Hi Folks. I have begun the repair of a Kriesler colour television and thought that you might like to come along on the journey. The patient is a 26” Kriesler Model 660-1, fitted with the 59-01 chassis.

For me, the first place to begin is with the power supply. No sense plugging it in and pressing the “Bang” button. So I removed the power supply and put it onto the examination table. Noticed only one new solder joint, The mounting hardware for chopper transistor had cracked, and the blue insulator washer had burned and cracked, (very common), see the pictures when posted. The blue degaussing thermistor was dry-jointed, but fortunately did not rattle. The blue thermistors are difficult to get, and are different to the white thermistors fitted to later chassis types.

I changed the main filter electrolytic cap. It read alright, but, it is forty-seven years old, and the set lives far far away. Besides, it would probably not survive the one-week test period before the set is returned. The surge limiting resistor to the cap had gone open. No cause was found. So I re-soldered any joint that looked less than pristine, gave the two pots a squirt, and put the supply onto the torture rack, (variac), and tightened the screws, (wound up the voltage).

No good. Turned out the control module was not working. Fortunately, the module is of the plug in type, and I had a working television of the same type. Very useful as source of known working boards and modules.

The little module gave me much trouble. It did not work, but I could find nothing wrong! Guess something is breaking down under voltage. So I threw a small handful of transistors and a thyristor at it, but still no go.

Ding. Round two. I dusted off the oscilloscope, printed out the pages of the, circuit description with waveforms, and soldered on some pieces of solder as test points to the board. I connected the isolation transformer, the variac, and the C.R.O. and tightened the screws. Hmm. All the waveforms in the Oscillator, Modulator, and Driver section looked good, as did the voltages. Even the drive waveform across the emitter/base of the chopper transistor looked good.

Oh well. I restored the 340V connection to the chopper and again applied the mains.
This time it worked and the seventy-five watt load lamp lit as the 155volt rail came on. Lamp running hot. Chopper running cool.

Conclusion.
1. Witchcraft ?
2. Black magic ?
3. Sorcery ?
4. After much thought, I believe a dry joint under the blob of solder attaching the socket to the module. I'm guessing pin No.2

Part two coming soon.

Wayne.

Amazing skills of deduction Warren. You’re a clever man!

I’m putting down my bet for black magic haha.

Thank you again!

Hi Labrat. Take a thorough look at the control module for dry joints, especially along the sockets. In fact, re-solder the sockets regardless.

I know from bitter experience that intermittent connections on the module will result in destruction of the power supply.

Photos submitted.

Photos uploaded.

Hi Wayne,
I would like to follow your "adventure" .... but my Google searching for a schematic came up blank.
Do you have a digital copy of it, or a web site ... ??
Cheers,
Ian

Hi Ian.
I've just sent two manuals in separate e-mails to you. They look to have been sent O.K.

Let me know how it went..

Wayne.

Hi Wayne,
Received both .... very clear, readable etc, thank you.
Had a quick look through them this morning and there is a lot of good info there ...
Will follow along ... good luck.
Cheers,
Ian

Hi Wayne,

Two phrases in your first Post caught my eye .... the "Bang" button ... and "it would probably not survive the one-week test period" ....

these both brought a smile to my face ...

Kriesler put a lot of effort into the service manuals and training. They had to, the TV was a complex but also a well developed design.

Since unlike Pye they didn't have their own service department they had to rely on the service trade for their reputation.

Teletales Part two.

Until I can get some parts and some time, please refer to these notes to continue the journey. Comments welcome.
.
January 2022 Notes and observations.

Note. This set is an enigma.This set appears to have had extremely little use.

Only found evidence of one re-made joint on the power supply board. No other re-soldering.

The E/W modulator diodes look to have been replaced. Given time, they ALL failed. Yes. Every one.

None of the usual points of weakness had had extra solder added to their leads. Just the original solder from the solder bath.

Power supply board. Dead. R111 2.2ohm, 7W open.
Tr120 insulator burnt, mounting hardware cracked.
Dry joints on control module socket.

