Amateur Radio Operating Practices
The following procedures represent good operating practices. Adherence to these practices will result in more efficient communications, will result in avoiding some communications problems, will make your communications demonstrate both experience and professionalism, and will result in your communications being accepted in the Amateur Radio community as a whole.
Amateur Radio is a self policing entity. In the past, many of these standards were enforced by Amateur Radio mentors (called Elmer's) and the Amateur Radio community. There has been an diminishing of quality of operating practices as many new Amateur Radio operators, coming from other radio services, bring radio practices from other services to the Amateur Radio service. But there is a reason why the original practices were put into place. Amateur Radio is first and foremost a public service. Amateur Radio is used, in its primary role, to provide public service communications, including traffic passing (radio-grams), public service event communications and emergency communications. These practices were put into place in order to facilitate the efficiency of communications in Amateur Radio's primary role. The habits that Amateur Radio operators develop in their day to day operation, which is secondary to Amateur Radio's primary public service roll, carry over directly to station operating practices when operating in the public service roll. That is why it is imperative that day to day Amateur Radio operating practices strive to adhere to good operating practices and the Amateur Radio community not adopt practices from other radio services that result in inefficient communications.
If an Amateur Radio operator offers a correction in response to observing a poor operating practice, this is not a personal attack. It is guidance that is being provided for the greater good of the Amateur Radio service and will have a direct application to operating in Amateur Radio's primary roll of public service communications.
Since the advent of Volunteer Examiner (VE) testing, the primary focus for study for the Amateur Radio license is toward passing the Amateur Radio examination. Little focus is applied to providing training on how to operate once the Amateur Radio license is obtained. With common familiarity of a push-to-talk (PTT) button, often the new operator is left to determine operating practices with little guidance, and, sometimes, the mistaken roll model of television depiction of radio operation. To leave the new Amateur Radio operator to his own devices in determining operating procedures is one of the largest failings of the Amateur Radio community. Unfortunately, this failure exhibits the worse case results in public service and emergency communications, resulting in misunderstood messages and excessive use of bandwidth (which results in delaying other communications).
Publication of these operating practices has this very goal, that is to provide the Amateur Radio operator with guidance so that their operating practices result in efficient communications, avoid unintentional interference and result in a more enjoyable experience for all involved.
The goal of every Amateur Radio operator should be to have basic operating habits that have direct application toward public service and emergency communications. The underlying foundations to achieve this goal includes:
Clarity of communication.
Proper basic radio operating techniques, based on an understanding of half-duplex operation.
Use of bandwidth (i.e. brevity).
Note that this does not mean a rigid adherence when conducting non-critical casual communications. It simply means that the foundation should be in place so that your station can be effectively integrated into a larger network of stations in support of public service and emergency communications.
Half-Duplex v.s. Full-Duplex
Half duplex simply means that you cannot hear the station or stations that you are communicating with while your station is transmitting. Nearly all Amateur Radio equipment supports only half-duplex communication. It is therefore imperative that an Amateur Radio operator develop the necessary skills to determine when the other station has completed transmission in order to avoid transmitting at the same time as another transmitter.
Half-duplex operation is contrary to our normal everyday communication where we are speaking with someone face to face. This communication is full-duplex, where we have the ability to interrupt or interject ourselves into the conversation. In such interactions, there may be no loss of data as the interruption can be detected and simultaneous speech can be avoided. While using half-duplex radio equipment, we are unable to detect an interruption to our own transmissions and, therefore, cannot stop transmission to allow interjection into the conversation.
The use of half-duplex operation is inherent when the radio station uses a transceiver, where the receiver and transmitter are integrated into a single unit and have mutually exclusive access to the antenna and audio components. The receiver is muted and has no access to the antenna when transmitting, thereby preventing the receiver from being overloaded by the transmitter signal and preventing a feedback loop between the receiver speaker and the transmitter microphone. The use of full-duplex communication processes when using a half-duplex radio is absolutely catastrophic to communications. Any interruption or interjection will not be heard by the station that is already transmitting, and usually will result in interference that prevents other stations from hearing one or both stations that are transmitting simultaneously.
