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RE: Used Bellows for BE FM-30T
To: CRTECH <crtech@crtech.org>
Subject: RE: Used Bellows for BE FM-30T
From: Scott Todd <stodd@kloveair1.com>
Date: Mon, 19 Nov 2018 14:19:09 +0000
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Thread-topic: [CRTech] Used Bellows for BE FM-30T

It’s the combination of the DC plus high RF circulating voltages in the cavity.  It’s especially bad in the 35kW units.  Keep the plate voltage below 12kV and it’s less likely to happen.

 

Scott Todd

 

From: John Stortz [mailto:ka4flx@gmail.com]

I worked on an FM-30T before retiring. The bellows used to get what used to appear to be random holes burned thru the thin bellows copper. BE was aware of the problem but said they didn't know why it happened.

References: Re: Used Bellows for BE FM-30T
(John Stortz <ka4flx@gmail.com>, 19 Nov 2018 06:26:29 -0000)
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