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View Full Version : Any9ne know if this antenna mod would work? 40/20m dipole



W5BRM
10-13-2014, 08:55 AM
I have a 40m hamstick dipole using a MFJ-347 as the center support. I'm wondering if it's feasible to hang a 20m inverted V using the hamstick mounts while the hamsticks are still mounted to it, making it a 20/40m dipole. I currently have the 40m hung as a vertical. I am wondering if keeping it as a vertical would affect the 20m inverted v in any way? How/will would they interact with each other in a negative way?

I have a bunch of 16g coated wire and I just need to solder a couple ring terminators to the ends and attach those to the screw in points on the hamsticks and raise it back up. OR I could just remove the hamstick dipoles and make it a monoband. Just need to get a few 3/8 x 24inch bolts.

Anyone have any advice on this?

Thanks

n2nkw

NQ6U
10-13-2014, 09:09 AM
I can't see why it would be any different than any other fan dipole but, before you transmit, I'd put an antenna analyzer on it before you transmit just to be sure that your SWR is in the ballpark. PA transistors don't come cheap.

K7SGJ
10-13-2014, 09:20 AM
I can't see why it would be any different than any other fan dipole but, before you transmit, I'd put an antenna analyzer on it before you transmit just to be sure that your SWR is in the ballpark. PA transistors don't come cheap.


PA transistors are a lot like buses, they don't come, they arrive.

W5BRM
10-13-2014, 09:22 AM
Not a problem there. Got a mfj259c i use to tune the hamsticks. I'm just wondering if it will work ok with the hamsticks in a mostly vertical orientation. The bottom hamstick would be dropping down between the 20m legs and I dont know if that would affect them or not. Gonna try this out this afternoon once the rain quits

NQ6U
10-13-2014, 09:28 AM
You still have your roof, I assume?

K7SGJ
10-13-2014, 09:30 AM
Not a problem there. Got a mfj259c i use to tune the hamsticks. I'm just wondering if it will work ok with the hamsticks in a mostly vertical orientation. The bottom hamstick would be dropping down between the 20m legs and I dont know if that would affect them or not. Gonna try this out this afternoon once the rain quits

I'm wondering if the 20 meter legs might act as a ground plane of sorts, and actually enhance the 40m signal somewhat. As Carl said, it shouldn't act a lot different than a multi-band fan dipole. At least as far as impedance goes. But I would think the angle of radiation would be effected. It would be interesting to model the thing on one of the antenna programs. I suspect, as with most antennas, you may also have to do some pruning for optimum performance. Let us know how it works out. It's an interesting concept.

K7SGJ
10-13-2014, 09:30 AM
You still have your roof, I assume?

Yes, but it's in the back yard now.

NQ6U
10-13-2014, 09:32 AM
Yes, but it's in the back yard now.

That's much more convenient than if it had been in the neighbor's back yard.

W5BRM
10-13-2014, 09:45 AM
heheh yep still got my roof. Was listening to the news this morning. The "roof" that was blown off in town here last night was actually just a screen door...LOL Seems whoever reported it was embellishing a bit or something...

That would be nice if the 20m affects the directivity of my 40m. I seem to only get ne/sw signals. I don't get a lot of florida or washington state sigs. but I get a lot of new england and socal.. I think thats because my "vertical" isn't exactly vertical. It has a 10/15 degree list to is as the coax and pvc pipe i run for the coax to keep it 90 degrees from the dipole leg pulls it off center

KG4NEL
10-13-2014, 10:00 AM
PA transistors are a lot like buses, they don't come, they arrive.

Sounds like an ex of mine...


heheh yep still got my roof. Was listening to the news this morning. The "roof" that was blown off in town here last night was actually just a screen door...LOL Seems whoever reported it was embellishing a bit or something...