Full-duplex operation can only be used when the receiver and transmitter are independent and only if the transmitter will not cause interference to the receiver (e.g. feedback from the receiver speaker to the transmitter microphone or desensitization of the receiver by the transmitter overloading the receiver).
A repeater is a full-duplex station, which requires specialized equipment, while a transceiver is always a half-duplex station. If full-duplex operation is applied to half-duplex station equipment, transmissions will need to be repeated and this will delay other communications. This could have extremely negative consequences to safety, life or property in an emergency communications or public service environment.
Never apply full-duplex operating procedures to half-duplex station equipment. Avoiding full-duplex operation involves simple procedures that either involve a hand-shake (i.e. transmission is handed from one station to the other using a call sign protocol) or by acquiring the skill to determine when a transmission has ceased (see Repeater Operation below).
Applying full-duplex operating procedures to half-duplex station equipment is considered to be poor operating procedure.
Calling Sequence Definitions
1 by 1 Calling Sequence
In a 1 by 1 calling sequence, the call sign of the station being called is pronounced or sent once, followed by the call sign of the calling station being pronounced or sent once. For example:
|1 BY 1 Calling Sequence|
|Morse||W7QRM DE K7QRN K|
3 by 1 Calling Sequence
In a 3 by 1 calling sequence, the call sign of the station being called is pronounced or sent three times, followed by the call sign of the calling station being pronounced or sent once. For example:
|3 BY 1 Calling Sequence|
|Morse||W7QRM W7QRM W7QRM DE K7QRN K|
|Phone||W7QRM W7QRM W7QRM K7QRN|
3 by 3 Calling Sequence
In a 3 by 3 calling sequence, the call sign of the station being called is pronounced or three times, followed by the call sign of the calling station being pronounced or sent three times. For example:
|3 BY 3 Calling Sequence|
|Morse||W7QRM W7QRM W7QRM DE K7QRN K7QRN K7QRN K|
|Phone||W7QRM W7QRM W7QRM K7QRN K7QRN K7QRN|
When making a general call, or establishing initial communications with another station, morse calling procedures uses a 3 by 3 calling sequence. Morse operation often involves the use of narrow band filters that impose a critical tuning requirement at the receive end of the conversation (QSO). The use of the 3 by 3 calling sequence enables the receiving station to tune the receiver properly to copy the morse transmission.
Once communication has been established, morse reverts to a 1 by 1 calling sequence.
Digital modes tend to follow the morse procedures but this is not always the rule. Some digital modes implement forward error correction and will copy text with great accuracy, reducing the need for repeated transmission of call signs. Digital modes that do not employ forward error correction may not copy the text perfectly and repeating the call sign on a first call or general call is advisable.
Digital mode operating involves using a software application. Usually, the software application provides user programable macro buttons that are used for general calling and for answering a general call. The macro buttons are mode insensitive. That is to say that the macro buttons do not know of you are operating in a mode that applies forward error correction. As such, the macro buttons are usually programmed for the worse case scenario of operating in a mode that does not support forward error correction (i.e. a 3 by 3 calling sequence).
Software applications that are dedicated to a specific operating mode, such as JT65-HF, which implements forward error correction, offer non-programmable macro buttons that are used to sequence through the stages of a conversation (QSO) and are optimized for the target digital operating mode. In this case, the calling mode is opaque to the operator.
Phone HF or Non-Channelized Calling
Phone HF or non-channelized operation requires tuning in the station being received using the Variable Frequency Oscillator (VFO). Because of this tuning requirement, phone HF or non-channelized operating procedures use a 3 by 3 calling procedure to establish communications. Once communications is established, phone HF or non-channelized operation reverts to a 1 by 1 calling procedure.
