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sfbaby1982
02-20-2007, 05:49
Hey all,

My team is looking for ways to relocate the antenna's via cables around their body kit for the MBITR's. We have had limited long term success with standard commercial connectors and RG58 Coax cable. The problem is that the connectors aren't made for the military environment and bending and flexing takes their tole. Sometimes I end up at night remaking 3 or 4 cables, every night! I'm looking for any ideas on ways to improve these connections through readily available commercial products or military specific products that can be purchased on a teams budget.

My idea is to use superglue under the crip sleeve, not in a quantity that would block the negative connection but would provied some antislip properties. My next thought was to overlap this with a piece of shrink wrap followed by a spring that was roughly 1 and 1/2" long and slightly larger than the RG58 cable covernig that in another sleeve of heat shrink tubing. The weaknesses that I can forsee would be the connector pulling out but I figure that could be defeated by putting a small depression in the crimp sleeve with a nail or small punch, just enough to penetrate the outer sleeve of the coax. Any thoughts.

R

I tried searching for this thread but haven't come up with anything else on it. Let me know where else I could look if you know otherwise.

deanwells
02-20-2007, 06:06
Have you talked to anyone in the EMS shop?
As for the cables, Have you used solder? Try a little bit of slack in the wire leading to the connector. Put the tension on another part of the wire, so when the guys go to pull them tight, they are only pulling part of the wire instead of the wire and the connector. Let me know the distance of range on those antenna's through a PM, I'm curious.

Eagle5US
02-20-2007, 06:30
The "Mantenna" has become quite popular when wovern in and out of the MOLLE webbing-but this is the first I have heard of problems with the connection. Once woven in-the thing is super stable.
I may not be understanding where you are experienceing the weak point.:confused:

Eagle

Snaquebite
02-20-2007, 06:33
Not a commo guy, but check with these guys maybe they can offer advice.

Info: http://www.tacticalcommand.com/support/mast_info2.pdf

Please contact TCI / don@tacticalcommand.com for further information.

The Reaper
02-20-2007, 08:51
I would have to second the recommendation for Don and TCI.

Great people to deal with, very pro military and LE.

TR

sfbaby1982
02-20-2007, 10:17
Thanks to all for that quick response. We're about to hit some CQC shooting sessions and this is going to become an issue.
The "Mantenna" has become quite popular when wovern in and out of the MOLLE webbing-but this is the first I have heard of problems with the connection. Once woven in-the thing is super stable.
I may not be understanding where you are experienceing the weak point.

The problem with that usually isn't with the antenna end of things. It usually arrises from the cable comming out of the TNC connection on the radio itself. Using a 90 degree bend helps but it causes the radio to increase its bulk factor by alot.

Not a commo guy, but check with these guys maybe they can offer advice.

Info: http://www.tacticalcommand.com/support/mast_info2.pdf

Please contact TCI / don@tacticalcommand.com for further information.

&

I would have to second the recommendation for Don and TCI.

That looks exactly like what I need. I'm going to get in touch with them as soon as I get back into the states. Again much appreciation. As far as the EMS shop goes they mostly just have the regular connections that we have on the teams. I'll give them another shot and see if I get some different results this time:rolleyes:

R

Para
02-25-2007, 11:21
I think you need to look at where the guys are keeping the MBITR's at on their kit. What and how is it getting snagged that is causing it to rip the cable out? My guys wear the radio on the front non-firing side of their bodyarmor routed onto their backs. To date I have only had one guy need his cable replaced and he was the turret gunner. For the life of me, I can't see what they would be doing that would be that harsh on the equipment. You may need to tell them to take better care of their equipment or lose the convenience, i.e. put them on an Echo timeout. As my Delta says, "I don't treat stupidity."

Electron
07-16-2008, 05:16
I'm an EMS Shop supervisor. My thoughts on the cable connector stability: When you are assembling the BNC connector (using the crimp or manual assy), check the continuity of your work (ohm the cables), then fill the interior of the connector with hot glue just before you crimp the connector. Shrink wrap tubing and/or electrical tape will only serve as a moisture barrier, not a strain relief. Once dried and cool, the glue will serve as a moisture barrier and as strain relief. RG-58 is a very durable cable. If your cable is subject to a lot of bending you might want to consider using a stranded core instead of a solid core.

Most important of all, don't use your antennae as a carrying handle for your radios. I replace more antenna connectors than anything else on radio systems.

steelcobra
09-08-2008, 13:02
I've yet to have anyone come back to us for repairs/replacement of any of the antennas we've given out. There's nothing particularly special, either. Solder the pin to the inner conductor, make sure you have the outer sleeve fully wrapped around the pipe on the plug so the crimpers crush the three together, and make sure you have some of the outer insulation pinned under the sleeve.

Are you using decent crimpers with a die for RG58? If the aren't crimped down tight enough, that may also cause issue.
http://www.lane-pilot.com/servlet/Detail?no=45
We use these. They're expensive, but do a PERFECT job.

And, as said before, how are they routed that they are getting pulled out so often?

AirborneAndy502
12-31-2010, 11:50
Hey gents, I'm in Afghanistan and we're trying to figure out the whole body antenna thing. Our MBITR's suck when it comes to range, and the blade antenna is our old standby but it always gets in the way. We have requested RG-58 cable but our commo guys and supply don't support us. My buddy ended up cutting a RG223? cable the same way one of the other threads said to and it works pretty good. My question for anybody who is good with the radios is when you weave the antenna on your kit, does it have to be exposed or can it be woven under a back panel and does it need to be woven up and down as long as possible? They still get really good range but every now and then we run into problems with it.

glebo
01-01-2011, 05:43
I've heard/seen antennas oriented horizontaly, like a doublet (commonly used for HF). What you have to remember is, line-of-site is predominantly vertically polarized EM energey, meaning, your antenna should be vertical, or straight up and down....if possible.

