View Full Version : RFT Color 20, introduced in the German Democratic Repunblic in 1969


yagosaga
04-30-2008, 05:30 PM
Hi Folks,

today I got the RFT Color 20, the first East German SECAM color tv set, introduced in 1969 with the start of color television in October 1969. This color tv set is a solid state set with the exception that the early models had three EY51 for EHT rectifying, the later models had a selenium cascade.

The early Color 20s were fitted with a 23" Sovjet color picture tube, the 59LK3Z. Later models were fitted with the (West German) A56-120X or a Toshiba tube. The Sovjet crts were very unreliable, only of of seven which were exported to East Germany, was OK. The lifetime of these crts were estimated with appr. 1000 hours.

I have got a Color 20 with the Sovjet color picture tube. Before I switched it on, I measured the crt with the crt meter. Blue 0.4 mA, red between 0.2 and 0.3 mA, and green 0.2 mA. This crt was bad. A case for a brightener or a candidate for rejuvenating. I switched the set on. The picture was bright and brillant, with full colors. I could not believe it! Another surprise was revealed when I displayed the old U.S. videos: this Sovjet color picture tube, made in the 1960's, has wide gamut phosphors! It is not exactly what I had with the 21AXP22A, but they are not those yellowish green which we have with our West German color picture tubes.

Kind regards,
Eckhard

bgadow
04-30-2008, 09:53 PM
Were these sets sold only in East Germany? I would think this would be a set owned only by the most priviliged; great to see this survivor.

I don't know much of the history of that era in Germany, so I will ask...was trade across the east/west border very common? Did many folks tune in the SECAM broadcasts in W.Germany?

yagosaga
05-01-2008, 01:49 PM
Were these sets sold only in East Germany? I would think this would be a set owned only by the most priviliged; great to see this survivor. I don't know much of the history of that era in Germany, so I will ask...was trade across the east/west border very common? Did many folks tune in the SECAM broadcasts in W.Germany?

These sets were only sold in East Germany. They were for the public. A trade across the east/west border for private persons was not possible until the German reunification.

Only a few people in West Germany and in Berlin watched East German color tv. They have insert a special SECAM decoder in their color tv sets.

An older east German engineer told me today, that the Sovjets used their own wide gamut phosphors due to not paying licence fees to foreign countries.

Here are some photos from the set.

- Eckhard

zenithfan1
05-01-2008, 01:58 PM
Thanks for the pics Eckhard. Very interesting set, so different looking than what I'm used to. I'd like to work on something like that. Too cool!! I'm into Grundig-Majestic radios, I like the way the German stuff is made. Always an interesting design and the quality is hard to beat!

Telecolor 3007
05-01-2008, 03:29 PM
Here is another pic of the tv: http://home.arcor.de/guenther.mengewein/rdf50/rdt14.htm
The other tv (Colorton 3000) is the one after Telecolor 3007 was made. :D
Is that true that Color 20 had only 3 electronics tube into it?

yagosaga
05-01-2008, 05:25 PM
Here is another pic of the tv: http://home.arcor.de/guenther.mengewein/rdf50/rdt14.htm
The other tv (Colorton 3000) is the one after Telecolor 3007 was made. :D
Is that true that Color 20 had only 3 electronics tube into it?

Hi Telecolor 3007:

FYI: I do not have the schematics for the radio.

The very first generation of the Color 20 was solid state (with CRT as display).

Few later models had three EY51 as EHT rectifiers in cascade circuits. The next models had a selenium cascade for EHT generation.

More information (only in German) on

http://www.scheida.at/scheida/Televisionen_DDR_Color20.htm

Translated by Google

http://translate.google.com/translate?u=http%3A%2F%2Fwww.scheida.at%2Fscheida% 2FTelevisionen_DDR_Color20.htm&langpair=de%7Cen&hl=de&ie=UTF-8


- Eckhard