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References: [ +from:n4is@comcast.net: 219 ]

Total 219 documents matching your query.

181. Topband: Dual loaded loop receiving antenna Historical Evolution (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Fri, 26 Feb 2021 11:27:50 -0500
Hi guys This is a collection of paper I was able to put together, please it is a working in progress and new entries are welcome. My eye is not doing well and it is hard for me to type, so this is a
/archives//html/Topband/2021-02/msg00143.html (10,486 bytes)

182. Topband: Receiver Equivalent Noise Bandwidth (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 26 Feb 2021 11:59:58 -0500
Here the procedure I used to measure my receiver equivalent bandwith to calculate NF. https://www.owenduffy.net/measurement/enb/MeasureIfBw.htm SpecrunLab is also a very good tool to measure EBW http
/archives//html/Topband/2021-02/msg00146.html (7,085 bytes)

183. Topband: Understanding or attempt to understand a flag antenna (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 26 Feb 2021 12:54:52 -0500
Hi Guys This concept is important and very confusing, so sorry for being a broken record. I?ll keep it very simple to understand. The Flag antenna and its variances, EWE, pennant WF SAL DHL and other
/archives//html/Topband/2021-02/msg00148.html (9,220 bytes)

184. Topband: Usable size of Flag antenna and FSM (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 26 Feb 2021 12:57:39 -0500
I would like to share some of my experience with small flags'. The directivity is the same for a large chance in frequency but the gain increase with size. As a reference NX4D started with a single f
/archives//html/Topband/2021-02/msg00149.html (9,985 bytes)

185. Re: Topband: Usable size of Flag antenna and FSM (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 26 Feb 2021 21:12:17 -0500
Hi Eric Congratulations, wow!! Great work. 73's JC N4IS Anti-phased double loops are also a good way to approach an RDF of 10dB on 2200m (137kHz). 1/2lambda is nearly 3600ft.... so broadside arrays a
/archives//html/Topband/2021-02/msg00160.html (8,908 bytes)

186. Re: Topband: Portable transmit antenna suggestions? (score: 1)
Author: <n4is@comcast.net>
Date: Wed, 10 Mar 2021 20:34:21 -0500
Hi Luke The best signal ever on 160m from that part of the world was possible and only possible with the vertical IN the salt water. The radials making electrical contact with the water. Pleas talk w
/archives//html/Topband/2021-03/msg00103.html (10,227 bytes)

187. Re: Topband: Screening Effect of Trees (score: 1)
Author: <n4is@comcast.net>
Date: Sat, 3 Apr 2021 15:28:07 -0400
Hi Roger That is a very important question and the answer may surprise a lot of folks on Topband. Kay KE4PT worked several years on Motorola simulation RF in hollow bodies for pagers and handheld clo
/archives//html/Topband/2021-04/msg00017.html (9,068 bytes)

188. Re: Topband: Great Engineering by AA7JV (score: 1)
Author: <n4is@comcast.net>
Date: Mon, 5 Apr 2021 23:13:38 -0400
You guys have no idea how many, not hours., days not month .. years of hard work George put in this project. It is a huge invention , a frontend to RX/TX CW 1824 and RXTX FT8 on 1840 at the same time
/archives//html/Topband/2021-04/msg00036.html (8,740 bytes)

189. Re: Topband: amp tripping on 160 (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Fri, 29 Oct 2021 11:17:21 -0400
My old friend N8PR(SK) had a similar problem. Peter QTH was few miles for a AM station. The SPE amp is very sensitive, the signal from the AM station was strong enough to trip the amp. The solution w
/archives//html/Topband/2021-10/msg00079.html (10,998 bytes)

190. Re: Topband: Beverage polarization (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Fri, 12 Nov 2021 11:25:00 -0500
Ron The short answer is simple. Beverage antenna is really a transmission line with all proprieties of a transmission line, in one side is terminated by a load and on the other side by a transformer.
/archives//html/Topband/2021-11/msg00061.html (9,538 bytes)

