04-08-14 18:11 Roy Witt wrote to Ed Vance about Resurrected

 RW> {at}MSGID: 
 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.
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