Uniden MHS135DSC English Owner's Manual - Page 18

Making a Transmission Select the channel you want to transmit on, then press and hold the Push to Talk button. Release the Push to Talk button when you're finished talking to let the other party respond. xx To prevent stuck microphone problems or situations where the Push to Talk button is pushed accidentally, the radio limits your talk time to 5 minutes in a single transmission. xx For the best sound quality, hold the microphone about two inches away from your mouth. xx See the channel lists starting on page E-23 for a list of receive-only channels. Changing the transmission level In most situations, 1 W transmission power is all you need. If you find yourself far away from other stations and have trouble getting a response, you may need to increase the transmission power. If your radio is powered by a Li-Ion battery, you can press and hold the BOOST button to transmit at 6 W. Alkaline battery power boost is limited to 2.5 W. To increase the transmission power in increments: 1. Select the channel you want to transmit on. 2. Press ENTER-H/M/L to switch to the next transmission power level (for example, from 1 W to 2.5 W, from 2.5 W to 6 W, or from 6 W back to 1 W). 3. The display shows the new transmission power as 6 W, MID, or LOW. The transmit power remains at the new setting until you change it again. ## Note: Don't forget to change the transmission setting back to 1 W when you move close to other stations. Some channels (for example, channels 13 and 67) limit the transmission power to 1 W. When you tune to a limited-power channel, the radio automatically switches to 1 W. See the channel lists starting on page E-31 for a list of power-restricted channels. Digital Selective Calling Features What is DSC? Digital Selective Calling (DSC) is a standard that allows you to call other stations using their unique identification code (the Maritime Mobile Service Identity or MMSI number), just like you would call a phone number. To call another station, just enter that station's MMSI number and choose the voice channel you want to talk on. The radio uses channel 70 to transmit your MMSI number to the other station along with the voice channel you requested. If the other station accepts your call, both radios automatically switch to the requested voice channel so you can talk to the other station. DSC provides a system for automated distress calls. At the touch of a button, the radio can transmit your MMSI number, the nature of your distress, and your current position based on data from your GPS receiver. The radio repeats the distress call every few minutes until it receives an acknowledgement. The DSC standard dedicates a VHF channel-channel 70-to digital transmissions only. Since digital transmissions require less bandwidth voice transmissions, channel 70 E-14 Uniden MHS135DSC Radio Owner's Manual