EME OPERATING PROCEDURES FOR 432 AND ABOVE BY G3SEK

1. Why? EME signals are often weak and fading, so we cannot always hear each other. To help us to make more QSOs, we need some agreed operating proc.

2. Minimum QSO: The definition of a minimum valid QSO is that both stations have copied all of the following: 1.Both callsigns from the other station, 2.Signal report from the other station (or some other previously unknown piece of information, e.g. the other station's Locator grid), 3. R from the other station, to acknowledge complete copy of 1 and 2.

3. CW speeds: The recommended sending speed on 432 MHz and above is a letter speed of 15-20 words/minute, but with extra space between letters so the word speed is only 12-15 words/minute. This helps to prevent individual letters of Morse code being broken up by rapid libration fading. Leave clear pauses between letters, and also between words or callsigns. Do not change speed. Do not send very slowly - it is harder to copy!

4. Signal Reports: On EME, do not send a signal report until you have copied both callsigns completely! Valid signal reports for 432MHz and above are: T (Not used any more) [Proposed change - T should be removed from the standard procedure. Almost nobody uses it, and it is too easy to confuse with M or O.], M Very weak, marginal copy but complete (M is valid for a QSO on 432MHz and above), O Weak, difficult copy but complete. Leave clear pauses between letters, so there is no possibility of mistaking M and O. RST - not the same as on HF. Typical EME RST reports include: 339 Stronger than O but still quite weak and difficult copy; 449 Stronger than 339, almost complete copy; 559 Very strong (for an EME signal), complete copy. Other combinations are of course possible, for example: 549 Complete copy but not "S5", 349 "S4" but difficult to copy, etc... Remember that RST is more difficult to copy than M or O, so using RST can be a risk in skeds and initial QSOs. Some stations do not like to use RST in contests because it takes more time.

5. Skeds:
5.1 Skeds Coordination Service - Most beginners start with skeds, and there is a highly effective world-wide skeds coordination service to arrange skeds for people who want to work new stations. If you want skeds, contact one of the skeds coordinators via the 14.345 MHz EME Net or at the e-mail addresses at the top of every Newsletter. You can of course arrange your own skeds, but do not use frequencies on or below 432.070 MHz and 1296.070 MHz. Reason: these frequencies are used for coordinated skeds, and there may be extra skeds that are not in the Newsletter.
5.2 Frequency - The first-named station in the skeds list transmits first, exactly on the agreed frequency for the sked. The second- named station also transmits exactly on the agreed frequency for the sked. This is the existing procedure. It is simple, and it works well enough. The only possible error for the transmitting station is in setting the frequency accurately. The receiving station tunes to compensate for Doppler shift, and for frequency errors at both stations. Another proposal is that the transmitting station compensates for Doppler shift by pre- calculation. This is much more, with the possibility of making mistakes. This is a big disadvantage for beginners on EME, who are the people who make most use of skeds. The receiving station still has to tune to compensate for the frequency errors at both stations, so little is gained. The increased risks and the extra complication seem to be greater than the possible advantages.]
5.3 Time periods - Time periods are used for skeds, because the other station may not be copying at the end of a transmission, and may not know to change over. For skeds on 432 MHz and above, time periods are 2.5 minutes for each transmission, synchronized to UTC (+/- 2 sec maximum error).
5.4 Example sked QSO - Skeds list says: 432.045 2300 DL9KR- K2UYH; DL9KR sets his TX frequency to exactly 432.045 (using an external frequency counter, not the frequency display on the rig). K2UYH does the same. Initial transmission Exactly at 2300:00 UTC, DL9KR starts to transmit: K2UYH DE DL9KR (pause) K2UYH DE DL9KR K2UYH... This continues until 2302:30 ... DE DL9KR K. Further transmissions - procedure depends on what has been copied. ? Copied nothing at all, or not copied both callsigns complete then First 2 minutes - transmit both callsigns. Last 30 seconds - do not transmit! ? Copied both callsigns COMPLETE, but no report then First 2 minutes - transmit both callsigns. Last 30 seconds - transmit report: M M M = difficult copy, or O O O = easier copy. Do not change report during a sked period. Do not mix report with callsigns. Do not use RST reports in initial skeds, unless you are very confident about signal strengths in both directions. ? Copied both callsigns + report Full 2.5 minutes then transmit only MRMR or OROR ? Copied both callsigns + report + R confirmation Full 2.5 minutes then transmit only R R R. ? Copied R R R If you have copied one R from the R R R... transmission, then the QSO is now complete. To confirm this to the other station, it is usual to transmit R R R, 73 TNX GL SK etc.
5.5 Incomplete sked QSOs - Coordinated skeds are of 30 minutes duration. If the QSO is incomplete at the end of the 30-minute sked period, you should generally abandon the sked - someone else will probably need the frequency. 'Private' skeds may continue longer, but should not be on frequencies used for coordinated skeds.

