV8CS-Spiros Chimarios" <[email protected]>
Date: Mon, 31 Dec 2018 14:26:31 -0000
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Hi, Paul-N1BUG.
First of all I agree with you to use all of this modes (JT9, JT9-2, T9-5, QRSS, FT8 etc) to making qsos and not only 'Beacon". I am using also the FT-2000 and I have exactly the same problem (not have any decode of my signal in JT9-5).
JT9, JT9-2, WSPR-2, WSPR-15 going well without problems.
Later today I will test with another transceivers (IC-756, TS-2000 - FT-847) to see if the problem has the solution.
I will let you know.
73 HNY and I hope for a LF and MF qso with you in the 2019.
Spiros/SV8CS



-----Original Message----- From: N1BUG
Sent: Monday, December 31, 2018 13:59
To: [email protected] ; [email protected] ; Discussion of the Lowfer (US, European, & UK) and MedFer bands ; [email protected]
Subject: LF: Bad news / help request

So, the latest SlowJT9 test is completed. I regret I was not able to
run one night on 630m as planned.

I used a QRP Labs Ultimate 3S beacon transmitter for these tests.
Yesterday I checked my ability to use JT9-5 for QSOs and found that
I have none! My FT-2000 transceiver has too much drift to be of any
use on JT9-5 and is very marginal even for JT9-2. What a huge
disappointment, though it did not come as any surprise.

I can think of several ways to solve this but am not sure any of
them can save some part of this winter season:

1. Add insulation and a heater to the FT-2000 TCXO area. I will try
this but I am not convinced I can make enough improvement. The drift
is really ugly!

2. Replace the FT-2000 TCXO with an outboard programmable GPS
referenced oscillator, for example a Leo Bodnar unit. The trouble
with this is I do not have sufficient knowledge or experience to
know what kind of problems might be encountered. The GPSDO is enough
of an investment to kill any and all other attempts at a resolution
if I am unable to make it work.

3. Use a divide-by-100 circuit with the FT-2000 operating at 13.6
MHz instead of a LO/mixer converter from 10 MHz. This should reduce
drift to the order of 0.1 Hz, probably quite acceptable. So far I
have not found a divide-by-100 circuit using a modern/available part.

4. Run away from the junk FT-2000 completely, using audio to 136 kHz
converter for Tx and 136 kHz to audio converter for Rx. This is
finally the direction I want to go but there seems to be much
learning left to do and a lot of building. It's probably not a
solution which can be completed in time for this winter season.

If anyone has experience in any of these areas and is willing to
share knowledge, please get in touch with me. This may be the last
solar minimum for me, and I would like to make some LF/MF DX QSOs
before these incredible conditions fade away.

73,
Paul N1BUG

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