Home |
Search |
Today's Posts |
#11
|
|||
|
|||
Looking For Ideas & Recommendations
It's a new hole -- two days old now though. I am using an MFJ-1623
tuner which also includes tuning for the counterpoise ground which I'll be using. The wire will be enough to hold one small bird -- if necessary I can always rebuild with heavier wire (the MKII version I mentioned before)! I checked carefully before I drilled and missed the glass entirely which is unusual because Murphy lives with me! I've never seen him, but his influence is always around! The magnetic loop would not be using the window frame -- I have some 1/2 inch flexible copper tubing which I brought from my condo (which will officially be off my books at noon today!) Last week we had a flea market in Calgary. Having given away all my precious ham radio parts (aka junk) I was in dire need of a roller inductor and a variable capacitor or two to build (if necessary) an artificial ground, or a matching device of some sort for whatever purpose I might dream up. I walked into the market, paid my admission, and the first thing I saw was a box (about 4 cu ft) of variable caps of assorted shapes and sizes. I bent down to have a closer look since I could hardly believe my eyes, and asked the seller 'How Much?' At the same time, I noticed another box of the same size full of assorted inductors, some roller inductors, some coil forms, some coil stock and such. It was like a dream come true. The seller responded '20 bucks for the whole box' and I asked 'How about 20 bucks for both boxes' and he accepted! Talk about a lucky find -- some of that stuff is hard to find nowadays, and to purchase would cost a fortune. I have both boxes in the trunk of my car as there is little room in my suite to allow me to start collecting parts aka junk! I've brought the cream of the crop up to my suite and have cleaned them off using an electric toothbrush and a mildly abrasive cleaner -- they look like new. I now have sufficient L and C, both fixed and variable, or every sort and description to keep me happy for a long while. The rest I will store in my brother's garage until the next flea market where I intend to recoup my $20 bucks plus the admission price! I've tested the MFJ-1623 and it will work 80 thru 10M with the wire -- the wire is basically the same as the 12 foot whip only longer but thinner. If it doesn't, I have another MFJ-949E which I got as junk because the coil switch was burned (I replaced it in an hour with a new single pole 12 position) and it's been tested and used by a friend of mine for the last couple years. If one or the other works or doesn't, I've got all that LC stuff from the flea market so if necessary I can put together enough to load a wet noodle. I did load a wet noodle once, and worked from Penhold AB to Red Deer AB (about 10 miles) just to show it could be done! I love antennas. Does anyone recall reading a book on antennas that had a Chapter subtitle saying 'Antennas are Funny People!'? I'd love to find the book again. My carpeting is wall to wall, so the chicken wire ground would have to be on top of the carpet. I'm sure though, that if anyone asked, I would simply explain 'I'm a Ham' and they would shake their heads understandingly and not ask any more foolish questions! One way or the other, with the planned setup, I intend to get some signals out -- come hell or high water. I don't give up on my hobby after all these years, and I've helped many a ham get on the air under worse (but not much worse) circumstances. Gotta get downstairs and vote -- we are having our provincial election today! 73 Irv VE6BP "Jeff Liebermann" wrote in message ... On Sun, 22 Apr 2012 23:18:17 -0600, "Irv Finkleman" wrote: I just want something quick and cheap so I've ruled out anything like copper clad steel and such. Will your 25ft span of copper wire support a few birds? If not, please reconsider copperweld. Just to clear things up on the geometry, the wire will run out the window horizontally to the tree (about 25 ft) and then drop vertically (another 25 ft approx) through the tree to just above the ground. Sort of an inverted letter "L". It is just a random wire, and the best I can do at the moment given my current situation. Do you have an antenna tuner? The FT-817ND does not have a built in antenna tuner. You're going to need one with your random wire and random configuration. The hole through the window frame is too small (1/4 in.) for conduit but I plan to use a heavy plastic kids drinking straw, tilted