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References: [ +from:prforbes@bigpond.net.au: 34 ]

Total 34 documents matching your query.

1. [Towertalk] re Ferrites and DC (score: 1)
Author: prforbes@bigpond.net.au (Peter Forbes)
Date: Sat, 11 Jan 2003 21:57:40 +1100
Apologies to Steve, as it is not strictly towers or antennas, but may have implications if someone is using a portable power generator on a tower project. Chuck and Rick and others, you may have opin
/archives//html/Towertalk/2003-01/msg00204.html (8,138 bytes)

2. [Towertalk] re Ham IV rotator housing bolts (score: 1)
Author: prforbes@bigpond.net.au (Peter Forbes)
Date: Sun, 1 Dec 2002 00:17:42 +1100
The loosening of these bolts is only a problem if semi-regular maintenance is not done on the rotator. They should be tightened to the correct torque as specified in the owners's manual. The problem
/archives//html/Towertalk/2002-11/msg00808.html (7,223 bytes)

3. [Towertalk] re; Propagation Angles (score: 1)
Author: prforbes@bigpond.net.au (Peter Forbes)
Date: Tue, 25 Jun 2002 17:05:59 +1000
Guy Olinger K2AV asked where the experimental data is. The foillowing is a short list of Journal articles that go some way towards answering your question. Any decent University Library should be hav
/archives//html/Towertalk/2002-06/msg00375.html (10,159 bytes)

4. [Towertalk] re 402BA (score: 1)
Author: prforbes@bigpond.net.au (Peter Forbes)
Date: Sun, 21 Apr 2002 21:14:38 +1000
Wayne N2WK A common fault which develops in the 402BA is a puncture hole through the plastic cap which sits on the driven element centre and insulates from the boom. A carbon track develops and will
/archives//html/Towertalk/2002-04/msg00890.html (6,848 bytes)

5. [TowerTalk] re GROUNDING OF FIELD DAY STATIONS (score: 1)
Author: "Peter Forbes" <prforbes@bigpond.net.au>
Date: Fri, 21 Jan 2005 11:45:42 +1100
Interesting discussion points made by respondents regarding grounding, 3 wire extension leads and use of GFIs. BE AWARE that not all setups can achieve this. IN PARTICULAR, the HONDA series of genera
/archives//html/Towertalk/2005-01/msg00904.html (8,192 bytes)

6. Re: [TowerTalk] w1gkk & big arrays (score: 1)
Author: "Peter Forbes" <prforbes@bigpond.net.au>
Date: Sat, 12 Mar 2005 23:13:19 +1100
Tom's comments. I couldn't agree more. Just one example, which might make some of you northerners take note. The ARRL Challenge Award, you would think is a fair measure of station performance across
/archives//html/Towertalk/2005-03/msg00229.html (9,541 bytes)

7. Re: [TowerTalk] w1gkk & big arrays (score: 1)
Author: "Peter Forbes" <prforbes@bigpond.net.au>
Date: Sat, 12 Mar 2005 23:32:38 +1100
I should have added that YV1DIG is in fact in the northern hemisphere (although we tend to think of all South America as being more closely aligned with the Southern Hemisphere), which makes the figu
/archives//html/Towertalk/2005-03/msg00230.html (10,870 bytes)

8. Re: [TowerTalk] Cage Vertical (score: 1)
Author: "Peter Forbes" <prforbes@bigpond.net.au>
Date: Mon, 18 Jul 2005 20:17:17 +1000
Hi Peter, I have been reading the discussion regarding cages - very interesting. What really interests me is your comment about using a SteppIR as top loading. Currently, I am using a 52 foot free st
/archives//html/Towertalk/2005-07/msg00421.html (12,866 bytes)

9. Re: [TowerTalk] 40 meter vertical ant (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Mon, 12 Feb 2007 17:47:11 +1100
Hi All, Why not rephrase the question slightly and take away the issue of mast support height? You have a 66 foot tree (or wooden mast) from which you can properly hang a vertical dipole. Alternative
/archives//html/Towertalk/2007-02/msg00197.html (9,347 bytes)

