Procedure by G3SEK

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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.