[Amps] Orientation

[Steve Thompson]

Paul Higginson wrote:
> In message <003a01c5524d$f635af40$0301a8c0 at home>, Steve Thompson
> <g8gsq at ic24.net> writes
>> Paul Higginson wrote:
>>> In message <001f01c5522e$c2a08480$0301a8c0 at home>, Steve Thompson
>>> <g8gsq at ic24.net> writes
>>>> Having opened one up, the construction is such that it doesn't
>>>> matter a jot. Be sure to have a good support for the anode cooler,
>>>> though!
>> I need to correct myself - the tube I opened up was GS35, not GS23,
>> although I expect the internal construction is substantially the
>> same, and my comments apply.
>
> Thanks for the clarification Steve, anyone with further information
> please jump right in.
>
> I've heard from some sources that the structure of the tube can change
> internally as it gets warm / hot and that changes to the tuning is
> minimised by vertical mounting.
Can't see the orientation affecting it myself.

GS35 pics:
http://g8gsq.ic24.net/gs35g.jpg  pic of the grid mesh with a well worn
cathode underneath

http://g8gsq.ic24.net/gs35a.jpg corresponding surface of the anode.

This tube had lived a hard life (at someone else's hands!). The final straw
was a grid wire breaking and shorting to the cathode.

The heater is a small diameter coil, spiral wound and bonded to the
underside of the cathode metal disc. It's hard to imaging anything more
stable or robust mechanically.

Steve