That would be nice if the 20m affects the directivity of my 40m. I seem to only get ne/sw signals. I don't get a lot of florida or washington state sigs. but I get a lot of new england and socal.. I think thats because my "vertical" isn't exactly vertical. It has a 10/15 degree list to is as the coax and pvc pipe i run for the coax to keep it 90 degrees from the dipole leg pulls it off center

Vertically-polarized stuff is interesting. For a while in 2011 I was using a vertical dipole with ten-foot horizontal sections on the top and bottom, fed with 300-ohm line in the middle. Let the tuna take care of the rest.

I have no idea what the pattern was, but it was pretty good into Europe.

W5BRM
10-13-2014, 10:10 AM
Vertically-polarized stuff is interesting. For a while in 2011 I was using a vertical dipole with ten-foot horizontal sections on the top and bottom, fed with 300-ohm line in the middle. Let the tuna take care of the rest.

I have no idea what the pattern was, but it was pretty good into Europe.

I don't have a tuner that I'm using at this time. Thats one of my next purchases. I'm surprised my hamsticks are working as well as they are. I have the tip of the top element at about 35ft and the 50 ohm coax feed point about 28ft. I get a good share of europe but not much else. I dont know if thats just the way 40m has been running or if it's a symptom of my sorta vertical orientation. I listened on 30m over a couple days and I saw a whole bunch of Asia, Australia, south Africa and india on jt65. Stuff I just DONT see on 40m

WØTKX
10-13-2014, 10:20 AM
Just hook it up, check it with the analyzer, and try it for a while.
Should work pretty well, you'll probably need to retune a bit.

If the 20m legs are true horizontal, likely to be less interaction.

EzNEC modelling might give you some clues.
But I wouldn't fuss with that. Just do it.

28' feed point on 20 is a bit of a cloud warmer, but it will radiate, eh?

W5BRM
10-13-2014, 10:25 AM
Just hook it up, check it with the analyzer, and try it for a while.
Should work pretty well, you'll probably need to retune a bit.

If the 20m legs are true horizontal, likely to be less interaction.

EzNEC modelling might give you some clues.
But I wouldn't fuss with that. Just do it.

28' feed point on 20 is a bit of a cloud warmer, but it will radiate, eh?

The 20m elements will be Inverted V. The 40m hamsticks are vertical. I have no horizontal elements. I might just take the 40m off and just swap them out as needed if I can't get them to play well together

KG4NEL
10-13-2014, 02:40 PM
I don't have a tuner that I'm using at this time. Thats one of my next purchases.

A decent tuna with a 1:1 current balun (don't skimp on this, whether DIY or commercial) will open up a ton of 'tenna options. Or make you supremely lazy about VSWR.

:)

W5BRM
10-13-2014, 03:10 PM
Can a 1 to 1 cuurent balun b used with the mfj mount im using? Its already got a connector for pl259 coax ends on it

K7SGJ
10-13-2014, 03:16 PM
Usually most 1:1 baluns have an input for a PL259, and output to a set of closed screw eyes (I'm sure they are available with SO239s on each end). But if you are building one, not difficult or expensive, you can use whatever you want for gozintos, and comezouttas.

KG4NEL
10-13-2014, 03:36 PM
Can a 1 to 1 cuurent balun b used with the mfj mount im using? Its already got a connector for pl259 coax ends on it

The big advantage with the balun + tuner idea is that it allows you to use open-wire or twinlead, which is critical for reducing line losses in really-horribly unmatched antennas. Just because the tuner is presenting a nice match to the radio, doesn't mean you aren't heating the feedline instead of the ether.

I was sort of yakking about a situation not entirely applicable here, because your best bet with this current setup is to do exactly what you're doing. Although if it were me I'd probably investigate what you could do with wires alone :)

Who knows, with enough of a horizontal section on each end you might be able to get on eighty, and talk about important things like conspiracy theories and hemorrhoids. Or hemorrhoid conspiracies.