Phone FM or Channelized Calling
Phone FM or channelized operation does not require a sensitive tuning procedure to be completed. The receiving station is either on frequency or not. As such, the 3 by 3 calling procedure that is prevalent on phone HF and non-channelized operation is abandoned in favor of a 1 X 1 calling procedure on phone FM on channelized operation.
It is considered to be poor operating practice to use a 3 by 3 calling procedure on FM phone or channelized phone operation.
Please let the repeater squelch tail drop before beginning a transmission. This ensures that time is made available for emergency traffic to break in.
For those unfamiliar with the term squelch tail, this is the short burst of random noise that occurs in your radio that is due to a delay in detecting that the receiver is no longer hearing a signal and your receiver muting the audio. This same delay occurs in the repeater receiver, resulting in two short bursts of noise being heard when a station stops transmitting. The second burst of noise will occur delayed from the first burst of noise by the duration of the repeater squelch tail timer (nominally set to 1.5 seconds). If there is any doubt, your radio may include an S-Meter or an LED indication of signal strength, and these devices can be observed to determine when the repeater transmitter has been dropped when the S-Meter returns to zero or the LED turns off.
If you find yourself transmitting on top of another station, then you are probably having difficulty interpreting the squelch tail sound, and may even be queueing off of other noise that sounds similar to squelch noise. Mobile flutter and signal fading can closely mimic squelch tail noise but have subtle characteristics that allow for differentiation from squelch tail noise, the most obvious being that there is no consistent delay, associated with the squelch tail timer (nominally 1.5 seconds), between the noise bursts.
The following is an '.mp3' recording of the 147.020 MHz repeater squelch tail. The first noise burst in the recording demonstrates the squelch decay at the repeater receiver while the second noise burst, which occurs 1.5 seconds after the first noise burst, demonstrates the squelch decay at the local receiver after the repeater transmitter stops transmitting. This second noise burst represents the squelch tail. Amateur Radio operators often refer to this as the Ker-Chunk with the Ker representing the first noise burst and Chunk representing the second noise burst.
Do not use voice queues, such as hearing an answer to a question in the speech of another station, to determine when to transmit. Always wait for the squelch tail to drop the repeater transmitter, as indicated by the second noise burst, before transmitting.
Repeater QSO Operating Practices
Conversing stations should always let the squelch tail drop. This is done to ensure that transmission is not started by misinterpreting mobile flutter as the end of a transmission. It is also done to allow a breaking station to break in to the conversation during the squelch tail period.
Stations wishing to break in should listen for the first squelch gate decay, indicating that a transmitting station has ceased transmission. The station breaking in should start the break-in transmission before the repeater squelch tail drops. This procedure ensures that the breaking in station will be heard during the squelch tail and avoids doubling when the conversing station resumes transmission by enabling the break-in station to avoid simultaneous transmission with the conversing station.
Use of CQ
Calling CQ on a repeater is not normal procedure. Just announce your call sign. It is not unusual to hear someone informally ask for a radio check or if anyone is around. If you do call CQ, use a one by one calling procedure. A three by three calling procedure is not necessary on FM or repeater operation.
Use Of Language
For the most part, amateur radio operators use plain english to converse. This, in part, is due to amateur radio's role in emergency communications, where clarity and brevity are vital in order to reduce bandwidth and clearly communicate.
The operating habits and language that we use day to day will carry over to emergency communications. It is vital that good operating habits be formed so that emergency communications is not encumbered by the need to repeat a transmission based on non-standard use of the english language. Somebody's life may depend on it.
The general rule is to speak exactly as you would on a telephone, avoiding slang and obscure terms, speaking in a clear and concise manner. Station identification must occur every ten minutes when transmissions have been made. Music, swear words and broadcasting are not allowed. Other than that, you are free to exercise you first amendment right.
It should be noted that Federal Emergency Management Agency (FEMA) training, which defines inter-agency communication and includes Amateur Radio, defines the use of Plain Language in order to facilitate efficient communications.
