- 1. Topband: Bad tower shunt capacitor (score: 1)
- Author: "James C. Hall, MD" <heartdoc@nwtcc.com>
- Date: Wed, 29 Jan 2014 18:26:39 -0600
- I have an omega matched 120 foot tower and I apparently have a bad vacuum variable capacitor. Upon applying more than about 300 watts, the SWR goes off scale. Tuning it out and trying again, yields t
- /archives//html/Topband/2014-01/msg00332.html (7,227 bytes)
- 2. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "Tom W8JI" <w8ji@w8ji.com>
- Date: Wed, 29 Jan 2014 20:43:29 -0500
- I have an omega matched 120 foot tower and I apparently have a bad vacuum variable capacitor. Upon applying more than about 300 watts, the SWR goes off scale. Tuning it out and trying again, yields t
- /archives//html/Topband/2014-01/msg00334.html (8,106 bytes)
- 3. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "James C. Hall, MD" <heartdoc@nwtcc.com>
- Date: Wed, 29 Jan 2014 20:32:06 -0600
- Thanks Steve: Not bad - I may try that ! :) The question in my mind was if there was an arc outside the caps, why would the SWR change ? Anyway, I may be missing something. I haven't been inside the
- /archives//html/Topband/2014-01/msg00336.html (8,021 bytes)
- 4. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: HAROLD SMITH JR <w0rihps@sbcglobal.net>
- Date: Wed, 29 Jan 2014 19:34:45 -0800 (PST)
- Jamie, The VSWR would change because the arc would change the impedance at the Arc point. From perhaps several hundred or thousand ohms to near Zero during the Arc.. 73, Price W0RI Thanks Steve: No
- /archives//html/Topband/2014-01/msg00339.html (8,480 bytes)
- 5. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: Jon Zaimes AA1K <jz73@verizon.net>
- Date: Thu, 30 Jan 2014 04:21:10 -0500
- Look closely and you may see a hairline crack on the bad one. Also look for other possibilities. A number of times I've swapped out "bad" matching capacitors without solving the problem, only to find
- /archives//html/Topband/2014-01/msg00341.html (8,767 bytes)
- 6. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "Don Beattie" <g3ozf@btinternet.com>
- Date: Thu, 30 Jan 2014 04:26:35 -0500
- Jamie, When I had a problem like that on a matching system, I had someone else key the transmitter and watched the feedpoint at night. It took ten seconds to see the problem ! Fireworks had nothing o
- /archives//html/Topband/2014-01/msg00342.html (8,418 bytes)
- 7. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: Herb Schoenbohm <herbs@vitelcom.net>
- Date: Wed, 29 Jan 2014 23:53:26 -0400
- Wouldn't 1 5/8 hardline make a better HV RF capacitor? Herb, KV4FZ The VSWR would change because the arc would change the impedance at the Arc point. From perhaps several hundred or thousand ohms to
- /archives//html/Topband/2014-01/msg00347.html (9,200 bytes)
- 8. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "James C. Hall, MD" <heartdoc@nwtcc.com>
- Date: Thu, 30 Jan 2014 10:49:06 -0600
- Jon: Thanks for this. This has crossed my mind since I use hose clamps to attach the wire from the top and bottom of the caps. I had used copper flashing between the two caps. I'll change that to a h
- /archives//html/Topband/2014-01/msg00352.html (9,672 bytes)
- 9. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "ZR" <zr@jeremy.mv.com>
- Date: Thu, 30 Jan 2014 11:28:46 -0500
- The 3" line sections will handle more (-; And as many BCB and other commercial stations are being dismantled it is available at scrap prices or less. I have several large rolls of 1 5/8" here for sal
- /archives//html/Topband/2014-02/msg00005.html (9,564 bytes)
- 10. Re: Topband: Bad tower shunt capacitor (score: 1)
- Author: "James C. Hall, MD" <heartdoc@nwtcc.com>
- Date: Sat, 1 Feb 2014 16:31:20 -0600
- Just an update on this - last night FT5ZM was spotted briefly on 160M and I went down to listen for awhile. I didn't hear much and what I did hear I couldn't make myself believe it was them ! So I th
- /archives//html/Topband/2014-02/msg00021.html (11,311 bytes)
This search system is powered by
Namazu