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K9CCH
07-17-2013, 06:35 PM
I bought a 10' section of 1/2" copper pipe with all the fittings. I got everything soldered together and its sitting in the living room waiting to be mounted. Before I go any further I have a few more questions.

1.) I have purchased the PL-259 UHF connector, which will be soldered to copper pipe clamps. What is the best connecting material to go from the PL-259 to the short part of the J pole? Can I just strip a piece of 18 guage copper speaker wire, or do I need something more solid?

2.) There is an old satellite dish on my roof, leftover from the previous owners. Is it ok to mount the J Pole to this mast if I take the dish off? I was thinking that I would mount the J Pole to a 3" wooden dowel and then mount the dowel to the mast for a little extra added height.

3.) The satellite dish has a ground wire that is ran from it, to a metal strap that is connected to the metal utility pole that my electric meter is on. Can I keep that ground in place? Since the mast is screwed into the roof, I'm very paranoid about lightning hitting it. (I assume I'll know more about this once I get into reading the antenna book, but for now y'all are what I have to go on.)


Thanks in advance for any suggestions.

NQ6U
07-17-2013, 06:48 PM
Here's how I do it:

10060

Get yourself four 1/2" copper pipe clamps. Flatten two of them in a vice, then drill a third hole in them using the unflattened ones as a guide. Use brass screws and nuts to bolt the clamps to the antenna and tuning stub tight enough to keep them from sliding down but not so tight that you can't move them. Bolt or solder the base of a SO-259 to one clamp, then run a length of 14 AWG solid copper wire from the center conductor pin to the other and solder it. Adjust the assembly up and down until you reach minimum SWR, then tighten the screws. Ideally, you should solder the clamps in place to the antenna but I never do and haven't run into any trouble so far.

As far as the grounding goes, j-poles are supposed to be connected to a DC ground. For reasons that I am unable to fathom, though, mine always seem to work better when they're mounted on a non-conductive mast and grounded with a wire or strap. YMMV on that one, of course.

K9CCH
07-17-2013, 07:04 PM
Here's how I do it:

Get yourself four 1/2" copper pipe clamps. Flatten two of them in a vice, then drill a third hole in them using the unflattened ones as a guide. Use brass screws and nuts to bolt the clamps to the antenna and tuning stub tight enough to keep them from sliding down but not so tight that you can't move them. Bolt or solder the base of a SO-259 to one clamp, then run a length of 14 AWG solid copper wire from the center conductor pin to the other and solder it. Adjust the assembly up and down until you reach minimum SWR, then tighten the screws. Ideally, you should solder the clamps in place to the antenna but I never do and haven't run into any trouble so far..



Thats EXACTLY what I was planning on doing. I just didn't know if regular multi strand wire would work, or if I needed the solid stuff.





As far as the grounding goes, j-poles are supposed to be connected to a DC ground. For reasons that I am unable to fathom, though, mine always seem to work better when they're mounted on a non-conductive mast and grounded with a wire or strap. YMMV on that one, of course.




That's what I was thinking I'd put the length of wooden down in there for. Or PVC, one or the other. I just didn't know if it was safer to KEEP the ground, or remove it.

W3WN
07-18-2013, 10:58 AM
No reason at all that you can't use the old SatDish mount.

My ARX-270 is mounted on the side of the house using one of those.

kb2vxa
07-18-2013, 01:50 PM
One thing I noticed, the Pope's flange mount SO-239 isn't waterproofed, at least not the way I do it. First, a short 1/8" wide copper strip has greater surface area than a wire so greater conductance at VHF. Once soldered into place on the SO-239 center pin a healthy glob of silicone bathtub caulk over the whole insulator to seal that side, then black vinyl tape to seal the PL-259 side. I do it military style, starting an inch or so down the coax tight spiral wrap up to the flange stretching slightly as you go. Then a turn to cover the remaining open threads completely and spiral wrap back to the starting point. Then to finish it off a couple of slack turns so when the tight wrap contracts a bit they take up the tension and don't unwrap leaving tape flapping in the breeze. I've been doing it this way for decades and never had a leak or flapping tape. That Coax Seal black putty is crap, before long it weathers and cracks letting moisture in. I had to replace coax and hardware and reseal several of those messes that left others wondering what went wrong.

