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What is the Best Direction to 'Point' a Sloper Antenna for DX ?
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ] & WHY ? Given that it is claimed that in general the Sloper produces it's best reception in the direction of the Bottom-Far-End. Coax Cable to the Feed-Point and Top-End-Feed-Point. Thinking of Rigging a Par Electronics EF-SWL Antenna as a Sloper or buying one of these Pre-Make Slopers. http://www.grove-ent.com/ANT8.html Alpha Delta DX-SWL Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0799.html Eavesdropper Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0013.html i want to know ~ RHF |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 7:11*am, dave wrote:
RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ]& *WHY ? Top-fed slopers in an open space are essentially omnidirectional. *Most of the radiation happens at the feed point. The slantwire and the support structure form a low Q mass that also radiates, equally well in all directions. Dale P. has always recommended using his PAR end-fed as a sloper with the feedpoint near the bottom and thus giving a nice short run to ground. Good omni results and a high radiation angle. I think this would work for me if I did not have such a battery of RFI generators around my home. Bruce |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 10:00*am, bpnjensen wrote:
On Aug 31, 7:11*am, dave wrote: RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ]& *WHY ? Top-fed slopers in an open space are essentially omnidirectional. *Most of the radiation happens at the feed point. The slantwire and the support structure form a low Q mass that also radiates, equally well in all directions. - Dale P. has always recommended using his PAR end-fed as a sloper with - the feedpoint near the bottom and thus giving a nice short run to - ground. *Good omni results and a high radiation angle. *I think this - would work for me if I did not have such a battery of RFI generators - around my home. - - Bruce BpnJ, Now that is very Smart of Dale Par [W4OP] http://www.eham.net/reviews/detail/3707 {Now... Why Didn't I Think of That !?!} Plus -if- you run the Coax Cable directly underneath the Antenna Wire; it would act as a Counterpoise and a more uniform ground field. - simplify - simplify - simplify - Sort of the same approach that Wellbrook in the UK recommends for a Far-End feed-point for a better Inverted "L" Antenna. http://www.wellbrook.uk.com/longwire.html But that would eliminate the Tall rotational Center-Point for directional testing : Which is OK since I am only looking for the best single Direction be it N? E? W? S? I guess that the SWL Sloper Antenna Designs by both Alpha Delta and Eavesdropper were built around using the Side of a House* as the High-Mounting-Point. * Taking what the Customer already has and building on that; to make the installation as simple and easy as possible. {A No Brainer} While most Amateur {Ham} Sloper Antennas generally have a Bottom Feed-Point except for those attached to an existing Tower/Mast. BpnJ - tyvm for the tip ~ RHF |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 7:11*am, dave wrote:
RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. - - Where would you place 'Point' the - - Bottom-Far-End for the best DXing ? - - [ N ? E ? W ? S ? ] & WHY ? - Top-fed slopers in an open space are essentially - omnidirectional. Most of the radiation happens at - the feed point. The slantwire and the support - structure form a low Q mass that also radiates, - equally well in all directions. Dave - Tha is All very True for Transmitting Antennas that are 'Radiating' Power from them; be it 1W, 10W, 100W, 1KW . . . But a Receiving Antenna collecting 'free' Radiated Power from the Either in the order of mW ~ nW : The Direction {lay of the wire}; Ssize {length of the wire}; and Position {angle of the wire} can each and all contribute to the 'general direction' that the Wire will gather 'more' RF Signals from : Given that some RF Signals will be Radiating from a Point-Source and mostly Traveling a specific Path between the originating Point-Source and the specific Location of the Receiving Antenna. in search of the one-best answer . . . ~ RHF [ N ? E ? W ? S ? ] & WHY ? |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 2:45*am, Bob Dobbs wrote:
