4 Feb
2026
4 Feb
'26
4:42 a.m.
Elston is presumably third party so maybe it was an older design?
On 4 February 2026 04:31:11 GMT, Tony Duell via cctalk <cctalk(a)classiccmp.org>
wrote:
On Wed, Feb 4, 2026 at 1:55 AM Peter Coghlan via cctalk
<cctalk(a)classiccmp.org> wrote:
I don't think germanium power switching
transistors enjoyed a long and
stellar reign. Maybe this acounts for the apparant rarity of this
version of the board? Or maybe their reliability was poor and they
were quickly superceded by the board version with the silicon transistor
as soon as that technology became available?
The only germanium horizontal output transistors that I've come across
are the AU101, etc, used in the Perdio Portarama portable TVs. They
were not very reliable (and a right pain to change in that set, the
CRT has to come out first...)
I am surprised there's a VT100 using them. Silicon horizontal output
transistors were well-known by that point, and a lot more reliable.
The VT52 uses a silicon NPN horizontal output transistor. The VT05
seems to have used at least 2 monitor PCBs, one of which uses the
2N3731 horizontal output transistor which is germanium PNP. But the
other version uses a silicon NPN transistor. So by the time the VT100
as introduced silicon NPN transistors were established in this
application.
-tony