No Access to the Ridge-Top Repeater
You are at a campsite 18 miles from the club's 2-meter repeater. The repeater output is 146.760 MHz, input 146.160 MHz (negative offset), CTCSS 103.5 Hz. You have a 5 W handheld with a rubber-duck antenna. You can hear the repeater perfectly and hear other stations checking in, but when you transmit, no one answers and a friend monitoring the repeater says she hears nothing from you. On the simplex frequency 146.520 MHz, you can talk to a station 2 miles away, but not to a station 12 miles away. Your radio's display shows 146.760 MHz, the offset is set to +600 kHz, and the tone is set to 100.0 Hz. The campsite is in a valley with hills in all directions; the repeater antenna is on a ridge. You have a magnetic-mount quarter-wave antenna and 20 ft of coax in the car, plus a fully charged spare battery.
1. What is wrong with the radio setup, and what would you check first?
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The two obvious programming errors are the offset and the tone. The repeater input is 146.160 MHz, which is 600 kHz below the 146.760 MHz output, so the offset must be negative, not +600 kHz. The CTCSS tone must be 103.5 Hz, not 100.0 Hz. With the offset set to +600 kHz, the handheld transmits on 147.360 MHz, nowhere near the repeater input; with the wrong tone, the repeater would not decode your signal even on the right frequency. You hear the repeater because receiving only requires the output frequency and no tone. Fix the offset to −600 kHz and the tone to 103.5 Hz, then try again. Also check that the radio is not in a lock or reverse mode and that the battery is charged.
2. After correcting the settings, you still cannot access the repeater. What are the likely causes and what can you do?
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The remaining problem is probably path and antenna efficiency. Eighteen miles from a ridge-top repeater is a long path for a 5 W handheld with a rubber duck in a valley. You may hear the repeater because its high-power transmitter and elevated antenna reach you, while your low-power signal cannot reach the repeater's receiver. Move to higher ground with a clear view toward the ridge, or use the magnetic-mount quarter-wave antenna on the car roof; the car roof provides a ground plane and raises the antenna. Check the coax and connectors, and try the spare battery. A directional antenna aimed at the repeater could help, but height and line of sight matter most. If you still cannot access it, use simplex or a phone. Do not use an illegal amplifier or transmit outside your privileges.
3. What operating practices should you follow on the repeater once you do get in?
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Listen before transmitting, identify with your call sign, and keep transmissions short. Use the minimum power needed and do not monopolize the repeater. Identify at the end of each communication and at least every 10 minutes during a contact. Yield immediately to emergency traffic and to any station with priority traffic. Do not use the repeater for business communications or for anything prohibited by Part 97. Follow the club's published offset and tone, and do not change the repeater's settings. If you are testing, say so briefly and avoid long unsupported transmissions. Courtesy on a shared repeater is part of good station control, and the control operator remains responsible for the station's proper operation.