[Amps] PIN diode mods

[Craig]

Most of the early PIN diode mods came from the information and articles 
by Ulrich Rohde  N1UL.

The PIN diode mods were mostly for 2nd order  IMD  problems. There were 
claims for  some minor improvements in blocking and 3rd order dynamic 
range. However i seem recall most of the mods applied to low end radios 
like the TS450 and TS50 which suffered  badly from  2nd  order IMD  in 
places like Europe. I also seem to recall  that Signal One started 
promoting the supposed advantages of the HP PIN diodes in the Mil 
Packaged IC-781.

 Maybe  Ulrich with his well respected HF credentials and his vast 
experience with collocated HF transmitters and receivers in military 
markets became  the main   focus   for all his  measured  improvements.  
The data measured  with very  wide spaced high 3rd order intercept 
points may be valid using  better PIN diodes in  such a severe RF 
environments. Only he could answer these questions.


Craig
VK3HE