The CTC-5 Made it to Germany already!

[roundscreen]

Eckhard. I have some 6Cg7 readings withAC@110. B+292v{filters check ok} horz current 205-206 ma. horz drive -28 {changed some caps}.
pin 2. - 18v
pin 3. I get .140 dc and 20v when I switch the meter to ac {may be my meter is loading it down}
pin 6. 200v { meter loads this line down too and horz lock goes out}
pin 7. -65v
The picture dosen't look that great but you can see the bars look almost the same width. The sides of the screen are in a little with the width set to the middle. When I turn the width to high the bars look normal with an increase of 1ma on the horz current This set has a 21fjp22 in it. When my buddie had it The crt blew out when the flyback started to cook. Took out the 6bk4 and other parts too. I used this cabinet as a jig to repair my other chassis. Did not want to work around the 21axp crts.{Accident prone}. Question. Have you done any adjustments to the horz lin coil? You may want to try and put your finger on the horz lin coil to see if it gets warm or hot run the set for 15min then check it. You can take the screen off the bottom of the set and be able to put your finger on it. Also if you adjust the horz drive up. Do you get a fold over on the right side of the screen?
ED

[roundscreen]

Here is a picture of the chassis#

[yagosaga]

Thank you for all that informations. Last night I soldered new resistors on the horizontal oscillator unit. When brought the set in operating mode again I read that horizontal output current increased up to 450ma.and I switched off the set at once. At the grid of the 6CB5 I found appr. +300v. !!! When I evaluated the unit I found a (small, just invisible soldered) short between c603 and R165 (on the printed circuit). Shame about me! Full B+ at grid of 6CB5. I tested 6CB5: short between screen and grid. After repairing +5v remained at the grid of the 6CB5. Next I will remove the chassis and will operate it outside the set, only for repairing and servicing the horizontal oscillator which is not working. Hope that nothing important more is defect - never touch a running system... hahaha.

[yagosaga]

Hi folks! The ctc-5 is working again!
Beside the defect 6cb5, which I have replaced with the old 6cg5, I found a defect at the sine coil. Because of the extreme positive voltage at grid of the 6cb5 this voltage is linked to the grid of the 6cg7 too (via R165). The high current of the 6cg7 had burned out the sine coil. I found an interuption at one feet of the coil which could be soldered carefully.
For testing the chassis without crt and horizontal output unit I inserted a 4K 50watts resistor between chassis ground and +385v and used the 105v ac source to get clear +385v.
Without 385v d.v. at the horizontal output unit, I have now the correct -89v at grid of 6cg7 and -39v at grid of 6cb5 !!
Then I inserted the chassis into the set, testmeter at horizontal output current and grid of 6cb5, high voltage probe. The results: horizontal output current is 208ma, picture has full horizontal width, even in the smallest switch position.
The next readings: -37.8v at the grid of 6cb5 !! 19.25kv with the hv probe.
Some remarks: R608 has 103K. Plate voltage on pin 1 of the 6cg7 is 293v.
While renewing the resistors I found that R603 has 90K, should be 150K I have soldered a 150K resistor instead of 90K!
The other resistors had no out-of-tolerance values but some of them were crumbly, they broke while removing.
In the next days I will watch the set and its flyback how warm or hot it will be after 15, 30, 45 and 60 minutes.
Thank you for all your support and patience with me.

[roundscreen]

Mistakes, don't ya hate that. 450 ma now thats some horz drive. When I solder boards I take a small screwdriver and scrape the board around the traces and connections I worked on. Since i am a walking mistake I double check all the work I do.
and find them way to many times. When things go bad, Some times it is best to take a break from it.

[roundscreen]

So glad to hear you fixed your set. Now you can enjoy watching it. Have fun.
ED

[Bill R]

Sounds like you have it. Nice work.

[yagosaga]

Originally Posted by Steve K

Here is the horizontal section of the CTC-7. I also have the schematic for the 9. Is this the only part you wanted to see or would you like the entire schematics?

Steve, please send me the schematics for the ctc-7 and for the ctc-9 if you have them in a digitized form.

Originally Posted by roundscreen

Mistakes, don't ya hate that. 450 ma now thats some horz drive. When I solder boards I take a small screwdriver and scrape the board around the traces and connections I worked on. Since i am a walking mistake I double check all the work I do.

Usually I take a small screwdriver too and scrape the board around the traces and connections I work on. But the boards of this vintage set are very old and I thought that I would damage it by doing this. Therefore I didn't do it this time. You know the results. )-:
But I'm very happy that nothing more was destroyed and hope so. This I thank you, because I had always running the meters and I see on them that something unexpected happened very fast. If I hadn't run the meters I probably had first noticed the defect when smoke and fire came out of the chassis.