W5BRM
10-13-2014, 04:20 PM
I'm wondering if a Dirty Choke balun would work? I need more coax for that as I only have just one 50ft section and it's not long enough to make a winding and still reach my antenna. Would that have the same effect as a 1:1 current balun?

kb2vxa
10-14-2014, 09:03 AM
"...it's not long enough to make a winding and still reach my antenna."
That's what a double SO-239 "barrel connector" is for and don't forget the cheap black electrical tape to waterproof all outdoor connections. We're HAMS, we experiment, so find your best option and don't forget our motto "whatever works is the answer".

W5BRM
10-14-2014, 09:47 AM
lol I only got just the one stretch of coax. I was planning on getting more then i went out of work on medical. I got no $$$ to get more coax so I'm stuck as to what I can do without cannabalizing other stuff. I'm just gonna have to run without a balun for a while and hope for the best. I'm gonna work on the 20m dipole today if I can get motivated enough. It's frickin COLD outside...lol

kb2vxa
10-14-2014, 01:04 PM
No problema Sr. Just put up the inverted V and be done with it for now, you can always improve on it later. You're complaining of a little cold? Cold weather is antenna weather, just put on some clothes and hop to it before it gets so cold your neighbors will wonder what a Smurf is doing up there and why it isn't moving.

W5BRM
10-14-2014, 04:26 PM
Dipole install in progress. Putting it up as monobander quarter wave inverted v for 20m. Gonna tune ut up. Tmw will readd the 40m hamsticks and see if/how much they interact with each other and retune as needed.

W5BRM
10-14-2014, 05:27 PM
Hmm something wrong somehwere. Got it at 30ft. Quarter wave inverted V. I made it a bit long as i know I hv to tune it. I cant find any resonance anywhere on this. Closest I get is 2.5 swr R17 and X32 at 13.079 on the mfj259c. Got the legs at about 90 degrees for so should be resonant at r50 and x0 at some point. Unless I got something wrong somewhere? Anyone have an idea what went wrong here? No baluns or any fancy mounting. each leg is about 17ft. My desired frequency is 14.076 which makes each leg 16ft 7inches at a quarter wave. Even at 17ft there should be some point of resonance somewhere shouldn't there?

Any advise would be much appreciated

NQ6U
10-14-2014, 05:43 PM
The length seems about right for a starting point, but are you saying that the two legs of the dipole form a 90° angle? That seems a bit sharp to me, and could adversely affect the impedance. Can you flatten it out at all?

kb2vxa
10-14-2014, 05:45 PM
Wait a minute, an inverted V is a half wave. If you're using bare wire each should be 16ft 6in and if insulated a bit shorter, distributed capacitance slightly lowers its resonant frequency.

On edit:
You posted while I was typing so I missed you saying each leg is 17ft. There's your problem, your calculation is correct, cutting a tad too long and trimming for resonance is the way to start. You should be taking readings AT THE ANTENNA which is the proper way to tune an antenna WITHOUT the transmission line in circuit. Reading through the transmission line includes unexpected variables characteristic of the transmission line which introduces errors when trying to find resonance. (Transmission line is a resonant circuit.) Dig out a short piece of coax jumper to connect the analyzer, take your readings upstairs and just dip the SWR meter to find resonance, that's all you're looking for. That other stuff is for other purposes the analyzer may be used for, unimportant for tuning an antenna.

K7SGJ
10-14-2014, 05:49 PM
Wait a minute, an inverted V is a half wave. If you're using bare wire each should be 16ft 6in and if insulated a bit shorter, distributed capacitance slightly lowers its resonant frequency.

Ding ding ding ding

Actually, I think that's what he posted. 16'7 per leg and it's a little long to adjust.

