Operating On AM!!

Some Basic Procedures and Guidelines

At times, we are all subject to mistakes, forgetfulness, and maybe even downright stupidity! Maybe I should say ignorance instead of stupidity, since I can't imagine too many hams to actually to fit the later case.

Also, there are those who are new to this exciting mode of operation that just simply need a little guidance with their rig and/or just want to know how to fit in with the traditional style of AM operators. There really is no "click" or group of esoteric AM'ers. Fitting in on AM, in all honesty, is not an issue. We all have our unique personalities and hang-ups. In my experience, past and present, AM'ers in general are very open minded and welcome any and all into a QSO.

If you are new, there are a few basics of the style you might want to abide by just to keep from being ruled weird! Even though no one would tell you that over the air.

Operating AM is really no different to SSB, CW, RTTY, etc., since they all require that we be aware of our operating parameters and etiquette.

AM Frequencies

Even though AM is a legal mode of operation on any portion of the voice spectrum, there is a gentleman's agreement of certain areas of each band set aside for the AM mode. At present, there seems to be an expansion of these areas, so I can't be too specific.
160 meters    1.880 - 1.900 mcs, 1.940 - 1.945 mcs & 1.985 mcs
75 meters     3.875 & 3.880 - 3.890 mcs
40 meters     7.290 - 7.300 mcs
20 meters      ? (I don't go there)
15 meters      ?
10 meters     29.000 - 29.100 mcs

Calling CQ

No problem! As many might know, sideband ops, for some unknown reason, do not tolerate CQ calling on 75 meter phone! I never understood that myself. On AM it is a common practice to call CQ as it always has been, on any band and mode.

Using a "Rice Box" or Solid State rig on AM

The term "Rice box" was adopted some years back for reasons I won't get into. It is not meant as a derogatory description of another operators rig. It's sort of like the term XYL for the wife. XYL is not intended to mean the wife is old. I still prefer to refer to my wife as YL, particularly if she's listening in!
Most solid state rigs that can operate AM have very good instructions in the manual for AM tuning and operating. Follow them! You might be surprised to find that your 100 watt SSB rig should only be operated at 25 watts on AM! In most cases, this is true and you better follow it or you will be replacing the finals very soon. A good rule of thumb is to tune the rig for full CW output, then drop the carrier level to one-forth that output before transmitting on AM. Adjust the audio level according to the manual or watch the output meter and adjust upwards until a slight forward bump is detected. You do not want to see a large forward deflection on the watt meter! Reports from others listening will help you fine tune the audio.

Using an Oscilloscope

Not required, but highly recommended.
I can't tell you how much help a scope can be. This really applies to any mode of operation. You will find that most AM ops use a scope to monitor their waveform at all times. As one AM operator once said, "transmitting without a scope is like driving at night without headlights"! This is so true once you get used to having one to monitor your signal.
Scopes tell you many things about the signal going out into the ether. First it tells you the amount of modulation you have. It is easy to detect 100%, under, or over-modulation. A scope can also tell you if you have any hum on your carrier, distortion or RF in the audio, and a general idea of the bandwidth of your audio.
Later, I will have a section on specific "how-to's" on using a scope.

Frequency Counter

Not required, but recommended.
In our present times, with a limited area of AM operation on the bands, a counter can help keep you from being griped at by an adjacent QSO. Some old transmitters will begin to drift up or down in frequency as you transmit. The counter will let you know if you need to make minor adjustments to the VFO as you continue to make your transmission. You can overdo it too. If you drift down 100 cycles, forget it! Now when you start getting a kc or so away from your original frequency, that's the time to bump the VFO back to where it should be.

Frequency Meter (spotting device)

Actually a freq. meter is not the same as a counter. A frequency meter will produce a weak RF carrier that you can hear on your receiver to use as a spotter so you can setup on a specific frequency. If for instance you have a schedule to get on 3.885 and no one is there yet, you have to have a way to zero beat the frequency to make your call. You could just transmit and watch the counter to adjust the VFO accordingly, although that's not a good operating habit. It would be much better to be right on, or very close (within a couple hundred cps) to your desired frequency as soon as you key the rig.
The military surplus BC-221 frequency meter is one of the best I know. You can find them at hamfests for $10 to $15! They have a very accurate analog dial and chart to get you right on the spot you want to be. I have mine coupled to the freq. counter for even more accuracy. Make sure you get one with a power supply unless you want to build your own.

Joining a QSO in progress

The main thing here is be on, or as close to the frequency as the rest of the guys in the QSO. You might find there is some spread of frequency between each of the ops in session. Pick one of them and zero beat their carrier with your exciter or "Zero" setting on your transmitter. Do this before ever transmitting and DO NOT tune your rig on top of someone transmitting! Either use a dummy load or move to an empty frequency at least 3 kcs up or down from the qso to do that. Most the time, if you operate within the same area of the band each time, you should not even have to re-tune. You can touch up the plate current, etc., on your first transmission! That's one advantage of the ole tube type gear. It's very tolerant of be off resonance for a short period of time.
When you join in, wait until a station ends his transmission and then transmit your call sign. If you are heard, normally the next station in order will acknowledge you and turn it to you when they are finished with their turn.

Give your call, your name and qth. Also most will want to know what you are using for a transmitter and receiver. If you are new, tell 'em! They will most likely welcome you and offer good advice if needed.

Keep your first transmission rather short just to make certain that everyone is copying you ok. Otherwise you might be "talking into the ashtray", or in other terms, nobody can hear a word you have to say!

"Ole Buzzard Transmissions"

The "Ole Buzzard transmission" is a term used to indicate one who makes a very long transmission with very little content of interest to the group in qso.
Make your transmission with good content. The AM mode is NOT meant to be formal, but when you say something, try to keep the interest level on the positive side! Laughing and joking are welcome, just as it would be in person. Hey, this is a hobby right? I can get plenty of formalities at work.

You will want to keep a notepad and comment on certain items of interest that others mentioned. Don't just say Ok on this and Ok on that and Ok on this. That's just a waste of time for you and everybody else waiting to get in.

Keep in mind that not everything everybody mentioned requires a response! If I said "well, I got up this morning and walked the dog", who really needs to let me know that they heard me say I walked the dog!!!?

If a question is directed to you or the group as a whole, respond to it. If there is something that has been mentioned of interest to you or the group as a whole, then by all means comment on it or ask some questions of your own.

As the group gets larger, try to limit your transmissions proportionately, and hopefully everyone else will too.

To Be Continued........

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