Had one just turn up. It's the 100-156 rack-mount BC624 rx in SCR522. There were 5 used in SCR 561/2/3 (aka SCS-2) ground-to-air dispatch system for 5 fighter squadrons. Man-o-man could we integrate systems in 1943!!! Make an offer on this clean twosome. Shipping UPS ground will be up there, the two are probably 40 lbs & are each in 8.5" rack-mount copper cabinets Marty