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View Full Version : Potential vandalism in an urban environment..



W4GPL
12-02-2011, 05:46 PM
I recently moved to the 2 1/2 floor of a very urban area of Denver. The neighborhood is filled with interesting characters.. I'm able to hang a 'random wire' outside of my bedroom window (doesn't do much for transmitting, but it hears pretty well)..

My concern is that someone might try to yank the wire for the copper value.. This wouldn't be the end of the world, but unfortunately it's attached to a $1000+ radio. :P Does anyone know of a good easy release coax connector I could put on the end of my rig? Similar to Apple's laptop power cord? I'd obviously be concerned by how this might effect the signal quality..

Thoughts?

PA5COR
12-02-2011, 05:54 PM
If you only listen just get the wire in the center connector so that it easioly can be pulled out.
I have a PL259 plug that "clamps" on without screwing it on the SO 239 chassis part.
You can pull that one off without screwing it loose or on, just a quick tug and it's off.

Should be available there too, or if you are really in need i can send it up.

W4GPL
12-02-2011, 05:57 PM
I have a PL259 plug that "clamps" on without screwing it on the SO 239 chassis part.Interesting. I'm not sure I've seen those, do you have a part # or brand name?

N2CHX
12-02-2011, 06:05 PM
Is it just hanging from your window? If so, why not just cut the wire at a spot high enough off the ground that it can't be reached, then remove a couple of inches of insulation off the remaining ends and twist them together. That way, if someone grabs the end of the antenna the most they're gonna get is the bottom 10 feet, the rest will be left hanging above where they can reach it. You can even use some electrical tape to help keep moisture out, but the ends will still separate if the bottom section is pulled on.

N2CHX
12-02-2011, 06:08 PM
Interesting. I'm not sure I've seen those, do you have a part # or brand name?

http://www.packetradio.com/catalog/index.php?main_page=product_info&products_id=1876

W4GPL
12-02-2011, 07:00 PM
Is it just hanging from your window? If so, why not just cut the wire at a spot high enough off the ground that it can't be reachedFire escape.

Thanks for the connector suggestion, that should give me enough protection, especially if I disconnect every time the radio is off..

kf0rt
12-02-2011, 08:24 PM
Random wire? Wouldn't a simple banana plug/jack do the job? You could do strain relief with dental floss. (seriously)

BTW, this is kind of a serious concern. Had someone attach their truck to a sprinkler valve at work about two years ago to steal the brass. They left with nothing, but it cost about $4,000 to repair and the city of Westmonster probably lost 20,000 gallons of water in the process. (Have pics of the 30' geyser)

WØTKX
12-02-2011, 10:18 PM
Old school bannana plug and jack FTW!

Just for fun, have you tried using the fire escape itself as an RX antenna?

NQ6U
12-02-2011, 10:21 PM
Just for fun, have you tried using the fire escape itself as an RX antenna?

Or a would-be vandal as an TX antenna?

WX7P
12-03-2011, 01:19 AM
Does seem like enough copper to bother with. The creeps steal air conditioner condensers that cost thousands for $50 worth of copper. The types that steal copper are probably to dense to realize you're using copper wire.

I wouldn't worry about it too much.

W4GPL
12-03-2011, 01:28 AM
Well, though their motives are unclear, someone fucked with it already.. and it was only out the window for 12 hours. It could have simply been jerkface youths... to imply it would be stolen is potentially unfair.

In this particular circumstance, my rig was unplugged from the coax, so there was no harm, but had the rig been plugged in, there would have been some damage.

WX7P
12-03-2011, 01:32 AM
Well, though their motives are unclear, someone fucked with it already.. and it was only out the window for 12 hours. It could have simply been jerkface youths... to imply it would be stolen is potentially unfair.

In this particular circumstance, my rig was unplugged from the coax, so there was no harm, but had the rig been plugged in, there would have been some damage.

I should have been more clear. I think mindless vandalism is a greater threat than someone stealing the wire for grins.

W4GPL
12-03-2011, 01:37 AM
Yes. Either way, the concern is the same.

I don't want someone yanking my wire and having the rig fly out the window.. or damage the connector. Kelli's solution is probably what will work... thanks again. :)

NQ6U
12-03-2011, 01:46 AM
Borrow a 1500 watt amp, turn your radio to CW mode, then place the key and a comfortable chair in position to watch your antenna, sit down and wait. First time someone grabs the wire, key down. That'll learn 'em.