191. Re: Topband: Beverage polarization (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Fri, 12 Nov 2021 12:14:04 -0500
Thanks Jon I have one copy too. Electrical and Electronic Engineering series KRAUS ANTENNAS page 412. 14-11 Beverage or Wave Antenna. 73.s JC N4IS Sent from Mail for Windows This subject is well cove
/archives//html/Topband/2021-11/msg00063.html (11,762 bytes)

192. Re: Topband: K9AY Loop Questions (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Thu, 6 Jan 2022 22:23:13 -0500
Don Im afraid your information is not accurate, SAL is the same as a K9AY, the two wires close to each other can be removed because they cancel each other. The remain wires works like two vertical in
/archives//html/Topband/2022-01/msg00031.html (12,725 bytes)

193. Re: Topband: K9AY Loop Questions (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 7 Jan 2022 10:07:16 -0500
Hi Andrew He concept is very simple, you can phase 2 verticals. 3 verticals or 4 vertical. See you got, two verticals in phase give you a cardioid pattern, only one deep null on the back. Moving to 3
/archives//html/Topband/2022-01/msg00042.html (10,575 bytes)

194. Re: Topband: K9AY Loop Questions (score: 1)
Author: <n4is@comcast.net>
Date: Fri, 7 Jan 2022 10:27:16 -0500
Hi Don That's a very interesting question. The K9AY is ground dependent. The reason is simple, the Loaded loop of flag has a resistor in one side and the transformer on the other side. If you want to
/archives//html/Topband/2022-01/msg00043.html (18,315 bytes)

195. Re: Topband: K9AY Loop Questions (score: 1)
Author: Jose_Carlos <N4IS@COMCAST.NET>
Date: Fri, 7 Jan 2022 19:59:43 -0500
Sent from Mail for Windows Hi Andrew In this case it is very important to consider that both antennas are close to the ground. It means the reflection from the ground is different for vertical vector
/archives//html/Topband/2022-01/msg00051.html (10,108 bytes)

196. Re: Topband: Series LC to notch AM broadcast ? (score: 1)
Author: <n4is@comcast.net>
Date: Sun, 20 Feb 2022 19:16:32 -0500
band..... like 1200-1710 khz. << I built several HP filters with >40 db attenuation on 1.7 KHz based on QST, I don't remember the year 90's about it. But some good information here > https://www.qsl
/archives//html/Topband/2022-02/msg00093.html (8,192 bytes)

197. Re: Topband: J28MD, conditions (score: 1)
Author: <n4is@comcast.net>
Date: Sat, 5 Nov 2022 19:08:02 -0400
"The WSJT Modes, including FT8 and FT4, require a live operator" I am sorry to disagree, any "ROBOT" that you can buy on e-Bay, with your call sign, for $25 make the human operator 100% optional. Sev
/archives//html/Topband/2022-11/msg00014.html (8,224 bytes)

198. Re: Topband: Dipole/remote tuner (score: 1)
Author: <n4is@comcast.net>
Date: Sat, 12 Nov 2022 14:55:20 -0500
Jake One very simple solution is a double inverted V. I built and used this antenna for several years. The SWR can be 1:1.5 or lower from 3.5 to 3.8 MHz. The basic principal is a double dipole spaced
/archives//html/Topband/2022-11/msg00051.html (8,527 bytes)

199. Topband: FW: Band conditions (score: 1)
Author: "JC" <n4is@comcast.net>
Date: Wed, 16 Nov 2022 18:22:00 -0500
One common misunderstanding is that propagation on low bands is bad when high bands are good. When solar activity is high, the solar flux increase and allows F2 reflection on the high bands , 15.12 a
/archives//html/Topband/2022-11/msg00067.html (7,499 bytes)

200. Re: Topband: Radials, EZNEC and far field (score: 1)
Author: <n4is@comcast.net>
Date: Tue, 20 Dec 2022 07:25:35 -0500
Hi Frank You wrote " . A vertical over a salt marsh or within about a wavelength of salt water will produce 6 dB or more of gain at low angles compared to a vertical with poorly conducting soil in it
/archives//html/Topband/2022-12/msg00094.html (8,339 bytes)


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