- - RHF wrote: - - What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. - - Where would you place 'Point' the Bottom-Far-End - - for the best DXing ? [ N ? E ? W ? S ? ] *& WHY ? Given that it is claimed that in general the Sloper produces it's best reception in the direction of the Bottom-Far-End. Coax Cable to the Feed-Point and Top-End-Feed-Point. Thinking of Rigging a Par Electronics EF-SWL Antenna as a Sloper or buying one of these Pre-Make Slopers. http://www.grove-ent.com/ANT8.html Alpha Delta DX-SWL Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0799.html Eavesdropper Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0013.html i want to know ~ RHF . . - If you've got the room to select a direction, why not have a series of stakes at - different points of azimuth and maybe a carabiner fastening setup so the thing - could be quickly changed depending on your preferred direction at the time? - - -- - - Operator Bob - Echo Charlie 42 "OB", Given that I am on the West Coast of the USA Northern California Sierra Foothills. 1 - Receive Trans Pacific Shortwave strongly from New Zealand & Australia & Singapore & China & Japan & Russian Far-East 2 - Receive Shortwave from the East Coast of the USA very good. 3 - Receive Shortwave from South {Latin} America good. 4 - Do NOT receive Shortwave from Europe well. 5 - Do NOT receive Shortwave from Middle-East Region well at all. 6 - Do NOT receive Shortwave from Africa well. 7 - Do NOT receive Shortwave from India etc well. What Diriection would you 'Point' the Bottom-End of a Sloper Antenna for the best DXing from : Europe ? Middle-East ? Africa ? and India ? ? N ? E ? W ? S ? and WHY ? in search of the one-best answer . . . ~ RHF |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 4:01*pm, RHF wrote:
On Aug 31, 7:11*am, dave wrote: RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. - - Where would you place 'Point' the - - Bottom-Far-End for the best DXing ? - - [ N ? E ? W ? S ? ] & *WHY ? - Top-fed slopers in an open space are essentially - omnidirectional. *Most of the radiation happens at - the feed point. The slantwire and the support - structure form a low Q mass that also radiates, - equally well in all directions. -correction- 'Tha' to "That" just for M II :o) - Dave - That is All very True for Transmitting Antennas - that are 'Radiating' Power from them; be it 1W, 10W, - 100W, 1KW . . . But a Receiving Antenna collecting 'free' Radiated Power from the Either in the order of mW ~ nW : The Direction {lay of the wire}; Ssize {length of the wire}; and Position {angle of the wire} can each and all contribute to the 'general direction' that the Wire will gather 'more' RF Signals from : Given that some RF Signals will be Radiating from a Point-Source and mostly Traveling a specific Path between the originating Point-Source and the specific Location of the Receiving Antenna. in search of the one-best answer . . . ~ RHF [ N ? E ? W ? S ? ] & *WHY ? *. *. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 7:18*pm, RHF wrote:
On Aug 31, 2:45*am, Bob Dobbs wrote:- - RHF wrote: - - What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. - - Where would you place 'Point' the Bottom-Far-End - - for the best DXing ? [ N ? E ? W ? S ? ] *& WHY ? Given that it is claimed that in general the Sloper produces it's best reception in the direction of the Bottom-Far-End. Coax Cable to the Feed-Point and Top-End-Feed-Point. Thinking of Rigging a Par Electronics EF-SWL Antenna as a Sloper or buying one of these Pre-Make Slopers. http://www.grove-ent.com/ANT8.html Alpha Delta DX-SWL Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0799.html Eavesdropper Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0013.html i want to know ~ RHF . . - If you've got the room to select a direction, why not have a series of stakes at - different points of azimuth and maybe a carabiner fastening setup so the thing - could be quickly changed depending on your preferred direction at the time? - - -- - - Operator Bob - Echo Charlie 42 "OB", Given that I am on the West Coast of the USA Northern California Sierra Foothills. 1 - Receive Trans Pacific Shortwave strongly from New Zealand & Australia & Singapore & China & Japan & Russian Far-East 2 - Receive Shortwave from the East Coast of the USA very good. 3 - Receive Shortwave from South {Latin} America good. 4 - Do NOT receive Shortwave from Europe well. 5 - Do NOT receive Shortwave from Middle-East Region well at all. 6 - Do NOT receive Shortwave from Africa well. 7 - Do NOT receive Shortwave from India etc well. What Diriection would you 'Point' the Bottom-End of a Sloper Antenna for the best DXing from : Europe ? Middle-East ? Africa ? and India ? ? N ? E ? W ? S ? and WHY ? in search of the one-best answer . . . ~ RHF *. *.- Hide quoted text - - Show quoted text - Though I have not been living on the West coast, nevertheless one cannot expect strong signals from certain areas over there . In dealing with such unstable propagation as we had in the last few years a single antenna may not be sufficient and re-orienting it may not be enough. Over here,in NYC I tried using a commercially made sloper antenna in the early 90's and didn't see it performing substantially better than a simple random length wire. That applies only to my location,that is. . . The best antenna I EVER had was a home-made T2FD. Much quieter,had some gain and it was absolutely omnidirectional as far as I know. It used a 9:1 balun transformer from Palomar (sadly they stopped making it). Reception was outstanding,considering the RFI and other man-made noise omnipresent over here. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 10:37*pm, wrote:
On Aug 31, 7:18*pm, RHF wrote: On Aug 31, 2:45*am, Bob Dobbs wrote:- - RHF wrote: - - What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. - - Where would you place 'Point' the Bottom-Far-End - - for the best DXing ? [ N ? E ? W ? S ? ] *& WHY ? Given that it is claimed that in general the Sloper produces it's best reception in the direction of the Bottom-Far-End. Coax Cable to the Feed-Point and Top-End-Feed-Point. Thinking of Rigging a Par Electronics EF-SWL Antenna as a Sloper or buying one of these Pre-Make Slopers. http://www.grove-ent.com/ANT8.html Alpha Delta DX-SWL Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0799.html Eavesdropper Sloper Antenna http://www.universal-radio.com/catalog/sw_ant/0013.html i want to know ~ RHF . . - If you've got the room to select a direction, why not have a series of stakes at - different points of azimuth and maybe a carabiner fastening setup so the thing - could be quickly changed depending on your preferred direction at the time? - - -- - - Operator Bob - Echo Charlie 42 "OB", Given that I am on the West Coast of the USA Northern California Sierra Foothills. 1 - Receive Trans Pacific Shortwave strongly from New Zealand & Australia & Singapore & China & Japan & Russian Far-East 2 - Receive Shortwave from the East Coast of the USA very good. 3 - Receive Shortwave from South {Latin} America good. 4 - Do NOT receive Shortwave from Europe well. 5 - Do NOT receive Shortwave from Middle-East Region well at all. 6 - Do NOT receive Shortwave from Africa well. 7 - Do NOT receive Shortwave from India etc well. What Diriection would you 'Point' the Bottom-End of a Sloper Antenna for the best DXing from : Europe ? Middle-East ? Africa ? and India ? ? N ? E ? W ? S ? and WHY ? in search of the one-best answer . . . ~ RHF *. *.- Hide quoted text - - Show quoted text - - Though I have not been living on the West coast, - nevertheless one cannot expect strong signals - from certain areas over there . In dealing with - such unstable propagation as we had in the last - few years a single antenna may not be sufficient - and re-orienting it may not be enough. - Over here,in NYC I tried using a commercially made - sloper antenna in the early 90's and didn't see it - performing substantially better than a simple - random length wire. That applies only to my - location,that is. . . - The best antenna I EVER had was a home-made - T2FD. *Much quieter,had some gain and it was - absolutely omnidirectional as far as I know. T2FD : Terminated Tilted Folded Dipole Shortwave Antenna http://www.johncon.com/john/T2fd/ - It used a 9:1 balun transformer from Palomar - (sadly they stopped making it). -fyi- The Palomar Engineers "MLB-1" Magnetic Longwire Balun for Shortwave {Radio} Listening Antennas is still being made. ~$50US http://www.palomar-engineers.com/MLB-1/mlb-1.html -*Reception was outstanding,considering the RFI - and other man-made noise omnipresent over here. Several years ago I bought a used Wellbrook [UK] Universal Magnetic Balun UMB T2FD and never http://www.wellbrook.uk.com/UMBT2FD.html got around to using it. IIRC it is somewhere down in sub-basement # 3 -but- like I bought it and stuck it on a shelf and don't think that I have seen it in years. Heck I have not been down to check out sub-basement # 3 in years . . . hope that the sump pumps are still working . . . got to add that to my To-Do List on the next trip to Alameda, CA. I already have two SWL Antennas up here in Twain Harte, CA -but- neither seems bring in Europe; the Middle-East; Africa and India. |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
RHF wrote:
On Aug 31, 10:00 am, wrote: On Aug 31, 7:11 am, wrote: RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ]& WHY ? Top-fed slopers in an open space are essentially omnidirectional. Most of the radiation happens at the feed point. The slantwire and the support structure form a low Q mass that also radiates, equally well in all directions. - Dale P. has always recommended using his PAR end-fed as a sloper with - the feedpoint near the bottom and thus giving a nice short run to - ground. Good omni results and a high radiation angle. I think this - would work for me if I did not have such a battery of RFI generators - around my home. - - Bruce BpnJ, Now that is very Smart of Dale Par [W4OP] http://www.eham.net/reviews/detail/3707 {Now... Why Didn't I Think of That !?!