Yeah, keep the ground for safety, otherwise a bolt would take the path of least resistance, the coax into your shack. One caveat, often installers use aluminium "grounding wire" like the stuff Rat Shack used to sell. I remember removing a 6M ground plane from the house of an SK and found the aluminium had corroded almost all the way through and the metal was brittle as glass, it crumbled in my hands. If that's the case I'd replace it with 8ga bare solid copper used for grounding the neutral bus in an electrical service entrance panel. Just trot down to your local supply house and talk to the counter person, they'll fix you right up and supply any clamps you may need, bronze is best and all is up to code.

Don't sit under the apple tree when the sky is flashing
When the sky is flashing
When the sky is flashing
NO NO NO don't sit under the apple tree when the sky is flashing
Or it'll burn you to the bone

Sorry ladies, sometimes I just can't help myself.

NQ6U
07-18-2013, 02:26 PM
As far at the waterproofing goes, I used an N connector on that antenna. They are intrinsically waterproof. I did add a blob of silicone to the rear of the female connector but it doesn't show up on the photo.

K7SGJ
07-18-2013, 09:11 PM
One thing I noticed, the Pope's flange mount SO-239 isn't waterproofed, at least not the way I do it. First, a short 1/8" wide copper strip has greater surface area than a wire so greater conductance at VHF. Once soldered into place on the SO-239 center pin a healthy glob of silicone bathtub caulk over the whole insulator to seal that side, then black vinyl tape to seal the PL-259 side. I do it military style, starting an inch or so down the coax tight spiral wrap up to the flange stretching slightly as you go. Then a turn to cover the remaining open threads completely and spiral wrap back to the starting point. Then to finish it off a couple of slack turns so when the tight wrap contracts a bit they take up the tension and don't unwrap leaving tape flapping in the breeze. I've been doing it this way for decades and never had a leak or flapping tape. That Coax Seal black putty is crap, before long it weathers and cracks letting moisture in. I had to replace coax and hardware and reseal several of those messes that left others wondering what went wrong.

Yeah, keep the ground for safety, otherwise a bolt would take the path of least resistance, the coax into your shack. One caveat, often installers use aluminium "grounding wire" like the stuff Rat Shack used to sell. I remember removing a 6M ground plane from the house of an SK and found the aluminium had corroded almost all the way through and the metal was brittle as glass, it crumbled in my hands. If that's the case I'd replace it with 8ga bare solid copper used for grounding the neutral bus in an electrical service entrance panel. Just trot down to your local supply house and talk to the counter person, they'll fix you right up and supply any clamps you may need, bronze is best and all is up to code.

Don't sit under the apple tree when the sky is flashing
When the sky is flashing
When the sky is flashing
NO NO NO don't sit under the apple tree when the sky is flashing
Or it'll burn you to the bone

Sorry ladies, sometimes I just can't help myself.

Uhh, I think they were singing "Boogie Woogie Bugle Boy of Company B" in that snippet. But, then again, there is every possibility I could be full of shit.

mw0uzo
07-19-2013, 12:19 PM
the Pope's flange

:clap::lol:

kb2vxa
07-19-2013, 12:41 PM
Well, I DID say it's not waterproofed the way I do it. (;->)

Yup, the still is from Buck Privates (Abbot & Costello) and that was the performance of Boogie Woogie Bugle Boy. I chose it because they look better in uniform, especially custom tailored uniforms like Eric Estrada in CHiPs. (;->) http://www.youtube.com/watch?v=qafnJ6mRbgk Notice that salute comes at the very end of the performance.

"But, then again, there is every possibility I could be full of shit."

We always knew you were full of something, now we know what it is. (;->)

K9CCH
07-19-2013, 01:21 PM
Sometimes I feel like I'm naked and everyone can see me.... Or that I missed my round of medication and y'all are all laughing.


Bugle boy, Chips, Popes.....WHAT? LOL

W3WN
07-19-2013, 02:32 PM
Sometimes I feel like I'm naked and everyone can see me.... Or that I missed my round of medication and y'all are all laughing.

Bugle boy, Chips, Popes.....WHAT? LOLWell, you're new here, and some of our regulars are using shorthand again.

Bugle boy: See the picture in Post #5? The Andrews Sisters performing the song "The Boogie Woogie Bugle Boy of Company B" from the Abbot & Costello movie Buck Privates.

