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Go for the electric chair !!
----- Original Message -----
Sent: Thursday, September 29, 2011 6:27
PM
Subject: Re: LF: Wilkinson combiner
Thanks Mal
Hope you have success with this.
If reliability is key, consider using a three or four port
version. I use a 4 port version in my MOALFA amp. With more
smaller amps you don't need to push each individual amp as hard which is nice
during fault conditions or stormy weather. Never lost a FET on this
amp. Well to be truthful, I killed them all during the first test setup
when I melted my dummy load that had a faulty connection on the water
cooling...
I just noted Jim's comments and I agree with him about the
efficiency statement. My main motivation for creating my high power amp
was the lack of efficiency in my TX antenna system (poor vertical or big
loop). The final compromise was a big amp and a loop.
The smaller
multiple stages allows the use of less exotic ferrite materials (I use TV
flyback cores) and cheaper transistors etc etc etc...
My amp has two
settings:
Stun (1KW) and KILL
(2KW)
:-)
Scott
On 9/29/2011 10:49
AM, mal hamilton wrote:
Scott
A nice neat job, tidy build
.
mal
----- Original Message -----
Sent: Thursday, September 29, 2011
4:30 PM
Subject: Re: LF: Wilkinson
combiner
Hi Mal
This was the original 2 port design I used to
combine two 500W amps. Works fine. Steve, VE7SL uses this
design done as well for his 1KW amp.
http://www3.telus.net/sthed/argo/wilk/
A
possible benefit is that the combiner elements provide very good low pass
filtering so you may not need a separate filter. Make sure the
LO chain of both amps is shared.
This design should be fine for
your application and won't need ferrite.
73
Scott
VE7TIL
On 9/29/2011 8:34 AM, mal hamilton wrote:
Components would need to be hefty to handle two
amps each one several hundred watts to get 1w erp on 137
Maybe the decca approach is better with just a
transformer, 3 primary winding and one output winding, their method
handles 1.2 K/watts without any strain.
g3kev
----- Original Message -----
Sent: Thursday, September 29,
2011 8:46 AM
Subject: Re: LF: Wilkinson
combiner
Scott
Two amplifiers to combine to one output.
2 ports in 1 port out
de mal/g3kev
----- Original Message -----
Sent: Wednesday, September 28,
2011 10:17 PM
Subject: Re: LF: Wilkinson
combiner
Hi Mal
How many ports?
I personally
prefer air core coils but iron dust work better than ferrite for
this application. Amidon #3 is the best.
Once I know
the number of ports I can give you
values.
Regards,
Scott
On 9/28/2011 10:59 AM,
mal hamilton wrote:
LF/MF Is anyone using a
wilkinson combiner with LF amplifiers and if so what are the
optimum paramaters for ferrite cores/windings
73 de mal/g3kev
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