Home |
Search |
Today's Posts |
#1
|
|||
|
|||
Dual connection to same antenna
Telamon wrote:
Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. mike |
#2
|
|||
|
|||
Dual connection to same antenna
In article ubQWj.2239$Yp.2147@edtnps92, m II wrote:
Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. Maybe. At some frequencies it will sum in opposition but not at all frequencies. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. I suggested that you short the outer and inner coax conductor so the wire and coax would function common mode. Essentially the coax would just make the wire part look longer. -- Telamon Ventura, California |
#3
|
|||
|
|||
Dual connection to same antenna
On May 15, 6:19*pm, Telamon
wrote: In article ubQWj.2239$Yp.2147@edtnps92, m II wrote: Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. Maybe. At some frequencies it will sum in opposition but not at all frequencies. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. - I suggested that you short the outer and inner coax conductor - so the wire and coax would function common mode. - - Essentially the coax would just make the wire part look longer. - - -- - Telamon - Ventura, California House -o======------------------------------======x x======-------------------------------======o- Shop -o PL-259 Plug = Coax Cable - Antenna Wire x Shorted End OK that works ~ RHF -but- It brings the 'common-mode' noise from the House to the Shop and the Shop to the House. |
#4
|
|||
|
|||
Dual connection to same antenna
In article
, RHF wrote: On May 15, 6:19*pm, Telamon wrote: In article ubQWj.2239$Yp.2147@edtnps92, m II wrote: Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. Maybe. At some frequencies it will sum in opposition but not at all frequencies. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. - I suggested that you short the outer and inner coax conductor - so the wire and coax would function common mode. - - Essentially the coax would just make the wire part look longer. - House -o======------------------------------======x x======-------------------------------======o- Shop -o PL-259 Plug = Coax Cable - Antenna Wire x Shorted End OK that works ~ RHF -but- It brings the 'common-mode' noise from the House to the Shop and the Shop to the House. . If he is not in his house to make the electrical noise then there should not be a problem right? What do you say to that Mr. Logic Person? -- Telamon Ventura, California |
#5
|
|||
|
|||
Dual connection to same antenna
On May 16, 3:55*pm, Telamon
wrote: In article , *RHF wrote: On May 15, 6:19*pm, Telamon wrote: In article ubQWj.2239$Yp.2147@edtnps92, m II wrote: Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value.. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. Maybe. At some frequencies it will sum in opposition but not at all frequencies. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. - I suggested that you short the outer and inner coax conductor - so the wire and coax would function common mode. - - Essentially the coax would just make the wire part look longer. - House -o======------------------------------======x x======-------------------------------======o- Shop -o PL-259 Plug = Coax Cable - Antenna Wire x Shorted End OK that works ~ RHF -but- It brings the 'common-mode' noise from the House to the Shop and the Shop to the House. *. - If he is not in his house to make the electrical noise - then there should not be a problem right? - - What do you say to that Mr. Logic Person? - - -- - Telamon - Ventura, California Telamon, Houses are filed with . . . 'other' People {Family Members Who each use Electrical Items that Generate RFI and EMF Noise Artifacts PLUS - The ever present Stand-by-Mode and Ready-On / Instant-On Devices that Populate Every Home each with it's own unique Electronic Signature. Telamon - NO LOGIC REQUIRED : It's Just Plain Common Sense. ~ RHF |
#6
|
|||
|
|||
Dual connection to same antenna
On May 16, 5:08*pm, m II wrote:
RHF wrote: It's Just Plain Common Sense. ~ RHF - I DID say that if I'm not in the house, there's no noise. How Do You Prove A Negative ? - Even the computer gets switched right off with a real - switch..not that software only thing at the front of the case. This is very Revealing About You and the Way You 'choose' to Exist in your very 'private' Abode. - The clocks and fridge are the only things running - and produce no noticeable noise. - - mike I Hear Clocks Going Tick-Tock All Through The Night Time is Alive and as . . . Noisy As Hell ! ~ RHF |
#7
|
|||
|
|||
Dual connection to same antenna
RHF wrote:
- I DID say that if I'm not in the house, there's no noise. How Do You Prove A Negative ? By showing that the converse IS true. When I AM in the house, there IS noise. As I shut off the things I use, the noise subsides to nothing. I am assuming there is no electronic anarchy going on after I close the door behind me. - Even the computer gets switched right off with a real - switch..not that software only thing at the front of the case. This is very Revealing About You and the Way You 'choose' to Exist in your very 'private' Abode. So true. The local hermits seek me out for advice. I Hear Clocks Going Tick-Tock All Through The Night Time is Alive and as . . . Noisy As Hell ! ~ RHF I love those old Grandfather clocks. It's really unfortunate about those heavy, sharp edged pendulums. They're just SO easy to swing around during the Festivities..who knew it would cut more than turkey? I'm out now, that's all that counts...that and the restraining order... mike |
#8
|
|||
|
|||
Dual connection to same antenna
On May 16, 7:28*pm, m II wrote:
