Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Does Holy Water increase ground conductivity? Sorry my Catholic brethren, I couldn't help myself. Bill AD5OL - Original Message From: Frank Brickle <[EMAIL PROTECTED]> To: philip gentile <[EMAIL PROTECTED]> Cc: flexradio@flex-radio.biz; root [knesbitt] <[EMAIL PROTECTED]> Sent: Monday, September 11, 2006 12:55:51 PM Subject: Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem On Mon, 2006-09-11 at 13:44 -0400, philip gentile wrote: > after you call the priest, add a length of copper wire at one point to see > if shifting the resonant frequency o fthe pipe helps. Given the price of copper these days, it's probably cheaper just to hire the Pope directly. 73 Frank AB2KT ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/2ca361b4/attachment.html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Jerry, Do you have a pump or electric valve on that water line? On 9/11/06, Tim Ellison <[EMAIL PROTECTED]> wrote: > I got one for you that goes to show everything does have a fundamental > resonant frequency. > > I had recently purchased an Icom AH-4 antenna coupler and was trying out > antenna configurations. I had never used a tuner or coupler before, but > I "thought" I knew what I was doing (NOT!). I decided to mount the AH-4 > under an eve on the end of the house and run a long wire out to one of > the trees in the back yard. So far, so good. Since the antenna coupler > was about 16 feet off the ground and it needed a connection to ground, I > ran a 1" ground strap to the earth and terminated it with a ground rod, > since that is what the instructions "told" me to do. Being extra smart, > I tied this ground rod to the A/C service ground as per the NEC. > > Now, remember that 16' long ground strap? Ok, now what is the length of > a wire that is 1/4 wavelength on 20 meters? About 16'. So, I crank > this puppy up with 100 watts and I am now effectively transmitting a 20 > meter signal into the ground of my house wiring. The one device that > REALLY didn't like this was my powered subwoofer for the Home Theater > that started feeding back at the EXACT resonant audio frequency of the > metal chimney connected to the fireplace insert. It REALLY starts > oscillating since I have magically "found" its fundamental resonant > frequency. It made the loudest noise; sounding like the walls were being > drummed on by some giant Org. The dogs went crazy. The XYL is running > through the house screaming, thinking that a tornado is hitting the > house. > > Now I'm at the other end of the house, the shack door closed, headphones > on making QSOs as fast as I can with Europe using my new antenna. I > can't hear a thing going on in the far end of the house. The shack door > bursts open, which does get my attention and in flies 2 dogs and a XYL > totally freaking out! Needless to say it was easy to find the root of > the problem and I decided that I needed a little more fundamental > knowledge about what a "real" RF ground is and why balanced antennas a > really good things. The fireplace was grateful too. > > > -Tim > --- > Integrated Technical Services > > "Too much of everything is just enough." > -Rob Barlow > > -----Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Mike Naruta > Sent: Monday, September 11, 2006 7:53 PM > To: Allen Boehm; FlexRadio@flex-radio.biz > Subject: Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem > > Yep, it was an interesting demonstration on Mythbusters. > > > Too bad Jerry changed it. I'm guessing that it would not have vibrated > with just carrier. > > > Mike - AA8K > > > Allen Boehm wrote: > > It is not an urban legend. Every thing has a resonate frequency. If > > you dig back into the history of Nikolai Tesla and his earthquake > > machine. Here are two related patents registered by Tesla: Patent No. > > 511,916 (Jan. 2, 1894) titled "Electric Generator" and Patent No. > > 514,169 (Feb. 6, 1894) titled "Reciprocating Engine". > > Al > > > > ___ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Homepage: http://www.flex-radio.com > > ___ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Homepage: http://www.flex-radio.com > -- "There is nothing more uncommon than common sense." -- Frank Lloyd Wright ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
I got one for you that goes to show everything does have a fundamental resonant frequency. I had recently purchased an Icom AH-4 antenna coupler and was trying out antenna configurations. I had never used a tuner or coupler before, but I "thought" I knew what I was doing (NOT!). I decided to mount the AH-4 under an eve on the end of the house and run a long wire out to one of the trees in the back yard. So far, so good. Since the antenna coupler was about 16 feet off the ground and it needed a connection to ground, I ran a 1" ground strap to the earth and terminated it with a ground rod, since that is what the instructions "told" me to do. Being extra smart, I tied this ground rod to the A/C service ground as per the NEC. Now, remember that 16' long ground strap? Ok, now what is the length of a wire that is 1/4 wavelength on 20 meters? About 16'. So, I crank this