This document describes the Standard Operating Procedures for HSMS (HSCW and FSK441) operation throughout the IARU Region 2, North and South America. SSB and slow CW procedures are also covered briefly, below.

If you operate only FSK441 MS and JT44/JT65 and and do not want this entire text, a shorter summary for only FSK441 and JT44/JT65 can be found at

In following these procedures, all stations using HSMS for meteor scatter communications within the Americas 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 MS to be confident that every operator knows what the others are doing. This revision reflects the ongoing growth and changes of HSMS operation in Region 2, especially with the addition of FSK441 MS.
Note - Meteor scatter procedures for Region 1 are not the same, and EME procedures (worldwide) differ from MS procedures, and also differ on the various bands. See the appropriate documents for more, and use the proper procedures for the region, mode, and band. As the old saying goes, "When in Rome, shoot Roman candles!"

TRANSATLANTIC TESTS - As these tests become more common, it should be publicly announced what set of procedures are being used.

The stated frequency is the USB dial reading.

The stated frequency is the signal's actual zero-beat frequency, or the frequency that would be displayed by a frequency counter during key-down.
Thus, when using audio-tone injection, the dial frequency is the desired zero-beat frequency minus the tone frequency.
For example: for a schedule on 144.110 - Transmitter VFO is set on 144.108 USB, 2000 Hz audio tone injected. Sked is thus made for "144.110" (or "144.110 ZB"). Receiving station will want approximately a 1500 Hz tone, so will put the receiver on 144.108.5 USB.
(This is using audio-injection J2A keying. Direct A1A make-break keying cannot be used in North America at the normal HSCW speeds).

On meteor scatter schedules using FSK441, the Western-most station transmits the first calling period. Since 30-second periods are used, this would be the first 30 seconds of each minute.
For HSCW schedules, the Western-most station transmits the first calling period (first minute) of each hour and half hour.
NOTE - This is for Western Hemisphere, Region 2, MS. In all other parts of the world the reverse sequencing is used.
("Western station transmits first" has been the procedure for North America since the 1950's, so it's difficult to try to change now).
DXpeditions normally run all schedules and CQs using the same sequence, usually the first period, regardless of direction (recommended).
Also, CQs by any station may be on either period, and commonly are on the first period (because on MS a reply may come from any direction).

The same as for any mode of operation or propagation - an exchange of both call signs, an exchange of some type of information or report, and an exchange of confirmation of reception of the report or information.
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 usually need at least two R's to be sure!), the QSO is officially complete. However, the other station will not know this. So it is customary to then send "73" to let the other station know that it's complete, even though the "73" is not required for a complete QSO.

Mobile, portable and DXpedition stations normally never send 73 unless they're shutting down, but instead return to calling CQ immediately after the exchange of R's.

IDENTIFYING: When the schedule progresses to the "Roger, Report" and later sections, calls are no longer being sent. To remain legal, the simplest method is this:
ON FSK441, activate the automatic ID in WSJT so that it will send your ID.WAV file at the proper time.
On HSCW, every ten minutes jump back to the first (calls-only) transmit buffer for about one second, then immediately return to the current transmit buffer.

Except when something special is required for a contest, an exchange of any additional information is valid for a QSO. The commonly-accepted (and expected) exchange for all HSMS operation is the burst duration-signal strength report ("2-number" report). This is now standard worldwide for HSMS operation.
1 - Ping with no info. (Not sent)
2 - ping, up to 5 sec in length 6 - up to S3 in strength
3 - 5-15 sec in length7 - S4 to S5
4 - 15-60 sec burst8 - S6 to S7
5 - over 60 sec burst9 - S8 and stronger
(In Australia where all MS operation is FSK441, there is a slight modification of this, with "06" meaning "20 ms, 0 to 10 dB," "17" meaning "40 to 80 ms, 11 to 16 dB," etc. See their HSMS Web sites for more).
Note that there cannot be any confusion between the first and second number as the ranges do not overlap; also note that the second number is not itself an "S-meter reading". (The duration report suggested here is slightly different from the European standard and also from some of the older North American charts).
This is now the preferred exchange for HSMS operation. But, if the other station uses a different reporting system, simply copy what he sends and send your report.
The typical ping will have a Burst Duration of 2, a Strength of 6. (This is a weak-signal mode).
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 send, even if you next get a "38-quality" ping. Changing the report could result in the loss of a contact.

