[Mldxcc] POWER TUBE Question

[H. Kohlmoos]

Dear Contesters and DXers:

Berylium oxide or berylia is known to have outstanding heat transfer 
characteristics and was at one time used for hybrid circuit substrates, as 
parts for vacuum tube envelopes and in other applications where heat had to 
be transferered.  It was thought that it would replace alumina because of 
this feature.  Not so.  The dust from machine working berylia is very 
toxic - deadly toxic.

Berylia must be worked in a closed atmosphere and the trimmings disposed of 
in accordance with OSHA regulations.  It is dyed PINK so that it can be 
easily identified.

Do the Russian tube makers use this stuff in their high power tube 
envelopes?  If not then their supplier has chosen a poor color for their 
tube parts.

73, Kit  --  W6ISO