UHF Satcom Antenna from Antennas.us - Any Experience? Opinions?

[Merovingian]

Not sure if this goes here or not but since it is an antenna question and it is for receiving signals I decided to post here.

I would like to listen to transmissions from the various satcom satellites using my scanner or SDR radios 240-270MHz. I was wanting a ready to use Satcom antenna that can receive from any of the satellites in view. I was looking at the UHF Satcom antennas from Antennas.us, they look good, simple sleek and robust.

UHF SATCOM antenna, UHF X-Wing Antenna (Mini, Midi and Full sizes)

UHF SATCOM Antenna (Mini, Midi & Full sizes), UC 3004 381, is a circularly polarized, small turnstile or X Wing, intended for UHF Satellite communication MUOS.

www.antennas.us

The price is pretty high though: UHF SATCOM Antenna, X-Wing, Rev. A, RHCP, Full Size, High Gain Mount, Black, $579.61. Then I'll want a bandpass filter: $144.21.

UHF SATCOM Filter

UHF SATCOM Antenna Filter, low insertion loss filter covering the range from 243-318 MHz for Military SATCOM operation.

www.antennas.us

Aside from the obvious high price, any opinions? Can I get a same or similar ready made antenna as good for cheaper? Has anyone bought from Antennas.us or used any of their antennas?

Thanks

 

[prcguy]

I've been curious about these antennas but have never run across one to play with. They are incredibly cheap compared to any other commercially made UHF satcom antenna where the typical X wing runs about $7k on up.

I don't think you want their X -wing for general purpose reception since it needs a ground plane under it and it has one lobe that points straight up. The satellites are not straight up unless you live on the equator and one is right above you. I think you would be better off with a surplus military unit which can be had for a couple hundred $$ and you would then be getting a $7k antenna for a fraction of the new price. A fat cross dipole over reflector on a small tripod base is the basic unit and some have a few director elements to increase gain.

I sold a bunch recently but am not sure I would part with any more but you never know. They turn up on Ebay for various prices, most which are ridiculous but some go for fair prices, you just have to check ever few days to see what the inventory is.

I've posted this pick before but here is some of my old satcom antenna collection.

 

[iMONITOR]

Not sure if this goes here or not but since it is an antenna question and it is for receiving signals I decided to post here.

I would like to listen to transmissions from the various satcom satellites using my scanner or SDR radios 240-270MHz. I was wanting a ready to use Satcom antenna that can receive from any of the satellites in view. I was looking at the UHF Satcom antennas from Antennas.us, they look good, simple sleek and robust.

Thanks

For non-critical applications why not DIY?

diy satcom antenna 240-270 MHz build make - Google Search

 

[iMONITOR]

I've been curious about these antennas but have never run across one to play with. They are incredibly cheap compared to any other commercially made UHF satcom antenna where the typical X wing runs about $7k on up.

I don't think you want their X -wing for general purpose reception since it needs a ground plane under it and it has one lobe that points straight up. The satellites are not straight up unless you live on the equator and one is right above you. I think you would be better off with a surplus military unit which can be had for a couple hundred $$ and you would then be getting a $7k antenna for a fraction of the new price. A fat cross dipole over reflector on a small tripod base is the basic unit and some have a few director elements to increase gain.

I sold a bunch recently but am not sure I would part with any more but you never know. They turn up on Ebay for various prices, most which are ridiculous but some go for fair prices, you just have to check ever few days to see what the inventory is.

I've posted this pick before but here is some of my old satcom antenna collection.

View attachment 100200

Those prices are insane! They're for the most part marketed toward the government/military and they have lots of our money to play with!

 

[prcguy]

Your link points to other people hosting my copyrighted project which first appeared in Monitoring Times magazine then was legitimately posted by me on RR. Why not just get it off RR?

For non-critical applications why not DIY?

diy satcom antenna 240-270 MHz build make - Google Search

 

[Merovingian]

I've been curious about these antennas but have never run across one to play with. They are incredibly cheap compared to any other commercially made UHF satcom antenna where the typical X wing runs about $7k on up.

I don't think you want their X -wing for general purpose reception since it needs a ground plane under it and it has one lobe that points straight up. The satellites are not straight up unless you live on the equator and one is right above you. I think you would be better off with a surplus military unit which can be had for a couple hundred $$ and you would then be getting a $7k antenna for a fraction of the new price. A fat cross dipole over reflector on a small tripod base is the basic unit and some have a few director elements to increase gain.

I sold a bunch recently but am not sure I would part with any more but you never know. They turn up on Ebay for various prices, most which are ridiculous but some go for fair prices, you just have to check ever few days to see what the inventory is.

I've posted this pick before but here is some of my old satcom antenna collection.

View attachment 100200

I will continue searching eBay for something similar. . . I looked for a long while this afternoon but only found directional antennas that were way more expensive.

