Difference between revisions of "HAM Repeater Offset"

Latest revision as of 19:31, 10 November 2015

The receive and transmit frequencies are offset for duplex communication on the repeater.

If a repeater output is on 147.300 the mobile would transmit on 147.900 and receive on 147.300. The repeater picks up the transmission from the mobile on 147.900 and simultaneously retransmits that on 147.300.

Band             Output Freq          Offset

6 meter           51.620 - 51.980      -500 kHz
                  52.500 - 52.980      -500 kHz
                  53.500 - 53.980      -500 kHz

2 meter          145.200 - 145.500     -600 kHz
                 146.610 - 146.970     -600 kHz
                 147.000 - 147.390     +600 kHz

1.25 meter       223.850 - 224.980     -1.6 Mhz

70 cm            440.000 - 445.000     +5 Mhz
                 447.000 - 450.000     -5 Mhz

23 cm            1282 - 1288           -12 Mhz
                 1290 - 1294           -12 Mhz

See your local band plan.

scanning

When scanning for repeaters you may hear an automated voice announcing a call sign and possibly some other information such as location or time. You can reference this information when looking up the repeater. You may also hear beeping as the repeater is using CW to identify. This is known as CWID.

plus and minus offset

If the repeater’s input frequency is higher than the output frequency, that is a positive shift. Negative shifts place the repeater’s input frequency below the output frequency.

PL tone

Private Line - some repeaters use this tone, which is below audio, for repeater access.