W5BRM
10-14-2014, 05:56 PM
16.6ft at 14.07mhz is a quarter wave. 234/14.07 = 16.6. I made each leg 16.6ft plus a bit for adjustment. it is insulated 16ga stranded wire. I can't get enough height to get a half wave. Not enough room on my property. Thats why i went with quarter wave. Cant a quarter wave be an inverted v?

kb2vxa
10-15-2014, 11:00 AM
"Cant a quarter wave be an inverted v?"
No, an inverted V is a center fed dipole with the elements bent down at a 45 degree angle and a dipole is 1/2 wave end to end. The formula 468/f in MHz gives the overall length, divide the result by 2 for the length of each 1/4 wave element. Two things are confusing you, the antenna is a half wave, EACH ELEMENT is a quarter wave given by the formula 234/f and that formula is used for calculating the elements of a 1/4 wave ground plane, not a dipole. Keep the two separate to avoid confusion in the future. Es claro a mismo? (Is it clear now?) Like I said, since you're using insulated wire the actual length will be a little shorter because insulation adds distributed capacitance which lowers the resonant frequency.

"I made each leg 16.6ft plus a bit for adjustment."
You did the right thing so put the techie stuff on file for future reference and do your pruning, right now you have plums and one really bad pun. Just remember what I wrote about doing it with the coax out of circuit because it introduces errors in your readings. For what it's worth(less), before that handy dandy analyzer came along we fed the lowest practical power through the coax with the SWR meter up top connected to the antenna with a short bit of coax. The PITA was when the band was crowded everything had to be postponed. I remember living near New York City and hearing an AM test on 75M from Annapolis, Maryland, the lowest power at which I could copy the voice message was 25uW ERP. That's not a typo my friend, that's 25 MICROWATTS effective radiated power.

One last thing, while a dipole has a figure 8 pattern broadside, oddly enough for techie reasons beyond the scope of this discussion an inverted V is nearly omnidirectional. Like your 40M loaded vertical dipole, waves will propagate where they will go independent of antenna orientation.

W5BRM
10-15-2014, 11:46 AM
Ah OK. Thanks. I understand now. Thats what I thought. So I got it right. mostly...lol I gotta prune it again. I just don't have an external SWR meter so I either use the internal one in the radio or I use the analyzer. I'll check that this afternoon with my analyzer at the feed point plus a 6 ft of rg8x. Thanks for setting me straight.

WØTKX
10-15-2014, 01:32 PM
Six feet away may be a little close, move the analyzer around physically and watch the readings change.

kb2vxa
10-15-2014, 01:53 PM
6 ft should be OK according to my long broken slide rule so just dip and prune until the dip occurs at the frequency you want. Don't expect a 1:1 match, that only happens with a pure resistive (dummy) load, all you're looking for is a minimum SWR reading indicating resonance. Speaking of dipping meters, I miss the old boat anchors heavy enough to give you a hernia, glowing tubes and plenty of KNOBS to play with. 12V is for wimps, real radios can KILL you.

"Thanks for setting me straight."
I was going to crack another one but that pun stank so bad I can't stand it myself. Hey, let us know how it works out under actual operating conditions, I sure put enough work into it. (;->)

K7SGJ
10-15-2014, 02:02 PM
6 ft should be OK according to my long broken slide rule so just dip and prune until the dip occurs at the frequency you want. Don't expect a 1:1 match, that only happens with a pure resistive (dummy) load, all you're looking for is a minimum SWR reading indicating resonance. Speaking of dipping meters, I miss the old boat anchors heavy enough to give you a hernia, glowing tubes and plenty of KNOBS to play with. 12V is for wimps, real radios can KILL you.

"Thanks for setting me straight."
I was going to crack another one but that pun stank so bad I can't stand it myself. Hey, let us know how it works out under actual operating conditions, I sure put enough work into it. (;->)

You have a slide rule longer than six feet? No shit? Who Gnu?

PA5COR
10-15-2014, 04:07 PM
My FT 2000-D has a P.A. running at 50 volts D.C
10 amps as well ;)
Might kill you too ( if it drops on your head from 20 feet high...

kb2vxa
10-16-2014, 12:03 AM
"You have a slide rule longer than six feet?"
At 352ft and 300lbs it's a bit difficult to use but accurate as hell.

