OPERATING PROCEDURES FOR METEOR SCATTER QSO'S
1. Introduction
The goal of the procedures described is to enable contacts to be made by meteor scatter reflection
(MS) as quickly and easily as possible. As the reflections are of very short duration the normal QSO
procedure is not readily applicable, and special measures must be taken to ensure that a maximum of
correct and unmistakable information is received. The best meteor showers are mostly strong enough
to make some of these measures unnecessary, but to encourage use of all generally listed showers
there is no reason why the suggested procedures should not always be used.
2. Definitions
Two types of MS contacts, arranged in different ways, may be distinguished:
a. A scheduled contact, where two interested stations agree in advance on the mode (for example
on telegraphy, SSB or FSK441), frequency, timing and period of the contact.
b. A non_scheduled contact, where a station calls CQ or responds to a CQ call. Such contacts are
often called "random MS".
3. Timing
It is recommended that stations use 2.5 minute periods on telegraphy, 1 minute periods on SSB, and
30 seconds in FSK441. This practice gives quite satisfactory results. However, growing technical
standards make it possible to use much shorter periods and amateurs may wish to arrange 1 minute
schedules for telegraphy and shorter periods for SSB and FSK441 especially during major showers.
a. All MS operators living in the same area should, as far as possible, agree to transmit
simultaneously in order to avoid mutual interference.
b. If possible, northbound and westbound transmissions should be made in periods 1, 3, 5 etc.
counting from the full hour. Southbound and eastbound transmissions should be made in periods 2, 4,
6 etc.
c. When arranging schedules, one or two hours duration for the schedule may be used. Starting
times should be on the hour (e.g.0000, 0100, 0200 UT etc.)
4. Scheduled duration
Every uninterrupted scheduled period must be considered as a separate trial. This means that it is not
possible to break off and then continue the contact at a later time. The duration of scheduled periods
is usually one hour or, in some cases, two hours.
5. Choice of frequency
a. Scheduled contacts
Scheduled contacts may be arranged on any frequency, taking into consideration the mode/bandplan,
but should avoid using known popular frequencies and the random MS frequency segments near
144.100 MHz (telegraphy) and 144.195 – 144.205 MHz (SSB).
b. Non_scheduled contacts
The frequency used for CQ calls for non_scheduled contacts should be 144.100 MHz for telegraphy
and 144.195-144.205 MHz for SSB and 144.370 for FSK441.
QSO's resulting from the CQ calls should take place in the 144.101- 144.126 MHz frequency segment
(telegraphy).
Users of FSK441 should indicate the frequency they intend to carry out the QSO by adding the three
digits of the nominated frequency. For example CQ383 indicates that the station will listen on 144.383
MHz for a subsequent contact.
On telegraphy, the following procedure should be used by the caller to indicate during the CQ on
which exact frequency he will listen for a reply and carry out any subsequent QSO:
i) Select the frequency to be used for a QSO by checking whether it is clear of traffic and QRM.
ii) In the call, immediately following the letters "CQ", a letter is inserted to indicate the frequency
that will be used for reception when the CQ call finishes. This letter indicates the frequency offset
from the actual calling frequency used. For instance, CQE CQE CQE would indicate that the operator
would listen on the calling frequency + 5 kHz.
A = 1 kHz Call would be CQA CQA CQA
E = 5 kHz Call would be CQE CQE CQE
N = 14 kHz Call would be CQN CQN CQN
Z = 26 kHz Call would be CQZ CQZ CQZ
In all cases the letter used indicates a frequency higher than the CQ frequency.
iii) At the end of the transmitting period the receiver should be tuned to the frequency indicated by
the letter used in the CQ call.
iv) If a signal is heard on this frequency it may well be a reply from a station who has heard the
CQ call and replies on the frequency calculated from the letter used during this call.
v) When the caller receives a signal on the frequency indicated during the call and identifies the
reply as an answer on his CQ, the transmitter is QSY'ed to the same frequency and the whole QSO
procedure takes place there.
