[Amps] 160m mosfet linear amplifier problem with ferrite cores

[sasas asasas]

And how can i repair this problem???

--- On Sat, 4/17/10, David Cutter <d.cutter at ntlworld.com> wrote:

From: David Cutter <d.cutter at ntlworld.com>
Subject: Re: [Amps] 160m mosfet linear amplifier problem with ferrite cores
To: "sasas asasas" <tzitzikas_ee at yahoo.com>, amps at contesting.com
Date: Saturday, April 17, 2010, 12:15 PM

You might consider imbalance in each side of the primary which will cause a net dc to pass, saturation and over-heating.  This may be rubbish but it could get others thinking along a different path.

David
G3UNA


> HI. i have constructed this linear amplifier 500w rms (2kw pep) (50ohm) with 12 mosfet irfp360, http://tzitzikas.webs.com/linear500w.jpg for 160m band.
> When i gave 3watts of driving r.f power, it gave to output only 190w at 106VDC (6A current). Two radio amateurs who have construct this linear claim tha it gives 500w
> r.f power at 110vdc.
> But when i tried to give 4watts of driving r.f power the ferrite Cores (43 material)
> of transformer T3 broken! Which do you think is the problem??
>