[Amps] Size of Parasitic Chokes

[Mike Saculla]

I see 3CX3000A7 amps with no suppressor at all. How stable have any of you found this tube to be? Anyone have one take off on them with no suppressor? Or should I include one just to be safe?

Mike K6MDS


--Forwarded Message Attachment--
From: km1h at jeremy.mv.com
To: sub1 at rogerhalstead.com; Amps at contesting.com
Date: Thu, 15 Jul 2010 20:53:59 -0400
Subject: Re: [Amps] Size of Parasitic Chokes

The YC-156 doesnt use a socket and hasnt shown any need for a suppressor.
 
With a spectrum analyzer its rather easy to spot a parasitic and then design 
whats needed. Many of the big triodes are extremely stable. Tetrodes respond 
well to grid suppressors, adequate screen bypassing and with a Carborundum 
style plate suppressor.
 
I cant say what these big tubes are like on VHF but Id be tempted to build a 
rather big cavity for 6M to get around the output C problem. I believe that 
is used on the FM and TV frequencies.
 
Is it worth the bother?
 
Carl
KM1H