CHiPS: Popular TV show on NBC from 1977 to 1983, starring Eric Estrada, playing a California Highway Patrol motorcycle riding officer. Of course, his custom-tailored costume looked a heck of a lot sharper than the off-the-rack stuff the regular CHP officers wore (no offense to CHP intended).

Pope: KJ6BSO is the IoMH Pope. Long story. Just accept it. And have another drink at the bar. It helps.

mw0uzo
07-19-2013, 04:36 PM
Sometimes I feel like I'm naked and everyone can see me.... Or that I missed my round of medication and y'all are all laughing.


Bugle boy, Chips, Popes.....WHAT? LOL

It's ok. I barely have any idea about a lot of stuff that goes on here. Your medication was delicious.

NQ6U
07-19-2013, 06:45 PM
Pope: KJ6BSO is the IoMH Pope. Long story. Just accept it. And have another drink at the bar. It helps.

I'm no longer sure exactly how it happened myself.

W3WN
07-19-2013, 07:23 PM
I'm no longer sure exactly how it happened myself.
Well, you were the Bishop of the Antelope Freeway. Then the Cardinal of Langerhans. Then there was this big Conclave...

... what's a Conclave?...
... it's a big building full of Cardinals, but that's not important right now...

... then there was black smoke, black helicopter smoke, black taco smoke, black crematory smoke (don't ask), and then there was white smoke, and there you were, on the balcony, blessing SX-88's and pink Motorola APU's.

K7SGJ
07-19-2013, 09:27 PM
Well, you were the Bishop of the Antelope Freeway. Then the Cardinal of Langerhans. Then there was this big Conclave...

... what's a Conclave?...
... it's a big building full of Cardinals, but that's not important right now...

... then there was black smoke, black helicopter smoke, black taco smoke, black crematory smoke (don't ask), and then there was white smoke, and there you were, on the balcony, blessing SX-88's and pink Motorola APU's.

Jesus Christ. I understood every bit of that.

NQ6U
07-19-2013, 09:39 PM
Jesus Christ. I understood every bit of that.

Sadly, I did as well. I think we both need to get a life.

K7SGJ
07-19-2013, 09:42 PM
Sadly, I did as well. I think we both need to get a life.

I'll pick you up at 0500 and we'll go looking.

NA4BH
07-19-2013, 09:47 PM
I'll pick you up at 0500 and we'll go looking.


This went from technical to "Island Speak" in about 3.5 posts. GOD I love this place.

Pick me up too, I'll spring for the biscuits.

And I forgot :rofl: :rofl:

NQ6U
07-19-2013, 10:12 PM
I'll pick you up at 0500 and we'll go looking.

The address as listed on Teh Zed is correct, I'll be waiting. Bring tacos.

K9CCH
07-19-2013, 11:00 PM
Well we just plumb SAILED right past the exit for "huh?", now we're just at "Whisky Tango Foxtrot?"

y'all just please don't leave me here alone. I may not find my way home.

NA4BH
07-19-2013, 11:11 PM
http://www.youtube.com/watch?v=VT-SFgkVlno

Yeah, the dude on the white Strat, I taught him everything he knows.

K7SGJ
07-20-2013, 09:19 AM
http://www.youtube.com/watch?v=VT-SFgkVlno

Yeah, the dude on the white Strat, I taught him everything he knows.

And he still doesn't know a damn thing. :stickpoke:

W7XF
07-21-2013, 07:40 PM
Well we just plumb SAILED right past the exit for "huh?", now we're just at "Whisky Tango Foxtrot?"

y'all just please don't leave me here alone. I may not find my way home.

Hello.

I won't leave you here alone.
We might not want you to find your way home.
But you're on your own if you venture out towards San Antonio.
Beware of pink Bell 47 helicopters equipped with APU's. They may be piloted by Cowthiefs.

And I'll pass on the tacos.

K7SGJ
07-21-2013, 09:01 PM
Hello

K9CCH
07-21-2013, 11:58 PM
Hello


http://www.youtube.com/watch?v=b_ILDFp5DGA

kb2vxa
07-22-2013, 05:43 PM
Seen over San Antonio yesterday, wave... hello?

NQ6U
07-22-2013, 06:13 PM
Were they doing an air drop of tacos?

K7SGJ
07-22-2013, 08:51 PM
Were they doing an air drop of tacos?

Bedouin tacos.

