View Full Version : man pack Sat Ant
brushingham.d
11-16-2010, 10:30
I have been working for a company that is now building a man pack sat on the move will cover the required freq ranges 225-350MHz and will clip on to your pack or directly to the radio. all of this is packaged into a mold and will fit in your pocket.
this antenna has gone through several testing phases and it is determined that it is ready for production, i was able to have it tested over seas and state side with the only failures coming when the take off angles was less then 25deg but at that angle there are not many antennas that will make it.
i have redesigned the elements so that they are rigged and will come back to their origanal position, and with a VSWR of 2.5:1 or less Avg.
this is not the end all be all it has taken the field expediant antenna and improved on the concept and packaged in a form fit factor and made it a durable antenna.
Surgicalcric
11-16-2010, 18:21
I know a couple guys who are interested...
PM sent.
I would love to test this out. PM inbound.
Looks a lot like a field expediant that was being used in Iraq. Basically a couple of connectors w/ a coat hanger shaped like a rams head soldered on. That one had to be cut to a specific freq though.
x/S
brushingham.d
11-20-2010, 08:56
i will post a data sheet on monday. this idea began in 5th sfg and i can't remember his name...(must be getting old) if you are on here then please im me so that i can send you one.
resonant evil
06-19-2011, 04:24
old post
I believe that is "electron"
LongWire
06-19-2011, 11:34
Hey brush,
You have any more of these to test?
Correct me if I'm wrong, but weren't you in the 1/5 commo shed the last few yrs of your career?
69harley
07-14-2011, 20:16
I have a couple of Brushinghams antennas in my office that he gave me last year.
They work as claimed. It does need an amplifier with at least 25 watts and and 11 db of receive gain. They do not yet have the circular polarization, but that is overcome with the amp.
Paragrouper
07-15-2011, 06:27
It looks like Shakespeare is the manufacturer of this antenna.
http://shakespeare-military.com/milantennashow.asp?t=100
Their contact information is here. (http://shakespeare-military.com/contact.asp)
69harley
07-02-2012, 08:47
I saw an RFQ for this on Fedbizops this morning. Looks like 3rd SFG(A) is looking to prucure a bunch of them.
Just looked at the current design on the manufacturers website. Still appears to be the same basic low-gain and not radial polarized desighn.
Does anyone know if Shakespeare fixed the polarization and extremely low-gain issues?
Paragrouper
07-04-2012, 17:46
I saw an RFQ for this on Fedbizops this morning. Looks like 3rd SFG(A) is looking to prucure a bunch of them.
Just looked at the current design on the manufacturers website. Still appears to be the same basic low-gain and not radial polarized desighn.
Does anyone know if Shakespeare fixed the polarization and extremely low-gain issues?
This is a simple center fed dipole antenna. If you look at the geometry of an X-blade, which provides right-hand circular polarization it is nothing more than two dipoles with some tricks in the feed network to obtain RHCP. Theoretical max gain for this antenna is 2dBi and is dependent on the ground plane to develop a good radiation pattern.
It's best advantages are the size, ease of deployment and the cost. If one was to use this in an area where you have a high look-angle WRT the satelite and no significcant obstructions the antenna should overcome the gain deficit and loses related to polarization mismatch and work fine. Outside of those conditions...
Maybe not so good.
69harley
08-05-2013, 18:59
Any feedback on these RamHead antennas yet?
Whitetip1115
08-08-2013, 01:57
I have done some limited testing in a-stan:
Dependent on ground plane, with connection to 152 and running a ping test, max results were at 40% without an amp. Didn't have an amp available to test it with.
69harley
08-08-2013, 05:57
What elevation does that shot typically call for? 40% seems pretty low to me. Do you think that is an acceptable strength, would you go across the FLOT with that as your primary?
Whitetip1115
08-09-2013, 02:13
What elevation does that shot typically call for? 40% seems pretty low to me. Do you think that is an acceptable strength, would you go across the FLOT with that as your primary?
Because it is a mantenna essentially your elevation would be parallel to the ground, assuming you have it attached to your kit or backpack.
It is really low, especially in A-stan where you can get a 100% with a 2055 pointing at the ground..
It's definitely lower than I would like and I would not run it as a primary, when it is just as easy to run a small handheld and a KDU making your sat shots near instantaneous.
I would however let a tertiary comms guy run it on his back to see if he can rx sotf comms while out on patrol.
69harley
08-09-2013, 04:22
Because it is a mantenna essentially your elevation would be parallel to the ground, assuming you have it attached to your kit or backpack.
It is really low, especially in A-stan where you can get a 100% with a 2055 pointing at the ground..
It's definitely lower than I would like and I would not run it as a primary, when it is just as easy to run a small handheld and a KDU making your sat shots near instantaneous.
I would however let a tertiary comms guy run it on his back to see if he can rx sotf comms while out on patrol.
I was asking about the calculated angle from the ground terminal (your antenna) to the satelite, i.e. on Bragg to hit the 105 bird the elevation is approx 47 degrees. This angle does not change with the type of antenna, it simply is what it is.
If you achieved a 40% loop back score in say Afghanistan, that would not be very good at all. Terrible in fact. But a 40% in Korea, were the required elevation is very low, would be much better.