down on the outside, and plugged with some silicon seal at each end where the wire enters and exits. Ummm... is this an existing hole are you going to drill a new hole? The modern windows that I've seen have the glass extend almost to the edge of the frame with only a sheet rubber spacer in between. You're highly likely to drill through the glass if you decide to drill the frame. I may even try loading the window frame (aluminum, 5 ft x 5 ft (approx)) using a handy sheet metal screw for the connection. With 5 watts, that might work. Forget about building a magnetically coupled loop. You would need to split the frame at some point, and install a variable capacitor. That's probably not going to happen. If your window proves to be uncoated glass (unlikely), you might consider two squares of aluminum foil on both sides of the window to couple through the RF via a ladder line. You won't get much capacitance so it won't work on the lower frequencies, but should be tolerable for the higher bands. A reminder -- the ground system will be tuned counterpoise wires running along the wall inside my apartment. I have an MFJ-1623 tuner which will handle tuning the antenna and the counterpoise in a very nice compact arrangement with only one meter to watch! Good, you have a tuner. However, that's designed specifically to handle a 12ft balcony mount HF antenna. I don't know what it will do with a longer antenna. Looking at the schematic: http://www.mfjenterprises.com/pdffiles/MFJ-1623.pdf it seems to be a crude L match, which isn't going to match every combination of reactance and frequency. The meter does NOT indicate VSWR, so you really won't know if the tuner is effective. My guess(tm) is you're going to purchasing a more elaborate antenna tuner, a VSWR meter, or using a 12ft piece of wire. I once used a large sheet of WELDED chicken wire under the carpet for a "ground". It has to be welded to prevent the galvanizing from forming diodes. It sorta worked but nobody wanted the lumpy carpet. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#12
|
|||
|
|||
Looking For Ideas & Recommendations
Thanks for taking the time to help me out. "Edwin Johnson" wrote in message ... Hello Irv, On 2012-04-23, Irv Finkleman wrote: 1. Is there wire with camoflage insulation? (just kidding!) I plan on using wire with beige or tan colored insulation. I I do a fair amount of camping with portable operations and have an 80m loop and end-fed zepp at the house in a residential area with no restrictions. Actually, the black or copper wire (when it starts turning from shiny) is the less visible of all, either against sky or trees. My ef zepp is white with blue stripes and it actually glistens at certain light angles. You actually have to look to find the loop in the yard and it is 294 ft long, made of #16 gauge copper clad. This first antenna here is going to be quick and simple with Tan colored wire. If that doesn't work, the MKII may incorporate your suggestion! a 1/4 inch hole in the aluminum window frame. I was going to feed it through a plastic straw to prevent chafing and possible short circuiting. Any suggestions on the best way through the hole to prevent any problems? With a 1/4 inch hole, actually might be less, you could run a very short piece (a few inches/cm) of r8x, r59, r58, or any of the smaller coax and simply trim off the shield at the end and use the middle conductor for the wire. Also, small rubber, teflon, or plastic tubing such as used in model airplanes might work. I considered the coax feed through but would prefer it all be one piece of wire from the tuner to the end. Thanks for the suggestion though. I use parallel pieces of coax with shields soldered together and connect my open wire feed to the center conductors to get under my metal framed window. Actually have a strip of wood with holes for this and close the window down on that strip of wood. Of course in the winter up in AB you have to be more careful with cold air than we do in Louisiana. hi When I had my house, I had so many holes drilled in my basement window that the frame looked like a strainer. I ran open wire and used the same arrangement for my open wire feeder -- I've always liked open wire -- it permitted so much more than a coax fed antenna system. Thanks again for your assistance! Will listen for you on the air. Good luck. 73 ...Edwin, KD5ZLB Irv VE6BP __________________________________________________ __________ "Once you have flown, you will walk the earth with your eyes turned skyward, for there you have been, there you long to return."-da Vinci http://bellsouthpwp2.net/e/d/edwinljohnson |
