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2 Meter AM activation

Last week I went out portable and used 2 Meters AM. I was using an FT857D lower SSB tx and rx set to -50Hz and Upper SSB tx and rx to +50Hz. Using a vertical dipole I had a few qsos with good audio reports.

So I thought id do it again this Friday 10:00UTC on G/SP-015 The Cloud.

Has anyone else done 2 Meter AM recently?

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No, nobody has done 2m AM recently, at least not in my part of the world. :wink:
To make this authentic you should use a tube rig!

73 Heinz

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I have an old Ham Radio book. I think there are a few Tube rig designs in there. Might have a go at some point.

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There is a regular 2m AM net in the near of Edinburgh. But like the old and antique modulation scheme that is AM, the regulars use an old and antique bandplan that is no longer compatible with those in the 21st century! :slight_smile:

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Hmm curious! Freq/time? I may have a listen in sometime :slight_smile:

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Did you pre-arrange the contacts Dom?

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144.550. I’ve alerted for 9:00UTC using my intermediate callsign 2E0KIO

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Ahh ! You bring up memories of the “good old days”.
My first hilltopping adventures were with the portable/mobile rig of the day, the Gonset Communicator. 2 meters and 6 meters AM. Take a look at this, the portable/mobile VHF radio of the 1950s/early 1960s!
GonCom4
This photo is the “IV” model from the 1960s.
73,
John, K6YK

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If you are going to build an AM rig then it has to use plate modulation to do it properly. Valved audio amp into bigger valve modulation amp into damn big modulation transformer and thence some vapour cooled output bottles.

If two strong men can lift the modulation transformer then you can consider the TX to be QRP. :slight_smile:

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Going to post on a few Facebook groups like I did last time.

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M6KIO I can tell you are a true AM’er!
I had a visit to the Voice Of America transmitter site in Dixon, CA one
day, the tech on duty gave me a little tour. Their spare modulation transformer was in a wooden crate about the size of a small car, and
he said it weighed 6,000 pounds… I don’t know how many Kilos that
would be !
That transmitter ran 320,000 watts input with high level plate modulation!

73,
John, K6YK

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Good plan. There’s a new FB group - “Amateur Radio in Macclesfield” - which might prove useful. It’s had a swift and large initial uptake from amateurs in the area around The Cloud so would be an effective way of announcing your activity. Hope it goes well.

Well… 3 stations logged on AM, did try a S2S with @G6WRW but She was too low in the noise!

I know that AM isn’t efficient, more for warming up the coax. I think widening the ssb tx/rx from 50hz might help. Going to try a different antenna as the vertical dipole is a prone ro blowing over in the wind.

Not giving up on this mode just yet!

I’m a small bear of very little brain, what do these settings do on AM?

It was suggested on a Facebook group as AM is made up of a lower side band and Upper side band. I’m new to this mode and it’s all experimental and a learning curve.

I’m not sure it can have any effect or even is in effect for AM. SSB is understandable as you can offset the carrier oscillator frequency to the audio passband. But as AM has both sidebands so you would try to have a positive and negative offset at the same time and I don’t see how that can work. I’m happy to be enlightened.

My normal response to any item seen on a Facebook group is to question its voracity more than an article on Wikipedia but I’m just a miserable old cynic :wink:

This might be of use Dom @M6KIO

http://www.k6xx.com/ft817/ft817_am.pdf

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But FM worked perfectly🙂

An S2S would have been brilliant, maybe another time. Glad to get you in the log though!

What power were you using?