Note on WSJT's FSK441 North American reporting: The #2 Standard Text Box defaults to "Firstcall report Secondcall report report" (e.g., K1JT 26 W8WN 2626). The reason for this format is to allow monitoring stations to tell which station they're hearing. Since the pair of calls is the longest string of text to exchange, lower-power stations may find it advantageous to change this to "Firstcall report Secondcall report" or even "Firstcall Secondcall report."
This change is definitely recommended for contests when the Grid Square is required for the report.

Other sometimes-used exchanges:
Burst length "S" report. Standard in North America since the 1950's for slow CW and later for SSB.
Grid square. Required for most contests. Sometimes used by portable or /MM stations; however, on FSK441, it is becomming common for the portable or /MM station to include their current grid in the CQ . The grid square normally should not be used on HSMS for the report except for contests.

An exchange of Rogers (R's) is necessary to complete a contact, regardless of the mode. But how many R's are required? It's much like the old question, "How many angels can dance on the head of a pin?"
Regardless of mode, only one (1) Roger is actually required. But are you sure you received it? Was it really an R? Many EME and MS operators have been greatly saddened to learn that the "definite R" they received was actually another letter, chopped up! This is why most operators don't trust conditions and their hearing to accept a single, isolated R, but prefer to have 2 or more.
So how many R's are required? As few or as many as you need to feel comfortable that you have it! If you rely on only a single R, many times you'll be correct. But all too often you'll later learn that the other station was not sending R's and the contact was not completed. (Those of us who have been on MS and EME for awhile have experienced this all too often - from both ends!)

On High-Speed CW MS operation, it is possible to request a missing piece of information.
Note - this does not work as well for FSK441, but could possibly be used.
(On FSK441, it's best to just ask for the needed information as these letters are likely to be interpreted as only gibberish).

BBB - Both call signs needed
MMM - My call sign needed
YYY - Your call sign needed
SSS - Report (or whatever report/information exchange used) needed (some have suggested GGG for needing the grid)
UUU - Ur keying is unreadable
(Use "U" when needed. Remember that the other station cannot monitor his keying).
These "requests for repeat" letters are used only when the other station mis-copies something and jumps ahead in the sequence. Thus, they are seldom needed (but very valuable at that time).
When these are used, nothing but the appropriate string of letters is sent. (E.g., "YYYYYYYYYY").
The other operator should respond by sending only the requested information. (E.g., "W8WN W8WN W8WN").
When the requesting operator has the needed data, he returns again to the proper exchange sequence.

For CQs, a speed of 6000 lpm has now become standard in North America, with most schedules run between 6000 and 10,000 lpm.

HSCW SCHEDULES - always determine what speed the other operator wishes to use. If you are very far off the other station's speed, not only is copy impossible, you can't even tell whether he's a lot faster or slower than your settings!
The most effective schedule speeds with current equipment and techniques are 6000-10,000 lpm. The signal-to-noise ratio becomes poorer above about 12,000 lpm; thus, higher speeds are not recommended for routine operating, although a number of stations are testing various techniques for use at these higher speeds.


Schedule frequencies are arranged between the two individual stations on any seemingly unused frequency.
On 144 MHz, North American HSMS operation is normally conducted between 144.100 and 144.200 to avoid interference with EME operation below 144.100, and with SSB operation near and above 144.200.
(Remember, in the US, frequencies below 50.1 and 144.1 are CW only).

At this time, most 50 MHz schedules are being made between 50.240 and 50.310.
Schedules should always be made at least 5 kHz away from the calling (CQ) frequencies.
(Speeds, frequency, exact procedures, etc., must always be confirmed between the two stations, especially if something different from the standard procedure is desired or one of the operators is new to this mode).

