See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/homebrew/fredbox.
Although there are still a few AM nets on some bands, the mode has mostly been replaced by FM and SSB. This is a pity as in years gone by people "chanced" on amateur radio by listening on short wave. I well remember hearing amateurs on 160m AM many years ago. I remember copying G4PJ 4 miles away on a crystal set in the 1960s when he was on AM.
These days, people can no longer just chance on amateur radio. Our hobby has changed and the way newcomers "find" the hobby will be different. Modes like FT8 may be fine for working DX, but it is unlikely to be an introductory route for newcomers. As a person with a poor voice, I quite like FT8 and WSPR. At the same time, I am conscious that these modes cannot be ways in to the hobby.
AM had many advantages: gear was simple, ex-PMR radios were practically being given away and signals could be detected by very simple detectors. The simplest was just a diode detector. As I recall weak signals were better on AM than FM. Of course AM carriers could be a real nuisance.
Many today have never experienced AM, which is sad.
Even MW/LW broadcast AM is being phased out.
Several of my designs in the past were for simple AM transceivers. See my website at www.g3xbm.co.uk or my free PDF book for details.
When I first came on VHF, most activity was on AM. These days what phone activity exists is SSB or FM with AM quite rare.
In some ways, this is a pity. AM gear used to be able to be picked up very cheaply and homemade AM gear can be very simple. I have to confess that I am rarely on AM these days, preferring FT8 as my voice is poor. I come on 2m and 70cm SSB for activity contests and once a week on a 2m FM net.See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/vhf-am .
When I was first active, AM was the main mode on all bands. On HF this was replaced by SSB and, in very recent times, FT8 has become very popular. On the VHF bands most use FM, although there are fewer coming on just for a chat as there are now (free) alternatives on the internet.
Now I am not saying AM is brilliant, but the gear is often simple and low cost. There has been a growing interest in AM on bands like 160m, 80m and 10m. If you have never played with AM, you don't know what you are missing! At one time, ex PMR AM gear was practically being given away.
On 2m, the centre of AM activity is 144.550 MHz.
I get the feeling that most people have a dim view of AM, not least our national society, the RSGB. In my view this is totally wrong. Like other modes, AM has its place. Just listen above 29 MHz when 10m is open.
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/vhf-am .
Since I released my free G3XBM Project Scrapbook, I have already thought of some things that I have left out!
I also made a 100mW AM transmitter with very pre-emphasised speech and heavy clipping. This was extremely punchy and effective.
In the photo, the rig on the bottom right was a 10m 1W CW TX. It was my first experience of HF, with a loft dipole. Later, I made a 10m PA to increase the power. I think this was to 25W. It was far too much for me!
At the time, my 2m antenna was a hand rotated, 2 element, HB9CV in the loft, that I could turn from the operating position.
Sadly, I no longer have schematics for these rigs, but I shall add reference to these in the next edition, by which time I might remember more, HI.
It seems hard to think this tiny rig was designed and built so long ago (1974?). It was rebuilt a few years ago and still works. It must count as one of my favourite all-time rigs.
I would not recommend trying to exactly copy it, but use it as a source for your own designs. Some years ago, I know one club did a PCB for a version with a loudspeaker amplifier and loudspeaker. I forget who this was.
In its day it had several 100km QSOs handheld and even one of 160km to France handheld even though just 10mW AM. These days, most local QSOs are on FM. In its day, it was a very small rig and much smaller than commercial handhelds.
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/homebrew/fredbox .
With 10m again becoming a good DX band, it does not seem right talking about a simple cross-town natterer for 10m! Mind you 10m is often a daylight DX band and there are plenty of times when it is dark when the band is totally unused.
Derivatives of this simple radio might make an ideal 10m cross-town natterer. Just above 29MHz would be an ideal spot with plenty of space and very low chances of causing anyone else problems. This receiver has heard USA AM stations with just a base loaded whip on the car, although I would not recommend it for serious DX work.
In my mind I see a rig a bit like a tiny Heathkit Twoer (remember these?) with a tunable RX and crystal controlled TX. On a suitable PCB it could make a nice club project. Improvements would include an AF amplifier to drive a loudspeaker and maybe a very simple linear to bring the power up to a few watts of RF.
I cannot imagine the rig costing much more than £10-20. Put it another way, how many cups of coffee or beers will that be?
See https://sites.google.com/view/g3xbm4/home/hf-mf-and-lf/homebrew/10m-am-tenbox .
One of the pleasures of the last solar peak was hearing the USA AM signals just above 29MHz. One of the beauties of 10m is its size. With 1.7MHz of bandwidth all modes can be accommodated without issues including FM and AM.
It is some while since I was on 2m or 6m AM.
There has been something of a revival in AM, although AM should not be used on busy bands. There are AM nets on 160m, 80m and 40m. I am looking forward to again hearing 10m AM from the USA just above 29MHz.
See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/vhf-am .
Although I have not used AM recently, partly as a result of my poor voice, I can see the attraction of the mode. It lends itself to home brewing and in the past I have designed and made several AM rigs. At one time they were practically giving away ex PMR AM rigs.
The Fredbox and Sixbox are examples of AM rigs I have designed and made in the past.
Southgate News has announced the formation of an AM Amateur Radio Society.
My thanks to Steve G1KQH for pointing this out.
Before my stroke, I enjoyed going out in the field to see how far I could cover, especially over the horizon using QRSS (very slow CW) with PC decoders.
Much greater distances would have been possible, then my health got in the way. 😕
All the gear was home made. This was one of the attractions: all the gear was simple, including the test gear.
This is a field of experimentation open to everyone. You may find some ideas on my main website.
My XYL was looking in our loft for some pictures and came across my mobile logbook that I had not seen for over 7 years. I have never managed to get in our loft since my 2013 stroke.
In the logbook is my Fredbox QSO across the Channel with 10mW and a halfwave whip on 2m AM in 1976. This was one of my all-time best ever QSOs. See logbook page photo below.
Years later the Fredbox was revived and used for some local QSOs again.
See https://sites.google.com/site/g3xbmqrp3/vuhf/fredbox .
