Markus,
Thank-you for mentioning this problem. If it's QRO -> DDS it's
likely due to shoddy construction technique by the operator!
When this has been dealt with, we can try some OP32.
73
Joe
On Fri, 7 Jun 2013, Markus Vester wrote:
Hi Joe,
looks like carrier stability was good while the signal was weak, but
deteriorated after 2 UT. DDS affected by QRO?
Best 73,
Markus (DF6NM)
From: [email protected]
Sent: Thursday, June 06, 2013 1:34 AM
To: [email protected]
Subject: Re: LF: 137.7770 kHz
Hi Stefan, Markus and Jean Pierre F1AFJ (Grabber service),
Thanks for the report, Stefan. I am happy you have something nice to
say about my sigs. Its good that they are reaching you when we are so
close to the solstice.
They were also quite strong around that time on Jean Pierre's grabber as
well.
As for Markus, he provided what I asked for -- and now I must say his
very critical report is most gratefully received. :-) The problem seems to
have disappeared after the 10 MHz input to the AD9851 was boosted with
a BJT amp. The original interface simply offset the 1.5 V p/p
to 2.5V DC; the new one bosted it to 0-3V which is more in line with
the specs for the DDS. Perhaps the chirps and phase glitches were
due to RF interfering with the weak 10 MHz input.
I will be happy to try OP32 on another frequency soon.
Thank-you very much for the good news and thanks all around.
The TX is now again QRV on QRSS30. (2330 UTC)
73
Joe
This electronic communication is governed by the terms and conditions at
http://www.mun.ca/cc/policies/electronic_communications_disclaimer_2012.php
|
