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Total 35 documents matching your query.

1. [TowerTalk] Antenna element vibration damping - How (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Sun Aug 10 05:18:03 2003
Hi all, concerning the vibration I do have experience that vibration is also very dependent on the behavior of the tower. We had an antenna that behaved fine on one tower for years. When moved to oth
/archives//html/Towertalk/2003-08/msg00323.html (14,576 bytes)

2. [TowerTalk] Re: Antenna element vibration damping - How (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Mon Aug 11 07:16:18 2003
Hi Exactly that is it. We have made elements with steep and slow taper. with long and short thick section, light and medium heavy (25-38mm tube in the center of 20m element)......all of them vibrated
/archives//html/Towertalk/2003-08/msg00368.html (12,972 bytes)

3. [TowerTalk] Relays (score: 1)
Author: jirka@jimaz.cz (Jir(í anda)
Date: Tue Feb 25 12:42:35 2003
Hi Mikael, you have two problems: 1. - the smaller one - the relay should handle about 7-10A 2. - THE MUCH bigger one - the relay should also be capable of transfering 0.3 microVolt/50 Ohm - i.e. 0.0
/archives//html/Towertalk/2003-02/msg00469.html (10,290 bytes)

4. [Towertalk] Re: Phasing Lines For Stacks (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Thu, 22 Aug 2002 20:21:10 +0200 (Central Europe Daylight Time)
Hi, the explanation is more simple. On one frequency 1 OR 2 WL would be almost OK, but the band is much wider, the bigger difference in the cables you have the bigger difference in real electrical le
/archives//html/Towertalk/2002-08/msg00656.html (10,200 bytes)

5. [Towertalk] Common-mode choke at 430 Mhz (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Wed, 17 Jul 2002 21:40:38 +0200 (Central Europe Daylight Time)
Hi ! NO ! YES ! Check the SM5BSZand G3SEK sites, there is answer to all questions. P.S. Yes I know about ferrite beads - it. FAR the BEST solution. 73 ! Jiri OK1RI P.S.1 I know also something about V
/archives//html/Towertalk/2002-07/msg00461.html (9,395 bytes)

6. [Towertalk] EZNEC 3.0 question (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Mon, 20 May 2002 08:04:06 +0200
Can someone tell me what is the improvement from YO 6.55 to YO 7.0. Is it already able to model OWA type Yagis - i.e. would it model correctly the close elements ? What impedance you get if you model
/archives//html/Towertalk/2002-05/msg00499.html (9,099 bytes)

7. [Towertalk] Re: EZNEC 3.0 question (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Mon, 20 May 2002 12:14:17 +0200
I do agree, just a remark: EM "pretends" it's engine is a competition to NEC-4, in real life very hardly available to us - the public. What was written on other places - it is in most cases; we hams
/archives//html/Towertalk/2002-05/msg00503.html (10,693 bytes)

8. [Towertalk] Re: YO 7.5 etc. (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Mon, 20 May 2002 23:13:55 +0200
It sounds interesting. I do find the user friendliness of YO 6.55 (I have here) superior over any other similar SW known to me. Also the optimizer works nicely, just it says your ant is for example 5
/archives//html/Towertalk/2002-05/msg00544.html (11,887 bytes)

9. [Towertalk] [Fwd: Re: YO 7.5] (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Tue, 21 May 2002 15:29:36 +0200
Here is my mail with clear intent to spend at least US $100 and even considering to spend maybe US $ 300 (if it is worthwhile) As a matter of fact I have bought and paid for directly to him for the w
/archives//html/Towertalk/2002-05/msg00561.html (7,230 bytes)

10. [Towertalk] Relay Summary (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Thu, 28 Mar 2002 00:55:22 +0100
Hi Arne, I have to strongly disagree on the biggest problem - biggest problem is to have good contact on receive. All the HighPower realys does not guarantee conection below 1mA or even 10mA. Check t
/archives//html/Towertalk/2002-03/msg00726.html (10,851 bytes)

