Re: [IRCA] More coax experiments
> Did you know that you can get shielded CAT5 cable? I'd try just regular audio wire such as Belden 8451 or the Grainger equivalent. The twist isn't as tight as CAT5, but should be more than adequate for LW and MW. It can be used with a normal crimp-on RJ-45 plug as well. I have a roll of that around and may try making up a cable. It'd be simple to add a switch off my existing adapter box for a selectable ground. That way I could do an immediate A/B to see what effect the added ground has. A work in progress - but at least there is progress! Craig Healy ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Charlies, I doubt my problem is with bad coax. It is cheapie stuff that is leaky I have discovered. Replacing the matching transformer box with a metal one has made a difference already. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Russ, I will have to make some phone calls and see who had small metal boxes. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Craig Healy wrote: > One other thing I want to try is to roll out some chicken wire over the CAT5 > to see if it shields the wire from pickup. The capacitance to ground, plus > the inherent loss may just help. Maybe just the 50' closest to the truck. > It will be very easy to do an A/B test. Set out the CAT5, do a bandscan > with it terminated. Then roll out 50' of chicken wire over the nearest 50' > and do another bandscan. Compare notes. If it helps, then do another 50'. > It may function just as a series of chokes on the wire itself, using the > lossy ground for attenuation. Chicken wire is cheap, so.. That certainly would be a very interesting test... Did you know that you can get shielded CAT5 cable? You need special RJ-45 connectors for the stuff because they have to have a grounding tab on them, but the stuff is available on reels and can be easily crimped to shielded RJ-45 connectors. At least with balanced line you don't have to worry about chokes on the wire itself, though they still might be needed on the shield of shielded CAT5 or twinax. On unshielded balanced transmission lines it's all about line balance to prevent common mode pickup. (Normal mode for desired signals on a balanced transmission line is differential mode.) Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
> Once that's done, if you needed more isolation, I'd replace the box with > a metal one. If the sleeve-type choke works well enough, use the plastic > box you have. I have been continuing my tests with the CAT5 balanced line. The BNC connector, 1.4:1 toroid transformer, and RJ45 were put in a Hammond 1590G cast aluminum box. Then I connected the box to the truck radio. Tuned through the whole AM band and didn't hear any signal, not even a het with the R30CC in USB mode. Nothing. Next I connected the 150' run of CAT5 to the box and terminated the other end in a 100 ohm resistor on a RJ45 jack, no shielding. Very short leads, however. In tuning through the band, much of it was below the noise floor of the R30CC. Locals were down a significant amount from the whip antenna. Semi-locals like some Boston stations and all NYC clears were non-existent. So, the box did help. Kudos to Rick Kunath for the suggestion. I need to order some more BNC jacks and some of the Hammond boxes to make up some more adapter boxes, and cut another length of CAT5. Next trick is to put the RPA-1 preamp at the antenna end to further swamp out the remaining leakage. I'll just run the preamp off a 12V 7AH lead-acid battery such as is used in a computer UPS. That way no wiring needs to go there to supply the power for the preamp. Looks like progress! Once the DX Engineering phaser comes back next month, I'll try again to phase the two loops. However, I will set them up away from any metallic objects. I think the tower in the yard is warping the loop patterns. One other thing I want to try is to roll out some chicken wire over the CAT5 to see if it shields the wire from pickup. The capacitance to ground, plus the inherent loss may just help. Maybe just the 50' closest to the truck. It will be very easy to do an A/B test. Set out the CAT5, do a bandscan with it terminated. Then roll out 50' of chicken wire over the nearest 50' and do another bandscan. Compare notes. If it helps, then do another 50'. It may function just as a series of chokes on the wire itself, using the lossy ground for attenuation. Chicken wire is cheap, so.. Craig Healy Providence, RI ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick, Methinks you're going to wear your poor coax out from all the testing. I would simply advise disconnecting both ends of the coax and, using a good multimeter, look at the resistance between the center conductor and the shield. It ought to look to be open, ideally. But I wouldn't get upset if I saw may 5,000 ohms or more. Less and I would investigate the coax. When you first bridge the conductors of the coax, you may see a momentary reading on the multimeter. This is normal and is just the multimeter's voltage charging the capaci- tance of the coax. 73 for now, Cholly ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
