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References: [ +from:4cx250b@miamioh.edu: 95 ]

Total 95 documents matching your query.

61. Re: Topband: Ladder line Beverage Installation (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Thu, 13 Apr 2017 12:21:30 -0600
I used porcelain insulators with a lag screw on one end and screwed them into the opposing sides of the 4x4 support posts. I threaded the wd1a through the large hole in the insulators, and adjusted t
/archives//html/Topband/2017-04/msg00025.html (8,545 bytes)

62. Re: Topband: DX Engineering final field test of the 3Y0Z Bouvet 160 meter vertical (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Mon, 28 Aug 2017 14:53:55 -0600
Wow, I want one! Nice job, Tim! Jim w8zr Sent from my iPad _________________ Topband Reflector Archives - http://www.contesting.com/_topband
/archives//html/Topband/2017-08/msg00068.html (7,537 bytes)

63. Re: Topband: Vac relay keying (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Wed, 15 Nov 2017 06:24:55 -0700
Trevor, Its unclear to me what youre looking for. One transistor and a 24V power supply can activate a vacuum relay, but are you trying to key up an amplifier with the relay, ground a receive antenna
/archives//html/Topband/2017-11/msg00085.html (8,951 bytes)

64. Re: Topband: Detuning Relay Flyback Diode (score: 1)
Author: Jim Garland <4cx250b@miamioh.edu>
Date: Sun, 24 Dec 2017 08:40:27 -0700
I'm always hesitant to challenge anything Jim VE7RF says about amps, because he's almost always right, but here I have to respectfully disagree with a couple (not all!) of his points.  I, too, call p
/archives//html/Topband/2017-12/msg00111.html (13,609 bytes)

65. Re: Topband: Supporting Ladder line (score: 1)
Author: "Jim Garland" <4cx250b@miamioh.edu>
Date: Sat, 6 Jan 2018 13:38:14 -0700
Vic, I've had nothing but bad luck in trying to support long horizontal lengths of ladder line. In my case, I have two 720 ft bidirectional beverages, which I initially made of heavy duty commercial
/archives//html/Topband/2018-01/msg00018.html (9,193 bytes)

66. Re: Topband: DX Conditions Last Night (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Mon, 8 Jan 2018 11:30:14 -0500
Roger, You had a solid 569 signal into New Mexico last night, despite frequent static crashes. Wonder what your power and antenna(s) were? Here, I was running 1500W into a 26m vertical (w/top capacit
/archives//html/Topband/2018-01/msg00029.html (7,992 bytes)

67. Re: Topband: OT - US Hams, WWV closure (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Tue, 21 Aug 2018 22:02:50 -0400
I sold my GPS time base and replaced itbwith a $75 surplus rubidium standard I bought on eBay. They're smaller than a paperback book. I had to add a power supply and enclosure, but it works great, ou
/archives//html/Topband/2018-08/msg00106.html (9,518 bytes)

68. Re: Topband: Air wound coil (score: 1)
Author: Jim Garland <4cx250b@miamioh.edu>
Date: Sun, 2 Sep 2018 16:03:32 -0600
On this general topic, I'm erecting a 68 ft aluminum self-supporting pole (DX Engineering) that is four inches OD at the bottom, tapering to about 1/2 inch at the top. It is designed as a full size 1
/archives//html/Topband/2018-09/msg00008.html (8,851 bytes)

69. Re: Topband: Radial wire (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Wed, 5 Sep 2018 08:00:26 -0400
Jeff, I also use THHN 14Awg stranded wire laying flat on the ground. I use brown insulation to match the desert floor, and one or two lawn staples per radial (each is 120 ft long). I'm not certain, b
/archives//html/Topband/2018-09/msg00049.html (9,114 bytes)

70. Re: Topband: Edge-wound inductors vs round stock (was Air Wound Coil) (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Fri, 7 Sep 2018 20:15:25 -0700
Don raises interesting points. A couple of minor addenda. First, keep in mind that "skin depth," iwhich is the tendency of an AC current to flow near a conductor surface, is frequency dependent. The
/archives//html/Topband/2018-09/msg00076.html (12,273 bytes)

