[Kenwood] TS-940S mod identification

[Mike D.]

I have a newly acquired TS-940SAT and discovered a mod(s) with an extra
filter. I haven't been able to find any information about it. 

It has two 400 Hz Inrad filters (Nos. 1085 & 1404). There are two small PCBs
added with "IRC-10" marked on each board. There's an added Inrad filter
mounted with tape vertically just behind the front panel. I can't make out
the part number, but it's for the 455 Hz IF. 

This rig also has the YK-88A-1 6 kHz AM filter and a YK-88S1 2.4 kHz SSB
filter. 

Does anyone have any information on this mod? Thank you.

73 de Mike, N9BOR
A-1, FISTS, JARL A-1, SMC
http://www.n9bor.us
http://www.k9ya.org

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