This short guide outlines the
basic techniques to work MS. It is intended to give the complete beginner enough
information to attempt a few SSB contacts on the six metre band.
Basic Station Requirements
It is difficult to specify the
lowest power and smallest antenna that can be used for MS as during major
showers contacts can be made with 10W and indoor dipoles. However, using higher
ERP will increase your chances of success. Elevation is not necessary although
it could be useful for short distance contacts (less than 400km). The only other
requirement is an accurate digital watch as you will need to know the time to
within one second.
On 50MHz and during the bigger
showers it is sometimes possible to make contacts using ‘normal’ QSO
techniques. But as MS bursts are often quite short, special procedures have also
been developed to exchange the information needed for a complete contact as
quickly as possible and this will increase your chances of success.
The exchange consists of both
callsigns, a report and a confirmation that all has been received OK. As signals
will only be heard intermittently there is great danger of doubling with the
other station. To prevent this a strict sequence of one minute TX followed by
one minute RX is employed. The reporting system used consists of two numbers
unique to MS operating. The first number indicates the burst duration and the
second the burst strength. Once you have started to send a station a report it
is NEVER changed, even though the reflections may improve or deteriorate. The
numbers used are as follows:
First Number (Burst Duration)
2- bursts up to 5 sec
3- bursts 5 to 20 sec
4- bursts 20 to 120 sec
5- bursts exceeding 120 sec
Second Number (Burst Strength)
6- up to S3
7- up to S5
8- up to S7
9- S8 or stronger
Therefore if you hear short and
weak bursts you will probably send "26". Phrases such as "This is
G9ZZZ calling G5XYZ" have no place in MS operating procedures, only
essential information is sent.
Pings but no positive
Small part of either
callsign, partial callsign + report butcalls incomplete
Both calls + report 2
Both calls + report
Both calls + roger
report 2 times
Both calls + roger
report, Rogers Rogers
During skeds, stations will
call without the use of phonetics as both parties know who they are listening
for. During random contacts use of the phonetic alphabet is recommended. At
times when major showers are in progress it is recommended to "Break"
every 15 seconds in case a long burst is in progress.
The QSO starts with one station
calling the other eg "G9ZZZ G5XYZ G9ZZZ G5XYZ.
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 then given as follows "G9ZZZ
G5XYZ 26 26 G9ZZZ G5XYZ 26 26."
As soon as either operator
copies both the calls and the report, he can start sending a confirmation
"G9ZZZ G5XYZ Roger 26 Roger 26 G9ZZZ G5XYZ Roger 26 Roger 26..."
When either operator receives a
confirmation message (eg Roger 26) and all other information is complete he must
confirm with a string of Rogers usually for 2/3 periods. It is a good idea to
insert "73" now and then in order to stop yourself cracking up!
In order to maximise the chance
of success, skeds should be arranged at optimum times. The sporadic meteor rate
peaks at 0600 daily but during showers it is possible to be more specific;
computer programs and data sheets are available for this purpose.
There are two ways of arranging
MS skeds. The most convenient method is on the radio. Many six-metre operators
are also QRV on two metres and can often be heard setting up skeds on the vhf
net (14.345 +/-).
The six metre liaison frequency
(28.885) depending on conditions can also be used to set up skeds. Packet radio
and e-mail are also good ways of directing sked requests to Europe.
Alternatively one can write to a station heard arranging skeds if you do not
have the facility to transmit.
When arranging an MS sked, a
certain minimum amount of data needs to be exchanged:
B. Time (start, finish)
C. Length of periods
E. Which station transmits first
F. mode (CW/SSB)
If high-speed CW is to be used then the maximum
speed you can accept must also be specified. In the bigger showers hand-speed CW
can be used quite successfully on 50MHz.
UKSMG Six News