Graetz Faehnrich color

[roundscreen]

Sorry if i sound stupid. I took a look at the power supply. No regulator.
It is interesting, Looks like there are two power supply in your set. One part of the power supply is connected to a transformer. The other part is connected directly to the ac line{220}. Does you set have a remote?
The beam current circuit looks like a brightness limiter circuit I see in sets here.
Brightness limiter controls the beam current so the picture will not bloom due to to much current to the guns. {to much brightness}.
When I get home from work tonight I will look at the schematics closer.
You set is complex and I like them. Thank you for posting the schematics.

Well I had the k part right on the set you are working on. Did you find what is wrong? Does the 33 volts that goes to the tuner go to any of the other circuits in the set?

[yagosaga]

Ed:

the Faehnrich was a very cheap set. All what is not absolutely necessary was omitted. Therefore I estimate it not as complex. The Philips color tv sets are much more complex, Saba also.

The Graetz color tv sets of the generations before had two line output transformers, one for high voltage with a regulator circuit (no shunt regulator) and one for the horizontal deflection.

The line output unit of the Faehnrich is designed like the b/w horizontal output units. In my opinion it is very similar to the GE portacolor. Perhaps a shunt regulator might not be necessary because the beam currents are lower then in the sets before. The CRT measured not good, but useable. But the phosphors seem to be very efficient. The good picture might not depend on high beam currents but on effective phosphors.

A wired remote control can be connected. No ultrasonic remote.

In the moment I have no time to work on the Philips K7. Xmas is coming and I have to prepare the Xmas services and a lot of presents for the family. Perhaps I found some time around midnight to make the measures at the luminance controls.

Eckhard

[yagosaga]

Originally Posted by yagosaga

In the moment I have no time to work on the Philips K7. Xmas is coming and I have to prepare the Xmas services and a lot of presents for the family. Perhaps I found some time around midnight to make the measures at the luminance controls.

Tonight I have disassembled the Philips K7 and measured whether the brightness and color controls are grounded. They are not. I have grounded them, and then I got a picture. The Zener diode for the tuner regulation voltage I have changed last week. The only failure which remains is no contrast control. But this I will do in the next days.

A web page about the Faehnrich is ready, see

http://bs.cyty.com/menschen/e-etzold...h2441color.htm

And in the next days a web page about an East German experimental color monitor will go online. Due to server troubles I could only upload the photos of this monitor, which is appr. 1960 and fitted with a 21CYP22:

http://bs.cyty.com/menschen/e-etzold...arbmonitor.htm

Eckhard