Theodore R. McElroy
Boston & Chicago

World's Champion Radio Telegrapher
77 WPM in 1935, Ted typed at 15Ø WPM

194Ø ARRL Handbook ad - page 524 CP-810 CP-810 CP-810 CP-810
Telegraph Apparatus Company
Hole in the Wall Bug

Model          CP-81Ø
Production Run 1936 - 1938
Base size      4" X 7"
     finish    Chrome
Aquired        March 2ØØ1
Speaker Case Speaker Case Speaker Case Speaker Case
Telegraph Apparatus Company
Speaker & Audio Amp

Production Run 1936 - 1938
Base size      4" X 7"
     finish    Bakelite
Aquired        March 2ØØ3
1938 1938 1938 1938 1938

Model          Deluxe Model Mac Key
Production Run 1938
Serial Number  347
Base size      4" X 6.25"
     finish    Deluxe Marbelite
Damper         Bent I
Aquired        Febuary 2ии2
Sold           September 2ии2
  to           KG4CYO
The dash contact support is broken and missing. The early (thick) stabilizer or dot-spring pre-tensioning device, used to prevent "split dots" (Vibroplex), or "Pffft" (McElroy), is missing. The pendulem return spring. A better view of the Marbelite.
Model 100 Model 100 Model 100 Model 100
Stream Key

Model          1ØØ Amateur
Production Run 1942
Base size      2.5" X 4.5"
     made of   Black Plastic
               Also in Gray or Red
Aquired        March 2ØØ1
an e-mail from The Morse Reflector warns...
I had a black one in my display case for years and one day I forgot to put up my tent and the sun heated the case and the key melted... OOOOPS !!!
Model 100 Model 100
Stream Key

Model          1ии Amateur
Production Run 1942
Base size      2.5" X 4.5"
     made of   Cast Iron
Aquired        March 2ии1
Model 300 Model 300
Stream Key

Model          300 Deluxe
Production Run 1942
Base size      2.5" X 4.5"
     finish    Chrome
Aquired        June 2ии1