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R: Vo-52 Daft Question



Hi Simon and entire list...

I'm happy to see your question posted here... this should mean that we
should get some improvements to the Sat part of Ham Radio Deluxe soon
enough! :-)

About your question... I'm also a total novice in this fascinating field and
I'm not sure about what you notice on VO-52 pass...

Anyway, I would guess that is the result of wrong use of doppler correction
functions in Control programs, or poor implementation of those functions...

At my first attempts on VO-52, I was trying hard to use the Automatic
Doppler corrections' tecniques in HRD with my TS-2000, but I always ended-up
hearing myself high-pitched like Donald Duck or low-pitched like an ogre
(Shrek?) :-)

This went on a couple of days 'til a very experienced Italian Sat operator
suggested me to forget about the Auto Doppler correction and use the manual
adjust of the uplink (Higher of the two frequencies...) technique while
listening always on the same frequency... he told me to act like my RTX had
no more RX Tuning Knob... :-)

Please note that he's not an "Old Farth" scared of computer things... he's a
VERY technically minded operator but, nevertheless he prefers those manual
techniques...

Well, using that manual technique, even if it was hard at first, I finally
managed to complete some contacts on the great VO-52! My biggest drawback is
that I'm using a simple dual band high gain collinear vertical for both Up &
down, so I often lose my DL signal and then is difficult to keep the UL
tuned... in this situation (or when in the chat the other party does a
rather long passage, allowing the Doppler shift to become substantial),
complete PC control OF TX ONLY would help for sure...

But I don't know why, as soon as I try to transfer control to the PC, I
start sounding like Donald Duck or Shrek... and so my pitch remains as long
as the control is at the PC... (Keps are updated regularly, so these should
be OK...)

Beside my fellow Italian Ham's advice, I've found very useful this reading:

http://www.amsat.org/amsat/features/one_true_rule.html 

..I'm sure most of you already know this stuff, but it is a very interesting
reading for novices like myself...

Sorry for long (...and maybe pointless...) post... as I said, I've got a
tons of things to learn still...

Thank you all for sharing your knowledge...

Thanks Simon (and the great, unforgotten Pete...) for HRD! ;-)

73 de Joe, IW7ECJ





> -----Messaggio originale-----
> di Simon Brown (HB9DRV)
> Inviato: lunedì 27 giugno 2005 14.40
> Oggetto: [amsat-bb] Vo-52 Daft Question
> 
> While listening to a recent VO-52 pass it became clear to me that many
> users were not compensating for Doppler effect. Surely the preferred way
> of using VO-52 and similar is to apply frequency correction?
> 
> Simon Brown
----
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