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Inline Isolators for RFI reduction ?
Question to those who may have used one - Do inline isolators work
well on RX? Such as those sold by Radioworks? Thanks, Bruce Jensen |
Inline Isolators for RFI reduction ?
On 01/16/2011 11:24 AM, bpnjensen wrote:
Question to those who may have used one - Do inline isolators work well on RX? Such as those sold by Radioworks? Thanks, Bruce Jensen That is complete overkill for receive only. These are great folks. Whether you buy a half dozen or a pallet, they treat you right. http://www.minicircuits.com/cgi-bin/...rch_type=model |
Inline Isolators for RFI reduction ?
On 1/16/2011 11:24 AM, bpnjensen wrote:
Question to those who may have used one - Do inline isolators work well on RX? Such as those sold by Radioworks? Thanks, Bruce Jensen Yes, amateurs have been rolling their own for a long time, most often referred to as "traps" on an amateur antenna. Allows operation over multiple bands when wire lengths are cut and tuned correctly ... Regards, JS |
Inline Isolators for RFI reduction ?
On Jan 16, 11:24*am, bpnjensen wrote:
Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and "Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook = http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . . http://groups.google.com/group/rec.r...5cc467b35a70d5 |
Inline Isolators for RFI reduction ?
On Jan 16, 1:34*pm, RHF wrote:
On Jan 16, 11:24*am, bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and *"Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 *. *. Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. |
Inline Isolators for RFI reduction ?
On Jan 16, 12:00*pm, dave wrote:
On 01/16/2011 11:24 AM, bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen That is complete overkill for receive only. These are great folks. Whether you buy a half dozen or a pallet, they treat you right. http://www.minicircuits.com/cgi-bin/...1.18-3-X65%2B&.... Thanks, Dave, but I am afraid I don't even know what these devices are or how they'd be used. |
Inline Isolators for RFI reduction ?
On Jan 16, 1:34*pm, RHF wrote:
On Jan 16, 11:24*am, bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and *"Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 *. *. Thanks - I see the Wellbrook diagrams. Believe me, If I had the space, that's how I'd do it. I have a tiny lot with the house plopped right in the center, power lines fore and aft and neighbors by the bushel within a hundred feet. My wire, by necessity, must go over my rooftop. In all other respects, it is built roughly as you see in the "good" diagram. The isolator is a last resort. |
Inline Isolators for RFI reduction ?
On 1/16/2011 5:08 PM, bpnjensen wrote:
... Thanks, Dave, but I am afraid I don't even know what these devices are or how they'd be used. This might help: http://www.iw5edi.com/ham-radio/?how...-traps-work,88 Regards, JS |
Inline Isolators for RFI reduction ?
On 01/16/2011 05:07 PM, bpnjensen wrote:
On Jan 16, 1:34 pm, wrote: On Jan 16, 11:24 am, wrote: Question to those who may have used one - Do inline isolators work well on RX? Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and "Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 . . Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You gotta build a loop. |
Inline Isolators for RFI reduction ?
On 01/16/2011 05:17 PM, John Smith wrote:
On 1/16/2011 5:08 PM, bpnjensen wrote: ... Thanks, Dave, but I am afraid I don't even know what these devices are or how they'd be used. This might help: http://www.iw5edi.com/ham-radio/?how...-traps-work,88 Regards, JS A tuned loop will give you a fighting chance. I think Ace's bud in Chitown has one. Peter somebody... |
Inline Isolators for RFI reduction ?
On 1/16/2011 5:07 PM, bpnjensen wrote:
... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. A GOOD GROUND on the receiver will serve you well. If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS |
Inline Isolators for RFI reduction ?
On Jan 16, 5:17*pm, John Smith wrote:
On 1/16/2011 5:08 PM, bpnjensen wrote: ... Thanks, Dave, but I am afraid I don't even know what these devices are or how they'd be used. This might help:http://www.iw5edi.com/ham-radio/?how...-traps-work,88 Regards, JS Sorry - I know what a trap is - but the thingies Dave linked to do not look like anything in my experience. |
Inline Isolators for RFI reduction ?
On Jan 16, 5:45*pm, dave wrote:
On 01/16/2011 05:07 PM, bpnjensen wrote: On Jan 16, 1:34 pm, *wrote: On Jan 16, 11:24 am, *wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and *"Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 * . * . Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You gotta build a loop. Maybe so. Know of any good plans for something that will fit on a pinhead? |
Inline Isolators for RFI reduction ?
