Search String: Display: Description: Sort:

Results:

References: [ +from:richard@karlquist.com: 1580 ]

Total 1580 documents matching your query.

381. Re: [TowerTalk] 1 dB difference (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Tue, 15 May 2007 11:37:47 -0700 (PDT)
Even if 1 dB by itself is unnoticable, the sum of multiple 1 dB improvements will be noticable. Thus if you pick up ~1 dB by using a legal limit (1500W) amplifier instead of 1200W, and a ~half dB of
/archives//html/Towertalk/2007-05/msg00406.html (7,487 bytes)

382. Re: [TowerTalk] Rohn 45 Unique Installation (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Fri, 18 May 2007 10:15:47 -0700
I had a TH6 on 60 ft of Rohn 25 up for 3 years in Seattle on a 30 ft lot. The guys were at steep angles. It went through lots of big storms with no problem. The guy anchors were screw in earth type a
/archives//html/Towertalk/2007-05/msg00462.html (10,216 bytes)

383. Re: [TowerTalk] US Tower MA550 Coax Feedline (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Fri, 18 May 2007 13:59:32 -0700 (PDT)
I happen to have an MA550 tower but this posting is about my 106 ft HDX5106 tower. I am using large coax (7/8" OD) on this tower and made two decisions about this: 1. Instead of using the stock coax
/archives//html/Towertalk/2007-05/msg00467.html (8,484 bytes)

384. Re: [TowerTalk] Driving ground rods in rocky soil (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 24 May 2007 14:10:29 -0700 (PDT)
At our place, we have "cemented hard pan" that is totally waterproof. You can soak it for 3 months and nothing will happen to it. Only a carbide masonry bit will bore a hole in it. Rick N6RK ________
/archives//html/Towertalk/2007-05/msg00529.html (8,422 bytes)

385. Re: [TowerTalk] AIM 4170 (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 24 May 2007 15:43:11 -0700 (PDT)
Yes, I tried an AIM4170. It is knocked out by a 50 kW station @ 6 miles on my 160 vertical. It might work with a filter installed, however, it is necessary to calibrate out the filter. Unfortunately,
/archives//html/Towertalk/2007-05/msg00537.html (8,276 bytes)

386. Re: [TowerTalk] AIM 4170 (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 24 May 2007 18:30:16 -0700 (PDT)
The N2PK VNA is a great design, but it is not available even as a kit, you have to homebrew it. If I knew then what I know now about the AIM4170 I probably would have considered building the N2PK des
/archives//html/Towertalk/2007-05/msg00546.html (8,184 bytes)

387. Re: [TowerTalk] tubing vs pipe (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Thu, 31 May 2007 19:08:26 -0700
Correction: Pipe is also measured outside. For example, all so-called "2 inch" (Iron Pipe Size) pipe is 2 3/8 inch O.D., regardless of wall thickness. The I.D. varies from below 2 inches to above 2 i
/archives//html/Towertalk/2007-05/msg00630.html (9,691 bytes)

388. Re: [TowerTalk] tubing vs. pipe-- and a question (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Fri, 1 Jun 2007 08:50:37 -0700
This is only approximately correct. "2 inch" Iron Pipe Size (IPS) pipe does not have exactly a 2" ID. All 2 inch pipe has an OD of exactly 2 3/8 inch. The ID depends on wall thickness (ie schedule 4
/archives//html/Towertalk/2007-06/msg00010.html (12,027 bytes)

389. Re: [TowerTalk] masts. (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Fri, 1 Jun 2007 15:46:00 -0700 (PDT)
The 1.9" OD is "1.5 inch iron pipe size" and the 2 3/8" OD is "2 inch iron pipe size". Rick N6RK _______________________________________________ _______________________________________________ TowerT
/archives//html/Towertalk/2007-06/msg00028.html (8,276 bytes)

390. Re: [TowerTalk] RE : tubing vs pipe (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Fri, 1 Jun 2007 22:04:46 -0700
WRONG WRONG WRONG. Take a pair of calipers to any plumbing supply store and measure schedule 40 and schedule 80 pipe. Same OD, different ID. And neither equal the iron pipe size. Google "plumbing" f
/archives//html/Towertalk/2007-06/msg00050.html (8,405 bytes)

