[cctalk] Re: Z80 vs other microprocessors of the time.

[Paul Koning via cctalk]

> On Apr 22, 2024, at 7:03 PM, Chuck Guzis via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> On 4/22/24 14:34, dwight via cctalk wrote:
> 
>> For those that don't know what a UV(UX)201 was, it was most commonly used 
>> for audio amplification in early battery powered radios. These used a lot of 
>> filament current, not like later miniature tubes.
>> They had a UV(UX)200 tube for RF detections that worked better as a grid 
>> leak detector, I think because of less cutoff voltage needed as a detector.
>> The A series used a better getter and lower current filament ( one or both? 
>> ) but still used a lot of filament current.
> 
> I've long considered it to be an interesting coincidence that the
> filament voltage of the UV201 was 5V, just like much later TTL logic.

What about the coincidence that a lot of today's logic runs on 3.3 volts, just 
about the same as the first generation of IC logic (RTL).

> Folks don't recall that RCA was formed to get around a patent issue on
> the basic idea of a triode.

Interesting!

        paul