[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

R: SAT Mode on IC-910H / FT-847



Hi Simon...

You already have a reply to this question, but I'll add my comments that are
related to a TS-2000 (SAT capable like the 910 / 847...)

> I don't own a radio with SAT mode, please help me here.
> 
> I set the RX VFO to 145.900, the TX VFO to 435.350 and press the SAT
> button.

OK... here the TS-2000 is similar to the 910H, and I believe to the 847:
Pressing "SAT" Button gives you access to a specialized MEMORY mode... I
would say a "Half memory-Half VFO Mode" since HRD is still able to read the
frequencies of my TS-2000...

> 
> [1] What happens if I change the RX freq to 145.910 - what is the new TX
> frequency?

If the RTX is set for "Normal Trace", TX changes to 435.360
IF the RTX is set for "Reverse Trace" TX changes to 435.340

The former Trace mode is for Non-Inverting Transponders, the latter is for
Inverting Transponders (VO-52)

> [2] What happens if I change the TX freq to 435.340 - what is the new RX
> frequency?

Normally, if you change the TX frequency, the RX follows the same behavior
detailed above but...

The TS-2000 has a particular set-up that allows the TX frequency to be
changed WITHOUT affecting the RX... even if in one of the Trace modes...

This is handy when you follow the rule of changing ONLY your TX frequency
(well... actually the highest of the two frequencies, because is more
subject to Mr.Doppler...) to compensate for Doppler shift, leaving the RX
absolutely FIXED! Without this option, each time you need to correct for
Doppler, you HAVE to disengage the Trace function, and re-engage it when you
need to QSY around in the passband of the SAT transponder searching for
contacts or for a clear frequency

> To correctly compensate for Doppler on VO-52 I assume that I must update
> *both* VFO's even when the radio is in SAT mode.

This, I believe, is covered in the link I posted before... when using full
PC control of the rig for Doppler correction, both RX & TX should be read
and updated... this is to maintain the same frequency AT THE SATELLITE! Of
course, this mean that signals will be travelling in the passband when seen
from Earth...

The trouble starts, I believe, because not all people are using full PC
control, nor are they ALL using manual Doppler correction techniques :-)

> Exactly what does SAT mode do - in simple terms please :)

On my TS-2000, the SAT button puts the rig in that special Memory mode and
allows full duplex operation of the transceiver while making available
"Trace Mode" to allow easy QSY in the SAT passband... once you have
correctly set your TX to allow for clear reception on the DL, I mean...

> Myself I am looking at controlling two radios, probably TX with the FT-817
> and RX with IC-7800 + transverter.

Nice set-up you are going to assemble, Simon...

About your question on transverters in another post...

You may try http://www.ssb-amateur.de/amateur/index_e.html , but prices are
high anyway or, if you settle for a downconverter instead of a transverte,
please check this website:
http://www.keps.it/ 

Ciao Simon... hope to hear you calling on VO-52 one of these nights...

73 de Joe, IW7ECJ
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home