04-08-14 18:11 Roy Witt wrote to Ed Vance about Resurrected   
      
    RW> @MSGID: <53452385.298.amtradio@capcity2.synchro.net>   
    RW> Greetings Ed!   
   Howdy Brer Roy!,   
   -snip-   
    EV> While looking at the two pages for the Worldwide on radiomuseum,   
    EV> I used CTRL and the Scroll Wheel on the mouse to look at the space   
    EV> the twin-lead wire comes from and I would 'THINK' it goes to a 300   
    EV> Ohm Folded Dipole antenna in the space at the bottom of the cabinet.   
      
    RW> No, if you look again, you'll see a red twin lead that is   
    RW> attached to the vertical telescoping antenna, you see that it   
    RW> is plugged into the tuner, on the right of the photo. There is   
    RW> a red antenna that is labeled 'Skyriyder' that has suction cups   
    RW> on it, so it can be mounted to a window and it plugs into the   
    RW> same place as the telescoping antenna, which must be unplugged   
    RW> to use the 'Skyryder' antenna. There is also a hole in the rear   
    RW> cover to run that twin lead inside the radio.   
      
    EV> The other photo shows that wire points towards the speaker, so I   
    EV> figure the wire from the RF section has lost the Folded Dipole that   
    EV> it once had.   
      
    RW> As I explained above, the red twinlead wire and the red   
    RW> 'skyryder' are antenna lead-in and wire wrapped iron core   
    RW> antenna. Rather than run the vertical, I may plug the Skyryder   
    RW> in and mount the antenna horizontally on the window, which   
    RW> faces North-by-East. Maybe there's more out there than it   
    RW> receives on that vertical telescoping antenna. Thanks for the   
    RW> website URL, I can use the info they have there. But, I'm not   
    RW> going to join, since $25 isn't my idea of really needing that   
    RW> info.   
      
   O.K., I sit corrected about that Red Twin-Lead cable.   
      
   I didn't investigate anything else on that web site and didn't know   
   about their request for support was for more than Photos and Schematics   
   of Old Radios.   
      
    EV> A UHF TV Station on Channel 32 came on the air, and I made a Folded   
    EV> Dipole antenna out of some 300 Ohm Twin-Lead such as what is in the   
    EV> back of your Hallicrafter Worldwide RX.   
      
    RW> I've done that before. It works very well. But a log-perodic   
    RW> would work much better for what I want...all UHF channels,   
    RW> 14-69 at 40 miles (in Austin)...   
      
    EV> The Tower was 3 1/2 Miles from our house so I calculated the length   
    EV> of the antenna was 19 Centimeters, so I cut off enough Twin-Lead so I   
    EV> could solder the two leads on each end to each other and cut one wire   
    EV> in the center of the antenna to connected some 300 Ohm wire to it,   
    EV> the other end went to a UHF TV Convertor we got.   
      
    RW> If it was that close, a long wire would have worked just as   
    RW> well. But at least you got some antenna mathematics and   
    RW> building practice. BTW, that should have been 19 inches...I   
    RW> have come up with a formula to make 1/4 wave GPs and   
    RW> multiplying the answer by 4 gives me the a closer length to   
    RW> build a full wavelength dipole; 2808/Freq in MHz = 1/4 wave...I   
    RW> also use 2880 to give a 5% extra length to the GP radials...The   
    RW> antennas I used to build went to the local San Diego HRO store   
    RW> and sold out within a few days.  They always displayed a flat   
    RW> 1.2:1 SWR across the band they were designed for.   
      
   I don't think I even had heard of a Log Periodic Antenna in the early   
   to mid 1960's.   
      
   But a Twin-Lead LPA would be OverKill for 3.5 miles.   
      
   And it would be a bear to make and position by the TV Set.   
      
   Also since it was the 2nd TV Station to be on a UHF Frequency in my   
   area, (the 1st one stopped broadcasting in early 1960), I didn't need   
   a broadband antenna back then, so the antenna worked O.K. for the only   
   one that was in town on UHF back then.   
      
   I can't remember when the Local School System started their TV Station   
   on Channel 15 around here.   
   And it was several years later before another Commercial TV station   
   came on the Air here, and then Everybody had TV Stations on UHF!   
      
   We've only have had two VHF stations, and both of them came on the Air   
   way before any UHF stations did.   
      
   I looked at the book I used back then to calculate the length of   
   Twin-Lead I'd have to cut and one chart says TV Channel 32 back then   
   was 578-584 Mc/s.   
   I looked at another chart in the book to find the wavelength was about   
   52 Centimeters, Half of that is about 26 CM , or about 10.25 Inches.   
      
   Tonight I looked at a ruler and that seems about the length that I   
   recall the antenna being.   
      
   My 19 CM guess earlier was way off the mark, wasn't it? .... ..   
   I do the best I can with what I got, but when I really want to know   
   something I go to the Books I have to get it down to the nitty gritty.   
      
    EV> A neighbor across the street heard about the TV Channel 32 antenna   
    EV> that I made and asked me to make one for them too, I had GOBS of wire   
    EV> so I made one for them.   
      
    RW> Believe it or not, that also works as a CB antenna, which is my   
    RW> very first antenna fabrication. The next one was an all wire   
    RW> ground plane, that was mounted outside my 'radio room' on the   
    RW> second floor of our apartment, c1960?...   
      
   I ran a wire around my radio room up near the ceiling, One Big Loop.   
   I used  it with the DX-40 on 20 Meters.   
   -snip-   
    RW>> That was illegal for a CBer to do, but we did the same thing.   
    RW>> It sure beat looking through a pile of xtals and wasting time   
    RW>> making the change.   
      
    EV> Plus the switch box kept you from opening the case to change a Xtal.   
    EV> -snip-   
      
    RW> Actually, the 11mtr lunch box had a xtal socket on the outside   
    RW> face of the radio, allowing xtal changes on the fly. It was a   
    RW> cumbersome job of keeping track of those umpteen xtals, so we   
    RW> fixed that.   
      
   Oh, O.K., Thanks Roy!   
      
   ... I'm a little tagline. When I grow up I wanna be a novel.   
   --- MultiMail/MS-DOS v0.49   
   --- SBBSecho 2.12-Linux   
    * Origin: telnet & http://cco.ath.cx - Dial-Up: 502-875-8938 (1:2320/105.1)