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May 1967 Radio-Electronics
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
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The News Briefs section in
the May 1967 issue of Radio-Electronics magazine carried a few noteworthy
items. The biggest happening in my book is an increasing manufacturing and use of
solid state laser devices (I didn't know they had been around that early). It had
not been very long ago that lasers consisted of rather bulky assemblies with high
voltage power supplies and arrays of mirrors and lenses. The state of the art has
progressed significantly since then to the point that laser diodes cost pennies
apiece and are far higher quality than the one shown here. A public cry about the
cost of television servicing - an average of $8.95 (B&W) or $12.61 (color) -
and the sometimes dubious practices by companies. They didn't know how good they
had it. Read on for more tidbits of the day.
News Briefs:
11/57 |
8/58 |
11/59 |
2/60 |
4/60 |
8/60 |
9/60 |
10/60 |
12/60 |
1/61 |
3/61 |
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7/61 |
8/61 |
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10/61 |
11/61 |
12/61 |
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5/62 |
7/62 |
8/62 |
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10/62 |
11/62 |
3/63 |
4/63 |
6/63 |
8/63 |
9/63 |
11/63 |
2/64 |
3/64 |
7/64 |
8/64 |
12/64 |
8/64 |
9/64 |
1/66 |
3/66 |
8/66 |
9/66 |
1/67 |
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7/67 |
9/67 |
3/68 |
4/68 |
5/68 |
8/68 |
9/68 |
1/69 |
11/69
News Briefs
  Latest on Lasers
How do you take motion pictures of a rocket sled going 4,000 mph? It's simple,
now-you use a laser tracker. Developed by Sylvania for an Air Force testing program,
the laser system is used like radar, bouncing a beam off the moving object. The
return beam generates an error signal which controls the mirror angle (see diagram)
to keep the target "on camera." The sleds, which move at twice the speed of a rifle
bullet, are impossible to photograph manually. Once the laser system is aimed at
the vehicle, however, it tracks with an accuracy of 11;4 feet at 10 miles. Symmetrical
radiation patterns - which make it easier to couple into optical devices - have
been obtained for the first time from a laser. The Bell Telephone Labs development
is a Gallium Arsenide laser using a p+ layer only 2 microns thick, and a stripe
contact on narrow strip of metal, which touches the semiconductor exciting area.
The radiation pattern produced by the device is said to facilitate laser-beam transmission
over long distances. A more consumer-oriented use of lasers is a new system which
is neither television nor movie. General Telephone & Electronics has built an
experimental laser display system which uses photoelectric cells for pickup of a
live scene. This image is transmitted electronically to a light-beam "steering"
device which projects three focused laser beams on a conventional movie screen.
Since each beam is a different primary color - red, green and blue - the combination
on the screen produces full-color images.
Big Brother Listens
The FCC has authorized police agencies to use low-power transmitters on undisclosed
frequencies for surveillance, "stake-outs," and raids.
Because normal police frequencies are known and may be monitored by anyone with
a suitable receiver, the Commission reasoned that police were hindered in their
attempts to capture criminal suspects. For instance, where citizens have been attacked
and robbed in a city park, normal police procedure would be to stake out plain-clothesmen
in the area, equipping them with walkie-talkies. But if they had to use assigned
frequencies, criminals might detect their presence and make the attempt useless.
The FCC rule change (Sec. 89.309) provides for the use of any frequency between
40 and 952 MHz which is available in the Police Radio Service, with a maximum of
2 watts' antenna input power. The Commission also emphasized that the rules " ...
in no sense authorize 'wiretapping' or 'bugging' activities by the police."
TV Service Pricing
In three surveys made last fall, TSA (Television Service Association) of Michigan
determined the average service charges their member shops were using.
Average fee for a home call was $5.92 for b-w and $8.05 for color. For servicing
a set in the customer's home for half an hour, the average charge was $3.03 (b-w)
or $4.56 (color). Thus the total price of a completed service call averaged $8.95
(b-w) or $12.61 (color).
In-shop service bills ran $15.40 (b-w) , $24.78 (color), and $13.51 (portables).
The average hourly shop rate was found to be $8.81 for b-w and $10.08 for color.
As reported in TSA News, the trend in Michigan seems to be toward dividing home-service
fees between the home call itself (time and travel expenses) and work actually performed
at the house (time only).
Some shops also reported making separate charges for pickup and delivery. The
average was around $8.00 for b-w (one man) and $13.00 for color (two men)
Airliner Lands Automatically
The big jet - a Pan American Boeing 727 - left its holding pattern and began
an approach run into New York's Kennedy Airport one night last February. The pilot
manipulated the controls as usual up to the point where he locked the plane's instruments
onto the airfield ILS (instrument landing system). Then he stopped flying the plane,
and a computer aboard the jet brought her smoothly in. It was the first time an
American-built airliner on a regular passenger flight had made a completely automatic
landing.
The automatic landing system promises true all-weather flying in the near future.
Aircraft will be able to land despite weather conditions. "Even though visibility
was not poor," the Pan Am pilot announced to his 98 passengers afterward, "the landing
would have been exactly the same with zero-zero visibility."
The system, developed by Boeing and Sperry-Phoenix, includes an auto-pilot, a
flight-director system, a flare computer, an auto-throttle, and a radio altimeter.
Complete redundancy is used; every unit has its twin to provide backup in case of
equipment failure. Furthermore, the system continuously monitors itself; if not
functioning properly, it won't permit activation. If it fails during operation,
it disconnects itself from the aircraft controls.
Using ALS, the pilot does not relinquish his command, for he can override the
computer at any time.
Pan American has two Boeing 727's equipped for automatic landings, and plans
to outfit more planes soon.
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