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Old Yesterday, 16:53   #120
Hugh
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Age: 68
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Re: When does your Heating usually go on?

Quote:
Originally Posted by Taf View Post
Our earliest valve TV had 2 switches: the first turned on the heating elements to warm the valves, the second, operated a couple of minutes later, turned on the HT (High Tension voltages). This was to prevent cathode-stripping which ruined thermionic valves very quickly.

As I joined the RAF, thermionic valves were starting to be replaced by discrete transistors. A few years later we were up to our eyes in Integrated Circuits and logic boards.
Wow! That takes me back to the RA17s we used at RAF Digby in the mid-70s…
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