[GreenKeys] Telephoto machines?

[Sheldon Daitch]

Jack,


never saw any of the machines on wideband circuits, but the wire photo machines used by The Associated Press used essentially conditioned voice grade circuits, as best as I remember.  The portable machines which were compatible with the office machines could use a dial up phone line.


The AP was in the process of transitioning to the newer LaserPhoto machines made by Harris in the late 1970s when I worked at the Raleigh bureau.


We did have one of the old wet paper machines out in the news room area.  It was used to monitor the wirephoto network, and it was made by some company out of Japan.   I have the feeling it was kept running, as the bureau probably had a fair stock of the wet process paper and replacement steel blades on hand and the photo sensitive paper for the LaserPhoto machines was a bit more expensive.


The AP wirephoto standard was an amplitude modulated audio carrier and the level of the audio tone determined the level of black at that moment.  I don't recall if the lower levels were blacker or higher levels were blacker.  In any event, and going from a near 40 year memory, each photo was preceded with a set up tone sequence, which gave a white to black reference, a stair step.  This calibrated the receive machine for the contrast range and eliminated any precise phone line level adjustments for the contrast range.  With that said, if there were any level shifts in the telco carrier equipment during a photo transmission, the contrast range changed in the photo.


The AP and UPI machines were similar but had different standards.  I recall one service trip to the newspaper in Kinston, NC, for their AP wirephoto machine and I really don't remember finding anything major wrong with the machine, but it was still not printing properly.  After listening to the photo barker information, the wirephoto editor's talkup on photos, I realized the voice and locations didn't sound right.  I called AT&T test board and asked if they sending Kinston the correct wirephoto circuit.  Oops.  Patchcord was in the wrong jack.


73


Sheldon


________________________________
From: GreenKeys <greenkeys-bounces at mailman.qth.net> on behalf of Jack <wa2hwj at att.net>
Sent: Sunday, June 28, 2015 12:52 AM
To: greenkeys at mailman.qth.net
Subject: [GreenKeys] Telephoto machines?


Does anyone on the list know what company made the "telephoto"

machines that were used in newspaper offices, etc. When I worked for

Ma Bell I remember working on 50 KB "wideband data" circuits that fed

these things. I recall one was as big as a refrigerator and seemed to take

forever to spit out an 8x10 photo.



The movie people in NY are looking for one or two of these beasts.



Jack K0TTY



NNNN










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