Arc welders run 50VDC @ 250A, so with one as a PSU and a few more output modules you could get about 10KW out of it Class E.

K7SGJ
10-16-2014, 12:52 AM
"You have a slide rule longer than six feet?"
At 352ft and 300lbs it's a bit difficult to use but accurate as hell.

Arc welders run 50VDC @ 250A, so with one as a PSU and a few more output modules you could get about 10KW out of it Class E.

Imagine, welding on a new muffler and calling CQ all at the same time.

K0RGR
10-19-2014, 06:42 PM
This is basically a 'fan' dipole, but only for two bands. The 40 meter elements will load down the 20 meter ones, and vice versa, making them both seem longer than they should be. One key to making this work will be if the Hamsticks can still be tuned to the 40 meter frequency desired. I suspect you will need to prune the antenna carefully. Be certain that both sides are as equal as possible - that will affect the impedance. If the wires are 90 degrees from each other, that may be too narrow a 'V' to work. Start by tuning the 40 meter elements.

Oh, and X=0 might not happen where the SWR is lowest, but that does show where the resonant point is. What is 'R' at X=0?

KC2UGV
10-20-2014, 06:33 AM
The only problem I could foresee is that the hamsticks are not true dipole elements, but loaded dipole elements. So, you might get some unusual interaction between the hamsticks and the wire.

But, nothing some tuning of the wire wouldn't fix. Just make sure you do test it with the analyzer first, as others have said.

kb2vxa
10-20-2014, 11:40 AM
You haven't seen the good DX night thread. He gave up, cut it down to a 17M dipole and it looks like the topic has switched to that thread.

W5BRM
10-20-2014, 11:52 AM
lol yeah talk about derailing my own content... I am SOOO disorganized it just aint funny! I gave up on trying to get it to run as a dual band setup. Couldn't get the 20m dipole to work. so yes I cut it down to 17m. Tried making a new 20m dipole. Still can't get it to resonate even as a monoband inverted V. I'm stumped. Also having the psame problem with 15m as well. I'm at a loss.

KG4NEL
10-21-2014, 10:43 AM
17 is a fun band, anyway.

W5BRM
10-21-2014, 04:27 PM
Just tried making a 40m quarterwave dipole. same thing. no match. I shortened it 5% and still absolutly no match. No swr dips across the band. Its almost as if the antenna isn't there except I got the usual s7 neighborhood noise and can hear a few BC and ssb stations. I ran all day today on 17m with no issues so I don't think its my coax or mount. I am totally stumped on this... i mean really competely and totally stumped. I am at the end of my rope. I can't figure out what else to check.

WØTKX
10-21-2014, 05:10 PM
I (we) still are confused with your description. A dipole is normally considered a half wave.

W5BRM
10-21-2014, 05:26 PM
Well I asked that earlier and didnt get an answer so i tried making a quarter wave. So I guess thats not gonna work. OK I got that part down. I don't have enough horizontal or vertical height to make a 40m halfwave dipole then so that idea is out. Now one thing I DID notice is that there is a close resonance at 14.7 20m so that puts me back in the same boat I was in before making a 20m dipole. The math puts them only 3 inches apart. 196 inches for 40m vs 199 inches for 20m dipole. I'll give it a shot tmomrrow to see if I can get this one to match on 20. It was 2.5 at 14.7mhz at its lowest dip according to the mfj259. I ran into the same thing when I was making the first 20m dipole that didnt work. Maybe I can figure this one out

WØTKX
10-21-2014, 05:36 PM
http://www.westmountainradio.com/antenna_calculator.php

http://www.hamuniverse.com/dipivcal.html

kb2vxa
10-22-2014, 07:52 AM
"I don't have enough horizontal or vertical height to make a 40m halfwave dipole then so that idea is out."

