Century IIIB Rate Filter Parts and Schematics

[PilotMike2004]

Hi,
I just traced an autopilot problem to my 1B440-2 rate filter. A screw came out
of the metal stand off, it slid down and shorted something out. For the time
being I made a bypass cable from connectors I ordered from Newark.com and the
autopilot functions but does oscillate sometimes.

The transistors on the 1B440-2 rate filter are marked with numbers that I cant
cross reference. There are only two types. Does someone know what the 2N or
MPS numbers are for the transistors on this board? Anyone have a schematic?

I found a schematic for the 1C388 amplifier on the US patent web page for
public download. Apparently EDO Mitchell did not patent the rate filter and I
haven't been able to find any info on it.

Mike

[Denny]

Make friends with some radioshop guy and get a copy of the rate filter
schematic... The exact part numbers do not matter as long as you know
the type, i.e. npn silicon transistor versus fet, etc... Get standard
replacements from DigiKey, Mouser, etc... The rate filter is likely
just a simple RC circuit to integrate the varying voltage over time and
smooth it out... Not a big deal to fix if you have some experience and
like to tinker...

Denny