6. Random QSOs - Most QSOs on 432MHz and 1296MHz are 'random' - not by skeds. Usually there are no fixed time periods because both stations can hear when to change from RX to TX. The basic format for a random QSO is the same as for a sked, except that one station has either called CQ, or has signed out of a previous QSO on 'his' frequency. Example K1RQG has called CQ. DL4EBY is going to call him for a random QSO.
6.1 Calling a station - Frequency If you have set your RX clarifier (RIT) so that your echoes are at the same audio pitch as K1RQG's signal, then he will hear you on exactly the same frequency as his own echoes. You may not want to call exactly on that echo frequency, because it may be the frequency of a pile-up! Sending callsigns - Send both callsigns - remember that both stations must copy both callsigns for a valid QSO. However, it may be useful to give more repeats of your own callsign to help K1RQG to identify it, e.g: K1RQG DE DL4EBY DL4EBY... The optimum format and length of the call is a matter of operating skill and judgement.
6.2 Answering a call - If you copy both callsigns, Reply with both callsigns, with extra repeats of the calling station, e.g: DL4EBY DL4EBY DE K1RQG... The other station has almost certainly copied your callsign, but he must copy his own callsign from you. Then send a report. The rest of the QSO continues as described in the sked example above. If you have not copied either callsign for sure Transmit QRZ? QRZ? QRZ? DE... several times. DL4EBY should reply with both callsigns as above, for 1 minute or more. If K1RQG replies with QRZ? again, call him for even longer! Note to other stations: QRZ? is NOT an invitation to break in! If you have copied your own callsign Often you copy your own callsign easily, but have difficulty in identifying the unknown callsign. You have two choices:
a) Call QRZ? as above.
b) Send Y Y Y Y Y Y Y DE K1RQG... Y Y Y means "I need Your callsign only. I have already copied my own callsign." DL4EBY should reply with his own callsign only, for 1 minute or more. After a second Y Y Y, call for even longer! [YYY is very effective, but it needs more publicity! Zdenek has proposed to repeat each letter many times, e.g. "OOOOO KKKKK 11111 DDDDD FFFFF CCCCC". When this pattern is repeated, it could be difficult to understand where the callsign begins and ends. Please discuss!]

7. ARRL non-EME contest procedure: ARRL VHF/UHF contests use large grid squares (e.g. FN32) as multipliers, but do not require exchange of a signal report. On EME, the procedure is the same as described above, but send your grid square instead of the report. G G G means "I need your grid square for ARRL contest."

8. Polarization switching / rotation: The EME Directory lists stations with linear rotatable (rot.) and linear switchable (h/v) polarisation capability. If only one station can change polarization, he should optimize polarizations in both periods, and should transmit second in skeds. If both stations can change polarization, both stations should transmit horizontal and switch/rotate to receive. [No change above. Suggest we drop the experimental procedure for polarization ("If you copy P P P... change your TX polarization back to an earlier setting.") because there has been no interest.]

9. Breaking the rules! For a newcomer, it often seems that people do not use these procedures - but this is only partly true. Stations who have worked each other many times, and have strong signals, may decide to have a more 'normal' amateur radio QSO without using these special EME procedures. Even so, the basic QSO format is still there as a framework. If signals become difficult to read, good EME operators should move back toward the standard procedures, i.e., Reduce high speeds, send more clearly, Use M/O reports instead of RST, Do not change frequency or TX polarization, Change back to standard TX/RX periods synchronized to UTC.


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