NQ6U
07-22-2013, 09:43 PM
Bedouin tacos.

No carnitas allowed.

K9CCH
07-22-2013, 10:04 PM
So this is post #30.

There were 4 actual technical posts, which leaves 26 posts of random madness.

I'm thinking there are a few of us who need one of these:

10162

Make sure you take it with food.

10163

NQ6U
07-22-2013, 10:16 PM
So this is post #30.

There were 4 actual technical posts, which leaves 26 posts of random madness.


http://www.youtube.com/watch?v=eIxw42kyyts

K7SGJ
07-22-2013, 10:52 PM
So this is post #30.

There were 4 actual technical posts, which leaves 26 posts of random madness.

I'm thinking there are a few of us who need one of these:

10162

Make sure you take it with food.

10163


Damn. Those four posts almost sent this thread out of control. Fortunately, some of us more "seasoned" hams were able to redirect it to it's proper hijack status. No, no, don't thank us. It's all in a days work.

K9CCH
07-22-2013, 11:09 PM
Damn. Those four posts almost sent this thread out of control. Fortunately, some of us more "seasoned" hams were able to redirect it to it's proper hijack status. No, no, don't thank us. It's all in a days work.


It's why I love this place.

NQ6U
07-23-2013, 12:02 AM
It's why I love this place.

Island style, man.

http://upload.wikimedia.org/wikipedia/commons/4/42/Gesture_raised_fist_with_thumb_and_pinky_lifted.jp g

K9CCH
07-24-2013, 03:00 PM
Ok, so back to the J Pole.

i went to Radio Shack to exchange the 259 connector for a type N connector, but they didn't have one. So because I'm impatient I kept the 259, and bought the male part to put on the end of the coax.

i also picked up some solid copper wire to connect the 259 to the short part of the j Pole. Except its 8g and not 12 so it doesn't fit into the 259 connector. My plan is to file down the end to get it to fit, and then solder around it. I hope that works.

For weatherproofing its going to be electrical tape and silicone. If figure if I can get this one to work, I'll buy all new stuff later and redo it properly, and turn this into a shorter 70cm j pole.

NQ6U
07-24-2013, 03:31 PM
Works for me. An N-type connector is better but the SO-259 will work fine. Have you checked out if the PL-259 fits your coax yet? There are a metric shit-ton of different bushings that screw into the rear part of the PL-259 to fit various cable diameters.

K9CCH
07-24-2013, 03:55 PM
There are a metric shit-ton of different bushings that screw into the rear part of the PL-259 to fit various cable diameters.


No. Great.

kb2vxa
07-25-2013, 02:49 PM
Uh uh, if you use the CATV coax it won't fit into a PL-259 since by itself it takes 1/2" coax and has two bushings, one for RG-58 and one for RG-59. That means leaving the connectors alone and using the appropriate adapter, and a little more tape to cover the whole shebang. You mean to tell me you couldn't dig up a small snippet of 12ga wire? Oh dear, and I thought MY Frankenstein abortions were prize winning creations... oooooohhhh NNNOOOooooooooo. At this point I'd rather try to give the wolf man a haircut.

K9CCH
07-25-2013, 03:13 PM
I'm probably just going to go to Houston Amateur Radio Supply and pick up some LMR-400 with connectors already on it. I talked to my neighbor and he said I should go check them out. He believes they sell short lengths with connectors already installed. We'll see.

W7XF
07-25-2013, 03:44 PM
Chris....IIRC, the RG-8X bushings SHOULD fit RG59 and RG6. Might be worth a try...and you should be able to get those at CellPhone Shack or Frys ... hell, truckstops are good sources for emergency PL-259s, and even emergency coax supplies!!

kb2vxa
07-25-2013, 04:52 PM
I'd check things out before jumping into the fire. While the 8X ferrule may be right for RG-6 it will be too small for RG-6 quad shield which requires a larger F connector to accommodate slightly larger OD. Don't forget whatever connector you end up using it must be crimp on, you cannot solder to aluminium without melting the dielectric. Down there in the armpit you'd probably be better off going with pre-assembled LMR-600 or 800 if you can afford it. I've not only come to the conclusion that using existing cable is confusing the hell out of you but everyone jumps on LMR-400 without realizing it's not a whole heck of a lot better than RG-8A/U (difference is 0.5dB/100' @100MHz).

