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Total 357 documents matching your query.

341. Re: [TenTec] Re: Rudimentary SWR question... (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 21 Oct 2003 15:29:06 -0500
DL6WU long yagis are designed to give a plain dipole driven element center Z of about 50 ohms. Makes for less loss and easier feeds. Some computer optimized (and commercial) medium length VHF yagis h
/archives//html/TenTec/2003-10/msg00664.html (11,300 bytes)

342. Re: [TenTec] Re: ~ 1/4 wave 160 doublet (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 21 Oct 2003 17:16:50 -0500
That applies here. The antenna won't work a bit better with the added feedline, just the tuner will be easier to tune. And that's why those magic lengths are no longer described in modern antenna man
/archives//html/TenTec/2003-10/msg00669.html (7,978 bytes)

343. Re: [TenTec] Latest BPL events... (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Thu, 23 Oct 2003 17:31:53 -0500
We taught the foreign power systems how to use 3 phase and we use three phase all over except for individual single phase lines to single phase customers. But when the wires are more than an antenna
/archives//html/TenTec/2003-10/msg00739.html (7,961 bytes)

344. Re: [TenTec] Latest BPL events... (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Fri, 24 Oct 2003 09:31:44 -0500
Jason W0JSB: Your residential distribution is single phase. Much of the ground wire current is in the earth. The 75 stands for 75 KVA transformer rating. The primary voltage might be 4160, might be 2
/archives//html/TenTec/2003-10/msg00753.html (9,980 bytes)

345. Re: [TenTec] Latest BPL ....power distribution for AC (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Fri, 24 Oct 2003 19:42:20 -0500
Those capacitors aren't for phase shifting to make a pseudophase, they are for power factor correction to improve the voltage regulation. Phase shifting with capacitors is very load dependent and use
/archives//html/TenTec/2003-10/msg00769.html (9,125 bytes)

346. Re: [TenTec] QRP-ifying an IC-745 and TT 1208 Transverter (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Sun, 26 Oct 2003 13:23:41 -0600
I don't know the circuit details of the TT1208 but I presume the IF port is quite similar to that of the TT1209 with the same IF port ratings. I've driven my TT1209 with a HP608F signal generator at
/archives//html/TenTec/2003-10/msg00792.html (8,025 bytes)

347. Re: [TenTec] 560 Problem (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Mon, 27 Oct 2003 21:35:54 -0600
The RF stage transistor could be bad, fried by lightning. The amplifier switching could be bad. The same components are used on all bands. You do need a schematic from the manual to find those parts
/archives//html/TenTec/2003-10/msg00823.html (7,428 bytes)

348. Re: [TenTec] 560 Problem (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 28 Oct 2003 16:44:56 -0600
There are two virtually identical stages in my Corsair II schematic. The RF stage and the first IF stage, both high dynamic range transformer feedback (Anzac patent) bipolar stages using CATV rf powe
/archives//html/TenTec/2003-10/msg00848.html (8,338 bytes)

349. Re: [TenTec] Omni 6+ / Inrad SSB mod (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Fri, 31 Oct 2003 09:43:27 -0600
What 3 kHz spacings rules. There never have been RULES about spacings on amateur bands. 3 kHz works with 2.4 and 2.1 KHz filters (2.1 was the standard Collins S-line filter, plenty good for communica
/archives//html/TenTec/2003-10/msg00895.html (8,101 bytes)

350. Re: VS: [TenTec] Orion TX Audio: Update (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Fri, 31 Oct 2003 09:43:30 -0600
Depends on whether you are trying to avoid a 50/60Hz ground loop or RF. In the ham shack where the radio filter ignores that low frequency, and there IS RF, grounding the shield at the radio end to t
/archives//html/TenTec/2003-10/msg00896.html (8,849 bytes)

351. Re: [TenTec] 3KC Spacing / K0CQ reply (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Fri, 31 Oct 2003 22:25:49 -0600
I have a home brew speaker passive filter. One choice of cutoff frequency is about 1850 Hz. Its quite useful for enhancing weak signals and hiding QRM. 2 KHz spacing works with fine radios having sup
/archives//html/TenTec/2003-10/msg00929.html (8,934 bytes)

352. Re: [TenTec] Inrad Mods/ Reply to Ken Brown (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 04 Nov 2003 14:35:15 -0600
2.8 KHz is a third wider than the 2.1 filter that came in all 100,000+ Collins S-line and a large number of KWM-2. I never noticed not copying nice audio with them though listing to very narrow FM wi
/archives//html/TenTec/2003-11/msg00085.html (8,984 bytes)

353. Re: [TenTec] Inrad Mods/ Reply to Ken Brown (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 04 Nov 2003 21:33:18 -0600
Bandpass tuning in the 75A4 was expensive to produce. The 75A4 and KWS-1 were intended only for the elite amateur, and priced accordingly. That bandpass tuning was different than the band pass tuning
/archives//html/TenTec/2003-11/msg00099.html (11,541 bytes)

354. Re: [TenTec] Inrad Mods (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Wed, 05 Nov 2003 10:50:20 -0600
Collins Yellow Book suggests that voice components above 1 kHz contribute most to intelligibility while the lower frequency components contribute most of the power. Therefore they suggest that the HF
/archives//html/TenTec/2003-11/msg00116.html (7,656 bytes)

355. Re: VS: [TenTec] Fixing a Paragon... (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Wed, 05 Nov 2003 23:17:50 -0600
As I recall reading on this list, Paragon logic boards have had a tendency to suffer from poor soldering and many miscellaneous problems have been fixed by simply manually resoldering every connectio
/archives//html/TenTec/2003-11/msg00136.html (8,285 bytes)

356. Re: [TenTec] Minimum power necessary (long) (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Thu, 06 Nov 2003 10:45:25 -0600
Yes, there are differing opinions on the required bandwidth. And indeed the required bandwidth depends on the nature of the communication AND the voice. A kid or YL is going to need more top end to b
/archives//html/TenTec/2003-11/msg00155.html (12,727 bytes)

357. Re: [TenTec] TT 1220 problem (score: 1)
Author: "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>
Date: Tue, 11 Nov 2003 22:58:04 -0600
Sounds to me as if its a PLL loop filter problem. Check those capacitors and resistors between the phase detector, the op amp if any, and the VCO. Check board grounding also, e.g. tightness of board
/archives//html/TenTec/2003-11/msg00284.html (7,532 bytes)


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