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The meeting is now over and was a general success. The two talks were unusual but excellent.
The "repair" days on Thursday and Friday did not go as well as one could have hoped.
I worked on the CTC-5 Deluxe which started with a nice blank raster with bad
gray tracking.
Fiddling with the connection to the house RF distribution resulted in a terrible picture.
The fine tuning did not work. This was traced to a bad clutch, which a bit of "working with"
got going "well enough". I set up my own signal setup (Blu-ray player and B-T agile
modulator) which resulted signal which varied with channel. I settled on Ch. 5.
But I forgot the remote so had a limited of patterns (which did include crosshatch.)
(I use patterns of my own divising, .jpegs on a USB stick.) I tweeked the convergence
just a bit. The AGC did not work so I had to use an attenuator. Overnight I visited Walmart
and got a universal remote that allowed access of color patters, clumsily.
The gray tracking was fixed in two minutes into "excellent".
Thursday I attacked color. This set is unique, using R-Y and Q demods. The Q was dead. A lot
of time was spent doing resistance checks using tube extenders, and swapping tubes in the
color section. All the tubes were functioning somewhat but the
resistances were high. I brought in the scope and determined that there was both signal
and 3.58 drive to boith demods and that the matrix at least a bit functional Hours were
lost because I was using the wrong AGC control!
Once I found the right one the AGC started at least a little bit.
The color was all in the R-Y channel --- no Q thus no green or magenta.
Finally I broke down and with several actual "Experts" standing by got out the magic
diddle-stick and tweeked the color demod angle looking at the screen. This resulted in
all colors at least a little. We ran of of time. Picture is horrible but colorful. I
think that at least two full days of alignment is needed after a careful resistance
check and re-resistor session. Probably three days total on the bench.
This set will not get better without a complete total alignment. The B&W bicture is
rather ringy on all channels, especially 3.
It was found that the RF feed was bad ... including some sort of interference.
It was changed to a good one.
Other sets being worked on fared worse. The CT-100 never got color. The Royal Soverign
was never made watchable. There was (as far as I know) nothing wrong
with the Philco Predicta and the repaired feed gave a very nice picture. The two main CBS
color sets were generating their usual gorgeous pictures of Dorothy.
Only one prewar US set was working, a non-RCA TRK-12, giving a mildly dim but OK picture.
One prewar British set was working, a Murphy, but it was misadjusted so badly that only
a "random twister" could have done it. After quite a while trying to figure which knob
did what I got a watchable but dim picture.
Somebody earlier had adjusted the WWII military iconoscope camera and it was producing
a really excellent picture for the low light level it gets. It had a really squared up
raster and a perfectly round test circle.
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