K9CCH
07-25-2013, 06:49 PM
I've not only come to the conclusion that using existing cable is confusing the hell out of you....


It wasn't confusing until someone through out the bit about the connector size. At that point I realized or rather acknowledged that I don't know enough about what I am doing, and I threw in the towel. I'm just going to go buy some cable, with connectors already on it and be done with it.

I thought that I would just buy some 259 connectors, crimp them onto the end of the coax, screw it all together and hope for the best. But I bought solder type connectors, which wont work with existing coax, and on top of that I don't even know if they would even fit the existing coax. This is one of those projects that sounded fun, and started off cheap. But $5 here, and $10 there, is starting to add up. At this point I'm about $50 into this copper J Pole and I could have just purchased one from http://www.jpole-antenna.com/ for $32.

K7SGJ
07-25-2013, 09:33 PM
It wasn't confusing until someone through out the bit about the connector size. At that point I realized or rather acknowledged that I don't know enough about what I am doing, and I threw in the towel. I'm just going to go buy some cable, with connectors already on it and be done with it.

I thought that I would just buy some 259 connectors, crimp them onto the end of the coax, screw it all together and hope for the best. But I bought solder type connectors, which wont work with existing coax, and on top of that I don't even know if they would even fit the existing coax. This is one of those projects that sounded fun, and started off cheap. But $5 here, and $10 there, is starting to add up. At this point I'm about $50 into this copper J Pole and I could have just purchased one from http://www.jpole-antenna.com/ for $32.

True, but looked at everything you've learned thus far.

WØTKX
07-25-2013, 10:16 PM
Installing connectors is a rite of passage. Required.

K7SGJ
07-25-2013, 10:53 PM
Installing connectors is a rite of passage. Required.


+ 259 Maxwells.

And you must ruin at least one, burn you finger(s), and if you are wearing shorts while soldering, you must drop molten solder on your leg or foot.

K9CCH
07-25-2013, 11:00 PM
I own a soldering iron, and a plumbers torch, and I have a great big glass melting torch too. Trust me, I've burned myself enough. Have you ever had glass rods explode into four THOUSAND pieces and fly at you? TONS of fun!

WØTKX
07-25-2013, 11:09 PM
Years ago, I was working at an automotive/marine audio and two way radio installation outfit. Those little Weller Isotip rechargeable soldering irons had just came out. I was pretty impressed with 'em. Anyhew, I was soldering under the the dash of a really nice boat, laying on my back with my shirt off.

Dropped a huge glob of solder right in my navel. :shock:

That hurt for a few days. :irked:

K9CCH
07-25-2013, 11:10 PM
Years ago, I was working at an automotive/marine audio and two way radio installation outfit. Those little Weller Isotip rechargeable soldering irons had just came out. I was pretty impressed with 'em. Anyhew, I was soldering under the the dash of a really nice boat, laying on my back with my shirt off.

Dropped a huge glob of solder right in my navel. :shock:

That hurt for a few days. :irked:



So that's how you got the third nipple.

K7SGJ
07-25-2013, 11:19 PM
Years ago, I was working at an automotive/marine audio and two way radio installation outfit. Those little Weller Isotip rechargeable soldering irons had just came out. I was pretty impressed with 'em. Anyhew, I was soldering under the the dash of a really nice boat, laying on my back with my shirt off.

Dropped a huge glob of solder right in my navel. :shock:

That hurt for a few days. :irked:

Just reading that, made my innie become an outie. Damn, that had to hurt.

KC2UGV
07-26-2013, 06:06 AM
It wasn't confusing until someone through out the bit about the connector size. At that point I realized or rather acknowledged that I don't know enough about what I am doing, and I threw in the towel. I'm just going to go buy some cable, with connectors already on it and be done with it.

I thought that I would just buy some 259 connectors, crimp them onto the end of the coax, screw it all together and hope for the best. But I bought solder type connectors, which wont work with existing coax, and on top of that I don't even know if they would even fit the existing coax. This is one of those projects that sounded fun, and started off cheap. But $5 here, and $10 there, is starting to add up. At this point I'm about $50 into this copper J Pole and I could have just purchased one from http://www.jpole-antenna.com/ for $32.

And that extra expenditure of $20 bought you knowledge about 75% of hams today don't have. Hell, I've never tried a J Pole antenna, so in that regard, you know more about their construction than I do.

