Amps
[Top] [All Lists]

[Amps] 3CPX1500A7

To: <amps@contesting.com>
Subject: [Amps] 3CPX1500A7
From: "Jim Monahan" <K1PX@msn.com>
Date: Tue, 13 Jan 2009 15:26:37 -0500
List-post: <amps@contesting.com">mailto:amps@contesting.com>
I'm using one in my AL-1500 at 3400 VDC unloaded.
As you can see in the description below, it is essentially
the same as a standard 8877 except the envelope is about
.1 inch taller to allow for higher peak voltages in pulse service.

73, Jim, K1PX

K1PX@msn.com

"Subject: RE: Tech Question 3CX1500A7 vs. 3CPX1500A7

I recommend using a heater voltage of 4.9 V, regardless of which triode
you employ (3CX1500A7 or 3CPX1500A7)

The 3CPX version is designed to be used as a pulsed amplifier in MRI,
scientific, and laser excitation applications. As an rf amplifier at
power up to 2500 Watts it is not necessary to raise the heater voltage
with this tube.

Running slightly under voltage will help increase tube cathode life. A
5% reduction is allowable for this tube provided it isn't being pulsed
to power levels above 2500 W.

The only difference in the two products is that the CPX version has a
longer ceramic envelope, allowing it to be processed to higher plate
voltage without external flashover. The cathode is identical in both
tubes, but we allow raising the heater voltage in one case for higher
peak power. The warranty is lower in total hours for the CPX version,
this fact may be a consideration you haven't addressed. 

I recommend the 3CX1500A7 for "normal" (non-pulsed) applications.



Best Regards,

Reid Brandon

Applications Engineer

CPI Eimac division"
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>