| Index | Thread | Archive | Jul-2001 | Archive | Send |
 |
  |
|
   |
|
  |
|
You are right, in some respects it is a real crap shoot and gamble. I have a C36XR here at home and so far it has been very reliable, both electrically and mechanically. By the way I have a C3E mounted at 50' with a home made mount. THe tower is some sort of commercial one that I built piece by piece. It is 36" on a side..so it does not allow much turning, but the lower C3E will go from 275 deg to 30, which covers JA and EU nicely..That ant. replaced an old A4s..interestingly when I first listened to the C3E it was so quiet I thought it was not working..but it really plays at 50'. I compare it with a T-8 log on another tower at 50'. But no comparison with the A4s, much superior IMO. I look at the way the C3E is put together and then the KLM 2 ele 40, and it seemed reasonable the C3E would have less problems,and the 11 feet difference in height,I didn't think would be that significant. The 40 is servicable where it is and the C3E would be a problem, either getting the crane again or taking out rotor etc and lowering. I had such great luck with the crane in not bending and busting up elements,I think I wouuld do that again. It cost $270 for the crane and I thought safety wise and antenna wise, that was a good investment in time and money. Good luck and hope to see you in a contest.. I don't operate from that qth as much as here at home, but a few times a year get to the cabin to do a contest. Will look for you.. 73 Ken At 11:20 AM 7/12/01 -0400, you wrote: >It sounds like you really did your homework. I guess I was fortunate enough to >purchase a mast that was 1 foot longer (21 feet) but that's a story, I mean ordeal >for another conversation. The 40m beam mods turned out very well, I'm very happy >the way things worked out. While the mods did add about 10 lbs to the antenna at >least most of the element droop is now gone. I have had the antenna up for about >two years now with no real problems, its really appears robust. Here in New >England we can get some nasty ice storms so it was important when I first decided >to put up a large antenna like this that I do everything possible to ensure its >survivability, hence the mods. With the "interesting" feed system on the C19XR I >wanted to make sure I had easy access to it in just in case I needed to service >it. So as you know it really is a crap shoot with the type of stacking >arrangement that we both have. Anyway you look at it one antenna is very >difficult to service. > >The only other beam on the tower right now is a 10-4CD at 30 feet (fixed EU). I >am in the process though of installing a 15-3CD at 55 feet (fixed at EU) and a >WX0B swinging gate sidemount and rotor for the 10m beam. I hoping I will be able >to rotate it from EU through to the South Pacific. If I get time before CQWW >PHONE I like to install a 160m Inv.-L using the tower as one of the supports. Its >nice to talk someone else with the same stacking arrangement. Maybe well meet in >one of the DX contests or a pileup sometime. > >73, > >Les > > > >Ken Eigsti wrote: > >> GM Les, >> RE: Stacking 40 and C3E... >> >> Thanks for the reply.. >> >> I guess my main reasoning for putting the tribander on top was because my >> rotor plate is about 9 feet down in the tower (commercial type tower with >> no adjustment of rotor plate at this point in time). The mast was 20 feet >> which left approx. 11' above the tower. I wanted to get 12 feet separation >> but couldn't. I figured if the 40 were on top and with the "droop" in the >> 40 meter elements this would effectively shorten the distance between the 2 >> antennas..In my mind the interaction would be a bigger factor than the >> extra 11 feet for the 40 mtr beam..The 40 has been at this height (85') for >> several years and has played very well. It is located at 9,000' above sea >> level and the land slopes at about a 12% grade to the north/northeast. >> >> Also, I have had problems with loose hardware/connections etc. with the 40 >> mtr beam and have had to take it down in the past..