Use of Diodes in Filters??

[Magnus Danielson]

>>>>> "RH" == Rob Hukin <robh at epunix.biols.susx.ac.uk> writes:

 >>> One trick one may play with the diode is to stack multiple of thems
 >>> such that you migth get better signal to noise ratio (less noise that
 >>> is). An extreme case of this is found in the EMS Hi-Fli where the
 >>> phaser section contains a stack of 20 diodes per AP filter, there is a
 >>> total of 12 in the Hi-Fli which results in just 240 diodes for the
 >>> core phase block itself.

 RH> Maybe i'm missing something here, but isn't there a relationship between
 RH> the number of diodes in the ladder and filter order? So, in the EMS filter,
 RH> diodes D3, 4, 5, 10, 11 and 12 maybe to do with matching/better SNR, but
 RH> the rest and required to get a 4-th order response?

What do you know... being a bit tired I missed out some finer details
of the question...

Hmm... those top 3 diodes in a row will act as a 3R termination of the
RCRCRCRC ladder. This will give a diffrent frequency response than
having just one. I haven't had time to analyse those details since I
got the schematics...

If I only hade NAPPE2 up and running...

Cheers,
Magnus