[Amps] Alpha 87A Tubes 3CX800A7 and the 3CX P 800A7

[Larry P. Greenberg]

Jerry,

My 87A draws around 35 to 50 ma grid current for 1,500 watts out.  Before installing AlphaMax, sometimes it would get into the yellow.  Now, with AlphaMax it is more well behaved.  I don't know much about the 3CPX800 other than you can run higher plate voltage and the tube is rated for pulse service.  I am not sure how that applies to use in the 87A.  

Larry, WA9MAG




Message: 4
Date: Mon, 31 Dec 2007 11:26:02 -0500
From: "jsternmd" <jsternmd at earthlink.net>
Subject: [Amps] Alpha 87A Tubes 3CX800A7 and the 3CX P 800A7
To: <amps at contesting.com>
Message-ID: <003901c84bc9$f65674f0$4201a8c0 at dellxps>
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What would typical grid current be for an Alpha 87A running 1500w on 20
or 40m?  My 87A gets up to 105 ma (Yellow LED) at times (into a very low
SWR antenna or dummy load).  Is this normal?  WOuld the 3CPX800A run
1500w at a lower grid current?

73 de  K1JOS (Jerry)
CCA #11906
CRA #1777