The obfuscation of the english language, using non-common and unclear terms, is discouraged on amateur radio. Amateur Radio has a close relationship with emergency communications and introducing terms that are not immediately understood will lead to confusion and excessive use of bandwidth (time transmitting) due to the need to repeat communications in a clear manner.
For this reason, the use of slang on Amateur Radio is discouraged.
For this reason, the use of Citizens Band lingo on Amateur Radio is discouraged.
The use of Citizens Band radio lingo, such as Handle, That's a 10-4, and the like is considered to be poor operating practice.
10-Codes are not standardized. The definition of 10-codes varies among various radio services. Further, the definition of 10-codes varies among radio networks within a given radio service. As such, there is no standardized meanings for 10-Codes. As such, the use of 10-codes, or fragments of a 10-code is discouraged. Should the use of 10-codes be carried over to emergency communication, they would only generate confusion and would result in a consumption of unnecessary bandwidth in repeating and clarifying communication.
The use of 10-codes on Amateur Radio is considered to be poor operating practice.
Phonetics are used to clarify language when accurate duplication of a message is required. Amateur Radio uses the same phonetic alphabet as defined in the NATO Phonetic Alphabet, the International Radio-telephony Spelling Alphabet and the ICAO Phonetic Alphabet:
|ICAO Phonetic Alphabet|
|C||-•-•||Charlie||CHAR-LEE or SHAR-LEE|
|U||••-||Uniform||YOU-NEE-FROM or OO-NEE-FORM|
It is not unusual to hear other phonetic alphabets being used on Amateur Radio, including phonetic alphabets from public safety radio services or ad hoc phonetics (sometimes constructed for use with DX contacts). Ad hoc phonetics that are used for DX operating often use the name of a Country. This is not necessarily considered bad operating practice as the point is to communicate accurately, and use of phonetics that are either familiar or that use consonants that are easier to pull out in an environment with lots of noise or interference (such as occurs in a DX pile-up) may fulfill the stated goal.
Amateur Radio cannot interact with other radio services directly (i.e. over-the-air). Amateur Radio communications is always restricted to communications within the Amateur Radio service itself. For this reason, standardization is both possible and advisable. The use of phonetics during public service or emergency communications should adhere to the ICAO Phonetic Alphabet. Using other phonetic alphabets may result in habitual behavior that may make it extremely difficult to adhere to the ICAO Phonetic Alphabet when conducting public service or emergency communications.
Pro-words or Pro-signs
Pro-words are procedural terms and convey specific meanings:
|Pro-words or Pro-signs|
|Clear||End of contact.|
|Over||Used to let a specific station know to respond.|
|Go Ahead||Used to indicate that a station may respond.|
|Out||Leaving the air, will not be listening.|
|Stand by||A temporary interruption of the contact.|
Q-Signals or Q-Codes
Q-Signals or Q-Codes have their root in CW or morse operation, where bandwidth savings and uniformity of expression can be realized by applying a three character phrase to ask a question or describe a term that is commonly used in Amateur Radio. These same bandwidth savings and uniformity of expression carry over to phone operation.
Q-Signals can be used to pose a question, to respond to a question or make a statement:
|QRA||What is the name of your station?||The name of my station is ____.|
|QRG||Will you tell me the exact frequency (or that of ____)?||Your exact frequency (or that of ____) is _____ KHz.|
|QRH||Does my frequency vary?||Your frequency varies.|
|QRI||How is the tone of my transmission?||The tone of your transmission is ____.
|QRJ||Are you receiving me badly?||I cannot receive you. Your signals are weak.|
|QRK||What is the intelligibility of my signals (or those of ____)?||The intelligibility of your signals (or those of ____) is ____.
|QRL||Are you busy?||I am busy (or I am busy with ____). Please do not interfere.|
|QRM||Is my transmission being interfered with?||Your transmission is being interfered with ____.
