I must have missed something, but shouldn't the ferrites be on the antenna feed line near the antenna and not on the stove?
Mike K4QET -----Original Message----- From: Topband [mailto:[email protected]] On Behalf Of [email protected] Sent: Monday, November 07, 2016 12:00 PM To: [email protected] Subject: Topband Digest, Vol 167, Issue 4 Send Topband mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit http://lists.contesting.com/mailman/listinfo/topband or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of Topband digest..." Today's Topics: 1. Re: RF interference from 160m to GE Electric stove (Bob K6UJ) 2. Re: RF interference from 160m to GE Electric stove ([email protected]) 3. Re: RF interference from 160m to GE Electric stove (Gary Smith) 4. Re: RF interference from 160m to GE Electric stove (Arthur Delibert) 5. Traditional or off-center fed 160m vertical design? (Robert Fanfant) 6. Re: RF interference from 160m to GE Electric stove (Gary Smith) 7. Re: Traditional or off-center fed 160m vertical design? (Herbert Schoenbohm) 8. Re: Traditional or off-center fed 160m vertical design? (Clive GM3POI) 9. Re: Traditional or off-center fed 160m vertical design? (David Cutter) ---------------------------------------------------------------------- Message: 1 Date: Sun, 6 Nov 2016 09:17:41 -0800 From: Bob K6UJ <[email protected]> To: [email protected] Subject: Re: Topband: RF interference from 160m to GE Electric stove Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8; format=flowed Bob, I had to chuckle about your experience on triggering all that stuff in the house. :-) Although not HF band RF interference but I solved an RFI issue on 2 meters with snap on ferrites also. When I keyed up my 50 watt 2 meter xcvr it would activate the garage door opener on the house next door. :-) I probably could have changed the frequency code on his unit but the ferrites worked fine. I don't know the mix just tried a couple of clamp ons I had. Bob K6UJ On 11/6/16 8:20 AM, Bob Lawson N6RW wrote: > Jay > > If you use snap-on ferrites, make sure they are #31 mix. 31 mix is > substantially better than others (like 47 mix) at 160m. When I had a > vertical on the roof at my So Cal house, I would reset my DirecTV HD > receivers, trigger my home security alarm, turn off my air > conditioning fan and so on, when I transmitted on 80 meters. All > problems were solved with 31 mix ferrites. > > 73 de Bob N6RW > > > On 11/6/2016 8:58 AM, Lloyd - N9LB wrote: >> Hello Jay! >> >> Have you tried putting a string of "RF Suppression Snap-On Ferrites" >> on the power cord? >> >> Are the dimensions of the cord such that it is possible to use "RF >> Suppression Snap-On Ferrites"? The largest I could find are .75" >> inside diameter. >> https://www.dxengineering.com/search/part-type/rf-suppression-snap-on-ferrit e-beads >> >> If the power cord for the electric stove is too large, perhaps the >> Snap-On Ferrites could be added to the Romex cable feeding the stove >> outlet if the wiring is accessible, such as in an unfinished basement. >> >> 73 >> >> Lloyd - N9LB >> >> -----Original Message----- >> From: Topband [mailto:[email protected]] On Behalf Of >> [email protected] >> Sent: Sunday, November 06, 2016 9:34 AM >> To: [email protected] >> Subject: Topband: RF interference from 160m to GE Electric stove >> >> Hi guys ? I have recently added a 160m amp to my station and have >> created an RFI problem I can?t solve. >> When I transmit on 160 with any more than 150 watts, the GE electric >> stove in the kitchen ALARMS and must be reset. I guess the 160 signal >> from the vertical is getting into the AC power lines (just a few feet >> away from the AC feed off the pole) and then into the electronics >> into the stove. Reducing the output power to 125 watts or so does not >> cause the problem. Not a permanent condition; hitting the stop button >> on the stove controls stops the stove alarm but starts again when I >> transmit. My XYL HATES alarms?she is a retired ICU RN and I think she >> got conditioned to panic when ANY alarm goes off ! >> Anyhow I wondered if anybody has any similar experience with problems >> like this on 160 and how to solve them. I am tempted to just have an >> electrician come in and install a BIG RF filter on the AC line ? >> either just on the Stove line or to the main feed but I fear this is >> a lot of $$$. I am hesitant to do this one on my own for insurance >> reasons if nothing else. >> Any ideas ? >> Thanx ? Jay NY2NY >> >> >> --- >> This email has been checked for viruses by Avast antivirus software. >> https://www.avast.com/antivirus >> _________________ >> Topband Reflector Archives - http://www.contesting.com/_topband >> >> _________________ >> Topband Reflector Archives - http://www.contesting.com/_topband > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband ------------------------------ Message: 2 Date: Sun, 6 Nov 2016 12:33:24 -0500 From: <[email protected]> To: <[email protected]> Subject: Re: Topband: RF interference from 160m to GE Electric stove Message-ID: <FC564F3D4E3145929473C04B81DD4926@jayPC> Content-Type: text/plain; charset="utf-8" Thanks to all the guys who answered my query ? seems unanimous that I should add Mix 31 Ferrites to the stove ac feed so just ordered them