This document describes a set of guidelines for standardized HSCW operation throughout the IARU Region 2 (North and South America). In following these procedures, all stations using HSCW for meteor scatter communications within the Americans will be operating in an expected and regular manner, ensuring highest communications efficiency. These procedures are not a set of "rules", but rather an attempt to allow all those operating HSCW to be confident that each operator knows what the other is doing. These have been taken both from standard American slow-speed CW MS operation and from European HSCW procedures. (However, in a number of instances it has been found that neither of those guidelines adequately covered the type of HSCW operation being done in North America).
All procedures have been tested, discussed, and modified as necessary after months of actual on-air use. But at this time you will still find two different methods of stating the frequency, two different types of signal reports, and little agreement about what is the "best" speed to use. No doubt all of these procedures will continue to "evolve" over the next few years, and some may change completely. For now, during routine schedules and CQ's, this is what seems to work best and what will cause the least confusion by all stations. It is suggested that you download and save this as a TEXT file, edit out the examples to shorten it, then print out a copy of the basic information. This can be very helpful at 4 a.m.!


- The stated frequency is the signal's actual zero-beat frequency.
Thus, when using audio-tone injection, the zero-beat frequency is the USB dial readout plus the frequency of the injected tone.

For example: for a sked on 144.157 - Transmitter VFO set on 144.155 USB, 2000 Hz audio tone injected. Sked made for " 144.157 Zero Beat" (or "144.157 ZB"). Receiving station will want approximately a 2000 Hz tone, so will put the receiver on 144.155 USB.
This is the method in use in Europe and preferred in North America as the most understandable method, especially as higher speeds (and thus higher injected tones) are used.

- The frequency of the schedule or CQ is given as the dial reading plus the injected tone frequency, which
must also be stated.

For example: the above schedule would be given as " 144.155 +2000 Hz".

For either method, you must know the frequency of your injected tone. (2000 Hz is the most commonly used tone frequency in North America, for a number of technical reasons. But if you are using the highest speeds, 2400 or 2500 Hz is recommended. See the Semi-Technical FAQ for more).

If you do not have a strong preference, the "zero beat" method is recommended.

REGARDLESS of which method you prefer, the method MUST be stated each time.

(Yes, this is confusing! But this is the way things are at present. All attempts to "simplify" this have failed! Therefore, understand both methods. Then each time state which method you are using. That's the best that can be done at this time. It works fine).


For CQ's, 144.100 (on 2 meters), using the above-stated setting procedure. Call, listen, and operate on the same frequency. (Because of the two different methods of stating the frequency, this actually becomes 144.100 +/- 2 kHz).

CQ's use a one-minute sequence. Either period may be used, since they could be answered from any direction. (As more stations become active, it may become necessary that all stations in certain areas call during a specific sequence to cut down on QRM).

For other VHF/UHF bands, the usual CW calling frequency is recommended.

If it is apparent that there are several operating, immediately following the letters "CQ", a letter is inserted to indicate the frequency that will be used for reception, when the CQ sequence ends. This letter indicates the frequency offset from the actual CQ calling frequency used. For instance, CQE would indicate that the CQing station would listen on his CQ frequency + 5 kHz. In all cases the letter used indicates a frequency higher than the CQ frequency. When the CQing station hears a call on the offset frequency ( not on the CQ frequency, for he is not listening there), he/she immediately then also moves to the offset frequency, and the QSO takes place there with BOTH stations now transmitting and receiving on the new designated frequency.

For example: CQA - Up 1 kHz

CQE - Up 5 kHz

CQZ - Up 26 kHz

CQAA - Up 27 kHz. Etc.

Note that the letter indicates the number of kHz higher than the CQ frequency. It does not indicate any specific frequency. Thus, if a Dxpedition is using some other frequency for CQ's, the letter again indicates the number of kHz higher that they are listening and to which they will QSY for QSO attempts.


Schedule frequencies are arranged between the two individual stations on any seemingly unused frequency. Attempts should be made, of course, to avoid interference with EME operation, 144.008-144.097 (and some 144.105-144.150), during times near perigee; and with SSB operation near and above 144.200. (Speeds, frequency setting method, exact procedures, etc., should always be confirmed between the two stations).


The same as for anything else. An exchange of both call signs, an exchange of some type of information or report, and an exchange of confirmation of the same.

When a station copies both calls, he sends calls and report.

If he gets both calls and a report, he sends his report & Roger.

If he gets report and Roger, he sends Rogers.

When both get a pair of Rogers (you must have at least two to be sure!), the QSO is officially complete. However, the other station may not know this. So it is customary to then send "73" to let the other station know that he can QRT.

A typical exchange:

W4HHK sends: N1BUG W4HHK N1BUG W4HHK etc. for one minute.

N1BUG sends: W4HHK N1BUG W4HHK N1BUG etc. for one minute.

W4HHK copies both calls on short, weak ping(s), sends: N1BUG 26 W4HHK 2626 N1BUG 26 W4HHK 2626 etc. (Note that everything repeats very rapidly, with no long runs of any one piece of information. HSCW uses fractional second pings. Repetition of the same information defeats its advantages).