I downloaded the article you posted a while back, it was very nice indeed! If I were to buy their antenna I was thinking of building a ground plane similar to the one you had in your instructions, except I would make mine round with a 2' radius instead of square. I would have to use small aluminum U channel or something as bracing for the mesh to give it some rigidity since mine would be mounted on a mast instead of the ground or a roof top.

I had thought about building your design, it seems relatively simple to build but I don't have much time to put into it which is why I was wanting something "ready made".

Your design had some coiled coax cable inside. Theirs seems rather compact, I'm wondering if they are using some sort of PC board instead of coax?

 

[Merovingian]

For non-critical applications why not DIY?

diy satcom antenna 240-270 MHz build make - Google Search

I would like to DIY if I had the time. If I started the project it might take weeks or months to finish, if I finish it at all. There have been very few DIY projects that I have started which I actually finished over the years, most of them ended up costing me more than if I had just bought something ready made. By the time I finish buying tools (saws, drill presses, bits, ect.) and the hardware (screws, wood, metal, ect.) and the hours I put into it I could have bought two of whatever it was that I was going to DIY and the result didn't look near as good.

 

[Merovingian]

Those prices are insane! They're for the most part marketed toward the government/military and they have lots of our money to play with!

Yeah, they are pretty high. I want something decent quality and semi compact like they are offering but I don't really need something combat hardened that weighs a ton either. It would be nice if someone made a light duty version of their antennas.

 

[iMONITOR]

Your link points to other people hosting my copyrighted project which first appeared in Monitoring Times magazine then was legitimately posted by me on RR. Why not just get it off RR?

I wasn't aware you had a copyrighted project and if it's posted here on RR already why didn't you enlighten us? All I did it performed a Google search looking for some less expensive alternatives.

 

[dlwtrunked]

Not sure if this goes here or not but since it is an antenna question and it is for receiving signals I decided to post here.

I would like to listen to transmissions from the various satcom satellites using my scanner or SDR radios 240-270MHz. I was wanting a ready to use Satcom antenna that can receive from any of the satellites in view. I was looking at the UHF Satcom antennas from Antennas.us, they look good, simple sleek and robust.

UHF SATCOM antenna, UHF X-Wing Antenna (Mini, Midi and Full sizes)

UHF SATCOM Antenna (Mini, Midi & Full sizes), UC 3004 381, is a circularly polarized, small turnstile or X Wing, intended for UHF Satellite communication MUOS.

www.antennas.us

The price is pretty high though: UHF SATCOM Antenna, X-Wing, Rev. A, RHCP, Full Size, High Gain Mount, Black, $579.61. Then I'll want a bandpass filter: $144.21.

UHF SATCOM Filter

UHF SATCOM Antenna Filter, low insertion loss filter covering the range from 243-318 MHz for Military SATCOM operation.

www.antennas.us

Aside from the obvious high price, any opinions? Can I get a same or similar ready made antenna as good for cheaper? Has anyone bought from Antennas.us or used any of their antennas?

Thanks

I have one of those mounted on a cheap camera tripod (I found a bolt the size of the hole in the bottom of the antenna and replaced the one of the tripod camera attachment part with it). I used the disk part of a discone between the two as the need "ground plane" (more of a reflector). Not exactly the right size but quite close. I do use it with a pre-amp. Works reasonably well and is much more rugged than the antennas prcguy posted in a photo which are better preformers of course (I have such also). Note that you probably do not need the filter. Also, the beam width of the antenna is quite broad as it was meant to be just vertical but I do aim mine using the camera mount on the camera tripod. At one time years ago, I used a 220 MHz Cushcraft instead with the elements cut shorter for the higher frequency. That worked well also-though linearily instead of circularly polarized.

 

[prcguy]

See post # 11 in this thread for the instructions. MT magazine UHF Satcom antenna project

I wasn't aware you had a copyrighted project and if it's posted here on RR already why didn't you enlighten us? All I did it performed a Google search looking for some less expensive alternatives.

 

[Merovingian]

Per post #17 on that page, if I were to order a RHCP antenna and put a ground plane under it then it would be a LHCP antenna instead of a RHCP as required?

 

[Merovingian]

I have one of those mounted on a cheap camera tripod (I found a bolt the size of the hole in the bottom of the antenna and replaced the one of the tripod camera attachment part with it). I used the disk part of a discone between the two as the need "ground plane" (more of a reflector). Not exactly the right size but quite close. I do use it with a pre-amp. Works reasonably well and is much more rugged than the antennas prcguy posted in a photo which are better preformers of course (I have such also). Note that you probably do not need the filter. Also, the beam width of the antenna is quite broad as it was meant to be just vertical but I do aim mine using the camera mount on the camera tripod. At one time years ago, I used a 220 MHz Cushcraft instead with the elements cut shorter for the higher frequency. That worked well also-though linearily instead of circularly polarized.

I had thought to maybe need to angle it toward the south instead of straight up. As Prcguy said it has a large lobe going straight up.