Horizontal height? Oh man, you sure ARE disorganized! (;->) But who said a dipole has to be straight? I knew a guy with a postage stamp lot and a 160M dipole in the back yard, looked like a copper spider on LSD had at it but it worked. When I lived in West Creek, Phil K2PG had a 160M sloping V in his back yard with the far ends running down two small sections of tower to the ground, it didn't work. Using two small trees for end support I bent the ends toward each other about ten feet apart, sort of a sloping open delta, then it worked. BTW with a tuner and open wire ladder line it worked well from 160 to 10 including WARC and Army MARS.

Now get out your copper spider and since there hasn't been LSD since Owsley took off into the stratosphere give it a few drops of whiskey and tell it to get busy.

W5BRM
10-25-2014, 02:34 PM
Ok I think my issue has to be my feedline. I put up the 10m dipole last night. Worked fine. Had a 1.3swr at 28.076. Had 1.6 at 28.500 Raised it to 30 ft from 20 ft. Worked Australia and a few stateside stations before conditions went away. Turned radio on this morning. Worked France and England and some local stuff.

Without making a single adjustment to the antenna.. in fact not even going outside, the SWR just went through the roof about 2 hours after my 1st transmit.

Once again, there is only a minor dip from 27.500 to 29.000 via mfj259. This was reflected accurately via the radio swr meter... except for below 28.0. Radio wont xmit there. SWR read 2.9 from 28.0 to 29.0.

Inspected the connections. All tight. Coax screwed in tight. antenna lengths are still in adjustment. No visible breaks anywhere. No kinks in the antenna wire. There is absolutly nothing wrong with the wire or how its hung. that pretty much leaves just the feedline.

Once I get back to work (hopefully this Monday) I will see about getting a new stretch of coax. Don't have any baluns or anything else so ladderline or balanced line isn't possible at this time. I just don't understand why the coax will work on some bands and not others if it is indeed broken somewhere inside.

I'm also looking at the MFJ window passthrough for coax and balanced feedline but thats gonna be a bit down the road.

Anyway, I'm done for the weekend and longer if I do get back to work. If I don't get back to work, then i'm sunk as I don't have $$$ for a new stretch of coax.

It sucks being poor on medical leave...lol

W7XF
10-26-2014, 11:38 AM
A decent tuna with a 1:1 current balun (don't skimp on this, whether DIY or commercial) will open up a ton of 'tenna options. Or make you supremely lazy about VSWR.

:)

Yellowtail, skipjack, or bluefin???

kb2vxa
10-27-2014, 10:31 AM
Why does every one of your antenna projects end in disaster? Antennas are one of my specialties (more or less) but frankly I've run out of ideas. I'd like to invite you over for a cold 807 but I live in mortal fear of you. (;->)

K7SGJ
10-27-2014, 10:48 AM
One thing I noticed in a photo that was posted, was a wad of the shield just kind of hanging out of the PL259. If that is the way it was done, that is a sure fire place to have an intermittent connection. When it is not making a good electrical connection between the connector and the shield, you are losing one half of your dipole/vee. As RF passes, heat will be generated and can further cause the connection to come and go. If it were me, I would redo the coax connections at each connector insuring proper electrical connection. There are a number of helpful sites on the internet demonstrating the best way to connectorize the coax. I think this would be the first thing to do eliminate the coax/connector situation as a source of trouble.

W5BRM
10-27-2014, 11:02 AM
Why does every one of your antenna projects end in disaster? Antennas are one of my specialties (more or less) but frankly I've run out of ideas. I'd like to invite you over for a cold 807 but I live in mortal fear of you. (;->)

Lol the 12 and 17m turned out fine so not ALL of them were disasters. The 10m i dont know what happened. It changed by itself with no interaction from me. As i said i then i think its the coax. Gonna hv to redo the coax connector. Been planning on that anyway. If i get back to work ( which i doubt... In dr office as i type this) i plan on getting new preassembled coax. My solder skills suck.

