Shure UC2 Hand-Held UHF Transmitter
Circuit Description725C1044 (TK)
For JA frequencies, the Group switch has 16 positions, and the
Channel switch has 10 positions.
Power Switch and Mute Interface
When a transmitter is turned off, the PWRDN signal goes to logic low
on U303, pin 19. This immediately disables the tone key, and the power
hold circuit automatically kicks in to bypass the power switch. This is
followed by 500 mS of delay, and then the rf is muted and turned off.
The power hold circuit is also disabled at this point, and the transmitter
shuts off.
