PRC-150?

[bravo22b]

Originally Posted by albeham

There is a lot to say when it comes to NIVIS, back-pack comms.

Your going in the right direction, continue to think outside the "BOX'.

I run 5 watts, yep 5 watts with a " End Fed Antenna" 1/2 wave long.

It acts like a dipole, but you feed it at the end, so there is no coax to carry. I do some hiking, and like to have a lighter load then my old commo ruck.

Getting the Far end up above 5 feet, and using low frequencies , 10 MHz below, gets me a NIVIS shot, and if you get it up high 10 feet or more, and with the right high band frequencies, you can talk a hell of a lot further then you think.

When you use a short whip, you are asking the tuner to load the antenna, this could cause your antenna to be ineffective for what you are trying to do, but if it works go with it.

I would use the 16 foot whip, on its side, like what has been said. A vertical gives you ground wave, a horizontal antenna gives you sky-wave. Keep the antenna off the ground, so not to complete the path to ground, that's what you are asking the sky to do for you.

There is a great book out, that was written by a NG O,,"Near Vertical Incidence Sky wave Communications" Its a Ham radio book. But then again we are all Amateurs..

I have a lot more to tell you if you want it, email me, etc.

A radio man is the life line to the team, shooting a gun is nice, but I like to get a ride home, not walk..

ASk away.... AL

PS We did a lot of NIVIS stuff while on the GMV, while on the move..

Cool stuff. I am going to try to digest this info and do some more research... I'm not looking to be spoon fed.

At the same time, more info is always good.

A happy coincidence that we've got two SF commo gurus both in MD... which just so happens to be where my unit is (Hagerstown). Maybe at some point I can repay your kindness with some food & drink on me...

[albeham]

I am good with that.

I work at Fort Meade.

Its a Ham thing be glad to help you.


AL

[Ret10Echo]

Originally Posted by bravo22b

Cool stuff. I am going to try to digest this info and do some more research... I'm not looking to be spoon fed.

At the same time, more info is always good.

A happy coincidence that we've got two SF commo gurus both in MD... which just so happens to be where my unit is (Hagerstown). Maybe at some point I can repay your kindness with some food & drink on me...

I am good with that.

I work at Fort Meade.

Its a Ham thing be glad to help you.


AL

The fact that we know each other is also somewhat coincidental too.

Thanks for stepping up AL and keeping me straight.

[albeham]

Hey its cool, i don't know everything, hell just ask my wife!!!!


AL

[Badger52]

Originally Posted by albeham

I am good with that.

I work at Fort Meade.

Its a Ham thing be glad to help you.


AL

First, thanks for your contributions to this thread as well as Ret10Echo's and others. I'll personally vouch that the search engine is still working just fine. Good field-tested info provided herein and better than a new thread.

Being one who would rather have less gear/more Ramen I can vouch for the end-fed wire with some counterpoises, either as a simple/cheap/lightweight setup that has gotten me nearly 1K miles on my 5w, or to solve that other problem:

Can talk x-country but not the friend 95 or 150 miles away. That is where I found there wasn't a substitute for making some research/work investment on the front-end. There are squiggly lines to interpret & a bit of math to do. (Of all the various service field handbooks, the USMC seems to be the best of the bunch.)

Have also learned (with chagrin) that in my climate it's useful to insure in the morning that the counterpoises are still looking up at the world, rather than the night's heavy snowfall.

I am curious to see if bravo22b has some follow-up as to how the various bits of advice worked out for his particular requirement that started the thread.

Thank you again.

[bravo22b]

I am curious to see if bravo22b has some follow-up as to how the various bits of advice worked out for his particular requirement that started the thread.

There is another thread that has some more good info, and also summarizes the results of a COMMEX we had with the 150.

http://www.professionalsoldiers.com/...ad.php?t=30107

Since this thread, I have had a chance to do more work with the 150 on shorter range stuff as well.

My unit has a COMMEX this coming weekend with the Georgia LRS unit. I will be busy with other things but I will get some feedback on how it goes and what freqs and antennas they use.

I still owe Albeham and Ret10Echo some food and beer. Gentlemen, I am doing the Army's work full time now, you let me know when is a good time.

[Badger52]

Originally Posted by bravo22b

There is another thread that has some more good info, and also summarizes the results of a COMMEX we had with the 150.

My unit has a COMMEX this coming weekend with the Georgia LRS unit. I will be busy with other things but I will get some feedback on how it goes and what freqs and antennas they use.

Trackin', thanks.

[albeham]

Any update to this? Would like to hear how it turned out for you all.


AL


PS JOTA

[2018commo]

My favorite for NVIS was a slant wire with a teaser to adjust TO angle and a terminating resister at the end of the counterpoise. Worked well in the winter out west and the Flintlock/ Reforger trips in Europe. Did one on a 77 in Pathfinder School and talked to Lawson Airfield from the LZ at Darby. The guys with the Bert and Earnie haircuts were scratching their heads and yes it was a good day to be SF!

[bravo22b]

So this summer my unit spent three weeks in Australia for Talisman Sabre 2011. Our teams conducted missions that ranged from 30-70 km away from our COB. Primary means of communication was HF with the 150, with some teams having TACSAT for alternate means using MBITR's.

We had to beg, borrow, and steal the equipment we needed to make this work, but we were able to come up with a limited number of Toughbooks, and we had enough MBITR's for two per team, and a handful of TACSAT antennas. One of our best assets is actually one of our E-5 riggers, who works for the State Department as a commo guru, and took charge of our commo section for this exercise.