W2NAP
07-26-2013, 10:08 AM
but everyone jumps on LMR-400 without realizing it's not a whole heck of a lot better than RG-8A/U (difference is 0.5dB/100' @100MHz).

any time i hear anyone recommend LMR-xxx I cringe. I guess owning a repeater makes me think in full duplex mode and disimilar metals = duplex grunge.

honestly I recomment heliax for VHF/UHF work.

W3WN
07-26-2013, 11:58 AM
It wasn't confusing until someone through out the bit about the connector size. At that point I realized or rather acknowledged that I don't know enough about what I am doing, and I threw in the towel. I'm just going to go buy some cable, with connectors already on it and be done with it.

I thought that I would just buy some 259 connectors, crimp them onto the end of the coax, screw it all together and hope for the best. But I bought solder type connectors, which wont work with existing coax, and on top of that I don't even know if they would even fit the existing coax. This is one of those projects that sounded fun, and started off cheap. But $5 here, and $10 there, is starting to add up. At this point I'm about $50 into this copper J Pole and I could have just purchased one from http://www.jpole-antenna.com/ for $32.Don't crimp. Solder.

You want a good electrical connection & a good mechanical connection. I've seen too many crimped-on PL-259's come apart under the least bit of stress. The ONLY exception is on some cable I got from N3FB a few years back... but Frank is the CE of one of the local TV stations, and he has the right tools & the experience to do it perfectly. Most of us, with the tools usually at our disposal, well... don't.

KB9VBR has some interesting pictures. Any Copper J-Pole I've seen is usually loaded on the bottom (horizontal segment), and the portable one I have is that way as well. Also, I don't see what shipping costs are... so odds are pretty good that it would be more than $32, when all is said & done. (*)

Besides... now you know how to do it. What price knowledge?


(*)on edit: $9 to $12 for shipping, per antenna

W3WN
07-26-2013, 11:59 AM
any time i hear anyone recommend LMR-xxx I cringe. I guess owning a repeater makes me think in full duplex mode and disimilar metals = duplex grunge.

honestly I recomment heliax for VHF/UHF work.That's interesting.

Several broadcast engineers/hams around here highly recommend the LMR series coax.

W2NAP
07-26-2013, 12:39 PM
That's interesting.

Several broadcast engineers/hams around here highly recommend the LMR series coax.

ive seen to many chunks of LMR where the aluminum foil they use as extra shield has turned into a white powder. i got a piece like that around here somewhere which has suffered that fate.

better off spending the cash and getting heliax. and if you go to hamfests lot of it there for cheap. Ive been told a lot of commercial radio shops will damn near give away heliax.

also look at the loss
@144mhz
LMR-400 1.5db per 100ft
LDF4-50A 0.85db per 100ft.

heliax might be a pain in the ass to work with but damn its good. course on HF RG8 or 213 is fine but heliax sure does well on V/UHF+ well worth the money.

KC2UGV
07-26-2013, 01:06 PM
I suppose I'd have to worry if I were running 100ft+ runs... That's the main reason I just use what is relatively inexpensive. 1db/100ft works out to (My average run) about a total loss of 0.5 db total system loss. It's not even 1/10th of an S.

WØTKX
07-26-2013, 01:12 PM
And LMR-600 is 1.72 db / 100 foot @450Mhz. It's my favorite for general VHF/UHF.

We use it at work for our 900 Mhz RFID antennas, usually 50-70' runs.

This is a very helpful site... http://www.w4rp.com/ref/coax.html

kb2vxa
07-26-2013, 02:09 PM
Too bad Belden discontinued the original 9913, the closest thing to Heliax this side of RG-8. I can see it now, 3" hard line and a J-pole spiraling out of control. Pardon my giggles, transmission lines and grounding are the two most controversial subjects in Amateur Radio, more arguments develop than on the floor of Congress and funnier too. Then there was the time I stripped all the CATV coax off my apartment building, used half of it for transmission line and the other half for grounding the antennas. <razz> Remember, a broadcast engineer has the station's resources at his fingertips, a ham has to be resourceful.

