Quote:
Originally Posted by 1100 man
Well, this has proved to be an interesting thread! Considering transistor radios only came on the market in the late '50's, I'm amazed that there seems to have been quite a few all transistor TV's in the early '60's.
Cheers
Nick
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I think the first or one of the first all transistor TV's was the Philco Safari in 1959 :
http://www.tvhistory.tv/1959_PHILCO_SAFARI_H2010L.JPG
Then in the early 1960's many types appeared from Sony & Sanyo etc.Yet often, these still had vacuum tube EHT rectifiers.
One of the big issues that slowed this down was not the high frequency capable signal RF transistors, but HF capable germaniums that could handle a moderate amount of power. Specifically the H output transistor which needed a high fT, low storage time and high VCE max etc to switch off well eough and quick enough for H flyback.
To a lesser extent the video output transistor was also a challenge in 1959.
In American sets the mainstay for the H output transistor was the 2N3731 and it had a companion damper diode. The AU series in Europe had rough equivalents.
For video output, Mullard had the AF118 (also affected by tin whisker disease) and the Japanese had the 2SA358.
The first silicon transistors to appear in these early portable TV's in the late '60's were in the video output stage, and the H & V output stages.