On Jan 16, 6:09*pm, John Smith wrote:
On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. That's no joke. Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here. |
Inline Isolators for RFI reduction ?
On Jan 16, 5:14*pm, bpnjensen wrote:
On Jan 16, 1:34*pm, RHF wrote: On Jan 16, 11:24*am, bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and *"Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 *. *. - Thanks - I see the Wellbrook diagrams. *Believe me, If I had the - space, that's how I'd do it. *I have a tiny lot with the house plopped - right in the center, power lines fore and aft and neighbors by the - bushel within a hundred feet. *My wire, by necessity, must go over my - rooftop. *In all other respects, it is built roughly as you see in the - "good" diagram. - - The isolator is a last resort. BpnJ, -alternative- Isolator 1:1 [UnUn] Matching Transformer Wellbrook Antenna Feeder Isolator AFI 5030 http://www.wellbrook.uk.com/pdf/AFI5030A.pdf http://www.wellbrook.uk.com/antennas...&product_id=56 BpnJ, -alternative-loop-antenna-set-up- Shortwave Listener [SWL] Loop Antenna with : * Four Corners at/near the Lot Line; Centered around the House. * 21 Feet Long/Tall Top-Rail for the Four Corners * Loop Antenna around the Four Corners * Feed-in-Line from one of the Corners to the House a few inches under-the-ground. * Ground each of the pieces of Top-Rail and place a Ground Rod at the Corner where the Feed-in-Line comes in from. * Matching Transformer [MT] -either- * * MT Up-in-the-Air at the Top of the Top-Rail * * MT On-the-Ground with 300 Ohm Twin-Lead from the Loop Antenna Element down to the MT. The Wire Loop Antenna Element should be 5 Foot or more out and away from the House/Roof and help to reduce the Noise Pick-Up from the House itself. * 5 Foot is good * * 10 Foot is Better {Twice as Good} * * * * 20 Foot is GREAT {Four Times as Good} BpnJ, TEST : Your Present SWL Antenna when everyone is away from the House for and overnight. * Run your Radio/Receiver(s) on Batteries. * Turn-Off your AC Mains : This Kills all AC Power to the House -and- Kills all RFI coming from all those Electrical-Electronic 'Gadgets' in the House. * Listen to your Radio Overnight and see what you can hear {RF Signals} and what you can not hear {RF Noise}. All the other RF Noise is assumed to be coming from your Next-Door Neighbors and your nearby Neighborhood [One Block Around You]. * See 'if' you can pin-point any of these RF Noise Sources coming from a specific Next-Door Neighbor. |
Inline Isolators for RFI reduction ?
On Jan 16, 10:13*pm, bpnjensen wrote:
On Jan 16, 6:09*pm, John Smith wrote: On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source.. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. *That's no joke. *Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here.- Hide quoted text - - Show quoted text - Have you attempted to see if it is coming from the ac 120v outlets? Quite often THAT is one the biggest source of noise . What receiver(s) /antenna(s) are you using ? |
Inline Isolators for RFI reduction ?
On Jan 16, 8:27*pm, wrote:
On Jan 16, 10:13*pm, bpnjensen wrote: On Jan 16, 6:09*pm, John Smith wrote: On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. *That's no joke. *Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here.- Hide quoted text - - Show quoted text - Have you attempted to see if it is coming from the ac 120v outlets? Quite often THAT is one the biggest source of noise . *What receiver(s) /antenna(s) are you using ? Actually, I know that my outlets/switch boxes are sources of buzzing RF noise. When I bring an AM radio, especially one with a tunable loop on it, toward the switches and outlets, the buzzing becomes more audible. I believe that the house is miswired so that ground and one hot side may be on the same path (this needs to be fixed). I do have an RF-born noise filter that I run the 115 VAC through. I do not get any serious amount of noise from this source (as far as I can tell) on the radio. The radio I use primarily is an Icom R75 (also an Allied SX-190 and Realistic DX-160). Two external antennas - the random wire with 9:1 match, and a DX-Ultra (essentially an all- band dipole, but pretty worthyless on the tropical bands). The worst noise, by far, is on the lower bands (7 MHz and down). At 15 MHz and above, the noise is typically minimal and reception is quite good. The tropical bands are a mess, with an S-7/S-9 noise level most of the time. I can clean up some of it with my MFJ-1026, but not all. |
Inline Isolators for RFI reduction ?
