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161. [TenTec] TWINCOM feedline ????????????? (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 15 Oct 2002 12:54:40 -0500; The wider the space the more the feed line radiates. The thin spacers of the TWINWIRE compared to the plastic ladder lines means its less affected by wind, and maybe by ice. I've used flat lines for; /archives//html/TenTec/2002-10/msg00285.html (9,997 bytes)
162. [TenTec] Re: parallel lines rated by losses (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 15 Oct 2002 13:10:16 -0500; If you neglect the radiation losses of the wide spaced open wire lines on the higher frequencies, there are no bends in the line, and there are no intrusions into the space about the line, open wire; /archives//html/TenTec/2002-10/msg00287.html (9,395 bytes)
163. [TenTec] TWINCOM feedline ????????????? (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 15 Oct 2002 19:57:41 -0500; But a wide spaced line WILL radiate. Antennas are made of slightly wider spaced parallel lines, for example the Quad, where the spacing is quarter wave. The connectors top and bottom (if horizontally; /archives//html/TenTec/2002-10/msg00292.html (11,710 bytes)
164. [TenTec] TWINCOM feedline ????????????? (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 16 Oct 2002 18:48:32 -0500; The classic transmission line theory that the fields cancel at all points in space IS a convenient ARTIFICE but its NOT absolutely true. When the conductors are at different distances from the observ; /archives//html/TenTec/2002-10/msg00313.html (11,116 bytes)
165. [TenTec] Re: TWINCOM feedline? (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Thu, 17 Oct 2002 09:44:55 -0500; A radiating feedline can cause TVI by radiating closer to the faulty TV than the elevated and relatively remote antenna. In some areas, the neighbor's TVs aren't very far from the ham station. There; /archives//html/TenTec/2002-10/msg00322.html (8,330 bytes)
166. [TenTec] Digital readout Corsair II (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Sun, 27 Oct 2002 20:52:18 -0600; Check the 5 volt supply to the CPU that drives the readout. Check the frequency lines from the band switch, and check or replace all the aluminum electrolytics in that readout driver. Old aluminum el; /archives//html/TenTec/2002-10/msg00543.html (7,058 bytes)
167. [TenTec] QA - Filters: (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Mon, 28 Oct 2002 23:15:32 -0600; I have, on several occasions. You might check the archives or ask again tomorrow. Its too late tonight to type all my opinions. There are crystal lattice filters and ladder filters (Tentec uses ladde; /archives//html/TenTec/2002-10/msg00579.html (7,837 bytes)
168. [TenTec] Receivability (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 30 Oct 2002 10:11:51 -0600; Lattice filter dynamic range is limited by the linearity of the crystals and the transformer cores. Extremely tiny cores may saturate far more easily than large cores, so that miniature filters may n; /archives//html/TenTec/2002-10/msg00601.html (8,751 bytes)
169. [TenTec] Receivability (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 30 Oct 2002 10:12:04 -0600; To maintain dynamic range its necessary that the diode ring mixer (and surely FET mixers that switch like a diode ring) be terminated broad band. Otherwise the undesired signals and output products (; /archives//html/TenTec/2002-10/msg00602.html (12,926 bytes)
170. [TenTec] [OT] re: 50hz PSK filter? (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 30 Oct 2002 11:33:22 -0600; It all depends on the dynamic range of the receiver and the DSP. If the strong signals passing through the receiver but rejected by the external DSP cause the receiver gain to drop so low as to loose; /archives//html/TenTec/2002-10/msg00604.html (7,543 bytes)
171. [TenTec] Define RX intercept, please. (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Fri, 02 Aug 2002 21:18:37 -0500; You should be reading recent ARRL handbooks. There's a chapter on receiver testing and performance. There are many other useful chapters also. 73, Jerry, K0CQ -- Entire content copyright Dr. Gerald N; /archives//html/TenTec/2002-08/msg00033.html (6,685 bytes)
172. [TenTec] TenTec 524 (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Mon, 05 Aug 2002 20:55:56 -0500; I'm working on the concept but I'm slow this year. May have something for future CSVHF conferences. 73, Jerry, K0CQ -- Entire content copyright Dr. Gerald N. Johnson, electrical engineer. Reproductio; /archives//html/TenTec/2002-08/msg00097.html (6,689 bytes)
173. [TenTec] Scout field/mobile (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Fri, 09 Aug 2002 22:46:15 -0500; When used mobile you want fuses in both positive and ground to protect the radio when the engine to frame jumper breaks and starter current tries to pass through coax and radio. Breakers are more con; /archives//html/TenTec/2002-08/msg00157.html (6,727 bytes)
174. [TenTec] RF Spectrum Analyzer (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 13 Aug 2002 13:36:43 -0500; Some of the classic spectrum analyzers from HP, such as those using the HP141 scope for display also include x y recorder outputs. Those are fairly easy to interface to a PC for display. There was an; /archives//html/TenTec/2002-08/msg00233.html (7,787 bytes)
175. [TenTec] Optical Encoder operation (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 13 Aug 2002 14:51:58 -0500; There are two sensors, that are positioned so their outputs change alternately. The sequence then shows direction. In discrete logic it takes about two quad logic chips to take the two outputs and pr; /archives//html/TenTec/2002-08/msg00241.html (7,901 bytes)
176. [TenTec] WGA or Heil for Scout (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 14 Aug 2002 08:45:32 -0500; There are several ways to cure microphone "bassiness." The simplest is to back away from the microphone. That enhanced bassiness is why pop singers swallow their hand microphone. Back off and it gets; /archives//html/TenTec/2002-08/msg00267.html (8,133 bytes)
177. [TenTec] WGA or Heil for Scout (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Sun, 18 Aug 2002 12:19:20 -0500; Capacitor shaping can work a great deal. That's all there is in the fanciest equalizer, just multiple RC and op amps to make their effects stronger. Simple RC using the circuit impedance for the R an; /archives//html/TenTec/2002-08/msg00324.html (9,097 bytes)
178. [TenTec] RC shaping was WGA or Heil for Scout (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Sun, 18 Aug 2002 22:36:44 -0500; The resistances need not be changed, that way the mid range level stays constant. Only the series and shunt capacitors need to change to modify the low and high roll off frequencies. With the lows an; /archives//html/TenTec/2002-08/msg00335.html (9,816 bytes)
179. [TenTec] Scout,Omni,TS 850 transmit (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Sat, 24 Aug 2002 09:43:19 -0500; Poor transmitter intermod is noticed first by users of adjacent frequencies as monkey chatter and splatter. IN the ault days of tube finals going for third order of -30 gave a super 5th order and the; /archives//html/TenTec/2002-08/msg00419.html (8,784 bytes)
180. [TenTec] Paragon VFO Problem (score: 1): Author: geraldj@isunet.net (Dr. Gerald N. Johnson, electrical engineer); Date: Sat, 24 Aug 2002 09:43:36 -0500; Standard Tentec VFO wear. Needs a rebuild. Kit from TenTec about $23, takes about 3 hours to do the first one. Sometimes cleaning and regreasing works, but my CorsairII had a very worn ball reduction; /archives//html/TenTec/2002-08/msg00420.html (8,109 bytes)

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