#13
|
|||
|
|||
Looking For Ideas & Recommendations
On Mon, 23 Apr 2012 09:20:58 -0600, "Irv Finkleman"
wrote: The wire will be enough to hold one small bird -- if necessary Attach a spring to the end of the wire. That will take up the slack and help absorb the impact of the bird when landing on the wire. If you don't mind reinstalling the wire occasionally, attach a thin sewing thread on the end of the wire. When the bird lands, the thread will break, not the wire. I checked carefully before I drilled and missed the glass entirely which is unusual because Murphy lives with me! I've never seen him, but his influence is always around! You were lucky. Try not to rely on luck. I've tested the MFJ-1623 and it will work 80 thru 10M with the wire -- the wire is basically the same as the 12 foot whip only longer but thinner. Yep. I would expect it to work with the 12ft antenna it was designed for. However, you were suggesting a 50ft long antenna (with a tree in the middle), which might not work. If it doesn't, I have another MFJ-949E http://www.mfjenterprises.com/Product.php?productid=MFJ-949E That's much better. My carpeting is wall to wall, so the chicken wire ground would have to be on top of the carpet. I've snuck flat CAT5 cable under wall to wall carpet for wiring a LAN (for internet connectivity). A steel wire snake, a carpet kicker, and an assistant, was all that was needed. Could could do the same with thin copper wire and never see a lump. I'm sure though, that if anyone asked, I would simply explain 'I'm a Ham' and they would shake their heads understandingly and not ask any more foolish questions! Hint: It's much easier to ruin your reputation than it is to improve it. Methinks it best to look and act normal for a few weeks, and then surprise the neighbors, than to do the reverse. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#14
|
|||
|
|||
Looking For Ideas & Recommendations
On 4/22/2012 5:29 PM, Irv Finkleman wrote:
1. Is there wire with camoflage insulation? (just kidding!) I plan on using wire with beige or tan colored insulation. I think sky blue or grey would provide the wrong contract. Any ideas on this? 2. The far end of the antenna will be hanging from and in the branches of a tree. I will only be running 5W (if I'm lucky) and wonder about the voltage at the end of the wire. Will some heat shrink provide suitable insulation to prevent corona from starting the bush on fire? Is there a better idea? I will be using PTFE (Teflon) insulated wire. 3. I'll be running the wire from inside my suite through a 1/4 inch hole in the aluminum window frame. I was going to feed it through a plastic straw to prevent chafing and possible short circuiting. Any suggestions on the best way through the hole to prevent any problems? 4. Is there a way to tell if the glass in my windows has some property that greatly attenuates signals? I'd ask the management but I don't want to trigger them into realization that future QRM will probably be emanating from my 'shack'! I plan to work the world while remaining invisible to those around me. If asked, I'll just explain that the wire is an antenna for my short wave receiver!!!! This is the first time I've had to use a store bought rig! Until now I've either had modified surplus or burned out rigs which I rebuilt. I've always been an advocate of low power, but real QRP is new to me too -- and I equate it to the difference between dynamiting ponds and fly fishing! Time will tell! :-) When I became ill I gave away all my 50+ years accumulation of valuable ham radio equipment, tools, test equipment, and books -- collectively A.K.A. "Junk". It's fun starting from scratch -- at least my shack is not a terrible mess -- YET! Do folks still mail QSL cards? Or can I settle for emailing a graphic equivalent of my own design? I've been off the air for a couple years now and think that things may have changed while I was out of the picture. This is not a big problem as printing and using the local buro shouldn't be too much of a problem. The hundreds of rare QSL's coming into my mailbox my invite unanticipated curiosity from the management. Thanks in advance for any ideas you may have. This is the first time I've run through a metal window frame or dropped the wire into and among the branches of a tree. 73 Irv VE6BP Calgary, AB Just a hair away from being on the air again! Calgary, is that right? Do you need to allow for snow, ice and wind in designing your antenna? I have had good luck while camping, with transparent fishing line at the end of antenna wire. It has some stretch, is easy to tie to tree limbs, etc. And a spool will last forever. Unless you have other ideas for the window hole, put the wire through and use a hot glue gun to seal the hole. If you can reach both sides of the hole, do the same on the outside. RTV also works. Good luck. Paul, KD7HB |