10. [TowerTalk] re Trapped Tribanders Turned Vertical (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Thu, 21 Jun 2007 06:31:40 +1000
Hi, Whilst the esoteric discussion on vertical versus horizotal polarisation is interesting, the main focus of the original question seems to have been lost. Mounting a traditional tribander in a ver
/archives//html/Towertalk/2007-06/msg00663.html (8,170 bytes)

11. Re: [TowerTalk] New MF Broadcasting Array (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Thu, 5 Jul 2007 09:24:37 +1000
FWIW, If this station is operating on 1539 Khz, it is quite close to, but above the electron gyro frequency, which is around 1450 Khz in Europe. This brings into effect two issues: (!) the high absor
/archives//html/Towertalk/2007-07/msg00208.html (9,237 bytes)

12. Re: [TowerTalk] help with interference problems (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Wed, 18 Jul 2007 15:14:50 +1000
A suggestion: Perhaps it is time that Jim posted a little expose on the differences between common mode and differential mode, as clearly there are misunderstandings about what CAT5 does and doesn't
/archives//html/Towertalk/2007-07/msg00701.html (9,917 bytes)

13. Re: [TowerTalk] advice sought (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Sun, 21 Oct 2007 13:23:20 +1000
Hi Art. support.. If you run the coax feed down the 20 foot support on insulated standoffs and then put an omega style tuner at the base, the whole antenna will work as a base fed vertical on 80mx as
/archives//html/Towertalk/2007-10/msg00489.html (12,294 bytes)

14. Re: [TowerTalk] Capacitors To Tune 160 Vertical (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Thu, 29 Nov 2007 06:58:30 +1100
Jim, I would be surprised if your 10 - 100nF 400VDC capacitors are capable of taking 6 amps at 1.8 Mhz, without excessive heating and drifting. Therefore your only option is to parallel the 100 to 50
/archives//html/Towertalk/2007-11/msg00527.html (10,068 bytes)

15. Re: [TowerTalk] Capacitors To Tune 160 Vertical (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Fri, 30 Nov 2007 17:15:17 +1100
Hi Jim, Whilst polypropylene dielectric capacitors can be put to good use in RF bypassing circuits, the one point you overlooked is their capacitance shift with temperature. Whilst I have not seen th
/archives//html/Towertalk/2007-11/msg00539.html (14,340 bytes)

16. Re: [TowerTalk] Line Noise (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Fri, 14 Dec 2007 01:10:46 +1100
Dennis, It would have been interesting to look at the pole at night to see if there was any visible arcing between the bracket and the wood. That is one of the first things we do in VK land, since li
/archives//html/Towertalk/2007-12/msg00214.html (13,115 bytes)

17. Re: [TowerTalk] Bandpass Filters (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Thu, 10 Jan 2008 12:20:22 +1100
Alfredo, How much power do you intend running through the bandpass filters? If you are using the newer rigs which can run 200 watts out, then you might have trouble with the Dunestar and ICE filters
/archives//html/Towertalk/2008-01/msg00129.html (8,662 bytes)

18. Re: [TowerTalk] Bandpass Filters (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Thu, 10 Jan 2008 14:47:33 +1100
Absolutely Al, The filters work in two ways: On receive you have minimal receive insertion loss at the frequency it is designed for and deep notches (up to 80dB) on the adjacent bands. On transmit yo
/archives//html/Towertalk/2008-01/msg00134.html (11,961 bytes)

19. Re: [TowerTalk] Fees for Amateur Radio (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Wed, 13 Feb 2008 16:31:50 +1100
Gordon, It is probably inappropriate to be critical of another countries tax regime when you don't have all the facts. In the case of Australian Amateur licensing, which is a subset of Australian App
/archives//html/Towertalk/2008-02/msg00122.html (14,118 bytes)

20. [TowerTalk] re Feeding a long distance array (score: 1)
Author: " Peter Forbes" <prforbes@bigpond.net.au>
Date: Tue, 18 Nov 2008 07:03:56 +1100
Roger, If you can use a heliax type of cable, you are looking at about 0.17 dB per 100 feet of loss (not counting the connectors), so 400 feet (300 + 80 + shack end) will be about 0.7 dB, which will
/archives//html/Towertalk/2008-11/msg00436.html (7,538 bytes)


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