On 1/16/2011 9:41 PM, bpnjensen wrote:
... Do you have above ground power in your area? Is it possible you are in an area where a "ground loop" is occurring? How often are the poles grounded? I have seen every pole grounded and some installations where only 1 out of five poles are grounded ... this can result in noise ... indeed, tremendous currents can circulate though the ground ... Regards, JS |
Inline Isolators for RFI reduction ?
On Jan 17, 12:56*am, John Smith wrote:
On 1/16/2011 9:41 PM, bpnjensen wrote: * ... Do you have above ground power in your area? Is it possible you are in an area where a "ground loop" is occurring? How often are the poles grounded? *I have seen every pole grounded and some installations where only 1 out of five poles are grounded ... this can result in noise ... indeed, tremendous currents can circulate though the ground ... Regards, JS That could be a really atrocious scenario, indeed. |
Inline Isolators for RFI reduction ?
On Jan 17, 12:41*am, bpnjensen wrote:
On Jan 16, 8:27*pm, wrote: On Jan 16, 10:13*pm, bpnjensen wrote: On Jan 16, 6:09*pm, John Smith wrote: On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. *That's no joke. *Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here.- Hide quoted text - - Show quoted text - Have you attempted to see if it is coming from the ac 120v outlets? Quite often THAT is one the biggest source of noise . *What receiver(s) /antenna(s) are you using ? Actually, I know that my outlets/switch boxes are sources of buzzing RF *noise. *When *I bring an AM radio, especially one with a tunable loop on it, toward the switches and outlets, the buzzing becomes more audible. *I believe that the house is miswired so that ground and one hot side may be on the same path (this needs to be fixed). I do have an RF-born noise filter that I run the 115 VAC through. *I do not get any serious amount of noise from this source (as far as I can tell) on the radio. *The radio I use primarily is an Icom R75 (also an Allied SX-190 and Realistic DX-160). *Two external antennas - the random wire with 9:1 match, and a DX-Ultra (essentially an all- band dipole, but pretty worthyless on the tropical bands). *The worst noise, by far, is on the lower bands (7 MHz and down). *At 15 MHz and above, the noise is typically minimal and reception is quite good. The tropical bands are a mess, with an S-7/S-9 noise level most of the time. *I can clean up some of it with my MFJ-1026, but not all.- Hide quoted text - - Show quoted text - Have you tried using a 12v battery as a power source ? This may clear things up. |
Inline Isolators for RFI reduction ?
On Jan 16, 9:56*pm, John Smith wrote:
On 1/16/2011 9:41 PM, bpnjensen wrote: * ... Do you have above ground power in your area? Is it possible you are in an area where a "ground loop" is occurring? How often are the poles grounded? *I have seen every pole grounded and some installations where only 1 out of five poles are grounded ... this can result in noise ... indeed, tremendous currents can circulate though the ground ... Regards, JS Good question. I would not be a bit surprised. We have 1950's era aerial power. |
Inline Isolators for RFI reduction ?