KC2UGV
12-03-2011, 07:44 PM
Maybe, if you don't feel like making a new cable with the QC end, make a pigtail with a RCA on one end, and a normal 259 on the other.

K7SGJ
12-03-2011, 09:07 PM
I used to use the push on PL259s on the service bench, they're nice but don't come off very easily. As mentioned above, the banana plug will work great. You really don't need the banana socket as the plug will fit into the center of an SO239, and comes out fairly easy if it gets yanked. If the fit is too tight, the plug can be squeezed a tad.

Happy_Hamer
12-05-2011, 08:53 AM
Have you seen this?


http://youtu.be/olh2RsuGQdQ

NQ6U
12-05-2011, 10:05 AM
Have you seen this?

Of course, that would be trash the first time he keyed up his rig.

K7SGJ
12-05-2011, 10:09 AM
But it would make a beautiful glow.

PA5COR
12-05-2011, 01:09 PM
Made an active antenna myself here last week, it's in the back of the yard, and 30 feet away from the inverted L now and then running 800 watts into the L.

Simple circuit, J310 fet, 10 mA current through it, BFR 96S ( 5 GHz transistor) as buffer, and 2n3866 as amplifier.
Old telescopic antenna and a splitter/feed from some scrap material, done.
With 10 mZ running through the J310 fet i could not detect any interference or mixing, i have the schematic here scrabbled down during building.

Did not desstroy it running max power with the L even when the active antenna was a few feet away from the L during testing.
It will not replace the L or the OCF antenna in reception, but it comes darn close and you can hide it better as a long wire.

Had my 2/70 antenna broken off the van this weekend and my wife's car scratched, yes, it happens here too.

WØTKX
12-05-2011, 02:27 PM
Yes. Either way, the concern is the same.

I don't want someone yanking my wire and having the rig fly out the window.. or damage the connector. Kelli's solution is probably what will work... thanks again. :)


Sometimes it's fun when somebody yanks yer wire. :neener:

I still think you should try using the fire escape, or get roof access.

n2ize
12-06-2011, 02:14 AM
Do what any sane person would do. Put a few thousand volts across it. That will send them a message when they grab it.

KK4AMI
12-06-2011, 06:40 AM
Would not hurt to bolt the radio down! Can't pull it out the window and if they follow the wire to its source, they can't steal it either.

W4GPL
12-06-2011, 06:45 AM
I still think you should try using the fire escape, or get roof access.The roof is a no-go, the HOA President is a real tyrant. He caught me up there smoking one night, he about threw me off the roof. I got a 15 minute lecture.. he's an ass.

The fire escape.. I dunno how well that'd work.

n2ize
12-06-2011, 10:30 AM
Yeah, those HOA's are bad news. Thank God I have never had to live under their kingdom. Meanwhile face, it... When the HOA is in ham radio is out. You might look into setting up a good mobile station.

W1GUH
12-07-2011, 01:26 PM
I second the banana plug.

For the wire, one suggestion is to use magnet wire. It's invisible and works very well. Plus it breaks easily and is cheap. #26 seems to be the gauge of choice.

And don't discount the possibility of transmitting. I know of a ham here in NY that uses a 30' foot random wire worked against ground and he gets out well enough on 40 to be a regular net control for ECARS, 7255. Of course, above 40, it'll be even better. The ground he uses is a radiator; that'll work fine.

The fact that you can hear well is very encouraging.

Good luck and have fun! Wish I could hear where I am.

Paul

W1GUH
12-07-2011, 01:28 PM
Yeah, those HOA's are bad news. Thank God I have never had to live under their kingdom. Meanwhile face, it... When the HOA is in ham radio is out. You might look into setting up a good mobile station.

Or..put a mobile antenna on your car and sneak coax into the shack. The old "hide it in plain site" solution!

n2ize
12-10-2011, 06:47 PM
I remember a place I was working in and one day our network went dead. We traced the problem to a missing section of ethernet cable that ran through a hallway along a wall and then down through a stairwell and eventually to a router downstairs. Somebody apparently needed some ethernet cable so they simply cut out 100-150 foot length of our cable and took it with them. They wound up replacing it with a wireless link.