CALLING CQs - no offset:
On 2 meters - 144.140 dial for FSK441 and 144.100 zero-beat for HSCW.
Call, listen, and operate on the same frequency, unless there seem to be several stations operating there. If this is the case, the CQ-Letter or Uxx/Dxx method should be used.
On 50 MHz - 50.260 dial for FSK441 and 50.300 zero-beat for HSCW.
Either period may be used, since they could be answered from any direction (see sequencing).
HSMS CQs on other frequencies are almost certain to be unsuccessful unless they have been announced on the proper real-time Web site.
Note - except during contests or other periods of high activity, it is always necessary to announce that you are going to call a CQ.
For other VHF/UHF bands, no calling frequencies have been decided on. Due to the difficulty of operating MS on 220 and 432, all operation is currently by means of schedules.

FSK441 - If it is apparent that there are several operating, immediately following the letters "CQ", a specific letter and number are inserted to indicate the frequency that will be used for reception when the CQ sequence ends.
For example: "CQU5" means "I'm listening and will reply Up 5 kHz."
"CQD8" means "I'm listening and will reply Down 8 kHz".
The offset frequency is always relative to the CQ frequency. Thus, "CQU8" on 144.250 would mean that the contact will take place on 144.258 MHz. (144.250 is not a good frequency for an HSMS CQ, but is simply used as an example).
When using FSK441, instead of sending Up or Down, you could specify the actual frequency, such as "CQ 123" would mean "I am listening and will answer on 144.123 MHz."
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.

HSCW - If it is apparent that there are several operating, immediately following the letters "CQ", a specific 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 example, "CQE" would indicate that the CQing station would listen 5 kHz above his CQ frequency. 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:
CQC - Up 3 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 CQs, the letter again indicates the number of kHz higher where they are listening and to which they will QSY for QSO attempts.

CQ with GRID SQUARE - It is now common for /MM, /M, and portable stations (who may change locations) to include their Grid Square in the CQ. This enables the receiving stations to know the location of the portable/mobile station, and whether or not they need that particular grid square. Thus, W1LP/MM might call "CQ W1LP EL62". This is not recommended for fixed stations - it adds unnecessary information to the CQ, as the locations of most fixed stations are usually already known.

If it is only a straight CQ, you transmit and receive on the frequency that is being used for the CQ.
If it is a CQ-letter or a CQUxx or CQDxx, you change both your transmitter and receiver to the indicated frequency.
You then call and listen on this new frequency. When (if) the CQing station copies both calls, he will also QSY to this new frequency and the contact will take place there.
WARNING - Even during a major shower, pings may be few and far between. When you reply to a CQ, do not quit after only a few minutes. It may require 20 minutes, 30 minutes, or longer before the CQing station copies your call and you get a ping back from him. Plan to continue calling for a while.
When you call the CQing station, you use the standard 1x1 calls (e.g., W4HHK N1BUG W4HHK N1BUG, etc. - NO reports. [This is different in Europe]).
When the CQing station copies you (on the new frequency, if a CQ-letter or CQUx or CQDx has been used), he will respond with both calls and a report.
The calling station continues with the 1x1 calls until he copies the calls and report, then switches to the Roger-Report, and then on through the usual sequence.
(If the CQing station gets only partial calls, he should QSY and call "QRZ?" on the new frequency).