One of the biggest limitations we had was batteries. We were unable to get 5590 adapters for the Toughbooks, so as anyone who has ever used one knows, battery life is very limited. Also, the 5590s that we took for the 150 were old and did not have their full life expectancy. For MBITR's, we had a limited number of rechargeable batteries and again no 5590 adapters.

My team spent 5 days out without resupply and battery life was definitely a major concern. The Toughbook lasted about 1.5 days using Tac Chat, and then we had to go to digital voice. The MBITR's lasted the whole time, but only because we only used them during commo windows and I used the 150 to monitor FM for intra-team communications most of the time. I also kept one MBITR battery in reserve so that we would have TACSAT for emergency use.

On the HF side, we used mostly the Harris RF-1940 antenna, with a field expedient antenna for a backup if necessary. Operation was in 3G mode. One issue we kept running into was the radio losing its TOD sync. I am not sure what was causing it to lose sync so quickly, but in about a 12 hour period we were losing it. This caused a problem during our first commo window because we had lost sync completely, so could not do an LQA to try to get our antenna configuration worked out. We had to resort to using TACSAT for our first commo window and doing a manual TOD reset.

Once that issue was resolved we had fairly good success during the rest of our mission using HF. We experimented with different antenna configurations and concluded that a dipole approximately 5' off the ground using the Harris antenna was the best configuration. We experimented by reproducing that configuration using our field expedient claymore wire dipole, and interestingly enough, it actually had a better LQA score on our best channel at that time, but dramatically worse on the other channels. Given the transmitting distance I am fairly confident that we were using NVIS and not a ground wave.

It was excellent training for us. My RTO and ARTO got a lot of practice setting up the antennas and using the radios, became fairly proficient at using the Toughbook and TAC Chat, and came to understand a little bit of the complexity of using HF. They recorded LQA's at each commo window and got to see how the link quality went up and down for different channels based on the time of day, so now they have a better understanding of that aspect of HF.

All in all, we feel like we accomplished a lot during that exercise. All teams made HF comms during their missions, and most if not all teams had some success with TAC Chat and sending some digital imagery of their NAI back. Considering that we are talking about NG 11B's who do not do this every day and have limited experience with this equipment, I think that qualifies as success.

Our key take aways, some of which may be obvious to an 18E, but nonetheless:

5590 adapters are a must for long missions
PCC/PCI's - radio checks not just the morning of the mission, but immediately before moving out
The importance of PACE (or at least PA)
Trying to transmit lots of information on digital voice sucks
The importance of adjusting your HF antenna to get the best results

Hope some of this helps somebody else.

[Ret10Echo]

Originally Posted by bravo22b

Our key take aways, some of which may be obvious to an 18E, but nonetheless:

5590 adapters are a must for long missions
PCC/PCI's - radio checks not just the morning of the mission, but immediately before moving out
The importance of PACE (or at least PA)
Trying to transmit lots of information on digital voice sucks
The importance of adjusting your HF antenna to get the best results

Thanks for the post bravo...Can't help but notice that some things never change....

[Traweek]

Originally Posted by Ret10Echo

Thanks for the post bravo...Can't help but notice that some things never change....

With that little AAR it looks like he will be ahead of the game next time.... and some things never change.... except weight, things seem to be getting heavier now-a-days

[Ret10Echo]

Originally Posted by Traweek

With that little AAR it looks like he will be ahead of the game next time.... and some things never change.... except weight, things seem to be getting heavier now-a-days

Don't get going about weight....(her come the FOG's)

Considering the days of the PRC-70, G-76s, BB-542s and DMDGs...and P-A-C-E meaning different pieces of hardware (as opposed to different modes of comm that may reside in the same metal case)

Heavy is relative...

[Badger52]

Originally Posted by bravo22b

Once that issue was resolved we had fairly good success during the rest of our mission using HF. We experimented with different antenna configurations and concluded that a dipole approximately 5' off the ground using the Harris antenna was the best configuration. We experimented by reproducing that configuration using our field expedient claymore wire dipole, and interestingly enough, it actually had a better LQA score on our best channel at that time, but dramatically worse on the other channels. Given the transmitting distance I am fairly confident that we were using NVIS and not a ground wave.

It was excellent training for us. My RTO and ARTO got a lot of practice setting up the antennas and using the radios, became fairly proficient at using the Toughbook and TAC Chat, and came to understand a little bit of the complexity of using HF. They recorded LQA's at each commo window and got to see how the link quality went up and down for different channels based on the time of day, so now they have a better understanding of that aspect of HF.

Good stuff, thanks for the follow-up. Sounds like you also had the opportunity to play with different heights above ground and that can be very illuminating.

[bravo22b]

So it is that time of year for us again, our LRS teams are going out for an urban surveillance FTX. Primary comms will be HF with the 150 as in the past. Distance of the HF shot will be appx. 115 km.

Over the past couple years we have built up a good basic level of skill using dipoles, but given the goal of setting up an antenna in an urban environment and staying concealed, that does not seem like the best choice. I'm not saying that you cannot set up a dipole and keep it concealed in a real city given the time and materials, but it is probably not practical given the time and material constraints we are operating under. In addition, the training venue is a MOUT site, and there is not a lot of existing wires, clotheslines, or the like that you could conceal an antenna alongside.

I have done some research, in particular an article in the spring 2004 edition of Army Communicator called "AN/PRC-150HF Radio in Urban Combat" which has a lot of good info.

I have used a field expedient square loop antenna once in the past successfully, and I plan on trying that again. I would be interested to hear any other suggestions on good techniques for urban HF. Our constraints are basically that we can't afford to buy new gear, so we will be using either the 10' whip, Harris RF-1940 antenna, or field expedients.