New to Satellite monitoring.

[steve2004]

Been scanning VHF/UHF with conventional scanner.

I have a 10' C-band to play with.
(do I need a special LNB)
what do I do? just connect a scanner to it and point it up?
my scanner goes up to 1.3G


Thanks.

 

[Caesar]

i am not going to be able to help much, b/c i haven't messed with the sat scanning myself, but each lnb is built for a specefic freq, so it probably will matter, if your scanner only goes to 1.3ghz and you get a 3.2ghz lnb..well, same effect as having an antenna, but c-band is usually lower freq than the ku-band and others though i believe anyway...

 

[mancow]

I envy you. I wish I had one.

What I would do....

Go Google helical antenna feeds adn start reading. From what I've gathered so far you can wind a fairly simple 3 to 5 turn anti-clockwise left hand polarized helix above a reflector and put that in the focal point. With a preamp you should be able to get all kinds of stuff.

I just about finished my 20 turn helical 1.5 Ghz antenna but I can't get away from work long enough to finish it totally and test it.

 

[grem467]

it would be very difficult to plug in your scanner to that LNB and make it work, typically they are powered by DC on the coax, plus they downconvert the microwave frequency to something more managable for a long run of coax.

 

[mancow]

Yep, that's why you throw out the existing LNB and put the left hand helix in there. I have found a few neat downconverters on ebay lately for the 2.4 ghz range.

I'm looking for a 1.5 to Vhf or Uhf but haven't found one of those yet.


With all of that real estate he has in that antenna he should be able to put it to good use somehow.

 

[grem467]

which way would you point the helix?

keep in mind the dish is merely a reflector that bounces the signal back up into the lnb, i suppose you could aim the helix at the reflector, but you would need to do the math to find the focal point and take into account the extra gain of the helix itself.

Aiming it up away from the dish would not take advantage of the refection, and could possibly make reception more difficult if the reflected signal and the signal direct into helix are out of phase with one another.

 

[jlh]

point the helix at the focal point of the reflector. start off with it in the same are where the original lnb was, and move it slightly until strongest signal is heard. then brace it.

mancow, if you're looking for a dish, drive around and look for yards with both big dishes and little dishes. offer to disassemble and remove the big dish for free. most people who have switched to directv, dish network, etc would love to get rid of the eyesore.

 

[steve2004]

point the helix at the focal point of the reflector. start off with it in the same are where the original lnb was, and move it slightly until strongest signal is heard. then brace it.

mancow, if you're looking for a dish, drive around and look for yards with both big dishes and little dishes. offer to disassemble and remove the big dish for free. most people who have switched to directv, dish network, etc would love to get rid of the eyesore.

In Canada C-band is almost dead... so that's what I do also...
I wish I could find a 12' to 16' by driving around....
I could put at leat 5 working 10' Dish if (the wife would let me to...)

So it's time to bring scanning to a new Level.


btw: will the "AOR AR ONE" Super wide coverage: 10 KHz ~ 3.3 GHz
do the Job for satellite scanning?
what is the frequency range for sattelite scanning anyway?

 

[jlh]

...btw: will the "AOR AR ONE" Super wide coverage: 10 KHz ~ 3.3 GHz
do the Job for satellite scanning?
what is the frequency range for sattelite scanning anyway?...

the range for inmarsat is 1.5 - 1.6 gigahertz. never used an AOR AR ONE. i used a yupi 7100. i did compare the yupi 7100 against an AOR 8200 on inmarsat, the yupi performed much better.

 

[SCPD]

Might try this trick

Steve, Here is a trick I use to do back several years ago to find hinden signals in the regular C Band service. If you have a C Band receiver that has a raw video output connector and a shortwave receiver unit you can connect the raw video output to the antenna connector on the shortwave receiver. Then tune from about 500 Khz to approx. 10 Mhz and you will be amazed at what you might find. Try both USB and LSB and AM modes. And of course try this at your own risk!

 

[mancow]

which way would you point the helix?

keep in mind the dish is merely a reflector that bounces the signal back up into the lnb, i suppose you could aim the helix at the reflector, but you would need to do the math to find the focal point and take into account the extra gain of the helix itself.

Aiming it up away from the dish would not take advantage of the refection, and could possibly make reception more difficult if the reflected signal and the signal direct into helix are out of phase with one another.

You point it to the dish as stated with an opposite twist due to the inversion of the polarity from the reflection off the dish.

 

[mancow]

the range for inmarsat is 1.5 - 1.6 gigahertz. never used an AOR AR ONE. i used a yupi 7100. i did compare the yupi 7100 against an AOR 8200 on inmarsat, the yupi performed much better.

I think I'm getting something in that range but it's noisy and they are dead carriers.

I'm using a 20 turn helical mounted to a Cellwave preamp made for the 1470 mhz range and that feeds an Icom R20.

Then again, I have only tried it with it mounted to the tripod looking out the window. According to a sat location calculator I found on line http://www.hollsco.com/Products/SatCalc/index.asp

The 2-F2 sat should be at:

Bearing: 185 degrees point to 185 degrees
Elevation: 44.9 degrees point 44.9 degrees


That puts it right out my South window and over the neighbors roof with no obstructions.