Originally Posted by Bill R

Sounds like you have it. Nice work.

Yes, it seems so. I noticed that the control range of the horizontal frequency has become smaller. When I turn the core of the horizontal hold, the brightness is getting darker or brighter, I can see that this has an effect on the horizontal output drive. In the momemt I can only display a tv program with CCIR / Gerber format, i.e. 50 cycles vertical and 15,625 cycles horizontal scanning lines. When I try to display NTSC and adjust the horizontal hold up to 15,750 cycles, horizontal frequency is disturbing by small interupts, i.e. there are misfires in the frequency with bright sparks in the middle of the screen. With 150k (R603) the 6CG7 might be overloaded. I have just the exact voltage values in the horizontal oscillator unit of the set asccording to the RCA manual.
But I have received now the complete Sams Photofact papers for the ctc-5 in jpeg-files. (Please PV me if you want it too.) In the Sams the schematics are more detailed and with different voltage values than in the RCA manual. Here are they (in brackets are the values of the RCA manual):

Pin 2 of the 6CG7: -15v (-27v)
Pin 3 of the 6CG7: 10v (5v)
Pin 6 of the 6CG7: 215v (235v)
Pin 7 of the 6CG7: -70v (-88v)

Pin 3-6 of the 6CB5: 6v (7.5v)
Pin 4-5 of the 6CB5: -30v (-40v)

One can see that the values of the Sams are lower than the RCA values. The RCA values are border values in my opinion. I would lower the resistance of R603 down to 130K or 120K to avoid overloading of the horizontal oscillator.

[Telecolor 3007]

Nice job, yagosaga. I sow the tv on your site. I'm lucky if I ever get my hand on an "R.C.A." CTC-11.

[yagosaga]

Originally Posted by yagosaga

I did it tonight. The readings of the test meters:
Start: b+ 371v, horizontal output current 210ma, high voltage 21kv ...
60 minutes: b+ 371v, horizontal output current 210ma.
No significant changes. ... The flyback was a little warmer after 15 minutes and very warm after one hour, not hot, estimated temperature appr. 50 to 55 degrees celsius.

Tonight I have checked the flyback of my PALcolor 708, the first PAL color tv set by Telefunken, which has nearly the same currents like the RCA CTC-5 (380 volts). After one hour the flyback was much more as hot as the flyback of the ctc-5. One can't touch the flyback of the PALcolor for a longer time because it is too hot! In comparison the ctc-5's flyback was really cold.
Both sets are operating with 380 volts in the horizontal output unit (anode voltage for the horizontal output tube), the ctc-5's current shouldn't extend 220 ma. The PALcolor has 260 mA horizontal output current. This indicates that the growing temperature of the flyback of the ctc-5 is in the normal range.

[yagosaga]

Today I have soldered an octal connection for the deflection yokes to operate the chassis outside the set (see photo). I tried to adjust the horizontal output current by turning the core inside the horizontal tuning coil (horizontal linearity). But I can't turn the core, it sticks. How can I loosen the core without destoying the coil? Here by us we do that with a special oil which is a mixture of oil and some kind of acid. But is this the right way for fixing such vintage devices?

[roundscreen]

Eckhard. turn the set on and run it for 45 min. The heat from the coil may break the core loose. I do not think you should put any oil on the coil. It may destroy it.

[NIPPERTHEDOG]

Wow I guess detweiler has a source for tubes and everythjng else in the father land. Did Europeans do Color TV later?? I know they made BW TV's earlier. No Early Color Euro TV are turning up on Eay. They must be very rare. Anyone got an idea as to make & models of early euros????????

[roundscreen]

Here are some pictures of my ctc 5 E. Two of them are off the dvd.
The other one is off the air. UHF ch 23.
I have been running the set at 114 vac 214 ma horz current for quite some time. The fly gets hot after a couple hours. But I can hold my hand on it and there is no wax dripping out of it.
The only problems I have had, Is a color tube go bad and the camera picks up lines. You can see them if u blow them up. I do not see the lines when I am watching it. Even if I am close to the screen
Sorry it took me so long. I caught some stupid flu, And I found my self A new gf.

[yagosaga]

Originally Posted by roundscreen

Here are some pictures of my ctc 5 E.

Thank you for that great photos of your ctc-5. Next time, when I have some hours in one piece, I will remove the chassis and do the adjustments. It is important to know for me that your set didn't get a hot flyback with 214 ma horizontal current.
BTW: I was worried nothing to hear from you such a long time. I hope you have no aftereffects of the flu.
Meanwhile I have got two Telefunken sets (A PALcolor and a PALcromat, both from 1967) of the first hour of color tv here into working condition. But I was dissapointed about the contrast range. Both sets have a small contrast range in comparison to other brands.