[Premium-Rx] Marconi LP Filter

[Richard M. MC Clung]

I just received a really nice 300KHz LP Filter. It is in a metal case
that has spring loaded thumb screws to attach it to something else.

It is passive with a BNC chassis connectorfor input and a short cable
with BNC connector for output on the rear of the chassis and a switch
to select or bypass the filter on the front panel.

It is 10 inches long X 2 3/4 inches height X 1 5/8 inches wide.

The chassis data is:

MARCONI INSTRUMENTS LTD
300 KHZ LOW PASS (B) FILTER
TK 2095
TYPE NO 52095-014P
BATCH NO J 173311
TO CCIR RECOMMENDATION NO 339/1

The PCB data is:
PM3
44816-108
300KHZ LP

I put it on the spectrum analyzer and it is flat from 0 KHz to 300KHz
with a 2dBm insertation loss is 36dBm down at 308KHz and 50dBm down at
319KHz.

I'd like to use it ahead of my VLF RCVR's and would like to get any
documentation on it.

I'd also like to retune it to 500KHz. It has adjustable inductors in
it.

Anyone ever see one of these or have any doucmentation on it?

RICH  WA6KNW