[Amps] Small Amplifier

[Dennis12Amplify at aol.com]

In a message dated 1/14/05 11:16:27 AM Central Standard Time,  
craxd1 at ezwv.com writes:

I want  to build a new small amplifier for those times when I really don't
>  want to heat up the shack with the 5CX1500A.  I have a supply of  4CX300's
> and sockets as well as 4CX250's and sockets.  I plan to  use two in  
> parallel.
> Is there anything to recommend one  over the other?
>
> David C. Hallam
>  KC2JD



Dave,
 
 The 4CX300's, (especially the 300Y's with their actual 400 watt  plate 
dissipation), utilize twist lock shakeproof sockets that provide  better anode 
cooling. The 4CX250's have a 250 watt plate dissipation but the  sockets for the 
250's are much cheaper and more readily available.
 Since very few folks have, or can afford to purchase, the twist lock  
sockets for the 300/400's, the new tubes available at the Hamfests and at other  
surplus sources are usually much cheaper, or at most no more expensive, than the  
250's.
 If you plan on building an amplifier head unit that you would  share between 
base and mobile power supplies, the 4CX300 would again be the  obvious choice 
because it would hold up to any road vibration much better than  the 4CX250.
 If it was me, the choice would depend mostly, if not  entirely, on if I 
already owned some good sockets for the  4CX300's or not.
 
 Regards,
 
Dennis O.