1980 Lionel #783 S.O.S Weirdness

[Smoke Stack Lightnin']

One of many tips I picked up in this forum was regarding the melt down of foam double sided tape and subsequent shorting of SOS boards in Lionel Fun Demensia tenders.  The SOS in my 783 Hudson (circa 1980, purchased NOS) never worked and I had assumed the board had so to speak, died on the vine, having never been out of the box.  For me, the lackluster quality of SOS and horn did not warrant purchasing a replacement but if I could fix it for free...  and sure enough when I took off the cover what was once foam tape- gobbaldy goop!  I slid a piece of cardboard between the chassis and board, put her in gear and soon heard her chuffing analog intermittent blasts of white noise (much like my wife if I spend too much time in the train room).  Now the weirdness.  There is a rectanular, thin piece of aluminum cut the same size as the board dagwooded as follows; the metal chassis, foam tape, the aluminum piece, a black wire with the end stripped about an inch in a half laid atop of the aluminum (not soldered), more foam tape, then the board.  The other end of the black wire (atop the aluminum) is soldered to one of the speaker terminals.  Oddly enough, the SOS sounds just as bad (normal) without the aluminum and black wire as with it, so I can't figure what it does.  I talked to Lionel Tech Support today.  Although the younger techs have heard the ancients speak of it, there is no hard data, Cliffs notes, flip charts, pictures, or computer files to reference something this old!  Come on guys, 1980, Boy George, The Thompson Twins, big hair.  It wasn't that long ago was it?  People are running Pre-War!  Anyway, can somebody tell me what the aluminum thing is and do I need it?

Thanks,

Rich F.  

[ADCX Rob]

The aluminum is an RF shield.  Probably not critically needed, but it may cut down on spurious RF noise from the pickups on the tender or other sources around the layout.

Rob

[Smoke Stack Lightnin']

Thanks Rob.  Wonder if we should let Lionel know!