#15
|
|||
|
|||
Looking For Ideas & Recommendations
Thanks Paul,
I never thought of it, but some monofilament (I'm a sport fisherman) will fill the bill. Until now I've always used parachute cord but don't have any anymore. I plan on sealing the hole at both ends with RTV. Hopefully the wire I use will stand up to the harsh Alberta winters, all my antennas have so far, but if need be I can readily replace the wire with very little effort. According to my calculations, which include Murphy's Laws, the antenna should stay up until minus 40 degrees, a windstorm, and blowing snow occurs -- and according to Murphy it will all happen in the middle of a QSO with some extremely rare DX! Personally, I have always found Murphy to have been somewhat of an optimist! Thanks again for the suggestion, Irv VE6BP "Paul Drahn" wrote in message ... On 4/22/2012 5:29 PM, Irv Finkleman wrote: 1. Is there wire with camoflage insulation? (just kidding!) I plan on using wire with beige or tan colored insulation. I think sky blue or grey would provide the wrong contract. Any ideas on this? 2. The far end of the antenna will be hanging from and in the branches of a tree. I will only be running 5W (if I'm lucky) and wonder about the voltage at the end of the wire. Will some heat shrink provide suitable insulation to prevent corona from starting the bush on fire? Is there a better idea? I will be using PTFE (Teflon) insulated wire. 3. I'll be running the wire from inside my suite through a 1/4 inch hole in the aluminum window frame. I was going to feed it through a plastic straw to prevent chafing and possible short circuiting. Any suggestions on the best way through the hole to prevent any problems? 4. Is there a way to tell if the glass in my windows has some property that greatly attenuates signals? I'd ask the management but I don't want to trigger them into realization that future QRM will probably be emanating from my 'shack'! I plan to work the world while remaining invisible to those around me. If asked, I'll just explain that the wire is an antenna for my short wave receiver!!!! This is the first time I've had to use a store bought rig! Until now I've either had modified surplus or burned out rigs which I rebuilt. I've always been an advocate of low power, but real QRP is new to me too -- and I equate it to the difference between dynamiting ponds and fly fishing! Time will tell! :-) When I became ill I gave away all my 50+ years accumulation of valuable ham radio equipment, tools, test equipment, and books -- collectively A.K.A. "Junk". It's fun starting from scratch -- at least my shack is not a terrible mess -- YET! Do folks still mail QSL cards? Or can I settle for emailing a graphic equivalent of my own design? I've been off the air for a couple years now and think that things may have changed while I was out of the picture. This is not a big problem as printing and using the local buro shouldn't be too much of a problem. The hundreds of rare QSL's coming into my mailbox my invite unanticipated curiosity from the management. Thanks in advance for any ideas you may have. This is the first time I've run through a metal window frame or dropped the wire into and among the branches of a tree. 73 Irv VE6BP Calgary, AB Just a hair away from being on the air again! Calgary, is that right? Do you need to allow for snow, ice and wind in designing your antenna? I have had good luck while camping, with transparent fishing line at the end of antenna wire. It has some stretch, is easy to tie to tree limbs, etc. And a spool will last forever. Unless you have other ideas for the window hole, put the wire through and use a hot glue gun to seal the hole. If you can reach both sides of the hole, do the same on the outside. RTV also works. Good luck. Paul, KD7HB |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Some ideas ... | Antenna | |||
5/8 over 5/8 over 5/8.. On 2m - Looking for ideas | Antenna | |||
Any ideas of the best value -vs- money for 6 and 2M? | General | |||
Heathkit HW-32A Ideas | Boatanchors | |||
Heathkit HW-32A Ideas | Boatanchors |