[amsat-bb] SatPC32 Doppler Correction/Calibration?

David Rush david at rushtone.com
Thu Jun 22 22:34:11 UTC 2017 

I just gave this a shot at an XW-2C pass this evening here in EM72.

I reset the uplink and downlink in Doppler.SQF to 145805.0 and 435160.0 
(center of the passband).

Once the bird popped far enough off the horizon to hear its beacon, I 
tuned back to a clear spot on the pass band.

I opened the CAT menu, and intermittently poked the uplink correction 
buttons and transmitted, until I found myself.  I saved the uplink 
correction.

Closed the CAT menu but was never able to find myself again.  I had a 
few minutes before LOS, and tweaked the D/L correction a bit on either 
side, but nothing before LOS.

Looking at Dopper.SQF, it now shows 145805.0 and 435159.53.  So the save 
worked, but still can't hear myself right where I should be, nor find 
myself tweaking the D/L correction before LOS.

Bah.

David, ky7dr

On /20170622/ 08:02, David Rush wrote:
> George:
>
> Okay, I'll give that a shot this evening.  Thanks.
>
> David, ky7dr
>
>
> On /20170622/ 00:10, George Henry wrote:
>> Go into your Doppler.sqf file and edit the up- and downlink 
>> frequencies back to the original values.  Then use the uplink 
>> calibration buttons to find yourself on the downlink.  Then click the 
>> Change/Store data file button and store the uplink calibration.  I've 
>> never touched the downlink correction on a sat with a linear 
>> transponder...
>>
>> George, KA3HSW
>>
>>
>> ----- Original Message ----- From: "David Rush" <david at rushtone.com>
>> To: <amsat-bb at amsat.org>
>> Sent: Wednesday, June 21, 2017 7:53 PM
>> Subject: Re: [amsat-bb] SatPC32 Doppler Correction/Calibration?
>>
>>
>>> Okay, I followed the instructions (as I described below).  I found 
>>> myself on a couple of the XW-2* birds, and kept adjusting my 
>>> downlink correction until I was at about peak elevation in the pass 
>>> (I even made one contact while one of the birds was still on its way 
>>> up).  Then zeroed out the downlink correction and entered the 
>>> opposite in uplink correction, and saved it.
>>>
>>> Once I did that I did not hear myself on the downlink, and failed to 
>>> find myself, even trying a few 10s of hz of d/l correction either 
>>> side, before the birds got too low on the horizon.
>>>
>>> What am I doing wrong?
>>>
>>> David, ky7dr
>>>
>>>
>>> On /20170621/ 07:44, David Rush wrote:
>>>> George:
>>>>
>>>> Thanks for the reply.  So by repeatedly trying the same thing, have 
>>>> I shifted the uplink frequency by a bit more every time? Sounds 
>>>> like I may need to set those back.  Or else just find a new value 
>>>> in the opposite direction (starting a few multiples of the 160), 
>>>> set it once, and leave it.
>>>>
>>>> 73, David, KY7DR
>>>>
>>>>
>>>> On /20170621/ 00:55, George Henry wrote:
>>>>> You're doing it right...  once you store the uplink calibration, 
>>>>> the calibration values WILL return to zero, but if you look at the 
>>>>> uplink frequency displayed in the right-hand panel of the CAT 
>>>>> window, it will have a new value which is offset from the original 
>>>>> frequency by whatever calibration value you stored.
>>>>>
>>>>> 73,
>>>>> George, KA3HSW
>>>>>
>>>>>
>>>>> ----- Original Message ----- From: "David Rush" <david at rushtone.com>
>>>>> To: "Amsat BB" <amsat-bb at amsat.org>
>>>>> Sent: Tuesday, June 20, 2017 7:59 PM
>>>>> Subject: [amsat-bb] SatPC32 Doppler Correction/Calibration?
>>>>>
>>>>>
>>>>>> I'm trying to get the doppler correction/calibration set up for 
>>>>>> the various birds before Field Day, but I'm just not making any 
>>>>>> tangible progress.
>>>>>>
>>>>>> I've got a pair of Yaesu FT-817ND rigs, and can successfully tune 
>>>>>> both of them with SatPC32's CAT controls.
>>>>>>
>>>>>> Following the directions for a two-rig calibration process, I've 
>>>>>> been catching the XW-2* birds and can occasionally get the 
>>>>>> downlink correction set to where I can hear myself on the downlink.
>>>>>>
>>>>>> In a couple of cases I've made note of where that downlink 
>>>>>> calibration was near mid-pass (the necessary correction changed 
>>>>>> constantly across the pass).
>>>>>>
>>>>>> Then I go into the CAT menu, set the downlink correction to zero 
>>>>>> and the uplink calibration to the opposite sign of the previously 
>>>>>> found downlink correction at mid-pass.
>>>>>>
>>>>>> For example on a recent pass of XW-2C I found a downlink 
>>>>>> correction of -160 Hz was working well near mid-pass (I could 
>>>>>> hear myself) so I set the uplink calibration to 160 Hz.
>>>>>>
>>>>>> The "Upl. Calibr." window in the CAT pop-up says "160", and the 
>>>>>> grey box above the uplink frequency in the main window also says 
>>>>>> "160".
>>>>>>
>>>>>> I click on the "Change/Store Dataf File" button, then click on 
>>>>>> the "Store" "Uplink Calibration" button on the next pop-up.
>>>>>>
>>>>>> It says "The changings have been stored!" but the uplink 
>>>>>> calibration in both the first popup and the main window are back 
>>>>>> to zero.
>>>>>>
>>>>>> I click the X to close both pop-ups, and uplink correction in the 
>>>>>> main window is still 0.  I exit the program, restart it, select 
>>>>>> XW-2C, enable CAT (C+) and the uplink calibration is still on zero.
>>>>>>
>>>>>> What am I missing?
>>>>>>
>>>>>> David, ky7dr
>>>>>>
>>>>>> _______________________________________________
>>>>>> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum 
>>>>>> available
>>>>>> to all interested persons worldwide without requiring membership. 
>>>>>> Opinions expressed
>>>>>> are solely those of the author, and do not reflect the official 
>>>>>> views of AMSAT-NA.
>>>>>> Not an AMSAT-NA member? Join now to support the amateur satellite 
>>>>>> program!
>>>>>> Subscription settings: 
>>>>>> http://www.amsat.org/mailman/listinfo/amsat-bb
>>>>>
>>>>>
>>>>> ---
>>>>> This email has been checked for viruses by Avast antivirus software.
>>>>> https://www.avast.com/antivirus
>>>>>
>>>>
>>>> _______________________________________________
>>>> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
>>>> to all interested persons worldwide without requiring membership. 
>>>> Opinions expressed
>>>> are solely those of the author, and do not reflect the official 
>>>> views of AMSAT-NA.
>>>> Not an AMSAT-NA member? Join now to support the amateur satellite 
>>>> program!
>>>> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
>>>
>>> _______________________________________________
>>> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
>>> to all interested persons worldwide without requiring membership. 
>>> Opinions expressed
>>> are solely those of the author, and do not reflect the official 
>>> views of AMSAT-NA.
>>> Not an AMSAT-NA member? Join now to support the amateur satellite 
>>> program!
>>> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb 
>>
>
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. 
> Opinions expressed
> are solely those of the author, and do not reflect the official views 
> of AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite 
> program!
> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

More information about the AMSAT-BB mailing list