 

[prcguy]

If you got a RHCP antenna that had no ground plane then put it at the right height above a ground plane then you would make it a LHCP antenna. A circular polarized antenna will swap polarities when the wave gets reflected. One screw up along these lines that I heard of was a UHF satcom antenna molded into the skin of an aircraft and when the satcom radio didn't work and after a lot of troubleshooting they found the signals were bouncing off some metal stuff mounted under the antenna imbedded in the composite skin and it made the antenna into a LHCP.

Per post #17 on that page, if I were to order a RHCP antenna and put a ground plane under it then it would be a LHCP antenna instead of a RHCP as required?

 

[Merovingian]

If you got a RHCP antenna that had no ground plane then put it at the right height above a ground plane then you would make it a LHCP antenna. A circular polarized antenna will swap polarities when the wave gets reflected. One screw up along these lines that I heard of was a UHF satcom antenna molded into the skin of an aircraft and when the satcom radio didn't work and after a lot of troubleshooting they found the signals were bouncing off some metal stuff mounted under the antenna imbedded in the composite skin and it made the antenna into a LHCP.

I didn't know that. So I would need to order a LHCP version for when I mount it over a ground plane. . . I'm glad I found out before.

Thanks!

 

[dlwtrunked]

I had thought to maybe need to angle it toward the south instead of straight up. As Prcguy said it has a large lobe going straight up.

I do not disagree with him. The only significant benefit to pointing it might be for a satellite on the horizon.

 

[prcguy]

I would buy a complete antenna for what you need or at least tell the mfr what you want to do with it and make sure the end result will do what you want.

I didn't know that. So I would need to order a LHCP version for when I mount it over a ground plane. . . I'm glad I found out before.

Thanks!

 

[prcguy]

When designing and testing the MT magazine X-wing I compared it to a commercially made magnetic mount X wing over a ground plane. My version worked better than the $7k commercial version because all the UHF satellites are outside its main lobe which points straight up and my X wing has a modified lobe that favors roughly 20 degrees to 60 degrees above the horizon which is where you will find most UHF satellites from the US or similar latitude. If you specifically tilt and point the commercial version to a satellite it then works better than my version.

Here is what I used for comparison, although I used the ground screen from my version instead of the wifees car in the picture.



I can tell this is an old picture of mine as we haven't had a lawn in about 6yrs thanks to the So Cal water shortage. I miss that lawn.

I do not disagree with him. The only significant benefit to pointing it might be for a satellite on the horizon.

 

[paulears]

I'm amazed how a hobbiest would consider a commercial grade antenna for a leisure project like this. Do you need the strength, reliability and super construction? The ham satellite people have been doing this for a very long time - starting with the UHF slow scan satellites and weather stuff, and if you google bowties and turnstile antennas you'll find them totally DIY and dirt cheap. In essence a normal dipole has a broadly donut shaped capture area so once you get above 45 degrees or so, the performance drops off to virtually nothing overhead, so you mount the dipole horizontal, which gives a figure 8 pattern, with decent coverage upwards. Add another at right angles and it fills in the side nulls. They work great for satellites. Hams love the diamond X-30s and X-50s - less than $100. The commercial antennas that are usually single band and virtually the same performance can be 500+. The fibreglass is thicker. The parts will probably be stainless rather than aluminium, the SO239 will be an N and the thickness of mounting tubes 3-4mm thick wall tube rather than .75 or 1mm Ali. Performance wise - it means the Jaybeam commercial UHF one on my repeater is getting close to 30 years old now and still going strong.

 

[prcguy]

Why are you amazed? If I'm going to monitor VHF aircraft comms I would rather have the radios used by the FAA for this purpose over a consumer grade police scanner. If I'm going to monitor military comms I want the same radios used by the military that I'm trying to receive. If I can get my hands on a military UHF satcom antenna then that's what I'll use for that purpose and so on. What makes this hobby extra fun for me is hunting down and using exotic stuff as part of the monitoring hobby.

I'm amazed how a hobbiest would consider a commercial grade antenna for a leisure project like this. Do you need the strength, reliability and super construction? The ham satellite people have been doing this for a very long time - starting with the UHF slow scan satellites and weather stuff, and if you google bowties and turnstile antennas you'll find them totally DIY and dirt cheap. In essence a normal dipole has a broadly donut shaped capture area so once you get above 45 degrees or so, the performance drops off to virtually nothing overhead, so you mount the dipole horizontal, which gives a figure 8 pattern, with decent coverage upwards. Add another at right angles and it fills in the side nulls. They work great for satellites. Hams love the diamond X-30s and X-50s - less than $100. The commercial antennas that are usually single band and virtually the same performance can be 500+. The fibreglass is thicker. The parts will probably be stainless rather than aluminium, the SO239 will be an N and the thickness of mounting tubes 3-4mm thick wall tube rather than .75 or 1mm Ali. Performance wise - it means the Jaybeam commercial UHF one on my repeater is getting close to 30 years old now and still going strong.