from DX engineering ? shud be installed and tested by the end of the week.. Will probably also add some .05 or so bypass caps to the line while I?m there ? wouldn?t hurt ! tnx again ? keep y?all posted..Jay NY2NY --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------ Message: 3 Date: Sun, 06 Nov 2016 13:36:41 -0500 From: "Gary Smith" <[email protected]> To: [email protected] Subject: Re: Topband: RF interference from 160m to GE Electric stove Message-ID: <[email protected]> Content-Type: text/plain; charset=ISO-8859-1 Another thing that might help if the ferrites don't do the job is to run a wire from a series variable capacitor and variable/tapped inductor, to the stove or possibly to the metal conduit the wires to the stove are going through. This, with an attachment to a counterpoise or ground. My father had problems when he would transmit on 80 and it would trigger the system that used house wiring to turn on various lights in the house when a phone call came in on her line, or the door bell was rung. She was totally deaf and needed this to get to her TTY setup for a voice operator to come in and translate speech to her printout. He did as I described and had a RF ammeter in line. When the capacitor/inductor was adjusted under a key down situation, you could follow the result on the ammeter and at the right setting, the interference stopped triggering the in-line receivers. Sometimes he needed to tweak the setting but it always worked for him. I think MFJ used to have something to do just this, I don't recall what they called it. Good luck & 73, Gary KA1J > Thanks to all the guys who answered my query - seems unanimous that > I should add Mix 31 Ferrites to the stove ac feed so just ordered them > from DX engineering - shud be installed and tested by the end of the > week.. Will probably also add some .05 or so bypass caps to the line > while I?m there - wouldn?t hurt ! > tnx again - keep y?all posted..Jay NY2NY > > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus _________________ Topband Reflector > Archives - http://www.contesting.com/_topband ------------------------------ Message: 4 Date: Sun, 6 Nov 2016 19:12:14 +0000 From: Arthur Delibert <[email protected]> To: "[email protected]" <[email protected]>, "[email protected]" <[email protected]> Subject: Re: Topband: RF interference from 160m to GE Electric stove Message-ID: <bn6pr18mb1314e6e12f4a79c3c92e1253e4...@bn6pr18mb1314.namprd18.prod.outlook. com> Content-Type: text/plain; charset="iso-8859-1" The product that does this is the MFJ Artificial Ground. Costs about $160. Good luck. Art Delibert, KB3FJO ________________________________ From: Topband <[email protected]> on behalf of Gary Smith <[email protected]> Sent: Sunday, November 6, 2016 1:36 PM To: [email protected] Subject: Re: Topband: RF interference from 160m to GE Electric stove Another thing that might help if the ferrites don't do the job is to run a wire from a series variable capacitor and variable/tapped inductor, to the stove or possibly to the metal conduit the wires to the stove are going through. This, with an attachment to a counterpoise or ground. My father had problems when he would transmit on 80 and it would trigger the system that used house wiring to turn on various lights in the house when a phone call came in on her line, or the door bell was rung. She was totally deaf and needed this to get to her TTY setup for a voice operator to come in and translate speech to her printout. He did as I described and had a RF ammeter in line. When the capacitor/inductor was adjusted under a key down situation, you could follow the result on the ammeter and at the right setting, the interference stopped triggering the in-line receivers. Sometimes he needed to tweak the setting but it always worked for him. I think MFJ used to have something to do just this, I don't recall what they called it. Good luck & 73, Gary KA1J > Thanks to all the guys who answered my query - seems unanimous that > I should add Mix 31 Ferrites to the stove ac feed so just ordered them > from DX engineering - shud be installed and tested by the end of the > week.. Will probably also add some .05 or so bypass caps to the line > while I?m there - wouldn?t hurt ! > tnx again - keep y?all posted..Jay NY2NY > > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus _________________ Topband Reflector Avast | Download Free Antivirus for PC, Mac & Android<https://www.avast.com/antivirus> www.avast.com Protect your devices with the best free antivirus on the market. Download Avast antivirus and anti-spyware protection for your PC, Mac and Android. > Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband ------------------------------ Message: 5 Date: Sun, 6 Nov 2016 19:16:45 +0000 From: Robert Fanfant <[email protected]> To: "[email protected]" <[email protected]> Subject: Topband: Traditional or off-center fed 160m vertical design? Message-ID: <by2pr10mb063143fab2401ef73a33ef4fc9...