391. Re: [TowerTalk] tubing vs. pipe-- and a question (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Fri, 1 Jun 2007 22:15:05 -0700
"One inch" pipe does NOT have an ID of 1". It's actually about 1.05" for schedule 40, less than 1" for schedule 80. You are correct that both PVC and iron pipe have the same OD, which is 1.33 inches
/archives//html/Towertalk/2007-06/msg00051.html (8,504 bytes)

392. Re: [TowerTalk] Yagis (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Sat, 2 Jun 2007 18:54:41 -0700
The funny thing about HyGain and most other manufacturers is that 20 meter beams are relatively close spaced and 10 meter beams are wide spaced. Thus a 10 meter 4 element beam could easily have a bo
/archives//html/Towertalk/2007-06/msg00059.html (8,471 bytes)

393. Re: [TowerTalk] Direct burial rotor cable needed (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Tue, 5 Jun 2007 10:08:21 -0700 (PDT)
While at HD, etc., also look at low voltage patio lights. They have heavy gauge zip cord that is buryable. I think 12 gauge. Rick N6RK _______________________________________________ ________________
/archives//html/Towertalk/2007-06/msg00087.html (9,229 bytes)

394. Re: [TowerTalk] Voltage at feedpoint (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Tue, 5 Jun 2007 17:03:49 -0700 (PDT)
The stress on the balun is also due to the severe mismatch of a 40 meter dipole on 60 meters. This results in high currents and voltages for a given power. The currents and voltages are manageable at
/archives//html/Towertalk/2007-06/msg00105.html (8,574 bytes)

395. Re: [TowerTalk] elevated radials vertical (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Sun, 10 Jun 2007 07:39:06 -0700
I once made very careful measurements of a 40 meter vertical using 4, 8, 15, 30, 60 and 120 radials. Each time I added radials, there was an improvement, except from 60 to 120. No measureable differ
/archives//html/Towertalk/2007-06/msg00185.html (9,201 bytes)

396. Re: [TowerTalk] step away from stepIR (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Tue, 12 Jun 2007 13:19:56 -0700 (PDT)
If you read the SteppIR docs you will quickly see that the element drive impedance is not 50 ohms but 22 ohms. There is a transformer/balun to get back to 50 ohm coax. A driven element impedance of 2
/archives//html/Towertalk/2007-06/msg00350.html (9,142 bytes)

397. Re: [TowerTalk] RF current meter (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Fri, 15 Jun 2007 22:52:48 -0700 (PDT)
Tektronix sells various current probes, some AC coupled, some DC coupled, some clip on and some where you have to pass a wire through them. I own various models of these. They do not add any signific
/archives//html/Towertalk/2007-06/msg00487.html (11,190 bytes)

398. Re: [TowerTalk] MA550 tubular tower (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Mon, 18 Jun 2007 07:21:27 -0700
I built a dolly out of 4x4's and a couple of wheelbarrow tires. If you balance it in the middle, one person can wheel it around on level ground. You can use a car jack to lift it up to get it onto th
/archives//html/Towertalk/2007-06/msg00551.html (10,043 bytes)

399. Re: [TowerTalk] Fwd: Re: vertical ground experiment (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 21 Jun 2007 16:00:46 -0700 (PDT)
The 36 ohm number is for a infinitesimally thin vertical that is 1/4 wave high as measured in free space wavelengths (and hence will be somewhat off resonance). Fat verticals have considerably lower
/archives//html/Towertalk/2007-06/msg00690.html (11,178 bytes)

400. Re: [TowerTalk] Fwd: Re: vertical ground experiment (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 21 Jun 2007 16:30:27 -0700 (PDT)
One of the reasons why the feedpoint impedance doesn't necessarily correlate with the efficiency is that there isn't necessarily any well defined location that represents a line of demarcation betwee
/archives//html/Towertalk/2007-06/msg00694.html (10,622 bytes)

Current List: 381 - 400
Page: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20]
This search system is powered by Namazu