On Jan 16, 10:05*pm, wrote:
On Jan 17, 12:41*am, bpnjensen wrote: On Jan 16, 8:27*pm, wrote: On Jan 16, 10:13*pm, bpnjensen wrote: On Jan 16, 6:09*pm, John Smith wrote: On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here.. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. *That's no joke. *Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here.- Hide quoted text - - Show quoted text - Have you attempted to see if it is coming from the ac 120v outlets? Quite often THAT is one the biggest source of noise . *What receiver(s) /antenna(s) are you using ? Actually, I know that my outlets/switch boxes are sources of buzzing RF *noise. *When *I bring an AM radio, especially one with a tunable loop on it, toward the switches and outlets, the buzzing becomes more audible. *I believe that the house is miswired so that ground and one hot side may be on the same path (this needs to be fixed). I do have an RF-born noise filter that I run the 115 VAC through. *I do not get any serious amount of noise from this source (as far as I can tell) on the radio. *The radio I use primarily is an Icom R75 (also an Allied SX-190 and Realistic DX-160). *Two external antennas - the random wire with 9:1 match, and a DX-Ultra (essentially an all- band dipole, but pretty worthyless on the tropical bands). *The worst noise, by far, is on the lower bands (7 MHz and down). *At 15 MHz and above, the noise is typically minimal and reception is quite good. The tropical bands are a mess, with an S-7/S-9 noise level most of the time. *I can clean up some of it with my MFJ-1026, but not all.- Hide quoted text - - Show quoted text - Have you tried using a 12v battery as a power source ? This may clear things up. Not yet, and as RHF also suggested. Maybe worth a try. |
Ensuring You House's Electrical System is Wired Correctly andProperly Grounded
On Jan 16, 9:41*pm, bpnjensen wrote:
On Jan 16, 8:27*pm, wrote: On Jan 16, 10:13*pm, bpnjensen wrote: On Jan 16, 6:09*pm, John Smith wrote: On 1/16/2011 5:07 PM, bpnjensen wrote: ... Short answer - I am getting desperate over the noise level here. Grasping at straws. The fellow I spoke to who makes these things said they are best used as close to the receiver input as possible. You will certainly need to locate the noise source and place the antenna as far away as possible and orientate the antenna so the direction favored by the particular antenna is pointed AWAY form the noise source. * You will probably want to use a 9:1 balun and use coax for the run past any noise source and to provide isolation from noise sources in the home. *A GOOD GROUND on the receiver will serve you well. *If possible, would also be good to ground the coax braid at the antenna, or run a wire down to ground as short as possible ... Regards, JS John, thanks - but my whole neighborhood is a noise source. *That's no joke. *Otherwise, I know all of this already, and have already built it to the best possible configuration, much as you've described here.- Hide quoted text - - Show quoted text - Have you attempted to see if it is coming from the ac 120v outlets? Quite often THAT is one the biggest source of noise . *What receiver(s) /antenna(s) are you using ? - Actually, I know that my outlets/switch boxes are sources of buzzing - RF *noise. *When *I bring an AM radio, especially one with a tunable - loop on it, toward the switches and outlets, the buzzing becomes more - audible. *I believe that the house is miswired so that ground and one - hot side may be on the same path (this needs to be fixed). BpnJ -First- Buy a simple to use AC Outlet/Receptacle Tester http://en.wikipedia.org/wiki/Receptacle_tester for 3-Wire Outlets : Has 3-Lights to Show Proper & Improper Wiring of each and every Outlet that you Test in the House : Do them One-at-aTime & One Room at a Time : One Room per Day by the End of Two Weeks 14-Days you should be Done. * AC Outlet/Receptacle Tester http://www.amazon.com/dp/B002LZTKIA * AC Outlet/Receptacle Tester http://www.tripplite.com/en/products...xtModelID=3941 * AC Outlet/Receptacle Tester http://www.acehardware.com/product/i...ductId=3099774 BpnJ -Second- Next Question : Do You Have 110/120 Volts AC ? * How to Test for AC Outlet Voltage http://www.ehow.com/how_2072916_test-ac-voltage.html * How To Test AC Outlet Voltage http://www.acmehowto.com/howto/homem...letvoltage.php * 120 Volts? Usually but not always... http://www.rocketroberts.com/techart/power.htm -TIP- The Outlet/Receptacle could be Wired Right -but- You could have Bad Wiring to the Outlet and a Voltage Drop down to 85~105 Volts Another way of doing this is with a Power Strip http://en.wikipedia.org/wiki/Power_strip * 6-Outlet Power Strip with 4 Foot Cord http://www.amazon.com/dp/B00006L4F1 Plug two (2) 100 Watt Incandescent Light Bulbs in to it using two (2) of these Plug-In Light Socket Outlet Adapters http://www.amazon.com/dp/B000VL4CFC Now you can Check the Voltage at the Outlet with a 2 Amp Load on it to see if there are any High Resistance Connections causing a Voltage Drop. BpnJ -Third- LAST : Once all this is Tested and Fixed : You only have one thing left : Your Service Entrance Ground. For this Test and Repair you should Call a Licensed Electrician to do the Work. http://www.cdc.gov/nceh/publications...gure_cha11.htm -Safety- If the Electrical Service Entrance Ground is not *R*I*G*H*T* :Then potentially the whole Electrical System of the House is Unsafe. -Conclusion- Once this is all done : You will have the Knowledge and the Confidence in Knowing that your House's Electrical System is Wired Correctly and Properly Grounded. -in-a-word-'safe'-:o)- The First Rule of Shortwave Radio Listeners [SWLs] using Outside SWL Antennas is "SAFETY" [.] hope this helps - iane ~ RHF |
Inline Isolators for RFI reduction ?
