2 Meter AM activation

On the Bands
21

30W on AM and FM

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But every airplane uses VHF AMā€¦
cu 73 Maritn

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Yes, but for a very special reason where safety is more important than efficiency.

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We ran an annual AM day in VK for a few years. It led to contacts being made on 2m, 6m and 40m. It was very interesting to hear the clear quality of some familiar rigs like the ft817 on AM. On HF it created nostalgia for ex AM ops, due to the unique sound of selective fading on double sideband AM. The timing was April 1st but that was not intended or taken as a comment on the mode.

A few tips may be helpful. When using multimode rigs for AM, like the familiar qrp rigs we use on ssb and cw, remember that AM has a peak envelope power that is 4 times the unmodulated carrier power. Donā€™t attempt to increase the power of the carrier to more than a quarter of the rated ssb power. Some rigs produce AM by transmitting a double sideband signal with injected carrier. Avoid the sound of overmodulation and distortion by keeping the mike gain to a level where the output power increases slightly with modulation, it should be about a 25% increase in output power when fully modulated. Power meters donā€™t show the pep.

AM sounds exactly like properly tuned ssb, which will shock the majority of ssb users, who always tune ssb signals at about 100-200 hz higher pitch than it should be. But due to the steady carrier, AM on vhf sounds stable and pleasant. Everyone should try it occasionally. And you get to use the vfo knob on your vhf radio. More discovery!

Have fun.

73 Andrew VK1DA/VK2UH

2 Likes
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Iā€™ll have a into the settings and have a mess around soon. Wouldnā€™t mind trying AM on HF too.

73! Dom M6KIO/2E0KIO

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What part of the country are you in?

I will be activating a couple of summits around the South Pennines over the next couple of days. I will only have handhelds for 2m (so FM only) but will also be running 20m & 40m from most of the summits using an Icom 703 (which I believe does have AM capability).

Iā€™m more than happy to give it a go from one of the summits if you are around & we can find a band that works between us?

Likewise if anyone else wants to try it then let me know. My planned activations are all in that alerts.

1 Like
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I live in Stoke so The Gun and The Cloud are my closed summits. Unfortunately Iā€™m on night shift this week. Hopefully Iā€™ll be out portable soon.