Here is my 2nd RCA CT-100 set! There is a great story behind it!
First, the important RCA numbers on the set:
Cabinet # 861
Chassis # B 8002820
CTR 2 418 L1
C-3207-1 Sub 4
Ok, here we go!
This set was bought in the Los Angeles area on Feb. 17, 1954 by my NOW good friend Frank Grill. Frank worked for KHJ Tv-9 in Hollywood for 50 years! Mostly at the transmitter at the top of Mount Wilson. RCA came to the station and offered CT-100 sets for sale and he bought one. He gave it to his parents. They watched it for a few years, then Frank put it in storage in a shed behind his house. There it sat for over 40 years!
Frank heard I was looking for another set, so he donated it to my collection!
He said it was in perfect working condition when he put it in storage!
You can guess how excited I was, knowing I might have a working set right here in the Los Angeles area!
When I went over to pick up the set, he also gave me a NEW IN THE BOX, 15GP22 CRT!!!!!! "Oh thank you great Television God in the sky!!!!"
The CRT was stored OUTSIDE on his patio for over 40 years, and the box was in sad shape. I was so excited, I packed the stuff in the SUV and raced home!
Time for a few photos!
OK, now for more of the great story on this set!
I really, really, wanted to simply plug it in!!!! I mean "really, really"!!!
After over 37 years in Tv engineering, I knew better! I removed the chassis, checked all the tubes, and found five bad ones! After sitting in a metal building, in the Los Angeles hot sun for over 40 years, I guessed some of the parts "might" have dried out. A quick visual inspection, showed some of the wax covering from most of the chokes had cracked, but the chokes seemed ok. I checked a few of the caps at random with my ESR meter, and they checked good! Oh my,,,,, do I re-form the caps and try to fire it up??? SURE!!!! What have I got to loose now! So I put it all back together, pulled the Ballast resistor.
I received this tech note from Pete Deksnis.
There are issues with cranking the line voltage up slowly with a Variac. According to a RCA publication, when the 6CD6 horz output operates at below 100vac, it tends to draw too much current. It is recommended that the Ballast Resistor be removed from the back of the rectifier cage. This lifts the B+, and the caps can safetly be re-formed. The Balast Resistor is in a can projecting out horizontally from the recitifier cage, in an octal socket. It is attached with one small hex head screw.
Ok, the balast resistor was removed. I attached my trusty AC Cheater cord, plugged it into my Variac, and spent the next few hours cranking up the line voltage 5 volts at a time, every 5 minutes or so. At near 90 volts, all the tubes lit up dim, but steady! I was very scared avout the 15GP21. They are known to leak when old, and if the vacuum was gone, I would see a bright FLASH as the filament burnt out,,,,, I did not!!! YAY!!!! It glowed just like a normal CRT should!!!! At 117vac, I let the set cook for hours. I got just a bit of that dusty smell you get from heated dirt, mouse droppings, and spider webs!
I did clean most of the 40+ years of dirt out before I put the chassis back in!
Well, time to fire it up! I put the Balast Resistor back in, turned the set on, and quickly cranked the voltage on the Variac up to 101 volts. I was shaking in my boots! Waiting for the common sound of exploding caps, I stood there with my trusty fire-putter-outer. No smoke, lots of more musty smell, no audio, no RF, (I did hook up my local cable to the set).
Slowly a RASTER began to appear on the CRT! YES!!!!!!!!!!! It was not centered, and was kinda "green", but that told me the HV was working, and so was the 15GP22!!!! I let it cook for about 15 minutes, then turned avery knob on the set trying to get a real picture on it! No luck,,,,, I did get the RGB gains and blacks to adjust fine. The contrast, focus and convergence also seemed to work, "ok". Not great, just "ok". Hey, not too bad after 40+ years of sitting in a metal shed in the LA sun!
Here is a photo of the first image on the set. Sorry about the poor quality of the photo. I tried to get a photo with the lights off, but the flash kept washing out the image. Just squint your eyes, and you will see a faint rastor on the CRT! This was really great news!
Here is another photo. I enhanced it to show the image better. Sorry about the grain.
Ok, now a few photos of the NIB 15GP22!!!!!
This is what happens when you put a cardboard box outside on the patio for 40+ years!!!! I CRT looks great! No damage that I can see so far,,,,,,
Looking good! I will fire it up some day. Lets hope the seal has not dried out,,,,,,,
Stay tuned! More photos of the restoration coming SOON! Lots of caps to change, now that I can see a raster, but no useable picture,,,,,,,,.
|[Up]||TWO!!! RCA CT-100 1954 Color Tvs! NEW Nov. 9, 2002
|[Mail]||Send EMail to Chuck Pharis Web Page
|[Search]||Search Chuck Pharis Web Page
|[Contents]||Chuck Pharis Web Page Contents
Last modified on Sunday, January 19, 2003