- 361. Re: Topband: Lazy question concerning toroidal inductors (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Mon, 06 Aug 2012 08:57:48 -0700
- Not enough information. How many turns? How much current through inductor? What core size? What material? Do you already have a particular core you want to design around? What Q do you need from the
- /archives//html/Topband/2012-08/msg00134.html (9,739 bytes)
- 362. Re: Topband: RX 4 SQ Phasing (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Fri, 10 Aug 2012 10:59:55 -0700
- A while back, I built a 4X2 low band array of receive verticals aimed at Europe via Canada, but reversible to beam over San Francisco. I could tune to 960 kHz and listen to a San Francisco station 70
- /archives//html/Topband/2012-08/msg00158.html (7,944 bytes)
- 363. Re: Topband: RX 4 SQ Phasing (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Fri, 10 Aug 2012 17:14:45 -0700
- My ground is high conductivity according to the FCC map, so maybe that doesn't explain the performance. Rick N6RK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? B
- /archives//html/Topband/2012-08/msg00167.html (7,922 bytes)
- 364. Re: Topband: RX 4 SQ Phasing (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Sun, 12 Aug 2012 22:27:09 -0700
- Yes, but I have also measured the current drop off with distance on my beverages and it agrees with the high conductivity assumption. Any wire beyond 400 feet on a beverage is ineffective here; I ins
- /archives//html/Topband/2012-08/msg00203.html (9,275 bytes)
- 365. Re: Topband: Relays for Outdoor Use (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Fri, 24 Aug 2012 14:43:13 -0700
- See QST, May 2009, Page 66. Rick N6RK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
- /archives//html/Topband/2012-08/msg00298.html (6,931 bytes)
- 366. Re: Topband: Wideband Balun...? (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 28 Aug 2012 13:12:29 -0700
- Basically, you are describing the old Heathkit balun. It has two bifilar air core coils and is designed to convert 75 ohms to 300 ohms. Covers 80 through 10 meters. (Not 160 meters). You could probab
- /archives//html/Topband/2012-08/msg00324.html (8,093 bytes)
- 367. Re: Topband: Dog fence parameter radial wire (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Wed, 26 Sep 2012 20:30:13 -0700
- I have an inverted L in the trees of my back yard with 30 radials. The length of the radials is 70 feet since this is what I could fit into the existing area. I lay my radials on the ground since the
- /archives//html/Topband/2012-09/msg00278.html (9,343 bytes)
- 368. Re: Topband: K6STI low noise receive loop (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Tue, 02 Oct 2012 16:22:33 -0700
- And, in my case, Don, I simply need to put up an antenna that's: a) more efficient than my vertical and b) fits within the confines of my property....having any noise cancelling or nulling is a plus
- /archives//html/Topband/2012-10/msg00090.html (9,407 bytes)
- 369. Re: Topband: Vertical with elevated transmission line? (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Thu, 25 Oct 2012 21:35:16 -0700
- FWIW, this is what I do. I have 450 ohm line 5 feet high over a mesh ground screen. There is a balun at the end of the line and coax drops down onto the mesh for the final few feet to the feed point.
- /archives//html/Topband/2012-10/msg00357.html (7,613 bytes)
- 370. Re: Topband: dipole height (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 30 Oct 2012 10:13:19 -0700
- I had full size 160M dipoles (not inverted vees) up at 9 meters and 18 meters for about six months and did a lot of A/B'ing of them. On receive, there was never any difference in audible S/N ratio. T
- /archives//html/Topband/2012-10/msg00368.html (7,308 bytes)
- 371. Re: Topband: dipole height (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 30 Oct 2012 13:33:23 -0700
- I am well aware of this, which is why I put relays at the feed points to open up the dipole that was not in use. An isolated pair of 1/4 wave wires has virtually no effect on a nearby dipole. Rick N6
- /archives//html/Topband/2012-10/msg00371.html (8,106 bytes)
- 372. Re: Topband: dipole height (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Wed, 31 Oct 2012 14:57:31 -0700
- This is why anecdotal reports of great receiving antennas should be taken with a grain of salt. If the user had a dominant noise source in one direction, a receiving antenna with modest RDF, but with
- /archives//html/Topband/2012-10/msg00400.html (10,002 bytes)
- 373. Re: Topband: Tuning 160M Dipole (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Wed, 31 Oct 2012 15:04:54 -0700
- It works a lot better to find the frequency of minimum SWR and then it is a simple matter to calculate how much to prune. For example, if the frequency is 10% too low, say 1647 kHz, then remove 10%
- /archives//html/Topband/2012-10/msg00401.html (7,771 bytes)
- 374. Re: Topband: TX/ RX Antenna Switching (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Wed, 14 Nov 2012 17:21:19 -0800
- Lots of good points, Tom. The problem is basically the same as a QSK linear. Most modern rigs have a pin on the back that goes low about 10 ms before any RF comes out of the rig. Common reed relays l
- /archives//html/Topband/2012-11/msg00211.html (10,670 bytes)
- 375. Re: Topband: Limiters - not T/R Relays (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Thu, 15 Nov 2012 12:16:05 -0800
- What is interesting about this is that it uses T1-6 transformers, which I have been using and recommending for years for RX antenna use. I have repeatedly been told that these are no good because the
- /archives//html/Topband/2012-11/msg00237.html (7,821 bytes)
- 376. Re: Topband: Looking to improve TX antenna Efficiency (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 20 Nov 2012 11:45:03 -0800
- This type of question is hard to answer because we don't know what you are able to do. If you are able to do it, I would suggest changing from an inverted L to a T top loaded vertical. This suppresse
- /archives//html/Topband/2012-11/msg00332.html (8,074 bytes)
- 377. Topband: Is PT0S still on 160M? (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 20 Nov 2012 19:23:24 -0800
- They were on a lot last week, but I have seen very few spots the last few days. Are they "finished" with 160 meters? The original plan was to be on during all dark time. Rick N6RK ___________________
- /archives//html/Topband/2012-11/msg00341.html (7,218 bytes)
- 378. Re: Topband: how high are very high voltages on antennas? (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Wed, 21 Nov 2012 21:58:10 -0800
- I used to have a 130 foot end fed wire. At 1.5 kW, it had over 2,000 VRMS on 80 meters. I used a fixed 120 pF vacuum capacitor and a 6 inch diameter coil as a matching network. If you use a big 240VA
- /archives//html/Topband/2012-11/msg00351.html (7,923 bytes)
- 379. Re: Topband: how high are very high voltages on antennas? (score: 1)
- Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
- Date: Thu, 22 Nov 2012 11:45:27 -0800
- with the antenna. An MFJ screwdriver controller provides 10 preset turns counts, established at 20KHz steps by manually measuring swr. I use the MFJ controller on my Tornado variable inductor tuned
- /archives//html/Topband/2012-11/msg00361.html (7,913 bytes)
- 380. Re: Topband: Remote SDR Receive only setup (score: 1)
- Author: "Rick Karlquist" <richard@karlquist.com>
- Date: Tue, 27 Nov 2012 10:19:12 -0800
- I have run a remote base (not just receiving) for many years and prefer a very boring, non-state-of-the-art approach of simply controlling a radio remotely and feeding the audio back over landline te
- /archives//html/Topband/2012-11/msg00408.html (9,384 bytes)
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