(1 element at a time). >> My gamble was that the Force 12 will be more reliable and will require less >> maintenance.. >> If the C3E at 95' goes south I have a log periodic (T-8) at 50' and a C3E >> at 50'. If the 40 goes south there is no back up. Due to the location in >> the trees and in the mountains of Colorado, a crane isn't always accessible >> for repair. This played somewhat into my thinking too. >> >> In September W0DC and W0BV and myself will give it a real workout with CQWW >> RTTY. This location is not actually my home qth, but a rental cabin that I >> rent to hams..soon to have a website going with info on the rental etc. >> >> Those were the factors that played into my reasoning..right or wrong.. HI. >> >> 73 Ken W0LSD >> >> At 09:00 AM 7/12/01 -0400, you wrote: >> >I found your report on your stacking of a C3E and 40m beam very >> interesting. I >> >have a C19XR at 80 feet with a modified (W6QHS) Cushcraft 40-2CD 12 feet >> above >> >it. both antennas play extremely well and the SWR on each is as advertised. >> >Prior to installation I did a lot of research and found 12 feet to be the >> >minimum stacking distance in order to avoid interaction. Many people >> >recommended that if a 12 foot separation wasn't practical to turn one antenna >> >90 degrees. >> > >> >I'm a little curious why you decided to stack the 40m beam under the C3E >> rather >> >then above it. It would seem to me that you would want to elevate your >> lowest >> >frequency beam as high as possible. >> > >> >If you want to take a look at my array check it out on my webpage at >> >http://www.tiac.net/users/lpeters/www/antennas.htm . >> > >> >Les Peters, N1SV >> > >> >Ken Eigsti wrote: >> > >> >> Hi, >> >> >> >> Thought I would follow up with results with C3E stacked above a Ele KLM 40 >> >> meter beam as several of you were interested.. >> >> >> >> If you remember, I first posted wondering if C3E initial SWR measurements >> >> on the SAW HORSE were to be worrisome..I had nominal SWR on 10 and 20 but >> >> high on 15. (5:1) >> >> 50% of the responses said just make sure dimensions are correct and put it >> >> up, and 50% said point vertical or get it up in the air. I didn't have the >> >> ability to get it up in the air (trees all around tower) so just went up >> >> with the rechecked measurements. (which were correct) >> >> >> >> Here are the results: >> >> >> >> Plan was to put C3E on top of a KLM 2 ele 40 mtr beam, with spacing to be >> >> 10 feet. At 95' on top of the 40 @ 85', again the 10 and 20 were 1.2 to 1.5 >> >> as advertised but the 15 meter portion was still high, 3:1 at CW end and >> >> lowest was 2.2:1 on 21.300. ALSO the signal reports from DX on the C3E at >> >> 95' were 2-3 S units less than a C3E that was at 50' fixed on EU on the >> >> same tower, consistantly. >> >> >> >> Solution: >> >> >> >> I rotated the 40 meter beam 90 degrees and the SWR on 15 dropped from 3:1 >> >> on CW to 1.5 and 2.2:1 to 1.3 on SSB. Also, the gain appeared to come back >> >> with equal or better signal reports with DX Vs. the C3E at 50 feet. I have >> >> noticed the propagation plays a huge role in the signal reports, but the >> >> SWR improved greatly, and a majority of the time the top C3E is >> >> stronger..especailly at opening and clsoing of bands, which is the "way it >> >> is suppose to be". >> >> >> >> Moral of the story: >> >> >> >> Even though 10 feet would seem to be enough spacing (KLM 40 mtr beam and >> >> C3E) by rotating the antennas 90 deg. appears to have made all the >> >> difference in the world, with both SWR on 15 and gain.. All this time 40 >> >> appeared to not be affected with either gain or SWR..this from signal >> >> reports and measured SWR. Rotating did not affect 10 or 20. >> >> >> >> If you have a similar antenna system, you might want to plan on rotating >> >> the antennas 90 deg to each other.. >> >> >> >> 73, >> >> Ken W0LSD >> >> >> >> -------------------------------------------- >> >> Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. >> >> Force 12 Web site: http://www.qth.com/force12 >> >> >> >> Submissions: send to Force12Talk@qth.com >> >> To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com >> >> Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk >> >> For problems with the list, contact n4zr@qth.com >> > >> >Attachment Converted: "c:\eudora\attach\les.peters.vcf" >> > >> >> -------------------------------------------- >> Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. >> Force 12 Web site: http://www.qth.com/force12 >> >> Submissions: send to Force12Talk@qth.com >> To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com >> Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk >> For problems with the list, contact n4zr@qth.com > >Attachment Converted: "c:\eudora\attach\les.peters1.vcf" > -------------------------------------------- Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. Force 12 Web site: http://www.qth.com/force12 Submissions: send to Force12Talk@qth.com To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk For problems with the list, contact n4zr@qth.com |
This Thread
|
This Author (Jul-2001)
|