[Boatanchors] BC-342 query

[Richard Post]

Just finished repairs/ restoration on a BC-342.  (Multiple problems, 
story and pix at:

<http://oak.cats.ohiou.edu/~postr/bapix/BC342.htm>

The unit is paint-labeled above the nomenclature plate as:

MFP
MWO 11-850-1-3 SIG. 27
  SPECIAL MOD.
  TB SIG.-213

Part of the note refers just to the Moisture Fungus Proofing and the 
Military Work Order.

My query is the meaning of Special Mod. TB SIG.-213.

 From the problems encountered, one wag suggested that this one was a 
test for the Depot repair folks, which they failed ;-)


Thanks for info,

Rich KB8TAD

<http://switch.to/BA>