Jim M0BMU  

 

Published  a  design  and  made a working  system  ........  he  also  eliminated the  need  for  a complicated   drive  by using  complimentary   out put  devices  ... I don't know  who else  made such a thing .... ?

 

G.. 

 

PS ::  I vote  for  Jims  design   ! 

From: Clemens Paul

Sent: Wednesday, September 12, 2012 5:31 PM

To: [email protected]

Cc: [email protected]

Subject: Re: LF: Fw: LOST TRACK

>You  can  use a  class  E/D    amp  in linear , with  envelope  restoration  , that  maintains  the  efficiency  , s/n   >imd   is  about   35 dB .

 

To my knowledge the first description in amateur literature of an

EER (envelope elimination and restauration) PA (400W) was by DJ7AW in CQ-DL 4/2001.

It's still in service.

I have the article as pdf  (in German) and can send it to anyone interested in building such

a PA which is not an easy task.Therefore,as far as I know, only two such PAs have been built.

One by DJ7AW and one in South America (Joe?). 

 

 

73
Clemens
DL4RAJ

----- Original Message -----

From: Graham

To: [email protected]

Sent: Wednesday, September 12, 2012 5:17 PM

Subject: Re: LF: Fw: LOST TRACK

Mal,

 

Things  have  moved on a bit

 

You  can  use a  class  E/D    amp  in linear , with  envelope  restoration  , that  maintains  the  efficiency  , s/n   imd   is  about   35 dB .

 

The  Op structure allows for  up to  50% loss  of  signal   randomly  along the  time  line , ie  first 50% , last  50% or  randomly  distributed

 

Problem with  short burst is the  'average energy' level  , like a  radar  , huge KW peak  powers  but  only  watts  average power .....and  yes  , wide  bandwidth .

 

Detecting  a carrier  is one thing  .. to  recover  data is a much  more difficult  thing and requires  a higher  level of energy

 

G..

 

 

 Virendatenbank: 2437/5264 - Ausgabedatum: 12.09.2012