WØTKX
07-26-2013, 02:12 PM
True, 'tis funny. Which is why I threw down with the 'ol balanced line boondoggle. ;)

http://www.jaggedallianceflashback.com/wp-content/uploads/HamsterMeme.jpg

K9CCH
08-02-2013, 04:56 PM
Ok don't laugh at my soldering job... But this is where I'm at. Next up I'm going to put the connectors on the coax and hopefully meet up with my neighbor to tune the jpole. I've flattened out two more clamps to hold them in place, wherever that may fall. I'll solder them once I find out which spot has the least SWR.

K9CCH
08-02-2013, 04:57 PM
Wait... That's night right is it? Dammit.

K9CCH
08-02-2013, 05:01 PM
Well, maybe it is...

K7SGJ
08-02-2013, 07:19 PM
Well, if it all turns to shit, you can always use it to re-plumb the house.

KC2UGV
08-02-2013, 07:21 PM
The electrical tape will do a fine job holding it up on the mast :rofl:

NQ6U
08-02-2013, 07:35 PM
The electrical tape will do a fine job holding it up on the mast :rofl:

My 70cm antenna was held up with nothing more than than a pair of zip ties for several years.

K9CCH
08-02-2013, 08:02 PM
I meant the way the SO-239 connector was soldered on. The wire actually isn't touching the long part of the antenna. Is that correct?

K7SGJ
08-02-2013, 08:06 PM
My 70cm antenna was held up with nothing more than than a pair of zip ties for several years.

So were my pants.

KC2UGV
08-02-2013, 10:00 PM
I meant the way the SO-239 connector was soldered on. The wire actually isn't touching the long part of the antenna. Is that correct?

Yes, the lead should come off at a 90 deg angle to the antenna, for a foot or so.

kb2vxa
08-02-2013, 10:05 PM
"The wire actually isn't touching the long part of the antenna. Is that correct?"

That would cause a short and just as important is making a strong mechanical connection between the connector and the pipe, solder alone doesn't pass muster. In other words solder makes a good electrical connection but is physically weak. Another thing to consider is pressure testing the soldered joints for leaks, if signal leaks out before reaching the radiator the ERP will be a negative value.

K9CCH
08-02-2013, 10:43 PM
So the way I have it is correct then? Am I understanding correctly?

NQ6U
08-02-2013, 10:51 PM
So the way I have it is correct then? Am I understanding correctly?

Looks right to me.

K9CCH
08-02-2013, 10:53 PM
Ok, as for support, I'm going to zip tie a couple of coils to the bottom part to take the strain off of the connector.

KC2UGV
08-02-2013, 10:54 PM
So the way I have it is correct then? Am I understanding correctly?

Yes. The feed line isn't perpendicular far enough, but it's good enough for horseshoes, hand grenades, and 2M antennas :)

kb2vxa
08-03-2013, 01:08 PM
Hey wait a minute, I just noticed something. Are we talking with Chris, Mike, or are we being led around by the nose?

NQ6U
08-03-2013, 01:28 PM
Hey wait a minute, I just noticed something. Are we talking with Chris, Mike, or are we being led around by the nose?

I went to that site, he's offering pre-built j-poles at some pretty good prices. Being forced to buy copper pipe at Home Despot prices would make it hard to compete. I also find it interesting that he includes a short piece of PVC pipe for mounting his antennas, which confirms my suspicion that j-poles don't like being mounted on conductive masts.

K9CCH
08-03-2013, 02:17 PM
I went to that site, he's offering pre-built j-poles at some pretty good prices. Being forced to buy copper pipe at Home Despot prices would make it hard to compete. I also find it interesting that he includes a short piece of PVC pipe for mounting his antennas, which confirms my suspicion that j-poles don't like being mounted on conductive masts.


Yeah. For $32 you can't beat it. I'm in this one for about $50 already. Now that I've paid for the experience, I'll buy his next time.

K9CCH
08-03-2013, 03:53 PM
So this is where I am now. I mounted it to a 5' wooden shovel handle, attached the coax, and now I just need to strap it to the old satellite dish mast on the roof, and run the coax through the existing hole through the wall.

it looks like shit, I have no SWR meter, so I'll just have to connect it and see if we sink or float. I placed the connections at 3.75" above the cross piece as suggested by the plans I used.

W7XF
08-03-2013, 04:34 PM
I'll have to look into those pre-made J-poles... cuz I'm needing to get something up on 6 metres...and NOT a Hamstick!!!!