Aerial selector switched seized. cleaned and lubricated.
Mains switch sticking. Operated until free.

Mains filter/fuse board. Replaced all three bad caps.

Deflection yolk. The initial alignment not set properly. Will not touch. It has been adjusted to compensate.

Intermittent vertical collapse. Dry joints on the scan panel.

Volume and tone controls dirty.

Extreme sensitivity. Just looking at it will make it trip. Cleaned around the Ultor, Set the B+ under load, think that cap C103 had something to do with with it.

Picture tube bad. Super-poor emission. Boosted the tube with my restorer, and now looks passable. Do not wish to go brutal on it. Not my set.

Retrace lines at the top of the screen. Replaced C658 100/50. Positive leg corroded away.

Numerous electrolytic caps have signs of corrosion on their exposed aluminum cases. Their capacitance measures high. Will have to check against another meter. If the same readings, will replace all, as they will be leaking.

Horizontal frequency off. Haven't been able to set as the set kept shutting down.

Snowy pic/tuning issues. Will worry about that later. Let's fix the canvas first before we draw upon it.

The capacitor across the two horizontal output transistors measured alright. Gott sei Dank. My only real worry, was to find a picture tube with a hole punctured through its neck underneath the yolk. I think that it was only the light green coloured tuning caps that gave trouble.

Will update as progress is made.

Wayne.

Wow! It’s one thing after another. I hope the picture tube stays good after the boost. I guess time will tell! Good to know it seems as though it’s had little use so this may be on our side.

Looks like there’s lots of little gremlins to sort out.

So strange that it won’t stay on!

Thanks for the update Wayne, as well as your time.

Given normal operating conditions those Philips CRTs normally last well.
But if the 155v output from the power supply isn't set properly the CRT heater is over-run and wears out quickly.
Very important to follow the instructions.

That may be why the over-voltage crowbar is tripping??

Tele-tales Part No.3

Time to get serious.

Since this set is so temperamental, I had to perform some actions without analysing with test equipment.

First I removed the complete scan board to get it under the gaze of my Maggy Lamp. I re-soldered anything that looked as though it could do with some solder. Especially the heavy, wound components using the solder as a mechanical connection.

Please note that the cathode of the over-voltage thyrsistor returns to chassis through a frame stiffening rail, that is also used as a de-facto copper track. Re-solder all the connections to the rail, even if it looks as though “all is right with the world.”

Anyway, I re-installed the board, set the B+ to 155V and discovered that vertical collapse no longer occurred whenever the board was tapped or flexed. The set no longer tended to shut down when any
“little change in load occurred” such as switching on or off, one of the guns, Red, Blue, or Green.

The loss of horizontal lock persisted. Adjustment of the frequency control was fine, and the picture would float by, but not lock.

Using the plug-in module CU 701 from the donor set restored line lock as well as somehow correcting the severe “S” shape to the horizontal scan lines. I will repair the set's own module later.

Now, I was able to see what kind of picture I could get from this, lovely Kriesler. I sprayed C.R.C. 2.26 (Blue Can), onto the pots, not forgetting the wiper arm connection to the board and began to adjust the basics.

Results. Not too bad. Still, it is relatively early in the repair process. This is not a rush job on a telly, of no significance, that will junked in a year or two.

Adjustments to height, width, scan correction, Picture centring, focus, grey scale, G2 adjustment, and convergence were made to see how how things were going.

The results look good to the non-technician, but the convergence will not adjust correctly, and the grey scale looks blue in one of the darker bars.

I have been super busy, but will try to get back to the set next week end.
One of the convergence controls is spotted in the position of correct
adjustment, and if I can, will swap it over with another of the same value.
If not, will juggle some resistor values to get the convergence to set is an area where the pot, (wire wound) is not damaged.

Hi Wayne

Loving your updates and I appreciate you're a busy family man. Glad you worked out why the set was being so temperamental in shutting off. Clever.

Thank you for taking your time and I'm so glad that you're getting there with the set.

Looking forward to seeing some pictures whenever you can. Take care!

Mark