You will get some signal off of antenna that is woven through kit, but the more the antenna touches, the more loss it will have reducing com distance.

Weaving antenas through kit or whatever may work ok in urban environments due to the proximity of stations (soldiers), but if ya wanna reach out, then you have to insulate the antenna from any grounding possibilities. Your body is pretty much absorbing most of the energy radiated off of the antenna.

Stay safe, thank you and your guys for what you are doing....and good luck..

rocketjok
01-01-2011, 17:34
The COM201B comes with a nifty little splitter that attaches to the MBITR and allows you to attach a BNC connector horizontally which reduces the stress on the end of the cable because it does not have the bend if ran horizontally. I was having the same problem with connectors shitting out on me and that has helped.

On the placement of the antenna I have found that putting a blade antenna in my extra pop flare pouch with the antenna bent twice so that it is lower then my shoulder works very well. I can just reach over my shoulder and grab the tip of the antenna and pull it out to fully extend my antenna, it also keeps the antenna vertically polarized. I mount the pouch on my back and run the cable through the bottom of the pouch through the drain vent. I am at my VSO site and when i get some time i will take pictures and drop the NSN for the splitter.

I have been experimenting with taking a BNC barrel connector and pushing it into the base of the AN/PRC 119 long whip and running a cable to my mbitr in place of having to hump both the mbitr and the 119. I have had limited success, I don't think it grounds as well as when actually plugged into a 119. The problem i have is that our AO is urban and mountain desert so no trees. I need a antenna that can be quickly erected and taken down from a roof top. Does any one have any ideas for home made antennas that would work?

hotshot
01-01-2011, 23:53
Hey gents, I'm in Afghanistan and we're trying to figure out the whole body antenna thing. Our MBITR's suck when it comes to range, and the blade antenna is our old standby but it always gets in the way. We have requested RG-58 cable but our commo guys and supply don't support us. My buddy ended up cutting a RG223? cable the same way one of the other threads said to and it works pretty good. My question for anybody who is good with the radios is when you weave the antenna on your kit, does it have to be exposed or can it be woven under a back panel and does it need to be woven up and down as long as possible? They still get really good range but every now and then we run into problems with it.

Andy,
Are you referring to cutting the cable to a frequency? I'm not a commo guy, but from my experience, and based on your location. The antenna weaved through your kit has 2 major cons. 1- It limits you to only one frequency. 2 - The range is diminished considerably. I have always used a blade antenna neatly folded and bound with a velcro loop. This allowed me to extend it easily (As someone else mentioned in this thread). Good Luck.

CH

kollkash
02-14-2011, 10:54
Hey gents, I'm in Afghanistan and we're trying to figure out the whole body antenna thing. Our MBITR's suck when it comes to range, and the blade antenna is our old standby but it always gets in the way. We have requested RG-58 cable but our commo guys and supply don't support us. My buddy ended up cutting a RG223? cable the same way one of the other threads said to and it works pretty good. My question for anybody who is good with the radios is when you weave the antenna on your kit, does it have to be exposed or can it be woven under a back panel and does it need to be woven up and down as long as possible? They still get really good range but every now and then we run into problems with it.

Not sure if you're still "experimenting" or in need but here's some thoughts. I tend to agree with both of the following:

On the placement of the antenna I have found that putting a blade antenna in my extra pop flare pouch with the antenna bent twice so that it is lower then my shoulder works very well. I can just reach over my shoulder and grab the tip of the antenna and pull it out to fully extend my antenna, it also keeps the antenna vertically polarized. by rocketjok

and

1- It limits you to only one frequency. 2 - The range is diminished considerably. by hotshot

If you're weaving any antenna on your kit, you WILL experience degradation of the signal. Bottomline, the more exposure you can afford, the better LOS you will have. Also, consider the number of connectors you might use--each connector contributes to additional loss. The best solution is to place the radio on your kit so that the OEM long-whip antenna (which is designed for maximum VSWR readings for a wide-range of frequencies) doesn't impede too much with your ability to operate effectively. If you have the RCU (remote control unit) you might even be able to mount it behind you (out of he way) and run the long-whip up one of your shoulders with the ability to extend the antenna in weak signal areas. You might consider weaving the long-whip antenna within your kit with a short transmission line connecting it to your MBITR (just consider note above regarding connectors and loss).

Ultimately, you have to decide what is more important--clear, reliable comms or convenience.

BleepAndBloop
03-16-2012, 13:16
I built some of the relocation cables for the blade for some guys on my team out of coax cable. I took a few steps to strengthen them:

1) Crimp and solder the inner pin
2) I make sure that when I am pushing the connector on I feel that little snap and know that it is seated all the way.
3)Crimp the sleeve not just once (leaving a little collar) but a second time so that it is fully crimped to the cable.
4) Shrink wrap that reaches a 1/4" past the sleeve
5) SHOW people how to run the cable if they haven't done so before. How to make it not too tight but not too loose.

I have only had one break that I have built thus far and that was my first attempt making them in SAGE.

As for the body whip I tried them for a bit and from what I was taught they use your body as a reflector to push the signal outward. So ideally you want the body whip as close to your body as possible and if you are running it in and out of a plate carrier it is not only farther from your body but also has a buffer inbetween hindering the signal.
Issue two with the body whip is that it is a LOS and you do not have the ability to extend it (unless you unweave it) to increase your LOS distance where the whip you can unvelcro (or rubberband if you lost or ripped your velcro) and extend it to the full length increasing your LOS.

If we are doing things in buildings I will run a bodywhip on my kit. But if we are out and about on patrol or just walking I run the whip (relocated on the back of my kit).

I hope this helps a bit. Just my experience.