Example: DF7VXS wishes to try a random MS experiment on telegraphy, and wants to start with
calling CQ. He first checks his receiver in the range 144.101 - 144.126 MHz and finds a clear
frequency on 144.107 MHz. He decides to call CQ on 144.100 MHz, and he must now add a letter to
his CQ call to indicate on which frequency he intends to listen. In this example he has chosen a
frequency offset of 7 kHz, and therefore he will have to include the seventh letter of the alphabet, the
letter "G", in his CQ call. Note that the station receiving the CQ call will reply on a frequency exactly 7
kHz above the one on which the CQ call is heard.
If an operator instead of calling CQ wishes to listen for a CQ call the following procedure should be
used:
i) Listen on 144.100 MHz for telegraphy. (Note that when there is considerable activity during
major showers stations calling CQ may QSY lower than 144.100 MHz in order to be on a clearer
frequency).
ii) When a CQ call is received, note the letter which follows the letters "CQ" in the call. From this
letter calculate the frequency offset which the calling station will use for receiving replies.
iii) QSY the transmitter higher in frequency by the number of kHz's found, and transmit a reply
during the appropriate period. The format for the reply can be found in section 7.
iv) As the QSO will take place on this higher frequency, continue to transmit and to listen (during
the appropriate periods) on this frequency. It may be that the station calling CQ will not hear your first
reply, but may do so during one or more subsequent periods. Hence there is no need to return to the
calling frequency.
Example: You receive SM3BIU who is calling CQH CQH CQH. This tells you that, regardless of the
exact frequency SM3BIU is using for his CQ, he will be listening for a reply exactly 8 kHz higher, as H
is the eighth letter of the alphabet. Having established that the CQ was "CQH" you will call him 8 kHz
up.
N.B. The letter system should not be used for SSB contacts!
(De Haan, September 1993)
6. QSO procedure for scheduled contacts and random operation
a. Calling
The contact starts with one station calling the other, e.g. "DL7QY SM3BIU DL7QY ....". In telegraphy
the letters "de" are not used.
b. Reporting system
The report consists of two numbers:
First number Second number
(burst duration) (signal strength)
2 : up to 5 sec. 6 : up to S3
3 : 5 _ 20 sec. 7 : S4, S5
4 : 20 _ 120 sec. 8 : S6, S7
5 : longer than 120 sec. 9 : S8 and stronger
c. Reporting procedure
A report is sent when the operator has positive evidence of having received the correspondent's or his
own callsign or parts of them.
The report is given as follows: "UA1WW I1BEP 26 26 UA1WW I1BEP 26 26 ....". The report should
be sent between each set of callsigns, three times for telegraphy, twice for SSB, and must not be
changed during a contact even though signal strength might well justify it.
d. Confirmation procedure
i) As soon as either operator copies both callsigns and a report he may start sending a
confirmation. This means that all letters and figures have been correctly received.
Confirmation is given by inserting an R before the report: "SM7FJE G3SEK R26 R26 SM7FJE ...". A
station with an R at the end of the callsign could send "GW3ZTH I4BER RR27 RR27 ...".
ii) When either operator receives a confirmation message, such as "R27", and all required
information is complete he must confirm with a string of R's, inserting his own callsign after each
eighth R: "RRRRRRRR HG5AIR RRRR ....". When the other operator has received R's the contact is
complete and he may respond in the same manner, usually for three periods.
e. Requirements for a complete QSO
Both operators must have copied both callsigns, the report and a confirmation that the other operator
has done the same. This confirmation can either be an "R" preceding the report or a string of
"RRRR..."'s as explained in paragraph 7.d.ii.
7. Missing information (telegraphy only)
If a confirmation report is received at an early stage in the contact, the other operator has all the
information he needs. The following strings may then be used to ask for missing information:
BBB.... both callsigns missing
MMM....my callsign missing
YYY.... your callsign missing
SSS.... duration and signal strength missing
OOO.... all information complete
UUU.... faulty keying or unreadable
The other operator shall respond by sending only the required information. This approach must be
used with great caution to prevent confusion.
Note. These procedures were adopted at the IARU Region 1 Conference in Miskolc-Tapolca (1978),
later slightly amended at the IARU Region 1 Conference in Noordwijkerhout (1987), Torremolinos
(1990), de Haan (1993) and San Marino (2002)