Detail from Fleet command's "working " communicator. These had a bird chirp sound effect, which chirped for about 4 to 6 cherps and then shut down. The leds would blink untill the lid was closed. Roughly 10 years later all this was reduced to a micro switch, and a board 1/3 the size you see here, and these later boards had digital sound playback of the real com beebs and some with voice playback from the show. "Enterprise here." "How many to beam up." were on some.