puppy up with 100 watts and I am now effectively transmitting a 20 meter signal into the ground of my house wiring. The one device that REALLY didn't like this was my powered subwoofer for the Home Theater that started feeding back at the EXACT resonant audio frequency of the metal chimney connected to the fireplace insert. It REALLY starts oscillating since I have magically "found" its fundamental resonant frequency. It made the loudest noise; sounding like the walls were being drummed on by some giant Org. The dogs went crazy. The XYL is running through the house screaming, thinking that a tornado is hitting the house. Now I'm at the other end of the house, the shack door closed, headphones on making QSOs as fast as I can with Europe using my new antenna. I can't hear a thing going on in the far end of the house. The shack door bursts open, which does get my attention and in flies 2 dogs and a XYL totally freaking out! Needless to say it was easy to find the root of the problem and I decided that I needed a little more fundamental knowledge about what a "real" RF ground is and why balanced antennas a really good things. The fireplace was grateful too. -Tim --- Integrated Technical Services "Too much of everything is just enough." -Rob Barlow -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Naruta Sent: Monday, September 11, 2006 7:53 PM To: Allen Boehm; FlexRadio@flex-radio.biz Subject: Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem Yep, it was an interesting demonstration on Mythbusters. Too bad Jerry changed it. I'm guessing that it would not have vibrated with just carrier. Mike - AA8K Allen Boehm wrote: > It is not an urban legend. Every thing has a resonate frequency. If > you dig back into the history of Nikolai Tesla and his earthquake > machine. Here are two related patents registered by Tesla: Patent No. > 511,916 (Jan. 2, 1894) titled "Electric Generator" and Patent No. > 514,169 (Feb. 6, 1894) titled "Reciprocating Engine". > Al > ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Yep, it was an interesting demonstration on Mythbusters. Too bad Jerry changed it. I'm guessing that it would not have vibrated with just carrier. Mike - AA8K Allen Boehm wrote: > It is not an urban legend. Every thing has a resonate frequency. If you dig > back into the history of Nikolai Tesla and his earthquake machine. Here are > two related patents registered by Tesla: Patent No. 511,916 (Jan. 2, 1894) > titled "Electric Generator" and Patent No. 514,169 (Feb. 6, 1894) titled > "Reciprocating Engine". > Al > ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
It is not an urban legend. Every thing has a resonate frequency. If you dig back into the history of Nikolai Tesla and his earthquake machine. Here are two related patents registered by Tesla: Patent No. 511,916 (Jan. 2, 1894) titled "Electric Generator" and Patent No. 514,169 (Feb. 6, 1894) titled "Reciprocating Engine". Al On 9/11/06 3:56 PM, "EB4APL" <[EMAIL PROTECTED]> wrote: > Gerald Capodieci escribió: >> I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. >> At midnight my wife and son came into the room while I was transmitting on >> 3.9000 MHz stating that someone or thing is under the house hitting the >> pipes or dragging chains. My son and I, carrying shovels, walked the >> perimeter to find all the vents and crawl space covers in place. I went to >> the shack to resume transmitting while my son listened. He came in to say the >> water pipes were vibrating. I had him transmit while I looked and I could see >> the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm >> planning on clamping the pipes to the framing but wonder if that solution >> could lead to further problems. Has anyone had similar experience or >> information on this issue? I live near Los Angeles and have great signal >> reports from all the Western states. I'm running resonant inverted Vs with >> nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an >> AL-82 with at >> least 1K Watts out and each piece of equipment is grounded to a 3/4 inch >> copper pipe running through the shack and leading to the copper water pipes >> 30 feet away. I have no TVI, RFI just WPI. >> Jerry >> -- next part -- >> An HTML attachment was scrubbed... >> URL: >> /pipermail/flexradio_flex-radio.biz/attachments/20060911/7f926e54/attachment. >> html >> ___ >> FlexRadio mailing list >> FlexRadio@flex-radio.biz >> http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz >> Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ >> FlexRadio Homepage: http://www.flex-radio.com >> >> > Gerald, > I believe you 100%, but you must admit that this case is a good > candidate for the best "urban legend" in the radio field in years. > No joke, I would like to know how you fix it and a credible > explanation. Antennas resonate (usually) but (usually also) they don´t > vibrate mecanically that way. ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Gerald Capodieci escribió: > I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. > At midnight my wife and son came into the room while I was transmitting on > 3.9000 MHz stating that someone or thing is under the house hitting the > pipes or dragging chains. My son and I, carrying shovels, walked the > perimeter to find all the vents and crawl space covers in place. I went to > the shack to resume transmitting while my son listened. He came in to say the > water pipes were vibrating. I had him transmit while I looked and I could see > the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm > planning on clamping the pipes to the framing but wonder if that solution > could lead to further problems. Has anyone had similar experience or > information on this issue? I live near Los Angeles and have great signal > reports from all the Western states. I'm running resonant inverted Vs with > nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an > AL-82 with at > least 1K Watts out and each piece of equipment is grounded to a 3/4 inch > copper pipe running through the shack and leading to the copper water pipes > 30 feet away. I have no TVI, RFI just WPI. > Jerry > -- next part -- > An HTML attachment was scrubbed... > URL: > /pipermail/flexradio_flex-radio.biz/attachments/20060911/7f926e54/attachment.html > > ___ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Homepage: http://www.flex-radio.com > > Gerald, I believe you 100%, but you must admit that this case is a good candidate for the best "urban legend" in the radio field in years. No joke, I would like to know how you fix it and a credible explanation. Antennas resonate (usually) but (usually also) they don´t vibrate mecanically that way. -- 73 de Ignacio, EB4APL ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Thanks Mike: Grounding the end in the backyard did most of it. I'll get a proper ground rod installed. I only hammered a 3 foot pipe in and made sure the spot was well watered. The pipes still move a little but do not vibrate much. Jerry, kd6et Mike Naruta <[EMAIL PROTECTED]> wrote: Gerald Capodieci wrote: > I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. > At midnight my wife and son came into the room while I was transmitting on > 3.9000 MHz stating that someone or thing is under the house hitting the pipes > or dragging chains. My son and I, carrying shovels, walked the perimeter to > find all the vents and crawl space covers in place. I went to the shack to > resume transmitting while my son listened. He came in to say the water pipes > were vibrating. I had him transmit while I looked and I could see the 3/4 > inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm > planning on clamping the pipes to the framing but wonder if that solution > could lead to further problems. Has anyone had similar experience or > information on this issue? I live near Los Angeles and have great signal > reports from all the Western states. I'm running resonant inverted Vs with > nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an > AL-82 with at > least 1K Watts out and each piece of equipment is grounded to a 3/4 inch > copper pipe running through the shack and leading to the copper water pipes > 30 feet away. I have no TVI, RFI just WPI. > Jerry Hi Jerry, WPI happens much more frequently with Software Defined Radios than with conventional transmitters. We will have a WPI Flooring Filter in an upcoming version that you can download via the SVN. The sampling artifacts induce the vibrations. Interestingly, Lower Side Band seems to affect cold water pipes more frequently and Upper Side Band vibrates the hot water pipes. There was an issue with spread-spectrum and sewer pipes, but that was fixed as soon as it showed up. In the meantime, while you are transmitting, open a faucet in the house a slight amount so that you have drips. Drip size does not matter, but the number of drips per second (DPS) should be an integral multiple of the frequency you are on in Megahertz. Sorry, fellows, I couldn't resist. :) It would appear that the pipe is carrying current, and the magnetic field is attracting something nearby, perhaps an Iron girder? I am trying to imagine the mechanism. If it is the RF, how does 3.9 Mhz resonate at such a low mechanical frequency? Perhaps it is the modulation that is stimulating the pipe. An interesting experiment would be to just transmit a carrier without modulation to see if the pipe will still vibrate. You have, perhaps, the first Water Pipe Detector (WPD) in existence. The data rate is quite slow, but still a unique apparatus. The half-inch deflection of the pipe should be well withing the elastic limit of the pipe. You would only need to worry about fatigue. It sounds as if the pipe is unsupported for a distance. Is this true? Usually plumbing code has it strapped every n inches. If you do fasten the pipe, remember to allow the pipe to slip for expansion and contraction from temperature changes. Mike - AA8K -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/85db423d/attachment.html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