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

The Internet has made the setting up of schedules, checking results, real-time help, etc, very easy. Its use (and other, similar methods) are always encouraged for these purposes.
But what about confirming individual portions of a contact in real time, while the contact is in progress? (E.g., "OK, I have your calls and report, I'm sending R26s now", etc).
This depends upon the purpose of the attempted contact. For many contests, this is not allowed. And if contact by any other means is made while the attempted VHF contact is in progress and any information concerning the contact is exchanged, the contact must be restarted again from the beginning.
For claiming a record, or for a new state, etc, while not technically "illegal", it is strongly frowned on and discouraged. Most VHF operators do not communicate with the other station by the Internet (or similar means) from the time the contact has started until it has obviously been completed (i.e., one station has received "73").
Obvious exceptions to this would be if there's a major problem at either end (need to change frequency, rig problems, the other signal is not readable, etc), or incidental comments having nothing to do with the contact in progress.
For routine contacts, tests, experiments, etc. with a station you've worked many times, obviously there's nothing wrong with comments concerning the contact, for you won't even bother exchanging QSLs again. And the Internet is a great way to help fellows set up their rig, learn the proper procedures, and get things operating properly.
The bottom line is, what is the purpose of the VHF contact? If it's really to make this VHF Contact, it should be made on VHF with no outside help, once the schedule is set up and started. If it's completely routine, one contact of many with that station, for tests or help, etc, and it really doesn't matter whether or not the contact is completed, then it really doesn't matter what else you're doing at the same time.

These are the current HSMS Procedures for Region 2. If you wish to experiment with variations, that is up to you and the other station; this is the way the procedures grow and improve. 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, or by not knowing what to do!

exchange requirements and procedures are the same as HSMS procedures, with the following changes:
  1. The period is normally 15 seconds, with the Western station again calling first at the start of each minute.
  2. Random MS operation does not necessarily follow an exact sequence. Break-in is commonly used.
  3. Information exchange (report) is usually the burst-length "S" report (S1 through S5) on schedules, Grid Squares on random contacts. For random contacts, yet other exchanges are sometimes heard.
  4. Phonetics must be used for random operation; they should not be used for schedules.
  5. For CQs, the usual SSB calling frequencies are usually used during periods of low activity. However, during the peaks of major showers, they quickly become overcrowded. Frequencies every 5 kHz above and below the calling frequencies are then commonly used.
  6. On SSB, attempts are usually made to complete the entire QSO on a single long burst. Thus, break-in procedures should be used whenever possible.

Again, the procedures for CW are the same as for HSCW or SSB, with the following changes:
  1. The period may be 15, 30, or 60 seconds. Thus, this must be stated.
  2. The exchange (report) is normally the burst-length "S" report.
  3. Random CQs may follow the 15-second sequence, or they may be short calls with a break.

JT44 and JT65, other weak-signal modes of WSJT, are useful for distances too short for meteor scatter operation but where tropo scatter might be possible, and especially for EME operation. They should also be good for TE, IOS, and other modes of propagation where the signal is expected to be very weak but more or less steady.
For terrestrial JT44/JT65 operation (i.e., not EME), procedures, sequencing, etc., may be either the same as for MS or for EME! Therefore, the sequencing must be stated and agreed on prior to each schedule.
Frequencies used are in the same portion of the band as used for meteor scatter operation. There is no commonly-accepted frequency for CQs, though 144.163 has been proposed.

For JT44/JT65 EME operation, the procedures are generally the same as worldwide EME procedures for the band in question, except for the length of the transmit period (30 seconds for JT44, 60 seconds for JT65).
On 144 MHz, two sets of frequencies are currently in use - 144.105-144.135 and 144.145-144.170. EME JT44/JT65 CQs are most often simply announced on the JT44 EME Web page.
Japanese stations must operate above 144.4.
(Remember, in the US, frequencies below 50.1 and 144.1 are CW only).

This "Procedures" paper is primarily for meteor scatter operation. JT44/JT65, both EME and terrestrial, are too new for all of the proceudres to have been worked out. If you have questions, people on the "Ping Jockey" and "JT44" real-time web pages, as well as the "HSMS/JT44 Reflector," should be able to give you the latest information.

Region 1
Meteor Scatter procedures can be found at URL (Due to be revised soon).
This Region 2 document covers only the basic procedures. For more General HSCW information, go to or, and follow the links. Charts and many other papers are available to assist with both operating and technical information.
To download the latest version of WSJT, go to, or the mirror site at
To keep up with what is happening on meteor scatter, JT44 operartion, and general VHF news, check the Hot News Page regularly at

(Rev 2004/02, V. 23 - edited by W8WN) - hscw-sop.htm