[Boatanchors] tube type Y644

[wf2u at ws19ops.com]

The Y644 is a pulse rated 4CX250B. The relationship to the 4X150 is  
that it has the same pin-out/socket. The 4X150 is a glass air cooled  
tetrode with 150 W anode dissipation and the 4CX250 is a ceramic air  
cooled tetrode with 250 W anode dissipation. Generally, pulse rated  
tubes can be used in place of their standard counterparts, while the  
reverse is not recommended.

73, Meir WF2U
Landrum, SC

Quoting CLIVE COLLINS <dartaviation at btopenworld.com>:

> Good evening gentlemen,
>   Does anyone recognise the subject tube please and isanything known  
>  about its characteristics and in particular does it have an   
> equivalence to a 4X150?
>
>   Thanks in advance and please mail me direct to keep the reflector clear.
>   All good wishes,
>
>   Clive GW3WEQ
>
>   (tube type Y644?)
> _______________________________________________
>