I would add an additional ground (in the ground) directly at the point where it drops under the house if you can manage to do that with a ground rod, however it may be just as well to use only the ground rod and remove the pipe from the equation altogether and see what happens. Someone else mentioned throwing it off resonance on 75m by adding some additional braid or heavy wire to the pipe, and that would possibly be a nice quick fix to try first! On 9/11/06, Frank Brickle <[EMAIL PROTECTED]> wrote: > On Mon, 2006-09-11 at 13:44 -0400, philip gentile wrote: > > after you call the priest, add a length of copper wire at one point to see > > if shifting the resonant frequency o fthe pipe helps. > > Given the price of copper these days, it's probably cheaper just to hire > the Pope directly. > > 73 > Frank > AB2KT > > > ___ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Homepage: http://www.flex-radio.com > -- "There is nothing more uncommon than common sense." -- Frank Lloyd Wright ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
On Mon, 2006-09-11 at 13:44 -0400, philip gentile wrote: > after you call the priest, add a length of copper wire at one point to see > if shifting the resonant frequency o fthe pipe helps. Given the price of copper these days, it's probably cheaper just to hire the Pope directly. 73 Frank AB2KT ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Years ago I had a similar problem on 75 M AM phone. My neighbors could hear me in their bath tub. Bob In a message dated 9/11/2006 12:36:08 P.M. Eastern Daylight Time, [EMAIL PROTECTED] writes: Gerry, it appears that your pipes may be resonate on 75 M. try grounding them at different points. John P. Basilotto W5GI Marketing and Product Manager FlexRadio Systems Office 512-250-8595 Mobile 512-663-6727 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Gerald Capodieci Sent: Monday, September 11, 2006 11:20 AM To: flexradio@flex-radio.biz Subject: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. At midnight my wife and son came into the room while I was transmitting on 3.9000 MHz stating that someone or thing is under the house hitting the pipes or dragging chains. My son and I, carrying shovels, walked the perimeter to find all the vents and crawl space covers in place. I went to the shack to resume transmitting while my son listened. He came in to say the water pipes were vibrating. I had him transmit while I looked and I could see the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm planning on clamping the pipes to the framing but wonder if that solution could lead to further problems. Has anyone had similar experience or information on this issue? I live near Los Angeles and have great signal reports from all the Western states. I'm running resonant inverted Vs with nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an AL-82 with at least 1K Watts out and each piece of equipment is grounded to a 3/4 inch copper pipe running through the shack and leading to the copper water pipes 30 feet away. I have no TVI, RFI just WPI. Jerry -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/7f926e54/attachment .html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/76ce3223/attachment.html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
after you call the priest, add a length of copper wire at one point to see if shifting the resonant frequency o fthe pipe helps. - Original Message - From: "root [knesbitt]" <[EMAIL PROTECTED]> To: Sent: Monday, September 11, 2006 2:39 PM Subject: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem > Jerry, > I would suggest you call a priest immediately. This has nothing to do > with the electrical length of your pipe.. > See: http://www.stmichael.pair.com/ as a starting point > > Cheers, > > Kirb - VE6IV > > -- > > > ___ > FlexRadio mailing list > FlexRadio@flex-radio.biz > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
[Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Jerry, I would suggest you call a priest immediately. This has nothing to do with the electrical length of your pipe.. See: http://www.stmichael.pair.com/ as a starting point Cheers, Kirb - VE6IV -- ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Gerald Capodieci wrote: > I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. > At midnight my wife and son came into the room while I was transmitting on > 3.9000 MHz stating that someone or thing is under the house hitting the > pipes or dragging chains. My son and I, carrying shovels, walked the > perimeter to find all the vents and crawl space covers in place. I went to > the shack to resume transmitting while my son listened. He came in to say the > water pipes were vibrating. I had him transmit while I looked and I could see > the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm > planning on clamping the pipes to the framing but wonder if that solution > could lead to further problems. Has anyone had similar experience or > information on this issue? I live near Los Angeles and have great signal > reports from all the Western states. I'm running resonant inverted Vs with > nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an > AL-82 with at > least 1K Watts out and each piece of equipment is grounded to a 3/4 inch > copper pipe running through the shack and leading to the copper water pipes > 30 feet away. I have no TVI, RFI just WPI. > Jerry Hi Jerry, WPI happens much more frequently with Software Defined