|QRN||Are you troubled by static?||I am troubled by static ____.
|QRO||Shall I increase power?||Increase Power.|
|QRP||Shall I decrease power?||Decrease power or
I am operating with low power.
|QRQ||Shall I send faster?||Send faster (____ WPM).|
|QRS||Shall I send more slowly?||Send more slowly (____ WPM).|
|QRT||Shall I stop sending?||Stop sending.|
|QRU||Have you anything for me?||I have nothing for you.|
|QRV||Are you ready?||I am ready.|
|QRW||Shall I inform ____ that you are calling on ____ KHz?||Inform ____ that I am calling on ____ KHz.|
|QRX||When wil you call me again?||I wil call you again at ____ hours (on ____ KHz).|
|QRY||What is my turn?||Your turn is numbered ____.|
|QRZ||Who is calling me?||Your are being called by ____ (on ____ KHz).|
|QSA||What is the strength of my signals (or those of ____)?||The strength of your signals (or those of ____) are ____.
1. Scarcely perceptible
3. Fairly good
5. Very good
|QSB||Are my signals fading?||Your signals are fading.|
|QSD||Is my keying defective?||Your keying is defective.|
|QSG||Shall I send ____ messages at a time?||Send ____ messages at a time.|
|QSK||Can you hear me between your signals and if so, can I break in on your transmission?||I can hear you between my signals; break in on my transmission.|
|QSL||Can you acknowledge receipt?||I am acknowledging receipt.|
|QSM||Shall I repeat the last message which I sent you, or some previous message?||Repeat the last message you sent me [or message(s) number(s) ____].|
|QSN||Did you hear me (or ____) on ____ KHz?||I heard you (or ____) on ____ KHz.|
|QSO||Can you communicate with ____ direct or by relay?||I can communicate with ____ direct or by relay.|
|QSP||Will you relay to ____?||I will relay to ____.|
|QST||General call preceding a message addressed all stations.|
|QSU||Shall I send or reply on this frequency (or on ____ KHz)?||Send or reply on this frequency (or ____ KHz).|
|QSV||Shall I send a series of Vs on this frequency (or ____ KHz)?||Send a series of Vs on this frequency (or ____ KHz).|
|QSW||Will you send on this frequency (or ____ KHz)?||I will send on this frequency (or ____ KHz).|
|QSX||Will you listen to ____ on ____ KHz?||I am listening to _____ on ____ KHz.|
|QSY||Shall I change to another frequency?||Change frequency to ____ KHz.|
|QSZ||Shall I send each word or group more than once?||Send each word or group twice (or ____ times).|
|QTA||Shall I cancel message number ____?||Cancel message number ____.|
|QTB||Do you agree with my counting of words?||I do not agree with your counting of words. I will repeat the first letter or digit of each word or group.|
|QTC||How many messages have you to send?||I have ____ messages for you (or for ____).|
|QTH||What is your location?||My location is ____.|
|QTR||What is the correct time?||The correct time is ____.|
|QTV||Shall I stand guard for you?||Stand guard for me.|
|QTX||Will you keep your station open for further communications with me?||Keep your station open for me.|
|QUA||Have you news of ____?||I have news of ____.|
The use of Q-Signals during NET operations, including public service event communications and emergency communication, should be avoided.
Digital Mode Operating Tips
Adhere to published band-plans with respect to frequency utilization as applied to the specific digital mode that you are planning to use. The following table depicts a list of frequencies as applied to some of the more common digital operating modes:
|Digital Mode Band Plan|
|Olivia||Olivia 16/500||3522.00||3522.75||750||E. Asia||http://hflink.com/olivia/|
|Olivia||Olivia 32/1000||3522.00||3523.00||1000||E. Asia||http://hflink.com/olivia/|
Do not tune up on the primary operating frequency. You'll only be causing QRM. Move off a few KHz to tune up.