--- Patrick Martin <[EMAIL PROTECTED]> wrote: > Rick, > > Changing the box is the easiest thing to do.. The coax is under the > house and 12 feet of it buried. I can easily build a new box and > crimp a > new coax fitting on the end of the coax. The plastic boxes are just a > lot easier to get and use. No drilling of holes, etc. The last time I > tried to find a small metal box at Radio Shack, they never had any. These should be readily available from most mail-order or internet suppliers. I'd certainly want to be sure Home Depot had them before I went, as that wouldn't be someplace I'd expect to find those. Russ Edmunds Blue Bell, PA ( 360' ASL ) [15 mi NNW of Philadelphia] 40:08:45N; 75:16:04W, Grid FN20id <[EMAIL PROTECTED]> FM: Yamaha T-80 & Onkyo T-450RDS w/ APS9B @15' AM: Hammarlund HQ-150 & 4' FET air core loop Choose the right car based on your needs. Check out Yahoo! Autos new Car Finder tool. http://autos.yahoo.com/carfinder/ ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
--- Patrick Martin <[EMAIL PROTECTED]> wrote: > Chuck, > > I have some short pieces of orange conduit I have used, but of course > direct burial would be easier. I am going to build a metal box with > the > coax fitting and all and then I will see how much leakage the coax > really has. As Rick pointed out, I have too much open wire. But > again, I > wonder if there will be any changes in pattern? > *** I'm inclined to favor the directions you've stated above as to me the combo of banana plugs and a plastic box are the biggest potential weak points. Then I'd try a choke too before replacing the cable. While the BOG's we deploy at LBI are on sand, and we use fans as terminators rather than ground rods, we run coax for three wires, 2 BOG's and a phase wire, up from the beach which is roughly a 75' run. Most of the coax is RG-8 of one variety or another, and usually a run is comprised of two lengths with a connector. We then run thru splitters to distribute them. There's more than adequate signal, and we haven't noted any significant issues. Owing to the relative short lengths we've used recently, we're considering longer runs this year to ighten the pattern some, but we're limited that way. I don't know how good a comparison this is, and we've never tried seeing how much pickup there might be on the coax ( usually we're strapped for time in getting set up for sunset DX on night 1 ), but that's part of my reasoning for suggesting that the coax might be the least likely of the possible causes. Russ Edmunds Blue Bell, PA ( 360' ASL ) [15 mi NNW of Philadelphia] 40:08:45N; 75:16:04W, Grid FN20id <[EMAIL PROTECTED]> FM: Yamaha T-80 & Onkyo T-450RDS w/ APS9B @15' AM: Hammarlund HQ-150 & 4' FET air core loop Fussy? Opinionated? Impossible to please? Perfect. Join Yahoo!'s user panel and lay it on us. http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7 ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > and then getting a > piece of Quad RG6 and running it out the door to the antenna is easy to > test. I can go right up the band frequency by frequency and check gw > reception and see if there is any difference. Then if there is and my > old coax is that leaky I can then decide which avevue I need to go to > replace it. Right now, I still don't know if it will make any difference > to change all of this. Yep, that's what I'd do. See what you can do with the coax first. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > I fiqure I am going to need the metal box anyway, so why not start > there. It will be interesting to note, if the s meter readings go down > by attaching the cap on the end of the coax anyway. Yes, that will tell the tale. Until you get that (the coax) RF tight, nothing else will matter. > The choke idea > sounds a bit involved, so I would do that as a last resort. The metal > box first, then the coax, To test the coax with the cap to terminate > it, what kind of s meter readings would be exceptable? Anything? I'd say extremely low readings, if any at all. As to chokes, Radio Shack has some ferrite clamp-on chokes available. They have some that open in half and you wind the coax through it, but coax generally can't be bent that tight and the chokes are a ferrite mix that works better at HF. Plus the inter-turn coupling affects the ultimate ability of these to choke at MW. There are some you might try, part number: 273-105. You'd need 3 or 4 of these. You have to modify the plastic holder by cutting off the ends of the holder so that when you place them on the cable, end-to-end, the ferrite touches the next choke in line. With the plastic still on the ends of the holder, the ferrite is too far apart, and you wind up with less choking effect. Ferrite material designed for medium wave is better, but these might be worth a try if you need to see if they'd help. As to the ferrite toroids for choking, these just slide over the coax, and you tape them in place, one touching the next, in a big stack. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, What you are suggesting with hardline is pretty involved, a lot more than I would want to do, unless I had to. . At least at this point. That would be a last resort to go through all of that. I still have no clue if all of this will make any difference in the long run. It may not. Building the metal box is easy if I can find one, and then getting a piece of Quad RG6 and running it out the door to the antenna is easy to test. I can go right up the band frequency by frequency and check gw reception and see if there is any difference. Then if there is and my old coax is that leaky I can then decide which avevue I need to go to replace it. Right now, I still don't know if it will make any difference to change all of this. But the metal box is easy to do. I have some pieces of orange plastic conduit anyway. I have used it, but it is a pain to deal with. The cable company left a piece of it at the neighbors years ago, she tossed it when they never picked it up and I brought it home. It is stiff, but I still have some left. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, Changing the box is the easiest thing to do.. The coax is under the house and 12 feet of it buried. I can easily build a new box and crimp a new coax fitting on the end of the coax. The plastic boxes are just a lot easier to get and use. No drilling of holes, etc. The last time I tried to find a small metal box at Radio Shack, they never had any. They had one like 5 inches by 5 inches as I remember. So living in a rural area we have little choice. I have to go into the Portland area to get to a Home Depot. No biggie, but a roundtrip of 160 miles or so. We will be getting a Home Depot out here 3.5 miles away within a year though. That will help. I fiqure I am going to need the metal box anyway, so why not start there. It will be interesting to note, if the s meter readings go down by attaching the cap on the end of the coax anyway. The choke idea sounds a bit involved, so I would do that as a last resort. The metal box first, then the coax, To test the coax with the cap to terminate it, what kind of s meter readings would be exceptable? Anything? We have no powerhouse stations. We have three 1 KW locals in the county. (KAST-1370-5.9 miles), KKEE-1230-7.1 miles) and KSWB-840-8.9 miles). After I cap the coax, if I am still getting CBU at S9, I do have an issue. hi. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Chuck, I have some short pieces of orange conduit I have used, but of course direct burial would be easier. I am going to build a metal box with the coax fitting and all and then I will see how much leakage the coax really has. As Rick pointed out, I have too much open wire. But again, I wonder if there will be any changes in pattern? 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Chuck Hutton wrote: > For short distances, go to Home Depot and get the (usually) gray plastic > conduit that is used to run outdoor wiring. Then bury your coax without > worrying about it being direct burial or not. Just doing a quick Google on CATV hardline pricing... It looks like .500 PE jacketed and flooded aluminum CATV hardline is going for about $0.65 per foot. (This is cheaper than what questionable quality quad-shield direct burial stuff I've Googled.) It's probably cheaper than burying some PVC pipe and pulling non-flooded cable through it. Without the flooding compound between the jacket and the shield, you can't control condensation and water ingress, and you'll have that in an underground installation as the non-flooded cable breathes with temperature changes. Although with the PVC at least you can fish new cable in at any time without digging up the yard. I'd still pull in flooded cable if you went the PVC pipe route. Flooding compound is a sticky goo that prevents water from getting into the cable even with a jacket cut and prevents water movement. The down side with the CATV hardline is that you need a jacket removal tool, coring tool, and center conductor cleaning tool. (Cable Prep is my favorite brand.) And these are specific to any cable size, so tools for .500 won't work on .750, etc. But