71. Re: Topband: 75 meter 1/4 wave vertical on160 (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Sat, 17 Nov 2018 12:46:17 -0500
Hi Doug, I've got exactly the same setup. I use two coils, a 2uH shunt coil, one side of which is grounded, and a 22uH loading coil that connects to the top of the shunt coil at the bottom of the ant
/archives//html/Topband/2018-11/msg00159.html (8,359 bytes)

72. Topband: Observations on a base-loaded 70 ft vertical (score: 1)
Author: "Jim Garland" <4cx250b@miamioh.edu>
Date: Sun, 2 Dec 2018 14:18:07 -0700
Hi All, I have a 70ft 80m self-supporting vertical, which I've baseloaded to bring it down to 160m. The antenna is about 800 ft. from my shack, fed with buried hardline. The vertical has sixty 120 ft
/archives//html/Topband/2018-12/msg00010.html (11,565 bytes)

73. Re: Topband: new style PL-259's with screw on back INSTRUCTIONS (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Wed, 5 Dec 2018 11:04:18 -0500
Finally, after years of frustration with several types of PL259 connectors, I've settled on the new crimp/solder type from DX Engineering. They're strong, reliable, and easy to install in minutes whi
/archives//html/Topband/2018-12/msg00026.html (12,368 bytes)

74. Re: Topband: Rather use N-type (was Re: The answer to PL-259 soldering/reliability problems) (score: 1)
Author: "Jim Garland" <4cx250b@miamioh.edu>
Date: Thu, 6 Dec 2018 09:23:53 -0700
About twenty-five years ago I started replacing many of my PL259 connectors with N-connectors. I did this mostly because my VHF/UHF buddies convinced me that the impedance bump of an N-connector was
/archives//html/Topband/2018-12/msg00054.html (17,767 bytes)

75. Re: Topband: Rather use N-type (was Re: The answer to PL-259 soldering/reliability problems) (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Fri, 7 Dec 2018 09:37:42 -0500
Interesting discussion, and I appreciate the many viewpoints. One consideration, when weighing N-connectors vs PL259s, is what happens to the cable after the connector is attached. Nobody disputes th
/archives//html/Topband/2018-12/msg00078.html (15,895 bytes)

76. Re: Topband: Updated K9YC common-mode choke PDF now available (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Wed, 23 Jan 2019 08:06:45 -0500
Very interesting, Jim. I wasn't familiar with RG-400, but I've used RG-142B for years. I compared the specs and found they're virtually identical, the only significant difference being that RG-400 ha
/archives//html/Topband/2019-01/msg00101.html (9,259 bytes)

77. Re: Topband: Updated K9YC common-mode choke PDF now available (score: 1)
Author: "Jim Garland" <4cx250b@miamioh.edu>
Date: Sun, 3 Feb 2019 10:01:16 -0700
Guy, I agree in principle that coax with a stranded center conductor will be more flexible than coax with a solid conductor, although in applications where there is mechanical stress on the coax, coa
/archives//html/Topband/2019-02/msg00040.html (12,628 bytes)

78. Re: Topband: BevFlex-4X - RX antenna (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Fri, 18 Oct 2019 05:51:21 -0700
On this general subject, Im using bi-diectional beverages 720 ft long, suspended 7 ft above sandy desert ground. The F/B ratio is poor (not important for New Mexico) but Im wondering if the antennas
/archives//html/Topband/2019-10/msg00144.html (10,573 bytes)

79. Re: Topband: Hardening the 8 Circle Receiving Array (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Fri, 18 Oct 2019 06:36:07 -0700
Ive had good luck using fast zener diodes in series with ordinary small silicon diodes (eg 1n914). The zener keeps the signal diode out of the antenna circuit until the zener breakdown voltage, say 1
/archives//html/Topband/2019-10/msg00146.html (10,858 bytes)

80. Re: Topband: Beverage Length vs F/B or (RDF?) (score: 1)
Author: MU 4CX250B <4cx250b@miamioh.edu>
Date: Fri, 18 Oct 2019 07:51:50 -0700
Thanks for the suggestion, Dave. Im using DXE hardware and relay boxes for switching, and twin lengths of WD-1A mil surplus telephone cable for the wires. The lengths are spaced roughly 6 inches apar
/archives//html/Topband/2019-10/msg00149.html (15,388 bytes)


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