W5BRM
10-27-2014, 11:05 AM
One thing I noticed in a photo that was posted, was a wad of the shield just kind of hanging out of the PL259. If that is the way it was done, that is a sure fire place to have an intermittent connection. When it is not making a good electrical connection between the connector and the shield, you are losing one half of your dipole/vee. As RF passes, heat will be generated and can further cause the connection to come and go. If it were me, I would redo the coax connections at each connector insuring proper electrical connection. There are a number of helpful sites on the internet demonstrating the best way to connectorize the coax. I think this would be the first thing to do eliminate the coax/connector situation as a source of trouble.

When i soldered the coax, also soldered the connector to the braid s i know i got a good connection. Still its a sloppy job so itll get redone sometime

KG4NEL
10-27-2014, 02:31 PM
Lol the 12 and 17m turned out fine so not ALL of them were disasters. The 10m i dont know what happened. It changed by itself with no interaction from me. As i said i then i think its the coax. Gonna hv to redo the coax connector. Been planning on that anyway. If i get back to work ( which i doubt... In dr office as i type this) i plan on getting new preassembled coax. My solder skills suck.

Don't try soldering a PL-259 with a standard iron. Get one of those couple-hundred-watt Weller guns and heat that thing up. If the barrel isn't up to temp, you're going to be pretty frustrated.

KG4NEL
10-27-2014, 02:32 PM
That being said, I typically buy preassembled coax because I'm teh lazy.

WØTKX
10-27-2014, 04:53 PM
Learning to do a good job on antenna connectors is important.
It's not too bad once you get the hang of it.

http://www.k0bg.com/coax.html

kb2vxa
10-28-2014, 05:40 PM
What you need is what works wonders for me, a horse leg mofo 100W Hexacon HD plug tip soldering iron. Anything less is a futile effort, the key is that huge heat sink so the tip doesn't go cold and you have to hold it on the work overheating it or worse, the tip gets stuck to it. If it takes more than one or two seconds to make a perfect solder joint you're using the wrong tool or just plain doing it wrong. Hint: a small dab of paste or drop of liquid ROSIN flux put on first speeds things up considerably, don't depend on flux core solder alone. One more, a good coax stripping tool is all important. Not only does the job go fast without damaging the coax but if you don't get the strip lengths just right you're pretty much forked.

http://www.hexaconelectric.com/HOME/tabid/36/Default.aspx

WØTKX
10-28-2014, 06:24 PM
Everybody has slightly different methods. The trick is getting the solder quickly and well on that darn shield. While I have used a large iron that stays hot (guns don't do that) I prefer a butane mini-torch now. Works good for me. :dunno:

K7SGJ
10-28-2014, 06:34 PM
I use an oxy acetylene cutting torch. 12 seconds, and you are done. Actually, well done. And a nice puddle to boot.

kb2vxa
10-29-2014, 12:15 AM
I just discovered something from the previous page: "... i plan on getting new preassembled coax. My solder skills suck." A word of warning, pre-assembled coax has crimp on connectors that with the possible exception of F connectors suck worse than your soldering skills. You'll just have to learn like we all did, fouled everything up along the way and practice makes perfect. Just practice on scraps and junk parts, hold off on serious projects until you're perfect like I am.

K7SGJ
10-29-2014, 10:08 AM
I just discovered something from the previous page: "... i plan on getting new preassembled coax. My solder skills suck." A word of warning, pre-assembled coax has crimp on connectors that with the possible exception of F connectors suck worse than your soldering skills. You'll just have to learn like we all did, fouled everything up along the way and practice makes perfect. Just practice on scraps and junk parts, hold off on serious projects until you're perfect like I am.

