E1A

Band edges, ships and low-band power

Check that a sideband signal stays inside the band, and know the rules for 60 m, 630 m, 2200 m, vessels and forwarding.

11 pool questions1 on the exam

Syllabus: Frequency privileges; signal frequency range; automatic message forwarding; stations aboard ships or aircraft; power restriction on 630- and 2200-meter bands

The whole signal must fit, not just the carrier

Each row spans 6 kHz either side of the edge. Green side is inside the band, red is outside.

Your dial shows the carrier. USB extends above it, LSB extends below. Add the bandwidth in the direction the sideband grows and check that end against the edge.

USB: highest carrier = upper edge minus bandwidth
LSB: lowest carrier = lower edge plus bandwidth

RememberKeep the whole signal inside: move the carrier one signal width (3 kHz for a 3 kHz signal) away from the edge, into the band.

60 m is channelized: CW goes in the middle

Channelized 60 m: CW goes on the channel's centre frequency.

Channelized 60 m operation puts a CW signal on the channel's centre frequency.

2200 m and 630 m: power is measured as EIRP

Bars to scale. EIRP = equivalent isotropic radiated power: as radiated by the antenna, gain included.

Both limits are tiny and are measured as EIRP (power as radiated by the antenna, gain included): 1 W on 2200 m, 5 W on 630 m (except in some parts of Alaska).

Memory hook2200 m: 1 W. 630 m: 5 W. Both EIRP, not PEP.

Ships and aircraft: license rules plus the captain's approval

Aboard ship or aircraft: same license rules, plus the captain's say-so.

For a US-registered vessel the rules follow the amateur license, not a marine permit. The master or pilot only decides whether the station may run at all.

RememberAny FCC amateur license. Captain approves.

Forwarding: the originator answers

Relays that pass along a bad message by accident are not primarily accountable.

Automatic message forwarding passes a message station to station. A bad message that slips through is primarily the fault of the control operator of the originating station.

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Compendium articles on the ideas in this lesson, beyond what the exam asks.

Check what stuck

Practise the 11 pool questions for this group. Answers are shuffled, and every one comes with a one-line "why".

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