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Walter Maxwell · August 2nd 06, 11:29 PM posted to rec.radio.amateur.antenna

On Wed, 02 Aug 2006 15:54:26 GMT, (Rick) wrote:

On Wed, 02 Aug 2006 11:18:07 -0400, Walter Maxwell
wrote:

During the period between 1958-59 I designed the entire antenna system and
matching harness for the World's first weather satellite, TIROS 1, which was
launched April 1, 1960.

Walt,
Could you please tell me a little more about that satellite? Reason I
ask is there is a place I am sure you can enlighten us on, called Camp
Evans.
I know there is still a big dish antenna there, although the wooden
structure surrounding it is failing. Supposedly it was used for
communicating with Tiros. Is that right?

A NJ radio club had a hamfest there in April, and I was able to walk
under the antenna and they have some displays there. Supposedly Camp
Evans was also the place where the first signals were bounced off the
moon, somewhere around 1946.
Camp Evans looks like at least parts of it are being renovated.
Brookdale Comm. College has some classrooms there, very modern.
Oh yes, and on the road leading to Camp Evans (Marconi Road !!) there
is a display of the top portion of one of Marconi's towers, and a
plaque noting that there were many such towers in the area in the
early 1900s.
Quite a bit of radio history, in these parts of New Jersey, and I am
glad to know one of the pioneers frequents this newsgroup.
Not far away, in Holmdel, is where AT&T communicated with Telstar, I
believe, about the same time period. The Holmdel facility, home to
6000 Bell Labs employees as recently as1999 has been sold and is going
to be demolished.

Rick K2XT

Hi Rick,

Thanks for the response to my post.

The first eight versions of TIROS were shaped as a short 18-sided cylinder about
30 inches in diameter and about two feet tall. It contained a 1/2 inch vidicon
video camera and an infra red (IR) sensor. Direct viewing of both the camera and
IR sensor was attained whenever the spacecraft was within sighting distance of
the three ground stations, one at Ft. Monmouth, NJ, one at our RCA Space Center
at Hightstown, NJ, (where we built the spacecraft) which I operated, and one in
Australia.

There were also two tape recorders that recorded the video and IR when over
other places on Earth out of range of the ground stations, for playback when in
range.

The video and IR transmitters each delivered 5 watts, the video on 235 MHz and
the IR on 237.8 MHz. There were two beacon and telemetry transmitters, one on
108 MHz and the other on 108.03 MHz, each delivering 30 milliwatts. Beginning
with TIROS 3 and on through 8, the beacon-telemetry transmitter frequencies were
changed to 136.0 and 136.5 MHz, leaving the 108 MHz frequencies free for
aircraft communications.

The monopole antennas were sleeve type. A half-inch sleeve 1/4 wl long at 236
MHz radiated the video and IR signals, and a rod extension, along with the
sleeve, radiated the 108 MHz signals. The internal portion of the sleeve formed
a quarter-wave shorted transmission line that decoupled the rod extension at the
235 and 237.8 MHz frequencies, as part of the frequency-separation circuitry
that allowed the antenna to operate on the two frequency bands separated by
approximately an octave.

I have a number of pictures of the spacecraft in various views in JPG format
that I'll send to you as soon as I can get them together.

Now concering Camp Evans, I'm not sure that that was the location of the TIROS
dish, which was 28 feet in diameter. All I can recall after all these years is
that the dish was at Ft. Monmouth, the location of USASRDL, the Signal Corps
Development Laboratory. Camp Evans might have been on the Ft. Monmouth Army
Base, but I just can't remember.

I knew several of the engineering guys at Bell Labs Holmdel, but all I knew
there have passed on.

Hope this helps,

Walt, W2DU