Hung,
Reading through the post on MX-3XX radios ....I don't know if you ever got a copy of the manual for your MX but if not just give the factory a call. TKM is in Scottsdale AZ. 1-800-233-4183. Kathy will probably answer the phone. Ask for Earl the Technician. He can fax or if you need a replacement it probably won't cost an arm and a leg. Nice people. This is a small company, not like calling King (give up).
Rex Krauklis
C-150L Member
Louisville, KY