11. [Towertalk] Relays (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Fri, 29 Mar 2002 00:48:11 +0100
Hi Yes those relay contacts are called BIFURCATED. They are - or today better to say - were - used in telephone lines switching systems, because the telephone companies were addressing the same probl
/archives//html/Towertalk/2002-03/msg00745.html (10,444 bytes)

12. [TowerTalk] home brewing short yagis (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Mon, 1 Oct 2001 08:46:32 +0200
It is of course true, BUT to make shorter elements for 6 m ?!?!?!?!? Is ti worth the trouble ?!?!? And less the performance ?!?!?!? 73 ! Jiri OK1RI Dan You check out L.B. Cebik W4RNL web site. He has
/archives//html/Towertalk/2001-10/msg00002.html (10,220 bytes)

13. [TowerTalk] The best stacking distance for long-boom yagis - 0.5 wavelength!! (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Fri, 27 Jul 2001 22:00:03 +0200
Hello all, since I was directly asked I will come with some answer - or my perception of the problem. 1.It is important to answer the question why to stack the antennas. There is a bunch of answers:
/archives//html/Towertalk/2001-07/msg00566.html (11,488 bytes)

14. [TowerTalk] Optimum Stacking Distance (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Fri, 27 Jul 2001 23:40:32 +0200
Hi, Tom of course theoretically you are right but in the real life and real practical situations the longer boom you have the wider spacing for maximum gain is needed. (OK various nulls and lobes are
/archives//html/Towertalk/2001-07/msg00569.html (11,890 bytes)

15. [TowerTalk] RE: TowerTalk] The best stacking distance for long-boom yagis - 0.5 wavelength!! (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Sat, 28 Jul 2001 08:55:09 +0200
Hi John +others, This was an exceptional situation, we run most of the time both the antennas and usually the difference is below 1-2 S units. This was what "might also happen" 73 ! Jiri -- FAQ on WW
/archives//html/Towertalk/2001-07/msg00594.html (7,140 bytes)

16. [TowerTalk] The best stacking distance for long-boom yagis - 0.5 wavelength!! (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Sat, 28 Jul 2001 12:41:55 +0200
Hi Tono, Concerning vertical stacking of OWA or other Yagi - there is no practical worth mentioning difference on HF. There is a significant difference while stacking various LONG VHF Yagis for EME o
/archives//html/Towertalk/2001-07/msg00600.html (8,953 bytes)

17. [TowerTalk] Vertical top-loading questions (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Wed, 13 Jun 2001 23:23:20 +0200
Hello, read very nice article from L.B.Cebik at his www.cebik.com Name of the proper article is if I remember well "where is my hat or similar. 73 ! Jiri OK1RI --Original Message-- From: owner-towert
/archives//html/Towertalk/2001-06/msg00329.html (9,738 bytes)

18. [TowerTalk] MFJ 259B analyzer vs Autek? (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Fri, 15 Jun 2001 00:14:38 +0200
Hello everyone ! I will come with my opinion. I own AUTEK (over 5 years now, someone wants to buy it ?) + MFJ269 (about 1+1/2 year) + TESLA Laboratory ADMITTANCE bridge - precision device over 25Year
/archives//html/Towertalk/2001-06/msg00362.html (9,026 bytes)

19. [TowerTalk] MFJ 259B vs Autek?, Correction (score: 1)
Author: jirka@jimaz.cz (Jiri Sanda)
Date: Fri, 15 Jun 2001 15:21:52 +0200
Hi, 1.go out and buy some NiCd or NiMh AA cells and all you need is to charge the unit. The cost in some not very long period of time will be lover. It will last charged about 2 hours. The tiny 9V ba
/archives//html/Towertalk/2001-06/msg00379.html (9,530 bytes)

20. [TowerTalk] Connectors (score: 1)
Author: jirka@jimaz.cz (Ji anda)
Date: Tue, 3 Apr 2001 01:37:27 +0200
Hi I do agree with Tom here. Acording to my experience the most important point in quality of the connector is the quality of the female part of it. If the male of UHF goes into the female firmly the
/archives//html/Towertalk/2001-04/msg00040.html (10,768 bytes)


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