KC2UGV
08-03-2013, 09:29 PM
So this is where I am now. I mounted it to a 5' wooden shovel handle, attached the coax, and now I just need to strap it to the old satellite dish mast on the roof, and run the coax through the existing hole through the wall.

it looks like shit, I have no SWR meter, so I'll just have to connect it and see if we sink or float. I placed the connections at 3.75" above the cross piece as suggested by the plans I used.

Prior to antenna building, an antenna analyzer is a required tool. Adding to this, you picked on of the hardest antennas to build, to start out with. Try a 1/4 2M ground plane, which has a little bit of gain on 70cm too. Much easier to build (Less fussy). Or, an HF antenna (Even less fussy).

kb2vxa
08-03-2013, 10:54 PM
NOW we get some honest pictures. (;->) Now we get beyond the limitations of those pre-made antennas, soldering to the tubing does not allow for fine tuning adjustment, movable clamps does. While dimensions of the antenna proper determine the resonant point, the larger the diameter the greater the bandwidth up to the point of diminishing returns. Distance from the bottom of the U determines feed point impedance so sliding the clamps up and down you'll find the sweet spot. Now go get an SWR meter, the most basic and essential instrument for doing ANY antenna work, DIY or just tuning up something you bought.

Just two minor changes will do you good, cut off about 2/3 of that tubing below the U and make a couple of 70cM J-poles out of it, maybe one for 1.25M. You're a couple turns short on that choke balun, 5 is about right.
"Now that I've paid for the experience, I'll buy his next time."
And waste all that copper? BTW it doesn't look like shit, it looks like accomplishment.

"I'll have to look into those pre-made J-poles..."
Unless it's FM and repeaters only you want, don't bother. Above 30MHz only mobiles use FM and vertical polarization so on 6M you're limited to a small segment on the top of the band. Weak signal work (mostly CW, SSB and AM when the band is wide open) is where it's at so you'll need a horizontal antenna. If it's omnidirectional you want a delta loop or halo is the way to go BUT being essentially bent dipoles they exhibit negative dBd gain. The way around that is stacking, two bays return the gain factor to slightly above unity and it goes up from there.

K9CCH
08-03-2013, 11:20 PM
Just two minor changes will do you good, cut off about 2/3 of that tubing below the U and make a couple of 70cM J-poles out of it, .



If I don't cut off the excess below the "U", will it inhibit the performance any?

kb2vxa
08-04-2013, 07:59 PM
No, what is below the U is not electrically part of the antenna, just for support. Still it's wasted when it can be used to build another antenna, you only need enough to connect to the main support. Here it comes, don't say it, you'll leave it there. Just don't come crying to me when the first strong wind bends it over and you can't make another J-pole with bent tubing.

There's something spooky about a large Black woman with 7 pin tube sockets stuck to her forehead.

K9CCH
08-04-2013, 08:05 PM
Lol. It's inside laying across the guest bed right now. I still haven't gotten it on the roof. But I'll cut the extra off before it goes up, and add a few extra coils to the balun.

K9CCH
08-07-2013, 05:20 PM
Well it's up there. I took the old dish off the mast and stuck the antenna down in it. Only problem is that it's not exactly straight up and down. The mast is quite a hit larger than the wooden pole, so I'm going to have to come up with something else? Any suggestions?

The coax will be run directly through the existing hole in the wall just below and to the left of the window.

i also cut off the excess copper pipe from the bottom and added two kre turns to the balun for a total of five.

NQ6U
08-07-2013, 05:45 PM
Cut three wedge-shaped wooden shims to stick down into the pipe, then adjust them until the wooden pole is vertical. Otherwise, it's fine. It should last for a few years as is unless a hurricane hits Houston.

K9CCH
08-07-2013, 05:56 PM
Well if a hurricane hits Houston, the last thing I'm worried about is that $50 piece of pipe! LOL

K9CCH
08-07-2013, 08:03 PM
The shims worked. Now I just need a radio to connect it to.

W3WN
08-07-2013, 08:24 PM
The shims worked. Now I just need a radio to connect it to.You can find a used 25 W 2 meter only rig in the $30 - 35 range these days.

K9CCH
08-07-2013, 09:12 PM
You can find a used 25 W 2 meter only rig in the $30 - 35 range these days.


My FTM-350AR will be here on Monday!

kb2vxa
08-08-2013, 12:39 AM
Looks like you're all set and ready to go! Well, assuming you have something to power it with.