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61. [TenTec] TUNER? (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Fri, 26 Jan 2001 10:33:07 -0600
Tuners DO NOT tune the antenna through the feed line. A tuner AT the antenna sometimes can affect an antenna resonance. Tuners adjust the antenna impedance as seen through the feed line to something
/archives//html/TenTec/2001-01/msg00654.html (8,036 bytes)

62. [TenTec] rombics and v-beams (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Mon, 29 Jan 2001 10:02:22 -0600
That's because they have many side lobes in all directions from the main lobe. 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting.com Administrative re
/archives//html/TenTec/2001-01/msg00737.html (6,710 bytes)

63. [TenTec]Tuners and ladder line in the shack (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Tue, 30 Jan 2001 13:21:14 -0600
I've found that shielded twin leads such as Belden 8290 (Unobtanium) or maybe something like that from RS can handle at least 200 watt continuous power (I dissipated 200 watts into a shorted section
/archives//html/TenTec/2001-01/msg00764.html (8,630 bytes)

64. [TenTec]Tuners and ladder line in the shack (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Tue, 30 Jan 2001 17:05:45 -0600
What's wrong with 180 twinlead made of two pieces of 93 ohm coax or 150 ohm twinlead made of two pieces of RG-11 other than the low impedance might lead to a low impedance at the tuner? 73, Jerry, K0
/archives//html/TenTec/2001-01/msg00770.html (8,401 bytes)

65. [TenTec] Remote 4:1 Balun (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Wed, 31 Jan 2001 13:28:55 -0600
Not necessarily true. SWR changes can come from changes in dielectric constant, not changes in loss. Changes in dielectric constant along a feed line will change its characteristic impedance. Clean r
/archives//html/TenTec/2001-01/msg00790.html (7,977 bytes)

66. [TenTec] SWR and Rain (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Wed, 31 Jan 2001 13:45:04 -0600
Not necessarily true! Losses at the feed line insulators will LOWER the impedance of the load through the transmission line but may either RAISE or LOWER the SWR as seen at the feed point according t
/archives//html/TenTec/2001-01/msg00792.html (9,048 bytes)

67. [TenTec] SWR and Rain (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Wed, 31 Jan 2001 15:11:02 -0600
The loss changes are frequency dependent. Maximum loss from water in coax is at about 650 MHz, but severe at 440 MHz. At lower frequencies the mismatch may obscure the added losses or be obscured by
/archives//html/TenTec/2001-01/msg00799.html (9,032 bytes)

68. [TenTec] Corsair II keyer problem (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sat, 02 Dec 2000 16:06:07 -0600
Sounds to me as if the socket pin or a trace is going open between the chip and the key connector. I'd check the traces by jumpering with a clip lead using minigator clips. If there's not a pull up r
/archives//html/TenTec/2000-12/msg00020.html (9,404 bytes)

69. [TenTec] Corsair II keyer problem (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 03 Dec 2000 10:10:00 -0600
Sounds to me as if its internal to the chip. Two choices, new chip or use an external keyer. 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting.com Adm
/archives//html/TenTec/2000-12/msg00022.html (7,639 bytes)

70. [TenTec] Pegasus vs. Heil Gold-Line and W2IHY Eq. (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Wed, 06 Dec 2000 19:37:53 -0600
Do you have a dummy load on the radio? Often ALC is also a sign of high swr. 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting.com Administrative requ
/archives//html/TenTec/2000-12/msg00056.html (7,308 bytes)

71. [TenTec] Optimus PRO-50MX & OMNI VI (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sat, 09 Dec 2000 18:33:00 -0600
I don't know about the Omni VI+, but I know the Corsair II is high impedance. That dynamic microphone is low impedance. Try adding a low to high impedance transformer from Radio Shack's PA equipment
/archives//html/TenTec/2000-12/msg00144.html (6,983 bytes)

72. [TenTec] TT Scout on batteries? (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 10 Dec 2000 10:55:38 -0600
Sounds to me as if the Scout has a 7810 or LM340-10 regulator for the VFO. That regulator needs about 2.5 volts headroom input to output to maintain regulation. Very likely the TO-92 version 78L10. I
/archives//html/TenTec/2000-12/msg00152.html (9,287 bytes)

73. [TenTec] Use of Battery DC-DC converter? (EX Scout Batteries) (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 10 Dec 2000 14:58:08 -0600
There are a number of semi-older MAXIM step up regulator chips made for use with external power MOSFETs that could raise the input voltage a couple volts. Its hard to do it absolutely quietly because
/archives//html/TenTec/2000-12/msg00156.html (8,338 bytes)

74. [TenTec] TT Scout on batteries? (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 10 Dec 2000 14:58:13 -0600
If the LM2940 is true of all Scouts (its was pin and mounting interchangeable with the LM7810 that would guarantee that 12.8 volt limit without fuse and connector drop). 1.1 volt drop through the con
/archives//html/TenTec/2000-12/msg00157.html (12,880 bytes)

75. [TenTec] BATTERY POWER (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 10 Dec 2000 16:24:49 -0600
To produce 50 watts RF, its likely the Scout draws 10 or 12 amps at 13.8 volts. When your energy depends on power of back to haul the gel cells or power of feet to crank a generator or power of the b
/archives//html/TenTec/2000-12/msg00160.html (8,092 bytes)

76. [TenTec] TT Scout on batteries? (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Sun, 10 Dec 2000 17:07:55 -0600
While much harder to find than the ubiquitous 9, 15, or 25 pin D there is a variation with a couple fat pins for high current or coax plus sometimes some control pins. I didn't find them in Digi-Key
/archives//html/TenTec/2000-12/msg00162.html (10,104 bytes)

77. [TenTec] Check out Ultra Miniature DC-DC converters (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Mon, 11 Dec 2000 20:24:51 -0600
Well if you buy a special, that's enough power for the oscillators, if you separate the circuits internally. It might be more productive to fix the voltage drop problems in the fuse holder and power
/archives//html/TenTec/2000-12/msg00174.html (7,047 bytes)

78. [TenTec] TT Scout on batteries? (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Tue, 12 Dec 2000 23:14:26 -0600
I'm running a 15 amp automotive blade type 32 volt fuse in the power cord to my Corsair II. Its close enough to the edge that I can blow it occasionally. I figure that's better than being too large a
/archives//html/TenTec/2000-12/msg00194.html (8,903 bytes)

79. [TenTec] Scout on batteries (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Wed, 13 Dec 2000 16:42:24 -0600
Doesn't help to run the regulator wire to the load where running on a battery without a regulator... 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting
/archives//html/TenTec/2000-12/msg00203.html (6,813 bytes)

80. [TenTec] SB-221 and Omni 6+ question (score: 1)
Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer)
Date: Fri, 15 Dec 2000 02:59:28 -0600
Or contact Heath Company at Bentor Harbor Michigan. 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting.com Administrative requests: tentec-REQUEST@cont
/archives//html/TenTec/2000-12/msg00214.html (8,223 bytes)


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