Hi Jan,

Correct me if I am wrong but it appears the S041P is used
only as a "Limiter" in this circuit.  This can easily be 
replaced by some alternatives. Couple of them come to my
mind such as:

TA7061BP Limiter which is used in the ECSS module of NRD535
this part is obsolete but can be found in the market for about
$ 2.00

A popular part, Philips SA604AD, has a good limiter. It can also 
be used but has a lot more in it than just a limiter. And it is available in the market only in SMD package ( about $ 7.00 ).

Regards
Ahmet

=================================

Hi Ahmet ...

You may well be right. The problem is that the SO41P is described as a "low 
noise" version of this kind of chip, with low AM to PM conversion at low 
signal levels. Without a spec sheet on this IC (which I still haven't 
found) I have no way to compare it to the more modern alternates. So these 
may well work fine, but I have no way of knowing. If this wasn't defined by 
the designer as a "critical part" I wouldn't be concerned. However, for 
those who want to build one it would seem the Siemens chip is available. If 
anyone does build one, and is able to adapt it to a newer chip, it would be 
interesting to compare performance.

73s, Jan

==================================

S041P advertised as available:

http://www.vandijkenelektronica.nl/site/index.php?action=product&categories_id=14&products_id=441

==================================

