[Premium-Rx] Racal Ra 3702 (37XX) IF Filter module

[Brendan Minish]

Hello Folks

I had a couple of off list replies.

It seems that the optional filter module, is as I suspected a rare
beast!

My interest in this is that after some time and email exchanges Sherwood
engineering came up with a custom down-converter (from the 1.4Mhz IF)
for the fantastic SE-3 Synchronous AM detector allowing it to be used
with the RA3702. 
The RA3702 combined with the SE3 is by a long shot the best setup I have
ever used for tropical band dxing but it would be nice to be able to add
some filters that are a bit wider than the SSB filters for when
conditions permit.

I am already using the trick that allows for the same filter to be used
several times with differing BFO offsets to emulate PBT, this works well
with the 1K filter for tough SSB sigs but would probably work better
with a slightly wider filter in there. 
Of course when receiving AM with the SE3 one has continuously variable
PBT since it will track the carrier as you retune (slowly) 


My other interest in acquiring one is in part that I would like to add a
narrower CW filter, the stock one is 300Hz and seems to preform much
more poorly that the wider filters in the area of blowby. 
In a way though this is not so important since almost all CW is on the
amateur bands these days and my little K2 performs very well indeed as a
CW rig there.

The 1Khz and up filters are fine but in both receivers in my 3702 the
300hz filter seems to preform less well that the wider filters 


I would love to add 100Hz, 2(ish)K, 4(ish)K and 8k to the existing 0.3,
2.7, 3.2, 6 & 12 Khz filters, subject to availability of course! 

73's and thanks for the help 
.brendan EI6IZ