[Kenwood] TS-940S mod identification

[BSugarberg]

Hello Mike,

This was a kit offered by Inrad / International Radio Corp.,
which is now two separate companies:  Inrad and IRC.  Check
with Inrad for further details.

73, Bruce WA8TNC
================
Mike D. wrote:
> 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