once you have them,they last a long time, and aren't expensive. The good thing about .500 cable is that not many CATV systems still use it, so you can pretty well scrounge connectors, splices, adapters, and reuse them and get cut-offs, ends of rolls, and tear outs cheap from your local cable system's cable scrap yard. And since there is only a thin copper coating over the aluminum center conductor of aluminum hardline, the aluminum stuff isn't exactly a hot commodity with copper recyclers yet. Jacketed and flooded aluminum hardline is a lot easier to handle than rolled PVC, but not quite as easy as jointed PVC, though you'll eventually have leaks with jointed PVC as the ground shifts. I think if I were there, I'd want to do a quick test with an antenna-end sleeve-type choke (leaving your plastic box and existing matching transformer as is) and see what happens with the existing cable before I got to doing anything else. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > I thought that is what you would say. hi. A metal box eh? I guess I > should look for one. I have used the plastic set ups since 1988 and I > still have heard a lot of great DX. I wonder going to all of this work > is going to really make any difference in what I hear? I know lab tests > and the like do show a difference, but in the real world will be do > anything? I guess I will try it for the Eastern beverage as I am more > concerned about the directivity of that more than the EWEs. The EWEs > pretty much have the directional pattern they are supposed to have, even > without all of the better coax and a metal box. I can try the Eastern > beverage. If I notice a difference, I can always change the SW EWE set > up. The vertical I don't care much about as I use it mainly for SW. The > WNW EWE has more buried coax and will be harder to change out the coax > there. >Maybe I can find a small metal box at Radio Shack tomorrow. I can > install a coax fitting on the one side and then a couple banana jax on > the other. Then everything will be shielded The banana jax will be > inside the metal box as well as the coax fitting. At least I can check > out the coax better terminating the end with a cap. That way I can tell > how much the coax is leaking. At least it is a start. I think if it were easy, the first thing I'd try would be to replace the coaxial cable with something better shielded and do a receive test to see what happens with what you have. If the coax you already have has marginal shielding, changing the box to a metal one likely won't matter, as there are plenty of places along the run of cable where signals can leak back in. Once the cable has been changed, adding a sleeve-type choke at the antenna end would likely be my next step. This will choke off any currents coming back along the length of the coax from making their way from the outside of the shield and onto the inside of the shield at the antenna end and on their way back down the (now properly shielded new) coax to your receiver. Once that's done, if you needed more isolation, I'd replace the box with a metal one. If the sleeve-type choke works well enough, use the plastic box you have. A sleeve-type choke is a series of ferrite cores, sized to slide snugly over the coaxial cable. These are typically a series of ferrite cores stacked up maybe a foot or more long at medium wave. You need enough cores to get a high impedance to the RF at the frequency of interest. There are commercial chokes available, or you can make up your own with purchased cores (Amidon comes to mind, and they'll help you pick out the right cores), and seal the outside. I usually make these up separate from the actual coax run to the antenna. That way you can remove them and move them around. I put a connector at each end and place them in series with the cable run at the antenna end. Some folks use toroid cores and wind the coax through the core to make a choke. I don't like these as the inter-turn capacity negates some of the isolation effects. But for testing, if you have a core handy, at least you could see what the partial effect would be. If you have a signal generator or some source of RF at medium wave, you can do a pretty good test for cable leakage by just laying it out on the ground straight, applying RF to one end, and a dummy load to the other, and moving a radio with a ferrite rod antenna along the cable to see if yo have any hot spots. You don't need a dummy load of any power handling capacity, as the RF levels for testing like this, or terminating the coax for a receiver-connected leakage test are very low level. You could make yourself up a dummy load just with a metal box with a coax connector and a carbon resistor inside (equal to the cable's characteristic impedance) that would work for testing. But, low cost commercial units made up inside a connector body are pretty cheap, likely cheaper than the parts to make one up. Rick Kunath > Thanks again. > > 73, > > Patrick > > > Patrick Martin > KAVT Reception Manager > > ___ > IRCA mailing list > IRCA@hard-core-dx.com > http://montreal.kotalampi.com/mailman/listinfo/irca > > Opinions expressed in messages on this mailing list are those of the original > contributors and do not necessarily reflect the opinion of the IRCA, its > editors, publishing staff, or officers > > For more information: http://www.ircaonline.org > > To Post a message: irca@hard-core-dx.com > > ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx
Re: [IRCA] More coax experiments
Patrick: For short distances, go to Home Depot and get the (usually) gray plastic conduit that is used to run outdoor wiring. Then bury your coax without worrying about it being direct burial or not. Chuck -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Patrick Martin Sent: Saturday, August 18, 2007 7:39 PM To: Mailing list for the International Radio Club ofAmerica Subject: Re: [IRCA] More coax experiments Rick, Thanks again for the great advice. So most Quad RG6 is not made for burying. That I did not want to hear! Hardline would work, but very expensive and stiff as a board to use. Not fun. It has been years since I delt with any hardline. I wonder if they make Quad RG6 you can bury? I know some RG6 is not made for burying, but the stuff I bought is listed for burying. I have ribbon cable running from my old 8.5 foot dish that has been buried in the ground not for 22 years and still works fine. It is tough as nails. A very hard jacket. I remember back in 1985, the stuff ran about $1 a foot! I don't know how shielded that is, but the two RG6 cables as tough. If I used that stuff, it would probably last a lifetime for MW use, but stiff and hard to bend. As I remember the shield was pretty decent, but it has been years since I looked at it. But it still works well up above 12 GHZ. Yes, the cheapie RG6 I have is the rolled foil, not glued. It just unrolls easily. The braid isn't all that good either. If I replace the cable, my problems will probably be cut down a lot. But again, will it make much difference with the reception on the beverage.? Of course with a test, I could always hook up a 100 foot piece and run it out and switch back and forth and see what difference it really makes. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, I thought that is what you would say. hi. A metal box eh? I guess I should look for one. I have used the plastic set ups since 1988 and I still have heard a lot of great DX. I wonder going to all of this work is going to really make any difference in what I hear? I know lab tests and the like do show a difference, but in the real world will be do anything? I guess I will try it for the Eastern beverage as I am more concerned about the directivity of that more than the EWEs. The EWEs pretty much have the directional pattern they are supposed to have, even without all of the better coax and a metal box. I can try the Eastern beverage. If I notice a difference, I can always change the SW EWE set up. The vertical I don't care much about as I use it mainly for SW. The WNW EWE has more buried coax and will be harder to change out the coax there. Maybe I can find a small metal box at Radio Shack tomorrow. I can install a coax fitting on the one side and then a couple banana jax on the other. Then everything will be shielded The banana jax will be inside the metal box as well as the coax fitting. At least I can check out the coax better terminating the end with a cap. That way I can tell how much the coax is leaking. At least it is a start. Thanks again. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > There might be a difference, but it might be so small not to notice it. > When I get some Quad RG6, I can do an A/B test. I guess I should put a > regular coax fitting on the plastic boxes. It would be easier as the > short wires the banana plugs are on I am sure have pick up. A coax fitting on a plastic box won't do the trick. You'll still have ingress. The box would have to be metal. If you can't do a metal box, try a sleeve-type choke balun in addition to the existing matching transformer. Don't know about direct burial quad. It isn't usually used for that purpose. If we needed that kind of shielding, we'd always bury hardline. Might be some out there though. I don't know what the pricing differential would be of copper quad-shield coax vs. direct burial aluminum small hardline these days. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Steve, I wonder if that is Quad RG6 they have? Direct bury would be a lot better> I would think that there must be some Quad RG6 that you can bury. There must be others that need it buried at times, even if most of it is used for Head end use. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, I have some plastic tubing I have run coax through, so that is an option. Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, I could always use regular Quad RG6 under the house, but the 12 feet buried, I could switch to hardline putting a female fitting on the end under the house. But of course any extra connection there is a chance of a stray signal. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, There might be a difference, but it might be so small not to notice it. When I get some Quad RG6, I can do an A/B test. I guess I should put a regular coax fitting on the plastic boxes. It would be easier as the short wires the banana plugs are on I am sure have pick up. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > So most Quad RG6 is not made for > burying. You could always bury it in a protective tube. I've seen garden hose used. But that's just as big a hassle to install as hardline. Your worry will be jacket failure and water ingress. > Hardline would work, but very > expensive and stiff as a board to use. Not fun. It has been years since > I delt with any hardline. The armored direct-burial aluminum stuff isn't too bad to work with. Especially in smaller diameters (.500 or less) that would be great for medium wave. Likely it's a lot cheaper than Andrew Heliax with a copper shield these days. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: > I'll bet most of the coax that DXers are using is the same grade that I > am using. I wonder what the difference would be if we all switched to > Quad RG6? The answer to that would depend on how much coax-based signal ingress there is on a given installation. If there is ingress pickup in a direction the antenna has a null, then it might make a worthwhile difference. > Would we notice that much of a difference? I am wondering > changing to the Quad RG6, what the Eastern beverage will react like? As > I mentioned earlier, when taking the R8 out to the antenna and running > the beverage directly in, a couple years back during the day, I noticed > nothing different than running it through the coax in the house. The question would be, what was the ingress situation then? Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Don't forget that DX Engineering recommends their 75 ohm F-6 Style Direct Bury coax. They have good things to say about it, and recommend it for all their receiving application products. http://www.dxengineering.com/ Look for the RG-213/RG-8X section on the home page, then click on the link to the 75 ohm cable, where there is more info. They sell the connectors and the crimp tools too. (I have not used any of their 75 ohm coax.) Steve - Original Message - From: "Patrick Martin" <[EMAIL PROTECTED]> To: "Mailing list for the International Radio Club ofAmerica" Sent: Saturday, August 18, 2007 7:38 PM Subject: Re: [IRCA] More coax experiments > Rick, > > Thanks again for the great advice. So most Quad RG6 is not made for > burying. That I did not want to hear! Hardline would work, but very > expensive and stiff as a board to use. Not fun. It has been years since > I delt with any hardline. > I wonder if they make Quad RG6 you can bury? I know some RG6 is not made > for burying, but the stuff I bought is listed for burying. I have ribbon > cable running from my old 8.5 foot dish that has been buried in the > ground not for 22 years and still works fine. It is tough as nails. A > very hard jacket. I remember back in 1985, the stuff ran about $1 a > foot! I don't know how shielded that is, but the two RG6 cables as > tough. If I used that stuff, it would probably last a lifetime for MW > use, but stiff and hard to bend. As I remember the shield was pretty > decent, but it has been years since I looked at it. But it still works > well up above 12 GHZ. > Yes, the cheapie RG6 I have is the rolled foil, not glued. It just > unrolls easily. The braid isn't all that good either. If I replace the > cable, my problems will probably be cut down a lot. But again, will it > make much difference with the reception on the beverage.? Of course with > a test, I could always hook up a 100 foot piece and run it out and > switch back and forth and see what difference it really makes. > > 73, > > Patrick > > Patrick Martin > KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, I'll bet most of the coax that DXers are using is the same grade that I am using. I wonder what the difference would be if we all switched to Quad RG6? Would we notice that much of a difference? I am wondering changing to the Quad RG6, what the Eastern beverage will react like? As I mentioned earlier, when taking the R8 out to the antenna and running the beverage directly in, a couple years back during the day, I noticed nothing different than running it through the coax in the house. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Rick, Thanks again for the great advice. So most Quad RG6 is not made for burying. That I did not want to hear! Hardline would work, but very expensive and stiff as a board to use. Not fun. It has been years since I delt with any hardline. I wonder if they make Quad RG6 you can bury? I know some RG6 is not made for burying, but the stuff I bought is listed for burying. I have ribbon cable running from my old 8.5 foot dish that has been buried in the ground not for 22 years and still works fine. It is tough as nails. A very hard jacket. I remember back in 1985, the stuff ran about $1 a foot! I don't know how shielded that is, but the two RG6 cables as tough. If I used that stuff, it would probably last a lifetime for MW use, but stiff and hard to bend. As I remember the shield was pretty decent, but it has been years since I looked at it. But it still works well up above 12 GHZ. Yes, the cheapie RG6 I have is the rolled foil, not glued. It just unrolls easily. The braid isn't all that good either. If I replace the cable, my problems will probably be cut down a lot. But again, will it make much difference with the reception on the beverage.? Of course with a test, I could always hook up a 100 foot piece and run it out and switch back and forth and see what difference it really makes. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick Martin wrote: >I would think if the center connector of good coax had quad shield, > you should hardly get any signal with the braid grounded. Keep in mind that there are really three conductive surfaces on any piece of single-shield coaxial cable. One is the outer surface of the center conductor. The other two are the inner and outer surfaces respectively of the shield. The inner and outer surface of the shield are two separate conductors as far as high frequency RF is concerned. As long as there is sufficient shield coverage, there will be negligible leakage of the signals on the outside of the shield into the inner surface of the shield and into the receiver. Virtually none with hardline. This separation of surfaces between the inner and outer surface of coaxial cable can be compromised by poor or improper connectors, poorly installed connectors, poorly shielded receivers, poorly shielded terminations at the antenna (though this last can be improved using common-mode choking on the coaxial cable at the antenna end. > I think the > RG6 I have is cheapie stuff. It is RG6 that can be buried, but in > looking at it, the braid is not 100%. That's the first thing you'll notice about cheap coax. > There is foil, but I have no idea > how good it all is. The foil is likely not bonded to the dielectric. Take a piece apart and see if it (the foil seam) can be opened up, sort of along a folded over joint in the foil. If so, it's junk. The shield allows ingress and egress along the joint and the joint opens up even wider making things worse with handling and bending, also temperature variation. (I want to use stronger terms for the poor quality of cable manufactured like this, but can't on a family list.) There is good RG-6 available, including direct burial cable. This would have 98% tinned shield coverage, a foil shield bonded to a polyfoam dielectric, copper plated steel center conductor, as well as flooding compound between the jacket and the shield braid, all surrounded by an abrasion resistant insulating jacket. > So going to quad shield will probably solve my > problems. If I had to bet on it, I'd think so. Do keep in mind that most quad-shield coaxial cable is designed as head end cable and is not going to last long outdoors buried. You might want to keep this in mind when you look at cable types. The other thing is that quad-shield cable does not use standard connectors. You'll want to get the proper cable prep cutting tool, and need a supply of the proper crimp on connectors, along with the proper crimping tool. If you attempt to use what tools you have for your RG-6, you are wasting your time and cash on the quad-shield cable. As I described above, you *have* to have the connectors installed on the cable correctly to get the isolation you want between the inner surface of the shield and the outer surface of the shield. Without that isolation you have your current situation of strong ingress via common-mode currents, and the ingress will happen again. > should not be getting CBU at S9! Correct. Rick Kunath ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Chuck, Is the source there in