My helical has a small aluminum L beam as the main boom so I hope that is not causing it to lose gain. I have heard what sounds like faint data streams in the noise but nothing interesting yet.

A few Questions...

How strong are the carriers? I assume fairly weak due to the need for the preamp.
What should you expect to hear? Is the analog system basically dead (unused)?
Is the system all that busy at all?

 

[jlh]

mancow, you can use this to find AOR-W and AOR-E. i mostly used AOR-W. AOR-E was weaker from my location ( central NC, USA ). aiming is critical.

http://www.time-step.com/reviews/mt_inmar2.htm

the carriers were noticable, you will know when you hit one.

it's been 2 or 3 years since i did it, they were pretty active then, heard some very interesting stuff, have no idea about how busy it is now.

 

[mancow]

I took it outside tonight but I think my preamp is the main culprit right now. I got a few 800 mhz analog cell signals trying to come in and one conventional PD channel. I did pick up quite a few weak but readable data signals that didn't sound like anything I have ever heard before. They were rhythmic, alot like weather satellite sounds on Vhf but not quite the same.

I did hear what sounded exactly like 1.8 / 1.9 Ghz PCS signals (annoying buzzing). I'm not sure if it was something mixing from a nearby PCS tower or not. However, that signal did come in only when pointed in the proper direction of the satellite. I would assume the TDM they use would be the same type of format as terestrial systems and it would make sense that it would sound the same.

I never did hear anything else beyond the other few dead carriers with a slightly lower signal level. The aiming did seem critical and the signals came in exactly where that program told me to aim 40 x 185 degrees. I still don't know about the antenna and I guess I never will without a million in test equipment. I have an IFR1900 good to 2.1 Ghz but it won't help with an SWR test without add on equipment.

I also picked up some #14 solid wire and I found two 2" PVC tubes in the garage the right length already. I guess I will try again with that. Atleast it will be a ruggedized version this time that I don't have to baby.

The hi gain low noise preamp from mini-kits out of Austrailia was ordered two weeks ago but it still hasn't arrived. I'm anxious to see what that thing will do.

 

[jlh]

mancow, check PM

 

[steve2004]

Steve, Here is a trick I use to do back several years ago to find hinden signals in the regular C Band service. If you have a C Band receiver that has a raw video output connector and a shortwave receiver unit you can connect the raw video output to the antenna connector on the shortwave receiver. Then tune from about 500 Khz to approx. 10 Mhz and you will be amazed at what you might find. Try both USB and LSB and AM modes. And of course try this at your own risk!

Very Interesting!

Thanks.

 

[acarsnut]

Quote:
Originally Posted by GADSDENEDACS
Steve, Here is a trick I use to do back several years ago to find hinden signals in the regular C Band service. If you have a C Band receiver that has a raw video output connector and a shortwave receiver unit you can connect the raw video output to the antenna connector on the shortwave receiver. Then tune from about 500 Khz to approx. 10 Mhz and you will be amazed at what you might find. Try both USB and LSB and AM modes. And of course try this at your own risk!


Hey I used to do this to listen to ship to shore telephone comms.It worked out great.Also at one time you could contact red roof inns and they were giving away all there sat dishes.you had to fill out a paper sent to you by email.and tell them how far you would go to pick up.try there web site and see if there still doing this.Dont know what kind they were but free helps.I use my c band with a free to air receiver to get 4 channels of nasa.

 

[mancow]

point the helix at the focal point of the reflector. start off with it in the same are where the original lnb was, and move it slightly until strongest signal is heard. then brace it.

mancow, if you're looking for a dish, drive around and look for yards with both big dishes and little dishes. offer to disassemble and remove the big dish for free. most people who have switched to directv, dish network, etc would love to get rid of the eyesore.

My uncle has a nice 8' setup at his place but the wife would kill me if if I drug that thing home. I'm pushing it with an old primestar sitting on the ground out there now that I used before working out a deal on a fold up type.

BTW, if anyone is interested I can get some pics of the feed I made for the primestar. It seems to work great now that I have a good preamp. I used a small 12" x 6" or so sheet of copper from the hobby store. I made a 3 turn helical (left hand) from some copper wire and supported it with a dowel by threading the thing through the holes. It's amazingly simple but it works.

 

[mikie333]

like the origional post...i'm also new to satellite scanning...i was just at Space Camp, ACTUALLY advanced space academy and we did satelite monitoring...we had a little yassou scanner and this interesting antenna. the antenna we used was quite interesting, and one i have never seen before. It had 2 'antennas' on one mast. One was a 2m and the other was a 70cm. But it was a 'square' style. On the top, the 2m had a cable going around in a square and below (the 70cm) had a smaller square of cable. Has anyone seen this style before? (to toggle between the 2 different antennas, each had its own independant bnc cable comming out of it)

it worked pretty well for the satellite we were monitoring. In the end, we found the fq. online, found where it would be in the sky, aimed it right, and we picked up a few seconds of morse code.

 

[N4JNW]

You were monitoring AMSAT..

SOMETIMES.... you can hear AMSAT with nothing more than a duckie...