Re: [amsat-bb] Fw: HF-HF satellite (OSCAR LOCATOR?)
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude of the inclination of the orbit. And I understand the circular plot which is angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the orbital period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR
Hi Bob, Rather than vertical, I see a very steep orbit, near to 90deg. It resembles a straight line, but it is a curved one indeed, with time increment calibration after EQX. I hope my explanation be useful. Best 73. EA4DUT, Angel
Enviado desde mi iPhone
El 27/5/2016, a las 16:09, Robert Bruninga bruninga@usna.edu escribió:
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude of the inclination of the orbit. And I understand the circular plot which is angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the orbital period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@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
Oh I remember that well -- thanks for bringing that memory back! And I know I have mine in a box somewhere.
PDF files of one version are here: http://www.qsl.net/pe1rah/oscarlator.htm
I seem to recall using the locator to establish a baseline orbit off of ephemeris data that was received via ARRL CW bulletins (I think I remember that correctly), then using that baseline to feed into a HP 9830 desktop calculator which ran interpolation routines to give me a week's worth of rise data. The local HP rep loaned me that calculator (I was in middle school at the time). My parents had no idea that HP was worth about half the price of their home back in 1972 (nor did I).
73, Bob, WB4SON
On Fri, May 27, 2016 at 10:38 AM, Ángel Peláez Martínez amsat-bb@amsat.org wrote:
Hi Bob, Rather than vertical, I see a very steep orbit, near to 90deg. It resembles a straight line, but it is a curved one indeed, with time increment calibration after EQX. I hope my explanation be useful. Best 73. EA4DUT, Angel
Enviado desde mi iPhone
El 27/5/2016, a las 16:09, Robert Bruninga bruninga@usna.edu escribió:
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude
of
the inclination of the orbit. And I understand the circular plot which
is
angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the
orbital
period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@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@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
Bob,
You might be interesting in this computerized version:
http://www.tomdoyle.org/OscarLocator/OscarLocator.html
Neat, and kind of reminds me of the mythical microprocessor driven slide rule we joked about in graduate school. ca 1975.
73s,
Alan WA4SCA
<-----Original Message----- <From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Robert Bruninga <Sent: Friday, May 27, 2016 9:10 AM <To: amsat bb amsat-bb@amsat.org <Subject: Re: [amsat-bb] Fw: HF-HF satellite (OSCAR LOCATOR?) < <> Sat tracking in the early days was with an AMSAT <> OSCAR-LOCATOR (Rotating mylar discs over a global map!!). < <I just googled and there is only one image of an OSCARLOCATOR I can find. <I remember it well, but am confused by this image: <http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg < <I understand the curved trace. It crosses near the pole at the latitude of <the inclination of the orbit. And I understand the circular plot which is <angle and elevation from your QTH when placed over your house. But I do <not understand the straight line scale going nearly vertical and labeled <RS? WHy is there no curve to it? < <And the only other one I found was this: <http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg < <Which looks like it has the orbits of three different satellites, one of <them added on in green marker. But this one is lacking the AZ/EL circle <for the station. < <Is there a better image anywhere that I can use to justify this "minimum <satcom" experiment? < <And is this how it worked? You got the daily zero crossing of the <equator. Then for the next 24 hours you could just rotate the plastic <overlay by the longitude increment? ANd increment the time by the orbital <period? < <On a trip and without a smart phone, I'd rather do an OSCAR locator then <fuss with a PC... < <Bob, WB4APR <_______________________________________________ <Sent via AMSAT-BB@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
Hi Bob, The OSCARLOCATOR I have has a page w/overlays for AO-7 and AO-8. The whole document is a tri-fold with explicit instructions and a history table of OSCAR 1 through Phase IIIA. I'll color copy it and mail it to you. (It's from 1981.) Somewhere, I have the Polar Projection Globe Sheets with the mylar overlays for various RS Birds that came from an early Satellite Handbook. When I go on a trip, I go to the AMSAT Pass Predictor and enter the Grids that I plan to be in and copy the data for the Sat's I plan to use. And, when I get to the location, I find North and set up my Arrow on my Camera Tripod and start working stations AOS-LOS according to the data. Works great for me and no computer needed in the field. 73, Bob K8BL
From: Robert Bruninga bruninga@usna.edu To: amsat bb amsat-bb@amsat.org Sent: Friday, May 27, 2016 10:09 AM Subject: Re: [amsat-bb] Fw: HF-HF satellite (OSCAR LOCATOR?)
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude of the inclination of the orbit. And I understand the circular plot which is angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the orbital period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@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
Bob
Search for the November 1977, 73 Magazine. It is available online. The whole issue was dedicated to things Oscar in prep for Oscar 8
I have an AMSAT owned copy of an Oscar Locator, I would gladly loan you if you are interested.
73 EMike
EMike McCardel, AA8EM Rotating Editor AMSAT News Service Sent from my iPhone
On May 27, 2016, at 10:09 AM, Robert Bruninga bruninga@usna.edu wrote:
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude of the inclination of the orbit. And I understand the circular plot which is angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the orbital period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@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
Bob
There is also a good description of the Oscarlocator in Martin Davidoff's K2UBC book The Satellite Experimentor's Handbook. Copyright 1990.
EMike McCardel, AA8EM Rotating Editor AMSAT News Service Sent from my iPhone
On May 27, 2016, at 10:09 AM, Robert Bruninga bruninga@usna.edu wrote:
Sat tracking in the early days was with an AMSAT OSCAR-LOCATOR (Rotating mylar discs over a global map!!).
I just googled and there is only one image of an OSCARLOCATOR I can find. I remember it well, but am confused by this image: http://www.amsat.org/amsat-new/tools/images/oscarlocator.jpg
I understand the curved trace. It crosses near the pole at the latitude of the inclination of the orbit. And I understand the circular plot which is angle and elevation from your QTH when placed over your house. But I do not understand the straight line scale going nearly vertical and labeled RS? WHy is there no curve to it?
And the only other one I found was this: http://www.studiorite.com/oldindex/images/OscarLocator1sm.jpg
Which looks like it has the orbits of three different satellites, one of them added on in green marker. But this one is lacking the AZ/EL circle for the station.
Is there a better image anywhere that I can use to justify this "minimum satcom" experiment?
And is this how it worked? You got the daily zero crossing of the equator. Then for the next 24 hours you could just rotate the plastic overlay by the longitude increment? ANd increment the time by the orbital period?
On a trip and without a smart phone, I'd rather do an OSCAR locator then fuss with a PC...
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@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
On the FO29 west pass today I had the privilege of being Allen's (N5AFV) 57,000th contact! Well done, My Good friend!!! And Hector (W5CBF) was his 57,001th! 73 George WA5KBH
participants (7)
-
Alan -
Bob -
E.Mike McCardel -
gkcarr＠go-express.net -
R.T.Liddy -
Robert Bruninga -
Ángel Peláez Martínez