Photos uploaded to Post 14.

Tele-tales. Part 4. 20-2-2022


Well friends, the set is almost done, and the end is in site.
Before I tell you what is left to do, I shall tell you about what I have encountered.

First I had to give the picture tube another “kick in the groin” with the tube tester. I just could not get the picture to track well enough from low to high brightness levels.

The tube read better but the red gun was prone to comet tailing, and green gun had too much inter-electrode capacitance. When the brightness was advanced, the green background would disappear as the whole screen would become green. Also when at a moderate brightness the green's beam would be de-focused.

After a couple of days, the tube behaved much better. Perhaps some particles tell off the electrodes of the guns. Much better now, and set up a treat.

There is some blooming, but not enough to warrant fitting a new trippler.

There was still quite a bit of random issues that were sorted out by
re-soldering ALL the pots, not forgetting the wiper arm to solder tag rotating connection on each. the connectors of each module were re-soldered and C.R.C. applied.

Alignment of the 4.43 MHz oscillator was was way off. I can't imagine how the burst signal was able to lock it.

Now back to the present. Still to go.
The set needs a TBA 240B ic. and the power switch is still playing up. Then a good long soak test. The set no longer shuts down whenever stared at, nor when tapped with the end of a calibrated screw driver. It looks remarkable for its forty-seven years. A pleasure to view.

Anyone able to help with a TBA 240B ?



Wayne.

Hi Wayne, I’ve put the call out for a TBA 240b on the Facebook forums as well. I’ll let you know if I have any luck!

Great post.

Really good trouble shooting skills.

After seeing the photos, I'm starting to feel things about K-(5)9 I haven't felt for years!

G'day Labrat.

Those K59 (insert-revision-number-here) sets really do it for me. The cabinets were so (for the time) "stylish" The floor models were bigger than my mum and dads couch. In the early 90's they were fish tank conversion fodder which was a great shame. Apparently the 59-3 was available with a "Pong" (the old TV game) module! I'm not sure what device they sold to manipulate the "bat' though.

They were the first TV I can remember with "touch control" which, from memory, was a pain in the as% when the paint wore off the buttons and it didn't want to play anymore.

The tripler blocks (no idea of coorect speeling) were prone to failure as were the EHT caps. Hissing and arching all over the place. The SMPS loved to go tick, tick, tick too when there was a dodgy feedback or an "overload" somewhere.

You're lucky to have such a "sexy" set. Can you post cabinet photo's?

P.S I'm not a technician, just a hobbyist, and I love plugging them in and hitting the LOUD BUTTON..... run up slowly on the variac. Where did my carefree youth go?

Cheers, Andy

I find running them up on a variac will still result in smoke and loud bangs, sometimes from the variac as well!
A much better and relaxing way is two 75 Watt incandescent globes in parallel, wired in series with the mains, then fire up.
If globes remain at full brightness switch off you have a major problem.
And thus avoid destroying new and expensive components. Heart failure and temporary blindness.
JJ

Following this really bring back some memories.
I've lost track of how many triplers replacements and power supply rebuilds I did back in the 70's on 59-1 Krieslers.
They produced the best pictures of all the crop back then and were nice to work on.
Lovely cabinets also.
Rejuvenating the CRT's was very hit and miss and didn't last very long unfortunately.
One thing to watch is the capacitor across the line o/p transistor.
If it has two in parallel be afraid.
If one goes o/c the EHT goes way up and punches a hole through the CRT bell.
The solution was to fit a single 11nf cap in place of the two.
It was a green one if my memory serves and if it went o/c the line o/p transistor failed immediately with no possibility of CRT damage.