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Total 1585 documents matching your query.

121. Re: Topband: Best Height Above Ground for a Beverage RX Antenna (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 10 Jan 2007 19:00:18 -0800
On Wed, 10 Jan 2007 18:27:03 -0800, Richard \(Rick\) Karlquist wrote: That's what I would expect. Mine are pretty high (as a fraction of a wavelength) on 40, about right on 160. Jim _________________
/archives//html/Topband/2007-01/msg00201.html (8,893 bytes)

122. Re: Topband: Best Height Above Ground for a Beverage RX Antenna (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 11 Jan 2007 13:25:07 -0800
I had the same concerns. Although my Beverages are not buried, both of them run into the side of a hill, and both cross fairly deep ravines (70 ft or so of down and up in lengths of 500 ft and 600 ft
/archives//html/Topband/2007-01/msg00229.html (10,532 bytes)

123. Re: Topband: Teflon tubing in binocular ferrites (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 18 Jan 2007 09:37:37 -0800
Resistivity varies widely from one ferrite material to another. Some are such good insulators that Fair-Rite uses bare wire to wind coils through them (they call them Wound Beads), while others are h
/archives//html/Topband/2007-01/msg00307.html (7,688 bytes)

124. Re: Topband: 1000m of radials (3280ft), how should I cut it ? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 21 Jan 2007 19:56:18 -0800
The definitive treatment of this is by Rudy Severns, N6LF. He answers EXACTLY your question. It is now part of the ARRL Antenna Book, and this section alone is worth the price of that book plus whate
/archives//html/Topband/2007-01/msg00359.html (8,120 bytes)

125. Re: Topband: arizona report (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 25 Jan 2007 07:47:50 -0800
I'm near Santa Cruz on 8.5 acres with vertical, a dipole, and Beverages (one aimed at EU), and the only signal I've EVER heard from EU is DL2PY. He was there again last night around 9 pm PST, and som
/archives//html/Topband/2007-01/msg00388.html (7,842 bytes)

126. Re: Topband: Key Clicks (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 26 Jan 2007 14:02:18 -0800
One of the obligations that goes with being "a big gun" is keeping the barrel clean. I operated the first night of ARRL 160 with a new Beverage setup (finished that morning) that somehow made my sign
/archives//html/Topband/2007-01/msg00417.html (7,421 bytes)

127. Re: Topband: Feeding a Cell Tower for 160? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 31 Jan 2007 09:54:51 -0800
I have done exactly that at an old AT&T long lines site near Sacramento. It is a loaded half wave that is about 170 ft long, and it DOES work very well. Expect gain on the order of 3 dB in the direct
/archives//html/Topband/2007-01/msg00486.html (7,957 bytes)

128. Re: Topband: RG6 Coax FEED for Beverage ?? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 04 Feb 2007 20:26:01 -0800
The advantage to that particular cable is that it stands up particularly well to the elements (and small rodents). Other than that, there's nothing special about it -- any decent coax with good mecha
/archives//html/Topband/2007-02/msg00028.html (7,795 bytes)

129. Re: Topband: Small lot antenna idea (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 09 Feb 2007 08:46:16 -0800
Study the ARRL Antenna Book on the topic of "Ground." An EARTH connection does NOTHING for an antenna system. What you need is WIRE to return the antenna current, in the form of radials or a counterp
/archives//html/Topband/2007-02/msg00071.html (7,747 bytes)

130. Re: Topband: Beverage question (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 21 Feb 2007 08:08:19 -0800
I would ignore that advice. He's got open fields, and you don't, so use what you have. My two reversible Beverages run through a redwood forest with rather irregular terrain (+/- 75 ft elevation chan
/archives//html/Topband/2007-02/msg00210.html (7,842 bytes)

131. Re: Topband: What do you use as a "Run" antenna? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 27 Feb 2007 08:58:23 -0800
"running" I have two transmit antennas for 160 -- a vertical, and a dipole at 90 ft. The vertical is by far the most effective within a few hours of sunrise or sunset. My default RX is whichever of t
/archives//html/Topband/2007-02/msg00286.html (8,773 bytes)

132. Re: Topband: What do you use as a "Run" antenna? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 28 Feb 2007 09:39:33 -0800
Your explanation is solid on all counts, and I'm sure you're right as far as that goes. BUT: What I'm talking about is different -- the propagation is there, west coast signals ARE above the noise an
/archives//html/Topband/2007-02/msg00299.html (8,862 bytes)

133. Re: Topband: Yaesu FT857D & Separate Rcv Ant (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 06 Mar 2007 12:49:36 -0800
Charles, Rigs like the FT857 are designed for VERY casual use, like something to have in the car and work all bands, or as a first all band rig. They are poor choices for serious hamming (like pullin
/archives//html/Topband/2007-03/msg00030.html (7,830 bytes)

134. Re: Topband: Coax for Beverage feed? (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 07 Mar 2007 09:13:27 -0800
You're right -- virtually any 50 ohm or 75 ohm cable WILL work electrically, so it's simply a matter of finding coax that you can easily buy and that is sufficiently robust to withstand your environe
/archives//html/Topband/2007-03/msg00035.html (6,927 bytes)

135. Re: Topband: Core for K9AY loop transformer (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 27 Mar 2007 10:05:40 -0700
When you use a ferrite to wind a transformer, you want LOW loss. When you use a ferrite for suppression of RFI, you want HIGH loss. The Fair-Rite catalog is listing this as a suppression part, and 25
/archives//html/Topband/2007-03/msg00123.html (7,706 bytes)

136. Re: Topband: Core for K9AY loop transformer (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 28 Mar 2007 16:25:44 -0700
Not true. The loss component is of far greater use. Consider a suppressor on a wire shorter than a quarter wave. The choke and the line are a series circuit, and the line will be capacitive. An indu
/archives//html/Topband/2007-03/msg00147.html (9,428 bytes)

137. Re: Topband: Core for K9AY loop transformer (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 28 Mar 2007 20:17:05 -0700
Not in this case -- the +/- reactance conditions in the first half wavelength illustrates the principle. Of course it repeats, and if you read the tutorial you'll see that. But I'm not teaching trans
/archives//html/Topband/2007-03/msg00150.html (8,484 bytes)

138. Re: Topband: WAJA 160 (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 30 Mar 2007 10:13:41 -0700
It all depends on your objective. If it's bragging rights, verification is important to some people. I play radio for my own enjoyment. Yes, it makes me feel good that my antennas and operating skill
/archives//html/Topband/2007-03/msg00172.html (8,160 bytes)

139. Re: Topband: Protecting RX input & FK8CP this morning (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 04 Apr 2007 07:34:48 -0700
Remi is often fairly loud here in Santa Cruz for more than a few minutes, but it seems that his receive conditions (perhaps QRN) are not nearly as good as his transmitting system. My QTH (5 miles dow
/archives//html/Topband/2007-04/msg00026.html (7,325 bytes)

140. Re: [TowerTalk] Topband: info on radials repartition... (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 13 Apr 2007 09:09:10 -0700
I disagree. Matching is trivial. My concern is the pattern. I would expect to see little change in the lobes, but significant degradation of the nulls. Maybe you don't care about the nulls, but I've
/archives//html/Topband/2007-04/msg00080.html (7,710 bytes)


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