Topband: 160 GP Choke
Thanks to all who responded. One of the suggestions was to wrap about 40-45 turns of RG8X mini on a PVC core with a diameter of 4 incheslightweight and easy. Part two was to ground the braid of the feeder line coax at the point where it reaches ground level. What do you think? Bill K4XS _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 160 meters RFI caused by low voltage bookcase lights
Late last week I encountered interference on 160 meters which was repeating at 41 khz intervals, and this morning I was able to track the problem down to low voltage bookcase lights at my neighbors home which is 430 feet away. I created a website to document this case which includes a link to a youtube video that contains receive audio of the noise, and my simple website URL is http://sites.google.com/site/bookcaselightsrfi/ The signal was S9 on 160 meters (approximately 15 dB above my noise floor when using a 500 hz receive filter), and it could be heard up into the 80 meter band. We (my neighbor and I) will now dig into his low voltage lighting system to see what we can do to eliminate the interference. Just FYI, Don Kirk (wd8dsb) _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 GP Choke
If it were my system, I would use an air core choke like you posted and ground the feedline where it reaches earth. The nice thing is you can install the choke right at ground level with no ill effects at all. Cheap, simple, and clean. It will work as well as anything else you can do and be very reliable. 73 Tom - Original Message - From: Cqtestk4xs--- via Topband topband@contesting.com To: topband@contesting.com Sent: Monday, September 29, 2014 12:49 PM Subject: Topband: 160 GP Choke Thanks to all who responded. One of the suggestions was to wrap about 40-45 turns of RG8X mini on a PVC core with a diameter of 4 incheslightweight and easy. Part two was to ground the braid of the feeder line coax at the point where it reaches ground level. What do you think? Bill K4XS _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4025/8293 - Release Date: 09/29/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 GP Choke
On Mon,9/29/2014 2:31 PM, Mike Waters wrote: It's 6 turns of F-6 coax through four 2.4 OD Fair-rite #31 cores ($7 each from Mouser), per K9YC's PDF. My pdf calls for a lot more turns than that for 160M, but it ain't broke, don't fix it. :) 73, Jim _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 GP Choke
From p. 33: With RG-6, RG-8X, and RG-59, use 7 turns through five 2.4 o.d. #31 toroidal cores. Looks like it could stand one more core and one more turn, if I only used it on 160 and 80. 73, Mike www.w0btu.com On Mon, Sep 29, 2014 at 5:44 PM, Jim Brown j...@audiosystemsgroup.com wrote: On Mon,9/29/2014 2:31 PM, Mike Waters wrote: It's 6 turns of F-6 coax through four 2.4 OD Fair-rite #31 cores ($7 each from Mouser), per K9YC's PDF. My pdf calls for a lot more turns than that for 160M, but it ain't broke, don't fix it. :) 73, Jim _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 GP Choke
W0BTU was kind enough to include a link to his inverted-L EZNEC model so I added that to a thread over on eHam which discusses using a dual-band autopilot matching network, in this case using the inverted-L on 160 and 80 with no tweaking or switching of the matching network needed: http://www.eham.net/ehamforum/smf/index.php/topic,99152.0.html Nothing to do with chokes, just thought it might be of interest. Dan, AC6LA _ Topband Reflector Archives - http://www.contesting.com/_topband