@by2pr10mb0631.namprd10.prod.outlook. com> Content-Type: text/plain; charset="utf-8" I am planning on putting up a 160m T vertical next week. After doing some modeling , I would like your thoughts concerning using a traditional ? vertical design, versus an off center fed design. My modeling of the traditional designs approaches 36-38 ohms of real impedance while the off center fed design shows I can obtain close to 50 ohms of real impedance. Details: Trees on my property are roughly 143? tall and I can?t use ground mounted radials for a variety of reasons. I found I can get up to 110? feet of usable vertical length, assuming radials @ 20? off the ground. The antenna will be suspended between trees. I?ve discovered through modeling using elevated radials at 20? , a 110 vertical section. By varying both the radial and T top section lengths , I can design a 160m vertical which approaches 50 ohms of real impedance , using an off center fed design. It exhibits excellent characteristics from what the modeling shows. Based on the modeling I?m leaning towards the off center fed design primarily because It has a lower SWR at resonance (1.83Mhz) than the traditional vertical, and removes the need for building/adding a matching network if I only want to cover the lower portion of the band (CW). Thoughts? -rob N7QT Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 ------------------------------ Message: 6 Date: Sun, 06 Nov 2016 14:17:54 -0500 From: "Gary Smith" <[email protected]> To: [email protected] Subject: Re: Topband: RF interference from 160m to GE Electric stove Message-ID: <[email protected]> Content-Type: text/plain; charset=ISO-8859-1 I thought I should add some photos of what he made. His was a bit more complex with a transformer and bridge rectifier. Mine was more basic & I used a roller inductor but it did the job. I didn't shrink the photos so as to leave more detail available when you click on a photo. http://doctorgary.net/RFI-1.jpg http://doctorgary.net/RFI-2.jpg http://doctorgary.net/RFI-3.jpg http://doctorgary.net/RFI-4.jpg http://doctorgary.net/RFI-5.jpg 73, Gary KA1J > Another thing that might help if the > ferrites don't do the job is to run a wire > from a series variable capacitor and > variable/tapped inductor, to the stove or > possibly to the metal conduit the wires to > the stove are going through. This, with an > attachment to a counterpoise or ground. > > My father had problems when he would > transmit on 80 and it would trigger the > system that used house wiring to turn on > various lights in the house when a phone > call came in on her line, or the door bell > was rung. She was totally deaf and needed > this to get to her TTY setup for a voice > operator to come in and translate speech > to her printout. > > He did as I described and had a RF ammeter > in line. When the capacitor/inductor was > adjusted under a key down situation, you > could follow the result on the ammeter and > at the right setting, the interference > stopped triggering the in-line receivers. > Sometimes he needed to tweak the setting > but it always worked for him. > > I think MFJ used to have something to do > just this, I don't recall what they called > it. > > Good luck & 73, > > Gary > KA1J > > > Thanks to all the guys who answered my query - seems unanimous that > > I should add Mix 31 Ferrites to the stove ac feed so just ordered > > them from DX engineering - shud be installed and tested by the end > > of the week.. Will probably also add some .05 or so bypass caps to > > the line while I?m there - wouldn?t hurt ! > > tnx again - keep y?all posted..Jay NY2NY > > > > > > --- > > This email has been checked for viruses by Avast antivirus software. > > https://www.avast.com/antivirus _________________ Topband Reflector > > Archives - http://www.contesting.com/_topband > > > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > ------------------------------ Message: 7 Date: Sun, 6 Nov 2016 19:09:42 -0400 From: Herbert Schoenbohm <[email protected]> To: [email protected] Subject: Re: Topband: Traditional or off-center fed 160m vertical design? Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8; format=flowed Not having a balanced "T" top section defeats the whole purpose of reducing the radiation from the top horizontal wire. IMHO the more you can reduce wasted radiation of the cloud warmer effect the better your antenna will perform for DX. Herb, KV4FZ On 11/6/2016 3:16 PM, Robert Fanfant wrote: > Based on the modeling I?m leaning towards the off center fed design primarily because It has a lower SWR at resonance (1.83Mhz) than the traditional vertical, and removes the need for building/adding a matching network if I only want to cover the lower portion of the band (CW). Thoughts? ------------------------------ Message: 8 Date: Mon, 7 Nov 2016 00:10:02 -0000 From: "Clive GM3POI" <[email protected]> To: <[email protected]> Subject: Re: Topband: Traditional or off-center fed 160m vertical design? Message-ID: <[email protected]> Content-Type: text/plain; charset="utf-8" Rob, An off set top loading will radiate unlike a balanced top loading. Far better to eliminate Horizontal radiation unless you want to be louder within a couple of hundred miles. Resonate the vertical at say 1.89, then place a hairpin coil across the feed point to bring the antenna to 1:1 at the wanted operating frequency. Your proposed antenna will need a good feed point choke. 