| Part | Function | |------|-----------| | On/Off Volume Knob (top left) | Rotate clockwise to turn ON and increase volume. | | Channel Selector Knob (top right) | Selects 1 of up to 6 preset channels (depending on model: SP10 = 1 or 2 channels typically; SP50 = more). SP10 is basic: 1 or 2 channels via a toggle on top or side). | | PTT (Push-to-Talk) (left side) | Press to talk, release to listen. | | Monitor Button (below PTT) | Opens squelch to check for weak signals or adjust volume. | | LED Indicator (top front) | Red = Transmitting; Green (if equipped) = Receiving/Busy; Blinking = Low battery. | | Battery Contacts (rear bottom) | Clip onto the battery pack. | | Antenna Connector (top center) | Screw-on male SMA or BNC (depending on version). |