On 01/17/2011 05:50 AM, D. Peter Maus wrote:
On 1/16/11 19:14 , bpnjensen wrote: Your wire is likely pulling noise out of your house. If you can't move the wire away from the house, then you do have a bit of a challenge. And isolator will only produce a cleaner path for the radiated noise picked up by your antenna to follow to your receiver. That said, the isolator you're looking at is far more expense than performance for your application. You can do as much with a 9:1 transformer, either prepackaged from Mini-Circuits, or home made by winding around an Amidon toroid worked against an earth ground. Or you could pickup the RF Systems Magnetic Longwire Balun. Also more expense than you need, but it's a good match for what you're trying to achieve, and durable in construction if you're not comfortable growing your own. Anything you want to do, though, will require a good earth ground. Something like the Wellbrook Loop would also be a good choice. Costly, of course. Solid performance, though. And unobtrusive. Or, if you can get away with it, an RF Systems MTA. Now, I have one, and I use it regularly. In a high noise environment, it's very effective. But, man made noise, radiated from the electronics and other appliances in the home...it's not so effective against that. MTA, like the Wellbrook, or the isolation systems you're considering, will be most effective against high levels of atmospheric noise. Less so with man made noise radiated into your antenna space. Have you tried clamp-on ferrite beads on your AC Mains, right at the meter? They have to be the right ferrite mix for low HF and you may need to use more than 1 per leg. That will get all the dimmer buzz and switchmode whistles from the power lines off your home AC. I can vouch for these two papers as being very informative without getting too academic: http://www.audiosystemsgroup.com/RFI-Ham.pdf http://www.audiosystemsgroup.com/SAC0305Ferrites.pdf |
Inline Isolators for RFI reduction ?
On Jan 16, 1:34*pm, RHF wrote:
On Jan 16, 11:24*am, bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? *Such as those sold by Radioworks? Thanks, Bruce Jensen BpnJ : Why are you considering an Inline Isolator ? 1st and "Inline Isolator" requires inserting something 'in-the-line' in the Antenna to Radio Feed-in-Line. 2nd the "Inline Isolator" requires two more Connections {Joints} in the Antenna to Radio Feed-in-Line. *If* Your Antenna to Radio Feed-in-Line is less that 150 Feet : Then most likely you do not need an "Inline Isolator". *If* Your Antenna to Radio Feed-in-Line is on-the-ground or buried-under-the-ground a few inches : Then most likely you do not need an "Inline Isolator". However : If your Antenna to Radio Feed-in-Line is In-the-Air {Overhead} from Tree to House : Then may be you could use and *"Inline Isolator" at the House entry-point with another Grounding Point/Ground Rod. The "Correct Way" to Install a Longwire Antenna and Balun by Wellbrook =http://www.wellbrook.uk.com/longwire.html We have all most likely done it the wrong way more than once . . .http://groups.google.com/group/rec.r...5cc467b35a70d5 *. *. Here is a 1:1 Line Isolator 52 Ohms : Unbalanced Input -to- Unbalanced Output SO239 -to- SO239 for 1.5 to 55 MHz http://www.packetradio.com/catalog/i...ucts _id=2234 |
Inline Isolators for RFI reduction ?
On 01/17/2011 01:15 PM, RHF wrote:
Here is a 1:1 Line Isolator 52 Ohms : Unbalanced Input -to- Unbalanced Output SO239 -to- SO239 for 1.5 to 55 MHz http://www.packetradio.com/catalog/i...ucts _id=2234 . . hmmmmm |
Inline Isolators for RFI reduction ?
I don't think that your RFI issues are going to be solved by isolators. They
will be solved by getting your local power officials to resolve issues with the power lines in your area. bpnjensen wrote: Question to those who may have used one - Do inline isolators work well on RX? Such as those sold by Radioworks? Thanks, Bruce Jensen |
Inline Isolators for RFI reduction ?