Radios than with conventional transmitters. We will have a WPI Flooring Filter in an upcoming version that you can download via the SVN. The sampling artifacts induce the vibrations. Interestingly, Lower Side Band seems to affect cold water pipes more frequently and Upper Side Band vibrates the hot water pipes. There was an issue with spread-spectrum and sewer pipes, but that was fixed as soon as it showed up. In the meantime, while you are transmitting, open a faucet in the house a slight amount so that you have drips. Drip size does not matter, but the number of drips per second (DPS) should be an integral multiple of the frequency you are on in Megahertz. Sorry, fellows, I couldn't resist. :) It would appear that the pipe is carrying current, and the magnetic field is attracting something nearby, perhaps an Iron girder? I am trying to imagine the mechanism. If it is the RF, how does 3.9 Mhz resonate at such a low mechanical frequency? Perhaps it is the modulation that is stimulating the pipe. An interesting experiment would be to just transmit a carrier without modulation to see if the pipe will still vibrate. You have, perhaps, the first Water Pipe Detector (WPD) in existence. The data rate is quite slow, but still a unique apparatus. The half-inch deflection of the pipe should be well withing the elastic limit of the pipe. You would only need to worry about fatigue. It sounds as if the pipe is unsupported for a distance. Is this true? Usually plumbing code has it strapped every n inches. If you do fasten the pipe, remember to allow the pipe to slip for expansion and contraction from temperature changes. Mike - AA8K ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
[Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Zounds! Could it be audio resonance some where? It would take a lot of current to move a 1/2" pipe, then again if its hanging free for a long distance--. Let us know what happens to your sig after clamping the pipe. (my xyl once drew an arc of the bathroom light) W8XO ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
Gerry, it appears that your pipes may be resonate on 75 M. try grounding them at different points. John P. Basilotto W5GI Marketing and Product Manager FlexRadio Systems Office 512-250-8595 Mobile 512-663-6727 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Gerald Capodieci Sent: Monday, September 11, 2006 11:20 AM To: flexradio@flex-radio.biz Subject: [Flexradio] SDR1000 WPI (Water Pipe Interference) Problem I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. At midnight my wife and son came into the room while I was transmitting on 3.9000 MHz stating that someone or thing is under the house hitting the pipes or dragging chains. My son and I, carrying shovels, walked the perimeter to find all the vents and crawl space covers in place. I went to the shack to resume transmitting while my son listened. He came in to say the water pipes were vibrating. I had him transmit while I looked and I could see the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm planning on clamping the pipes to the framing but wonder if that solution could lead to further problems. Has anyone had similar experience or information on this issue? I live near Los Angeles and have great signal reports from all the Western states. I'm running resonant inverted Vs with nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an AL-82 with at least 1K Watts out and each piece of equipment is grounded to a 3/4 inch copper pipe running through the shack and leading to the copper water pipes 30 feet away. I have no TVI, RFI just WPI. Jerry -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/7f926e54/attachment .html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
[Flexradio] SDR1000 WPI (Water Pipe Interference) Problem
I need advice or a lead on Water Pipe Interference (WPI). This is not a joke. At midnight my wife and son came into the room while I was transmitting on 3.9000 MHz stating that someone or thing is under the house hitting the pipes or dragging chains. My son and I, carrying shovels, walked the perimeter to find all the vents and crawl space covers in place. I went to the shack to resume transmitting while my son listened. He came in to say the water pipes were vibrating. I had him transmit while I looked and I could see the 3/4 inch water pipe moving rapidly back and forth in 1/2 inch cycles. I'm planning on clamping the pipes to the framing but wonder if that solution could lead to further problems. Has anyone had similar experience or information on this issue? I live near Los Angeles and have great signal reports from all the Western states. I'm running resonant inverted Vs with nearly a 1:1 match fed through a balun and RG213. The SDR1000 is driving an AL-82 with at least 1K Watts out and each piece of equipment is grounded to a 3/4 inch copper pipe running through the shack and leading to the copper water pipes 30 feet away. I have no TVI, RFI just WPI. Jerry -- next part -- An HTML attachment was scrubbed... URL: /pipermail/flexradio_flex-radio.biz/attachments/20060911/7f926e54/attachment.html ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
