Run a little morse code practice on your repeater. Start your own FM CW net. Have fun and upgrade! A transmit/receive switch automatically switches your HT to transmit when you send CW and returns you to receive when you stop keying. The MFJ-552 has a built-in speaker, volume control and great sounding true sinewave sidetone -- NO harsh keyclicks!
The MFJ-552 measures 4W x 1 1/4H x 3 3/4D inches. The MFJ-522 uses one 9V battery (not included).