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 unmistakeable 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:

    1. A scheduled contact, where two interested stations agree in advance on the mode (telegraphy or SSB), frequency, timing and period of the contact. This may be done by exchanging letters, or via the VHF net, which is active from 1100 to 1400 UT on each Sunday around 14.345 MHz, 28.345 MHz or 3.624 MHz, depending on the propagation conditions on the HF bands.

    2. 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 and 1 minute periods on SSB. 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, especially during major showers.

    1. All MS operators living in the same area should, as far as possible, agree to transmit simultaneously in order to avoid mutual interference.

    2. 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.

    3. 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

    1. 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 144.095 - 144.126 MHz and 144.395 - 144.426 MHz.

    2. Non-scheduled contacts

      The frequency used for CQ calls for non-scheduled contacts should be 144.100 MHz for telegraphy and 144.400 MHz for SSB. QSO's resulting from the CQ calls should take place in the 144.101 - 144.126 MHz frequency segment (telegraphy) or 144.401 - 144.426 MHz frequency segment (SSB), so as to avoid interference on the calling frequencies.

      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:

      1. Select the frequency to be used for a QSO by checking whether it is clear of traffic and QRM.

      2. 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.

      3. A = 1 kHzCall would be CQA CQA CQA
      4. E = 5 kHzCall would be CQE CQE CQE
      5. N = 14 kHzCall would be CQN CQN CQN
      6. Z = 26 kHzCall would be CQZ CQZ CQZ
      7. In all cases the letter used indicates a frequency higher than the CQ frequency.

      8. At the end of the transmitting period the receiver should be tuned to the frequency indicated by the letter used in the CQ call.

      9. 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.

      10. 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:

      1. Listen on 144.100 MHz for telegraphy or 144.400 MHz for SSB CQ's. (Note that when there is considerable activity during major showers stations calling CQ may QSY lower than 144.100 or 144.400 MHz in order to be on a clearer frequency).

      2. 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.

      3. 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.

      4. 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. Telegraphy speeds

    Speeds from 200 to 2000 letters/min. are now in use, but in non-scheduled MS work speeds between 400 - 700 letters/minute are recommended.

    In scheduled work the speed should always be agreed before the QSO, especially if one station does not have a multi-speed tape recorder. Some operators cannot reach the higher speeds now in use.

    Note that in some countries, including the UK, the licensing authorities require the callsigns to be sent at a lower speed at the start and finish of each transmission.

  7. QSO procedure for scheduled contacts and random operation

    1. Calling

      The contact starts with one station calling the other, e.g. "DL7QY SM3BIU DL7QY ....". In telegraphy the letters "de" are not used.

    2. Reporting system

      The report consists of two numbers:

      First number Burst duration Second number 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

    3. 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.

    4. Confirmation procedure

      1. 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 ...".

      2. 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.

    5. 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.

  8. 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 Miskloc-Tapolca (1978), and later slightly amended at the IARU Region 1 Conference in Noordwijkerhout (1987), Toremolinos (1990) and de Haan (1993).

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