Aberdeen, set up so they run a storefront to buy off the street? Aberdeen is 1.5 hours from me and if we come up to Grayland, that would work out fine. I would think if the center connector of good coax had quad shield, you should hardly get any signal with the braid grounded. I think the RG6 I have is cheapie stuff. It is RG6 that can be buried, but in looking at it, the braid is not 100%. There is foil, but I have no idea how good it all is. So going to quad shield will probably solve my problems. I should not be getting CBU at S9! OK on the ground rod. In reality I have 14 feet in the ground. The 4 foot Radio Shack and the new 10 foot copper. I presume if I put in another 10 foot pipe, I should space it about 8 feet away. I hope the ground is that soft 8 feet away. hi. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
I wouldn't assume 1 pipe is good enough. The soil in your area has as low a conductivity as any place in the US. If you still have problems, a second ground pipe will cut the grounding resistance in half so is a worthwhile effort. One of the cheaper places for quad shield is the ebay dealer in Aberdeen WA that always has coax for sale. Perhaps you or one of the Grayland guys could pick some up next month as I'm sure one of us will be out there. Chuck -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Patrick Martin Sent: Saturday, August 18, 2007 9:38 AM To: Mailing list for the International Radio Club ofAmerica Subject: Re: [IRCA] More coax experiments Chuck, I just installed a new 10 foot copper pipe for the receiver ground a few days back. So that should be enough. I probably will have to mail for Quad Shield RG6 as I doubt any of it is available on the coast. For the record, the local cable company (Charter) has leaky cable. For cable we have Fred Meyer & Radio SHack. Patrick ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Chuck, I just installed a new 10 foot copper pipe for the receiver ground a few days back. So that should be enough. I probably will have to mail for Quad Shield RG6 as I doubt any of it is available on the coast. For the record, the local cable company (Charter) has leaky cable. For cable we have Fred Meyer & Radio SHack. Patrick ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
Re: [IRCA] More coax experiments
Patrick: Cable systems need very good shielding to prevent over-the-air signals and noise from getting into the cable system. Because of that, you can easily and cheaply buy quad shielded RG6. It should have no leakage through the shield. That doesn't mean the problem is totally solved. You should also install a choke balun and a good receiver ground. That makes sure that anything on the shield (it's an antenna too) has an easy path to ground and a difficult path towards your receiver. Probably a better coax will notably improve your coax leakage. Chances are somewhat in your favor the choke balun isn't necessary. Chuck -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Patrick Martin Sent: Friday, August 17, 2007 9:27 PM To: irca@hard-core-dx.com; [EMAIL PROTECTED] Subject: [IRCA] More coax experiments I went back out tonight after tuning in KFI 640 and I could hear something u/KFI off the Eastern beverage. I tried the test again with grounding the far end of the coax at the matching transformer. KFI got weaker and the station(s) behind KFI were more there. I am beginning to really feel that the coax indeed is affecting the directional pattern of the antennas. But what to do about it.? I can run anything under the house, but the last 6-8 feet has to be buried, so open wire probably is not an option. I yes I could run coax and ground the shield every few feet. That might help, but it is alot of extra work. I wonder if there is coax out there that has no extra pickup? It must be the shielding. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
[IRCA] More coax experiments
I went back out tonight after tuning in KFI 640 and I could hear something u/KFI off the Eastern beverage. I tried the test again with grounding the far end of the coax at the matching transformer. KFI got weaker and the station(s) behind KFI were more there. I am beginning to really feel that the coax indeed is affecting the directional pattern of the antennas. But what to do about it.? I can run anything under the house, but the last 6-8 feet has to be buried, so open wire probably is not an option. I yes I could run coax and ground the shield every few feet. That might help, but it is alot of extra work. I wonder if there is coax out there that has no extra pickup? It must be the shielding. 73, Patrick Patrick Martin KAVT Reception Manager ___ IRCA mailing list IRCA@hard-core-dx.com http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: irca@hard-core-dx.com
