[Amps] Plate choke explodes

[Drax Felton]

It was an Ohmite Z-50 choke that exploded the first time.  That's what Orr
Radio Handbook 23rd edition uses on its 6m amp.

 

 

 

From: Eddy Swynar [mailto:deswynar at xplornet.ca] 
Sent: Friday, April 12, 2013 9:35 AM
To: Drax Felton
Cc: amps at contesting.com
Subject: Re: [Amps] Plate choke explodes

 

 

On 2013-04-12, at 9:07 AM, Drax Felton wrote:









 

So I've tried two different plate choke designs on my 6 meter 8877 amp I'm
trying to build.   Both times the plate chokes have violently exploded as
soon  as I apply 5 watt or less RF input to the amp.

 

Any ideas what I did wrong? 

 

 

 

Hi Drax,

 

Sounds like a classic case of "resonant  plate choke" to me...

 

Did you ever couple the choke to a grid dip meter beforehand, to see where
its natural resonance(s) may have been...? Most likely there was one right
in the middle of 6-meters someplace, for it to have self-destructed so
violently...

 

~73~ de Eddy VE3CUI - VE3XZ