N1BUG copies both calls and the report on a long, strong ping, sends: R37 R37 R37 etc. (No calls).

W4HHK copies R and report, sends: RRRRRR. (Obviously, no calls are being sent now!)

N1BUG copies R's. QSO is complete. Tells W4HHK that he has everything by sending: 73 73 73 73.

W4HHK copies the 73s, QRTs, completes his log sheet. (He may also send: 73).

Note that information previously received by the other station is not repeated as the sequence progresses.

(There can be a slight variation in the exact way this is done, depending upon what is received on the first pings. If a station first receives both the calls and the report before receiving only the calls, he would then skip directly to the Roger and report, etc., as there is no reason to waste time sending what has already been received . HSCW is meant to be very efficient).


Except when something special is required for a contest, an exchange of any information is valid for a QSO. The commonly-accepted (and expected) exchanges for MS operation are:

1 - Burst duration-signal strength report . Standard in Europe, now common everywhere for HSCW.

2 - Burst length "S" report . Standard in North America since the 1950's for slow CW & SSB.

3 - Grid square. Required for some contests. Otherwise not used.


              1  - ping,   no info (not sent)           
              2  - ping, up to 5 sec's        6   - up to S3
              3  -  5 - 15 sec's              7   - S4 to S5
              4  - 15 - 60 sec's              8   - S6 to S7
              5  - over 60 sec's              9   - S8 and stronger

To use the old "S " system - it is simply " S" plus the appropriate number from the first column. For the usual information-containing HSCW underdense ping it would be "S2".

To use the duration/strength report - for the same ping, with a weak signal, it would be "26". NOTE that there cannot be any confusion between the first and second number; also note that the second number is not itself an exact S-meter reading. (The duration report suggested here is just slightly different from the European standard and also from some of the older North American charts). This is the preferred exchange for HSCW operation. But, then - do you have to already know everything that's going to be sent? If the other station wishes to use a different reporting system, just copy what he sends!

Once you have started sending a report, it is NOT changed during that schedule, even though you suddenly get a much better burst. E.g., if you start sending "26", this is the report you would continue to transmit, unless it gets so good that you can start a rag-chew.


On high-speed CW MS operation, it is possible to request a missing piece of information.

BBB - Both callsigns needed

MMM - My callsign needed

YYY - Your callsign needed

SSS - "S" report (or whatever report/information exchange used) needed

UUU - Ur keying is unreadable

(Use this when needed. Remember that the other station cannot monitor his keying).


When used, nothing but the appropriate string of letters is sent.

The other operator should respond by sending only the requested information.

When the requesting operator has the needed data, he returns again to the proper exchange sequence.

This has proved to be very effective when both operators are aware of this and use it if they observe that the other station has mis-copied something and is sending the wrong data, or when the other operator may be accidentally sending from the incorrect transmit buffer (which we all have done!)


For CQ's, a speed of 1000-2000 lpm is recommended. 2000 lpm is the most common speed now. (It is expected that 4000 lpm will become common for CQ's in the near future).

If you intend to run slower than about 2000 lpm or faster than about 5000 lpm on a schedule, it is necessary that this be confirmed with the other station. Their equipment may not be set up to handle the slowest or fastest speeds. (It is very important to know the approximate speed to be used. If you try to play back a ping either much too fast or much too slow, you not only will be unable to copy it, you may not even realize that you are hearing a signal!)

For schedules , always determine what speed the other operator wishes to use.

The most effective schedule speeds seem to be 4000-6000 lpm. But this varies with the equipment in use, the skill of the operators, the path, etc. (At the higher speeds, increase your injected tone frequency. See the Semi-Technical FAQ for more on this).


On schedules, the Western- most station transmits the first calling period of each hour and half hour.

(Be especially careful when starting a schedule on the 15- or 45-minute period, as the "other" station actually calls first in order to be in the correct sequence).

This is for the Western Hemisphere. In other parts of the world the reverse sequencing is normally used.

If directions are nearly north-south, then the Southern station should transmit the first calling period of each hour and half hour.

NOTE that it is VERY dangerous to say "odd" or "even" minute or period. While it may seem obvious to you, if you say, for example, "odd minute", this can mean EITHER the first or the second minute, depending entirely on the other operator's frame of reference! Don't miss a QSO. Simply state everything in the manner that will cause the least confusion.
The Western-most station normally calls the first transmit period of the hour and half hour.

For CQ's , either period may be used. Also see above under CQ's.

For both schedules and CQ's, a period of one minute has become standard for HSCW operation.


Schedules are always made in Universal Time . However, for evening schedules, the local time/day may also be needed to be sure that the date is understood properly.

These are the current HSCW Procedures for Region 2. If you wish to experiment with variations, that is up to you and the other station. But by using these for routine operating, you are less likely to disappoint the other station by seemingly failing to show up for the schedule!

Region 1 Meteor Scatter procedures can be found at:
Region1 Procedures

For more North American HSCW information, go to:
one of the other HSCW Home Pages and
follow the links .


(Rev 02/07/98, V. 7)