> On Apr 27, 2016, at 12:49 AM, Jon Elson <el...@pico-systems.com> wrote:
>
> On 04/26/2016 09:47 PM, William Donzelli wrote:
>>> What was the highest level of integration in a single envelope?
>> Perhaps Selectrons.
>>
>>
> There were also "Compactrons", 12-pin tubes kind of extending the 7- and
> 9-pin submini tubes.
> Some of them had at least 3 elements in one envelope.
European tubes are easy to evaluate in that respect because the letter codes
designate what's inside. I remember the EABC80 (not sure that's the correct
number), which is a diode plus double-diode plus triode. Intended application,
if I remember right, was FM detector (discriminator, double diode), AGC
detector (single diode) and audio preamp (triode).
paul