} Plus -if- you run the Coax Cable directly underneath the Antenna Wire; it would act as a Counterpoise and a more uniform ground field. - simplify - simplify - simplify - Sort of the same approach that Wellbrook in the UK recommends for a Far-End feed-point for a better Inverted "L" Antenna. http://www.wellbrook.uk.com/longwire.html But that would eliminate the Tall rotational Center-Point for directional testing : Which is OK since I am only looking for the best single Direction be it N? E? W? S? I guess that the SWL Sloper Antenna Designs by both Alpha Delta and Eavesdropper were built around using the Side of a House* as the High-Mounting-Point. * Taking what the Customer already has and building on that; to make the installation as simple and easy as possible. {A No Brainer} While most Amateur {Ham} Sloper Antennas generally have a Bottom Feed-Point except for those attached to an existing Tower/Mast. BpnJ - tyvm for the tip ~ RHF . . I have an Alpha Delta DX-B half sloper. It feeds at the top. That's why it works so good. The current max is 40 feet in the air. |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
RHF wrote:
Dave - Tha is All very True for Transmitting Antennas that are 'Radiating' Power from them; be it 1W, 10W, 100W, 1KW . . . Reciprocity says that the same rules apply to receiving. Here's the listen only version of the Alpha Delta. It is top fed for best performance as well. http://www.alphadeltacom.com/dxswlii.htm |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
RHF wrote:
What Diriection would you 'Point' the Bottom-End of a Sloper Antenna for the best DXing from : Europe ? Middle-East ? Africa ? and India ? ? N ? E ? W ? S ? and WHY ? in search of the one-best answer . . . ~ RHF . . Have you generated a Great Circle map centered on your location? That would be step one. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 1, 3:49*pm, dave wrote:
bpnjensen wrote: On Sep 1, 3:44 am, *wrote: I already have two SWL Antennas up here in Twain Harte, CA -but- neither seems bring in Europe; the Middle-East; Africa and India. That's why they call it DX, I guess! *Our California location simply is not at anybody's target area, and only occasionally off the backside of the beam. *If we were in someone's sights, or if we had that extra bit of ocean between us and them, we'd probably hear them better. Also, most of the European stations either totally ignore NA or else use relays to get their point across, resulting in service only from other locations. *The ones that still use their native soils for transmitting to us - Czechia, Romania, Albania - all manage fairly well some of the time. India is especially absent from California airwaves. *Don't know why, exactly. Bruce Jensen Antipodal? Maybe - but I get other such stations fairly regularly - RN/VOA Madagascar, BBC Seychelles, Sri Lanka...? |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 1, 3:49*pm, dave wrote:
bpnjensen wrote: On Sep 1, 5:43 am, *wrote: RHF wrote: On Aug 31, 10:00 am, * *wrote: On Aug 31, 7:11 am, * *wrote: RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ]& * * *WHY ? Top-fed slopers in an open space are essentially omnidirectional. *Most of the radiation happens at the feed point. The slantwire and the support structure form a low Q mass that also radiates, equally well in all directions. - Dale P. has always recommended using his PAR end-fed as a sloper with - the feedpoint near the bottom and thus giving a nice short run to - ground. *Good omni results and a high radiation angle. *I think this - would work for me if I did not have such a battery of RFI generators - around my home. - - Bruce BpnJ, Now that is very Smart of Dale Par [W4OP] http://www.eham.net/reviews/detail/3707 {Now... Why Didn't I Think of That !?!} Plus -if- you run the Coax Cable directly underneath the Antenna Wire; it would act as a Counterpoise and a more uniform ground field. - simplify - simplify - simplify - Sort of the same approach that Wellbrook in the UK recommends for a Far-End feed-point for a better Inverted "L" Antenna. http://www.wellbrook.uk.com/longwire.html But that would eliminate the Tall rotational Center-Point for directional testing : Which is OK since I am only looking for the best single Direction be it N? E? W? S? I guess that the SWL Sloper Antenna Designs by both Alpha Delta and Eavesdropper were built around using the Side of a House* as the High-Mounting-Point. * Taking what the Customer already has and building on that; to make the installation as simple and easy as possible. {A No Brainer} While most Amateur {Ham} Sloper Antennas generally have a Bottom Feed-Point except for those attached to an existing Tower/Mast. BpnJ - tyvm for the tip ~ RHF * *. * *. I have an Alpha Delta DX-B half sloper. It feeds at the top. *That's why it works so good. The current max is 40 feet in the air.- Hide quoted text - - Show quoted text - How do you suspend the top? 50' telescoping mast and lots of Dacron I like it! :-) |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Aug 31, 7:11*am, dave wrote:
RHF wrote: What is the Best Direction to 'Point' a Sloper Antenna for DX ? Given an area where you could locate a Sloper Antenna with a Tall Mounting Pole "Top-End-Feed-Point' and the ability to move the Bottom-Far-End around the full circle of 360 Degrees. Where would you place 'Point' the Bottom-Far-End for the best DXing ? [ N ? E ? W ? S ? ]& *WHY ? - Top-fed slopers in an open space are essentially - omnidirectional. OK but most are 'in' close-in space with all sorts of things around them. -*Most of the radiation happens at the feed point. Yes there is more power radiating around the feed-point. -but- I a talking about a SWL Receiving Antenna. - The slantwire and the support structure form a - low Q mass that also radiates, equally well in - all directions. Not 'If' the Support Structure is a Grounded Metal Tower/Mast. Many of the Commercial Slopers use an attached Counterpoise Insulated Wire to hang-down to the ground along the Side of a Building to act as the Grounded Tower/Mast {Reflector} to give the Sloper some directivity and to better 'Match' the Antenna to the Feed-in-Line. http://www.universal-radio.com/catalog/sw_ant/0013.jpg http://www.alphadeltacom.com/images/dxswl.gif http://t2k.wdfiles.com/local--files/...sloper-002.jpg "A Sloper which is at an angle they will be more directional the direction that they are sloped." http://www.angelfire.com/mb/amandx/dipole.html Full 1/2 Wave Sloper Antenna : The radiation pattern will be almost omnidirectional ... with a slight advantage toward the "sloping" direction. http://www.hamradiosecrets.com/ham-r...f-antenna.html Half 1/4 Wave Sloper Antenna : Omni-Directional pattern, but with some "warping" in the direction of the wire slope. http://mysite.ncnetwork.net/resvzazs/80endfed.htm 1/4 Wave Sloper : It does appear to offer gain in the direction of the sloping element. http://home.centurytel.net/WD0M/antennas1.html Some of this may be the fact that these Slopers are Mounted to Metal Towers/Masts and the Grounded Tower/Mast may be acting like a back Reflector and causing some of the Radiated Directivity from the Tower to the Sloping Wire and out away from them. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
"Just Plain Burr" wrote in message
... Lighting did get me from my Wi-Fi. It jumped around on my desk so fast and was over before I could move. All radios were OK. Lightening not lighting I presume. From your Wi-Fi? In what sense from your Wi-Fi? -- Brian Gregory. (In the UK) To email me remove the letter vee. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
wrote in message
... Palomar's currently sold 9:1 transformer is good only for a longwire, but not for T2FD. How can that be? -- Brian Gregory. (In the UK) To email me remove the letter vee. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 2, 5:21*pm, "Brian Gregory [UK]" wrote:
wrote in message ... Palomar's currently sold 9:1 transformer is good only for a longwire, but not for T2FD. How can that be? -- Brian Gregory. (In the UK) To email me remove the letter vee. Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 2, 10:41*pm, wrote:
On Sep 2, 5:21*pm, "Brian Gregory [UK]" wrote: wrote in message .... - - - Palomar's currently sold 9:1 transformer - - - is good only for a longwire, but not for T2FD. - - How can that be? -- Brian Gregory. (In the UK) To email me remove the letter vee. - *Because the presently made MLB-1 by Palomar Engineersis a UNUN for a - longwire. The older transformer which I used (may have the original - instruction paper somewhere) was a true BALUN. To build a T2FD we must - use a balun, since it is a broadband dipole. Buy the PAR Balun which has a Floating Ground Termainal which makes it an BAL-UN or you can connect the Floating Ground to the Coax Ground and have a UN-UN. http://www.monitoringtimes.com/html/...-SWL%20Antenna Opps to Buy the PAR Balun you have to buy the PAR EF-SWL Antenna which includes the http://www.grove-ent.com/ANT8.html http://www.parelectronics.com/pdf/EF-SWL.pdf http://www.universal-radio.com/catalog/sw_ant/2205.html Balun and 45 Feet of HQ* Antenna Wire. "Flex Weave" covered by a protective black polyethylene jacket. * 45 Feet of AWG #14 Black Polyethylene Coated "Flex-Weave" Antenna Wire which is made up of 168 Strands of #36 Gauge Woven Copper Wires. {This is Great Stuff} http://www.radiobanter.com/showthread.php?t=124225 Yes with the PAR EF SWL Antenna you can Rig-It Your Way ! - iane ~ RHF |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
wrote in message
... Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. A long wire balun should not assume you want a common ground connection on the input and output. But I've look at the picture and description of the MLB-1 on the web and I agree it's far from clear what connections are provided. However if I bought it and found it did have the grounds joined I'd return it as unacceptable because when using a long wire you want to use a separate good quality earth which is not joined to your receiver's earth which may have RF noise on it. -- Brian Gregory. (In the UK) To email me remove the letter vee. |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
Brian Gregory [UK] wrote:
wrote in message ... Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. A long wire balun should not assume you want a common ground connection on the input and output. But I've look at the picture and description of the MLB-1 on the web and I agree it's far from clear what connections are provided. However if I bought it and found it did have the grounds joined I'd return it as unacceptable because when using a long wire you want to use a separate good quality earth which is not joined to your receiver's earth which may have RF noise on it. I disagree. Use on an UnUn (autotransformer) puts all points of the system at ground, provided you ground per electrical code. "Noise" from the radio chassis (?) flows to ground through the IEC cable. Static charges from the antenna system flow to ground at the transmission line point of entry. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 3, 10:49*am, dave wrote:
RHF wrote: On Sep 2, 10:41 pm, wrote: On Sep 2, 5:21 pm, "Brian Gregory *wrote: *wrote in message .... - - - Palomar's currently sold 9:1 transformer - - - is good only for a longwire, but not for T2FD. - - How can that be? Your Way ! - iane ~ RHF * . You can use 450 Ohm ladder line to feed your T2FD Very true,but the interference won't allow appropriate low-noise reception at my location. I have to use coax. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 3, 11:03*am, "Brian Gregory [UK]" wrote:
wrote in message ... Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. A long wire balun should not assume you want a common ground connection on the input and output. But I've look at the picture and description of the MLB-1 on the web and I agree it's far from clear what connections are provided. However if I bought it and found it did have the grounds joined I'd return it as unacceptable because when using a long wire you want to use a separate good quality earth which is not joined to your receiver's earth which may have RF noise on it. -- Brian Gregory. (In the UK) To email me remove the letter vee. MLB-1 from Palomar is probably (I would rate that at 99%) their answer to the MLB from RF Systems in the Netherlands. I still have the latter and it has only one connection for the antenna on the top. P.S. Just checked back Palomar's website and a true 9:1 balun kit is still available,but it is made for transmitting up to 250W,not for SWL and does not have any enclosure box. And it is certainly much bigger and heavier than the old one I originally used for T2FD. |
What is the Best Direction to 'Point' a Sloper Antenna for DX ?
On Sep 3, 9:15*pm, dave wrote:
Brian Gregory [UK] wrote: *wrote in message ... Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. A long wire balun should not assume you want a common ground connection on the input and output. But I've look at the picture and description of the MLB-1 on the web and I agree it's far from clear what connections are provided. However if I bought it and found it did have the grounds joined I'd return it as unacceptable because when using a long wire you want to use a separate good quality earth which is not joined to your receiver's earth which may have RF noise on it. I disagree. Use on an UnUn (autotransformer) puts all points of the system at ground, provided you ground per electrical code. *"Noise" from the radio chassis (?) flows to ground through the IEC cable. Static charges from the antenna system flow to ground at the transmission line point of entry.- Hide quoted text - - Show quoted text - My own cell-phone generates more noise than some of the cold war era jammers,sometimes! That is another reason for using coax. And grounding may bring more problems,sometimes it is better not to ground. Static usually is not a major issue over here at my lattitude (40* N). |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
On 9/3/2010 10:01 PM, dave wrote:
... Common mode rejection of noise happens in a truly balanced configuration. That is the worst suggestive BS I have ever seen, no antenna knows the difference between "RF noise" and a desirable RF signal ... Regards, JS |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
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What is the Best Direction to 'Point' a Sloper Antenna for DX ?