73 Clive GM3POI -----Original Message----- From: Topband [mailto:[email protected]] On Behalf Of Robert Fanfant Sent: 06 November 2016 19:17 To: [email protected] Subject: Topband: Traditional or off-center fed 160m vertical design? I am planning on putting up a 160m T vertical next week. After doing some modeling , I would like your thoughts concerning using a traditional ? vertical design, versus an off center fed design. My modeling of the traditional designs approaches 36-38 ohms of real impedance while the off center fed design shows I can obtain close to 50 ohms of real impedance. Details: Trees on my property are roughly 143? tall and I can?t use ground mounted radials for a variety of reasons. I found I can get up to 110? feet of usable vertical length, assuming radials @ 20? off the ground. The antenna will be suspended between trees. I?ve discovered through modeling using elevated radials at 20? , a 110 vertical section. By varying both the radial and T top section lengths , I can design a 160m vertical which approaches 50 ohms of real impedance , using an off center fed design. It exhibits excellent characteristics from what the modeling shows. Based on the modeling I?m leaning towards the off center fed design primarily because It has a lower SWR at resonance (1.83Mhz) than the traditional vertical, and removes the need for building/adding a matching network if I only want to cover the lower portion of the band (CW). Thoughts? -rob N7QT Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 _________________ Topband Reflector Archives - http://www.contesting.com/_topband ------------------------------ Message: 9 Date: Mon, 7 Nov 2016 14:23:13 -0000 From: "David Cutter" <[email protected]> To: "Robert Fanfant" <[email protected]>, <[email protected]> Subject: Re: Topband: Traditional or off-center fed 160m vertical design? Message-ID: <A93E401FA443426DB4730276BB31403D@DavidPC> Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original Have a look at this idea: http://www.m0rzf.co.uk/ants1/ This is an off centre fed but your normal feeder is connected to the end of the antenna via a choke. I've made several of the 40m version and 3 using double the sizes for 80m. I used simpler chokes for both and measured common mode currents to ensure it worked as an inverted L with no ground radials. This is a variant of the sleeve dipole or "end fed dipole" often used at VHF and above. I and a friend are now making one for 160m but with a different choke and balun suitable for the band. The Ruthroff will be about twice as long and the choke will be on #31 core. Give it some thought; it seems to me you have the facility (height) to make a good one, whereas we are very much restricted in height. My keenness for this idea is that radiation to the ground is minimised because the real feedpoint is several metres in the air at the junction with the Ruthroff. In my case I've arranged the transmitter attachment (end connection) to be at ground level where the choke is grounded to minimise common mode current back to the tx. In my tests on the 80m version, I can reasonably estimate losses at about 5%, most of which is in the choke (a #43 with 16 turns of thin PTFE coax). I used air tests with several precision thermistors and in pure water as a calorimeter test running 100W. With suitable rating core and coax I don't see why it shouldn't run at your legal limit. David G3UNA ----- Original Message ----- From: "Robert Fanfant" <[email protected]> To: <[email protected]> Sent: Sunday, November 06, 2016 7:16 PM Subject: Topband: Traditional or off-center fed 160m vertical design? > > I am planning on putting up a 160m T vertical next week. After doing some > modeling , I would like your thoughts concerning using a traditional ? > vertical design, versus an off center fed design. > > My modeling of the traditional designs approaches 36-38 ohms of real > impedance while the off center fed design shows I can obtain close to 50 > ohms of real impedance. > > Details: > Trees on my property are roughly 143? tall and I can?t use ground > mounted radials for a variety of reasons. I found I can get up to 110? > feet of usable vertical length, assuming radials @ 20? off the ground. > The antenna will be suspended between trees. > > I?ve discovered through modeling using elevated radials at 20? , a 110 > vertical section. By varying both the radial and T top section lengths , > I can design a 160m vertical which approaches 50 ohms of real impedance , > using an off center fed design. It exhibits excellent characteristics from > what the modeling shows. Based on the modeling I?m leaning towards the off > center fed design primarily because It has a lower SWR at resonance > (1.83Mhz) than the traditional vertical, and removes the need for > building/adding a matching network if I only want to cover the lower > portion of the band (CW). Thoughts? > > -rob N7QT > > > > Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows > 10 > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband ------------------------------ Subject: Digest Footer _______________________________________________ Topband mailing list [email protected] http://lists.contesting.com/mailman/listinfo/topband ------------------------------ End of Topband Digest, Vol 167, Issue 4 *************************************** _________________ Topband Reflector Archives - http://www.contesting.com/_topband