I have to disagree about the crimp connectors. Although I do still use solder style PL259s, I also use quality crimp on coax connectors of all kinds. Although much more expensive, I find they are just as reliable as the solder type connectors, and a lot quicker to put on. However, I always solder the center conductor because I've found that to be more stable. I think the secret is using good quality coax as well as good quality connectors. It is also imperative to use the right cable prep and crimp tools. For the occasional user of PL259s, I agree that solder is the way to go. The number of required tools for prep and crimping connectors for all the various styles can get quite pricy; plus due diligence during installation is a must.

I really can't comment on commercially available cable with crimp connectors preinstalled, since I've never used any. But I would think buying them from a reliable company would be satisfactory. And, as always, cheap import crap should always be avoided. I know the cable is usually crap and the connectors can't be much better.

KG4NEL
10-29-2014, 10:16 AM
Crimp BNCs are industry standard. Never had an issue (well, other than the bastids losing their crimpers in the vans at $75/pop).

WØTKX
10-29-2014, 11:45 AM
As are crimp N connectors.

You just need the good stuff.
The crimpers are very expensive.

kb2vxa
10-30-2014, 07:26 AM
So now it's crimp vs. solder? I could make a comment about Radioreference and QRZoo turning me into the grumpy old bastid but I bite my tongue. We're talking AMATEUR Radio here, not professional installers or companies that manufacture cable assemblies where it PAYS to have a toolbox full of expensive strippers and crimp dies because time is money.

Getting back to The Torch, (somebody's old CB handle) I used a propane torch with a soldering tip for outdoors and since I got a little better at it have a pencil torch I took off a crack ho and can of butane in my toolbox. I also have the previously mentioned horse leg iron, an assortment of pencils I picked up here and there and a temperature controlled soldering station so on occasion when I have to solder something I have the right tool for the job.

K7SGJ
10-30-2014, 09:39 AM
So now it's crimp vs. solder? I could make a comment about Radioreference and QRZoo turning me into the grumpy old bastid but I bite my tongue. We're talking AMATEUR Radio here, not professional installers or companies that manufacture cable assemblies where it PAYS to have a toolbox full of expensive strippers and crimp dies because time is money.

Getting back to The Torch, (somebody's old CB handle) I used a propane torch with a soldering tip for outdoors and since I got a little better at it have a pencil torch I took off a crack ho and can of butane in my toolbox. I also have the previously mentioned horse leg iron, an assortment of pencils I picked up here and there and a temperature controlled soldering station so on occasion when I have to solder something I have the right tool for the job.

Crack hos assemble coax assemblies? Who Gnu?

kb2vxa
10-30-2014, 03:51 PM
Anyone who bought Radio Shack coax assemblies, that's who.

K4PIH
11-07-2014, 01:55 PM
You don't want to use Radio Shack connectors. If you use ahot iron the plastic insulator between the center and the body will meltbecause they use recycled plastic from computer cases from Mumbai ... overpriced/dubiousquality. Buy some real connectors from HRO mail order or a local supply store.Like the Pappa John's commercial, better connectors, better soldering, betterRF. You need a good solder connection on the center pin and a good compression sleevepinching the shield to the outer.
As for crimp coax connectors, I leave those to the 18 yearold college students with the COX cable magsign on their Subaru.

N8YX
11-07-2014, 02:43 PM
As for crimp coax connectors, I leave those to the 18 yearold college students with the COX cable magsign on their Subaru.


Problems with Subarus? :chin:

KG4NEL
11-07-2014, 03:07 PM
Are they held together with RG-6 and crimps?

K7SGJ
11-07-2014, 03:09 PM
Problems with Subarus? :chin:


Maybe it's just the 18 year old college students with Cox. :bbh:

KG4NEL
11-07-2014, 03:16 PM
Pfft, what do they know about pinching the compression sleeve at that age.

K4PIH
11-10-2014, 01:57 PM
Coat hangers, lots and lots of coat hangers.