On 1/17/2011 1:27 PM, dave wrote:
On 01/17/2011 01:15 PM, RHF wrote: Here is a 1:1 Line Isolator 52 Ohms : Unbalanced Input -to- Unbalanced Output SO239 -to- SO239 for 1.5 to 55 MHz http://www.packetradio.com/catalog/i...ucts _id=2234 . . hmmmmm ROFLOL ... I thought it was bad when I seen those confused by the difference of rf transformers to baluns/unun (TLTs) ... now we have a third term thrown in that must mean "Isolation Transformer." No wonder there is so much confusion out there ... so now we have rf transformers, baluns, ununs, isolation transformers, transmission line transformers and auto-transformers all being covered by the term "line isolator." It is going to fun watching two separate people talking about "line isolators" ... ROFLOL Regards, JS |
Inline Isolators for RFI reduction ?
On 1/17/2011 1:31 PM, dxAce wrote:
I don't think that your RFI issues are going to be solved by isolators. They will be solved by getting your local power officials to resolve issues with the power lines in your area. bpnjensen wrote: I do believe if his antenna is resonate he will increase the signal(s) which are resonate to the background noise ... you post is very deceiving ... Regards, JS |
Inline Isolators for RFI reduction ?
John Smith wrote: On 1/17/2011 1:31 PM, dxAce wrote: I don't think that your RFI issues are going to be solved by isolators. They will be solved by getting your local power officials to resolve issues with the power lines in your area. bpnjensen wrote: I do believe if his antenna is resonate he will increase the signal(s) which are resonate to the background noise ... you post is very deceiving ... k00k |
Inline Isolators for RFI reduction ?
On 1/17/2011 1:36 PM, John Smith wrote:
... ROFLOL ... I thought it was bad when I seen those confused by the difference of rf transformers to baluns/unun (TLTs) ... now we have a third term thrown in that must mean "Isolation Transformer." No wonder there is so much confusion out there ... so now we have rf transformers, baluns, ununs, isolation transformers, transmission line transformers and auto-transformers all being covered by the term "line isolator." It is going to fun watching two separate people talking about "line isolators" ... ROFLOL Regards, JS Oh yeah, and I forgot about "antenna traps", you can toss them in with line isolators also ... Regards, JS |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 1/18/2011 6:56 AM, RHF wrote:
... But it is 'by-design' a "Non-Resonate" Broadband Shortwave Radio Listener's [SWL] Antenna using a Broadbanded* 9:1 Matching Transformer. ~ RHF * Frequency Range : 500kHz to 30 MHz ... I don't know what antenna you are speaking of. But, the original bent of this thread started out with "line isolators", actually traps meant to resonate a single antenna on multiple bands ... usually a dipole, however, can be used on monopoles also ... Regards, JS |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On Jan 18, 9:02*am, John Smith wrote:
On 1/18/2011 6:56 AM, RHF wrote: ... But it is 'by-design' a "Non-Resonate" Broadband Shortwave Radio Listener's [SWL] Antenna using a Broadbanded* *9:1 Matching Transformer. ~ RHF * Frequency Range : 500kHz to 30 MHz ... |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 1/18/2011 11:44 AM, dave wrote:
... No such thing. Those isolators just keep hum away. Hum is not your problem. You are likely hearing triac noise (dimmer buzz, halogen torchieres, waterbed heaters, etc.) over the air. It is coming in or power lines and RF chokes on those lines will stop it at the electrical box. But because you have overhead mains that probably won't help enough. You may be able to reduce it enough to get better results from your phase canceller. I'm peabrainstorming here... What dave was attempting to describe is common mode noise. This is probably at least a portion of your noise, best for you to decide: http://www.w8ji.com/common-mode_noise.htm http://www.dxengineering.com/TechArticles.asp?ID={3F341778-BFE9-4988-AD87-142FD1E04EB2} http://www.yccc.org/Articles/W1HIS/C...S2006Apr06.pdf http://www.hard-core-dx.com/nordicdx...ed/balun3.html The links and scientific/technical papers on Common Mode Noise are simply without end. Feel free to use a search engine and find material which is easy for you to digest ... Regards, JS |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On Jan 18, 10:57*am, John Smith wrote:
On 1/18/2011 10:44 AM, bpnjensen wrote: ... Actually, no, and I am sorry if there was a misunderstanding - I meant an inline (in the coax) RFI reduction system. Baluns/ununs really are NOT an RFI reduction system. *They provide proper impedance matching between antenna and feedline. *Coax, with an rf choke (can be a balun/unun) allows the feedline to run though noisy areas and not pick up the noise there, such as when it enters a house with noise present. Baluns/ununs/rf-transformers, because of the use in gaining a superior match (transfer of signal energy) improves signal to noise ratio, in most instances, and this can appear to be functioning as a "RFI reduction system." Some useful links:http://users.belgacom.net/hamradio/s...alun/balun.htm Regards, JS OK, understood, but I have always thought (based on what I have read) that one of these matching transformers, properly deisgned and grounded, can bleed off some noise to ground. Am I misled? |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On Jan 18, 11:44*am, dave wrote:
On 01/18/2011 10:44 AM, bpnjensen wrote: On Jan 18, 9:02 am, John *wrote: On 1/18/2011 6:56 AM, RHF wrote: ... But it is 'by-design' a "Non-Resonate" Broadband Shortwave Radio Listener's [SWL] Antenna using a Broadbanded* *9:1 Matching Transformer. ~ RHF * Frequency Range : 500kHz to 30 MHz ... I don't know what antenna you are speaking of. *But, the original bent of this thread started out with "line isolators", actually traps meant to resonate a single antenna on multiple bands ... usually a dipole, however, can be used on monopoles also ... Regards, JS Actually, no, and I am sorry if there was a misunderstanding - I meant an inline (in the coax) RFI reduction system. No such thing. Those isolators just keep hum away. Hum is not your problem. You are likely hearing triac noise (dimmer buzz, halogen torchieres, waterbed heaters, etc.) over the air. It is coming in or power lines and RF chokes on those lines will stop it at the electrical box. *But because you have overhead mains that probably won't help enough. You may be able to reduce it enough to get better results from your phase canceller. I'm peabrainstorming here...- Hide quoted text - - Show quoted text - OK, good info. Do you think a magnetic loop could diminish reception of the RFI from the overheads? Like, as Peter M. suggests, a Wellbrook? |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 1/18/11 16:05 , bpnjensen wrote:
On Jan 18, 10:57 am, John wrote: On 1/18/2011 10:44 AM, bpnjensen wrote: ... Actually, no, and I am sorry if there was a misunderstanding - I meant an inline (in the coax) RFI reduction system. Baluns/ununs really are NOT an RFI reduction system. They provide proper impedance matching between antenna and feedline. Coax, with an rf choke (can be a balun/unun) allows the feedline to run though noisy areas and not pick up the noise there, such as when it enters a house with noise present. Baluns/ununs/rf-transformers, because of the use in gaining a superior match (transfer of signal energy) improves signal to noise ratio, in most instances, and this can appear to be functioning as a "RFI reduction system." Some useful links:http://users.belgacom.net/hamradio/s...alun/balun.htm Regards, JS OK, understood, but I have always thought (based on what I have read) that one of these matching transformers, properly deisgned and grounded, can bleed off some noise to ground. Am I misled? Local environmental noise, and static, yes. Man made noise, or noise radiated into the antenna space, not so much, no. A properly designed matching transformer will improve the transfer of antenna output to the receiver. And it will help drain off static buildup on the antenna, and help reduce the noise floor. But, if noise is being radiated into the air, as from powerlines, digital toys, and dimmers and similar sources, and your antenna is picking that up, it will depend on the antenna's ability to discriminate between desired and undesired frequencies whether or not you see a reduction in undesired signals. It sounds as though much of your noise problem is related to your connection to the mains. Mains borne noise is a big problem in radio hobbycraft. Most of the noise in my own area is brought in through the mains. The remainder is radiated from the hundreds of devices throughout the neighborhood. It's possible, though a PITA to do so, to bypass the mains with safety caps between .1 - .01mfd (safety caps are essential, here, for fire prevention) to reduce the irregular impulses on the line. And isolation transformer, balanced to ground will also produce significant results in reducing your noise, but that can be expensive. Your least difficult path may be in isolating your radios from the mains, entirely, and move to battery power. |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 1/18/2011 2:05 PM, bpnjensen wrote:
... OK, understood, but I have always thought (based on what I have read) that one of these matching transformers, properly deisgned and grounded, can bleed off some noise to ground. Am I misled? NO, you are not mislead. They are death on common mode noise. If your problem is common mode noise they work like a miracle ... the signal to noise boost the match ain't bad either ... Regards, JS |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 01/18/2011 02:07 PM, bpnjensen wrote:
On Jan 18, 11:44 am, wrote: On 01/18/2011 10:44 AM, bpnjensen wrote: On Jan 18, 9:02 am, John wrote: On 1/18/2011 6:56 AM, RHF wrote: ... But it is 'by-design' a "Non-Resonate" Broadband Shortwave Radio Listener's [SWL] Antenna using a Broadbanded* 9:1 Matching Transformer. ~ RHF * Frequency Range : 500kHz to 30 MHz ... I don't know what antenna you are speaking of. But, the original bent of this thread started out with "line isolators", actually traps meant to resonate a single antenna on multiple bands ... usually a dipole, however, can be used on monopoles also ... Regards, JS Actually, no, and I am sorry if there was a misunderstanding - I meant an inline (in the coax) RFI reduction system. No such thing. Those isolators just keep hum away. Hum is not your problem. You are likely hearing triac noise (dimmer buzz, halogen torchieres, waterbed heaters, etc.) over the air. It is coming in or power lines and RF chokes on those lines will stop it at the electrical box. But because you have overhead mains that probably won't help enough. You may be able to reduce it enough to get better results from your phase canceller. I'm peabrainstorming here...- Hide quoted text - - Show quoted text - OK, good info. Do you think a magnetic loop could diminish reception of the RFI from the overheads? Like, as Peter M. suggests, a Wellbrook? I have heard amazing things. That model is pricey. You can build an experimental loop for the price of a variable capacitor from MFJ and some scrap coax. |
Five Basic Steps to Better Shortwave Radio Listening [SWL]
On 01/18/2011 02:17 PM, D. Peter Maus wrote:
On 1/18/11 16:05 , bpnjensen wrote: On Jan 18, 10:57 am, John wrote: On 1/18/2011 10:44 AM, bpnjensen wrote: ... Actually, no, and I am sorry if there was a misunderstanding - I meant an inline (in the coax) RFI reduction system. Baluns/ununs really are NOT an RFI reduction system. They provide proper impedance matching between antenna and feedline. Coax, with an rf choke (can be a balun/unun) allows the feedline to run though noisy areas and not pick up the noise there, such as when it enters a house with noise present. Baluns/ununs/rf-transformers, because of the use in gaining a superior match (transfer of signal energy) improves signal to noise ratio, in most instances, and this can appear to be functioning as a "RFI reduction system." Some useful links:http://users.belgacom.net/hamradio/s...alun/balun.htm Regards, JS OK, understood, but I have always thought (based on what I have read) that one of these matching transformers, properly deisgned and grounded, can bleed off some noise to ground. Am I misled? Local environmental noise, and static, yes. Man made noise, or noise radiated into the antenna space, not so much, no. A properly designed matching transformer will improve the transfer of antenna output to the receiver. And it will help drain off static buildup on the antenna, and help reduce the noise floor. But, if noise is being radiated into the air, as from powerlines, digital toys, and dimmers and similar sources, and your antenna is picking that up, it will depend on the antenna's ability to discriminate between desired and undesired frequencies whether or not you see a reduction in undesired signals. It sounds as though much of your noise problem is related to your connection to the mains. Mains borne noise is a big problem in radio hobbycraft. Most of the noise in my own area is brought in through the mains. The remainder is radiated from the hundreds of devices throughout the neighborhood. It's possible, though a PITA to do so, to bypass the mains with safety caps between .1 - .01mfd (safety caps are essential, here, for fire prevention) to reduce the irregular impulses on the line. And isolation transformer, balanced to ground will also produce significant results in reducing your noise, but that can be expensive. Your least difficult path may be in isolating your radios from the mains, entirely, and move to battery power. You need to embrace ferrites. They're like putting a low pass filter is series with your mains. Shunt caps are scary. MOVs, sure. |
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