RHF wrote: - I DID say that if I'm not in the house, there's no noise. How Do You Prove A Negative ? By showing that the converse IS true. When I AM in the house, there IS noise. As I shut off the things I use, the noise subsides to nothing. I am assuming there is no electronic anarchy going on after I close the door behind me. - Even the computer gets switched right off with a real - switch..not that software only thing at the front of the case. This is very Revealing About You and the Way You 'choose' to Exist in your very 'private' Abode. So true. The local hermits seek me out for advice. The Local Hermits and I Commuicate : The Silence Unites Us bringing understanding without words ~ RHF I Hear Clocks Going Tick-Tock All Through The Night Time is Alive and as . . . Noisy As Hell ! ~ RHF I love those old Grandfather clocks. It's really unfortunate about those heavy, sharp edged pendulums. They're just SO easy to swing around during the Festivities..who knew it would cut more than turkey? I'm out now, that's all that counts...that and the restraining order... mike |
#9
|
|||
|
|||
Dual connection to same antenna
In article
, RHF wrote: On May 16, 3:55*pm, Telamon wrote: In article , *RHF wrote: On May 15, 6:19*pm, Telamon wrote: In article ubQWj.2239$Yp.2147@edtnps92, m II wrote: Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. After giving this some thought, I got to wondering... The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. That changed direction will be in opposition to the signal in the main antenna wire. Maybe. At some frequencies it will sum in opposition but not at all frequencies. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. The antenna, apparently, is only as long as the wire portion MINUS the coax length. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. - I suggested that you short the outer and inner coax conductor - so the wire and coax would function common mode. - - Essentially the coax would just make the wire part look longer. - House -o======------------------------------======x x======-------------------------------======o- Shop -o PL-259 Plug = Coax Cable - Antenna Wire x Shorted End OK that works ~ RHF -but- It brings the 'common-mode' noise from the House to the Shop and the Shop to the House. *. - If he is not in his house to make the electrical noise - then there should not be a problem right? - - What do you say to that Mr. Logic Person? - Telamon, Houses are filed with . . . 'other' People {Family Members How do you know he lives with other people? Who each use Electrical Items that Generate RFI and EMF Noise Artifacts If he does live with other people he asks them to keep the noise makers turned off. PLUS - The ever present Stand-by-Mode and Ready-On / Instant-On Devices You turn them off or unplug them. that Populate Every Home each with it's own unique Electronic Signature. Telamon - NO LOGIC REQUIRED : I require logic. It's Just Plain Common Sense. ~ RHF . Your common sense is nonsense. -- Telamon Ventura, California |
#10
|
|||
|
|||
Dual connection to same antenna
m II writes:
Telamon wrote: Instead of just disconnecting the radio and ground you might also want to connect the coax center conductor and shield together at that switch point. The induced voltage in the antenna has an instantaneous vector value. Same on the outer sheathing of the coax. When the signal in the sheath is redirected to the inner conductor, it will, in effect, be changing direction. Have your tried reading "Transmission Line Transformer Book" by Jerry Sevick? I was able to get a copy from a local library using their loan program! They actually found a copy. It is very interesting. I have been wanting to read ``Theory and practical designs for the experimenter'' By Jerry Sevick, W2FMI. 115 pages. It is hard to come by these books. Also the materials listed in the books are not your standard amidon mix#. Getting baluns to work would probably necessitate a nice signal generator, and hopefully spectral analyzer, to say the least. I do have a circuit for measuring forward and reflected radio waves - unfortunately I do not have a shielded enclosure to attach the two metters... It's still laying on some copper clad ... [ ... damn... ] I was going to scan the schematic but the scanner is complaining about windows 7 missing some kind of internet fax twain device. A wireless fax machine. So new and inventive. Anycase; Bill Hickox, K5BDZ ``only an swr meter''. I should take head and advise myself it is probably better to buy a professional SWR meter, but I can't even find a damn aluminium box... Autocenter meters - try dans small parts... That changed direction will be in opposition to the signal in the main antenna wire. reflected swr. I'm thinking that the length of the coax will in effect be subtracted from the antenna length, not added as I had previously thought. watch for standing waves. The antenna, apparently, is only as long as the wire portion MINUS the coax length. velocity factors as well. This is all assuming that the switch is indoors, at the very end of the coax, not where the antenna joins the inner conductor. yeah like finding radio grade coax that hasn't been cut to pieces by comcast yet. mike steve |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Dual Location Connection to Same Antenna Wire - Use Both Ends of theWire | Shortwave | |||
Antenna connection on a Kenwood R-5000? | Shortwave | |||
Chemical to Improve Electrical Connection in Antenna Elements | Antenna | |||
Through the wall antenna connection | Antenna | |||
Antenna Connection on Sat800 | Shortwave |