"dave" wrote in message
. .. Brian Gregory [UK] wrote: wrote in message ... Because the presently made MLB-1 by Palomar Engineersis a UNUN for a longwire. The older transformer which I used (may have the original instruction paper somewhere) was a true BALUN. To build a T2FD we must use a balun, since it is a broadband dipole. A long wire balun should not assume you want a common ground connection on the input and output. But I've look at the picture and description of the MLB-1 on the web and I agree it's far from clear what connections are provided. However if I bought it and found it did have the grounds joined I'd return it as unacceptable because when using a long wire you want to use a separate good quality earth which is not joined to your receiver's earth which may have RF noise on it. I disagree. Use on an UnUn (autotransformer) puts all points of the system at ground, provided you ground per electrical code. "Noise" from the radio chassis (?) flows to ground through the IEC cable. Static charges from the antenna system flow to ground at the transmission line point of entry. All I ccan suggest is that you try it. If I comapre reception on the lower bands between using my own earth made from a copper pipe hammered into the ground somewhat away from the house to that using the mains earth I find there is way more noise using the mains earth and using both earths is almost as bad. -- Brian Gregory. (In the UK) To email me remove the letter vee. |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
John Smith wrote:
On 9/3/2010 10:01 PM, dave wrote: ... Common mode rejection of noise happens in a truly balanced configuration. That is the worst suggestive BS I have ever seen, no antenna knows the difference between "RF noise" and a desirable RF signal ... Regards, JS I think what Dave was saying is that open wire feeders will not pick up noise (or signals, for that matter) if they are truly balanced, because of common mode rejection. Which is true. With all good wishes, Kevin, WB4AIO. -- http://kevinalfredstrom.com/ |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
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Balanced Lines Antenna for DX ?
John Smith wrote:
On 9/3/2010 10:01 PM, dave wrote: ... Common mode rejection of noise happens in a truly balanced configuration. That is the worst suggestive BS I have ever seen, no antenna knows the difference between "RF noise" and a desirable RF signal ... Regards, JS The noise is in-phase and cancels when the transmission line is terminated in a "differential" input. The desired signal is + on one leg and - on the other. The desired signal remains after differential summation. John, lo: http://en.wikipedia.org/wiki/Balanced Any external signal sources tend to induce only a common mode signal on the line and the balanced impedances to ground minimizes differential pickup due to stray electric fields. The conductors are sometimes twisted together to ensure that each conductor is equally exposed to any external magnetic fields that could induce unwanted noise. Some balanced lines also have electromagnetic shielding to reduce the amount of noise introduced. A balanced line allows a differential receiver to reduce the noise on a connection by rejecting common-mode interference. The lines have the same impedance to ground, so the interfering fields or currents induce the same voltage in both wires. Since the receiver responds only to the difference between the wires, it is not influenced by the induced noise voltage. If twisted pair becomes unbalanced, for example due to insulation failure, noise will be induced. Examples of twisted pairs include Cat-3 Ethernet cables or telephone wires. Compared to unbalanced circuits, balanced lines reduce the amount of noise per distance, allowing a longer cable run to be practical. This is because electromagnetic interference will affect both signals the same way. Similarities between the two signals are automatically removed at the end of the transmission path when one signal is subtracted from the other. [edit] |
What is the Best Direction to 'Point' a Sloper Antenna for DX?
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What is the Best Direction to 'Point' a Sloper Antenna for DX ?
"dave" wrote in message
. .. wrote: - Show quoted text - My own cell-phone generates more noise than some of the cold war era jammers,sometimes! That is another reason for using coax. And grounding may bring more problems,sometimes it is better not to ground. Static usually is not a major issue over here at my lattitude (40* N). GMS phones seem to get into everything. I'd look for an audio path, not via HF radio circuitry. Snow blowing across a wire antenna generates static electricity. Grounding the transmission line where it enters a structure is consistent with good operating practice. My radio floats on a 13 VDC switch mode power supply. The only ground is the coaxial cable from the feedthru. Have you tried using batteries, or even a linear power supply. You may be amazed how much noise on the lower bands just vanishes when you do. -- Brian Gregory. (In the UK) To email me remove the letter vee. |
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