Honor DX Calling. If a station is calling CQ DX, they are indicating that they wish to contact stations of another country. If you are not a DX station, do not respond to a CQ DX call. Doing so will likely cover up a weaker DX station and result in your station causing interference to the station that is attempting to work DX. If the station is not including DX in a CQ general call then they will accept a call from any location.
If you hear a strong station calling CQ DX, don't select a frequency immediately adjacent to their transmission. Implied in their calling CQ DX is that they will be working weak stations. Your strong transmissions will cause the receiver automatic gain control (AGC) of the station that is calling CQ DX to attenuate the weak signals that they are attempting to work. Be courteous by moving off frequency so that the station working DX, in concert with a reduction in receiver bandpass, will have an unimpaired ability to copy the weak DX stations. See Avoid having the AGC destroy your QSO below.
Note that this practice should apply to all operating modes and not just digital operating modes.
Avoid Microphone Modulation. Many radios do not disconnect the microphone when making a digital transmission. This can result in illegal voice modulation occurring within band segments that do not allow voice transmission. If you're not sure if your microphone is hot, disconnect it when making digital transmissions. If you have a monitor receiver, check to see if your microphone is hot when making digital transmissions. DO NOT ASSUME THAT THE MICROPHONE IS MUTED DURING DIGITAL TRANSMISSION.
Restrict use of RSID transmissions. Limit the use of RSID to only those transmissions where you call CQ. Once your in QSO, RSID is completely pointless as the station you are working has quite obviously determined which digital mode you are using.
Do not transmit RSID on PSK31. Transmission of RSID on a PSK31 frequency is both unnecessary and redundant. PSK31 is easily identifiable on a waterfall display. Further, because PSK31 is the most popular and commonly used digital operating mode, and has commonly known frequencies used for PSK31 operation, using a mode other than PSK31 on those frequencies would be the exception. The transmission of an RSID on a PSK31 frequency is a poor use of bandwidth.
If a station is calling another station, do not call them until they have finished working the station they are calling or have clearly ceased the attempt. To do can cause them to not copy the station they are calling. This can be particularly frustrating on slower modes, like JT65-HF, where transmissions start at 1 second after the minute and run until 48 seconds after the minute. A missed call requires 2-minutes to repeat the attempt on JT65-HF, and if this is repeated 5 times then 10-minutes will have transpired. That is enough time to loose propagation to a DX station and may result in a missed opportunity for the station that is attempting to work another station. If you're local (i.e. not DX), never call a station over their attempt to work DX.
Avoid causing QRM. Watch your waterfall display prior to transmission. If another mode is visible, even if you are not copying the mode being rendered on the waterfall, common courtesy would have you avoid using the same portion of audio spectrum as the station being rendered.
There are cases where available bandwidth make this practice impractical. The 17-meter band is an example where multiple overlapping modulation schemes that are associated with differing digital modes are common.
Verify that the transmitter ALC is not placing artifacts into the transmitted audio. This can be heard on a receiver and usually is indicated by clicking sounds during transmission. ALC modulation is indicative of overdriving the transmitter.
Set your CPU Clock correctly for JT65-HF. JT65-HF is a time synchronized protocol. Part of its success in working well below the noise floor is not only knowing where to look for a signal, but when to look for a signal. Mac OS X users need only activate network time synchronization in the System Preferences. For other operating systems, additional applications are available to make sure that your CPU clock is properly synchronized.
Apply proper modulation levels. Many transceiver manufacturers recommend setting the power level of the transmitter to 50% or less of the transmitters maximum rated output. The goal of the manufacturer is to avoid component failures and service costs. This is not necessarily the best approach to digital operation however as this procedure does not avoid over-modulation or over-driving the transmitter. It is better to leave the transmitter output level set to maximum and then reduce the audio drive from the computer audio interface to a level that results in an output power level of less than 50% of the transmitter maximum rated output. This procedure will result in avoiding over-driving the transmitter and avoiding exceeding the transmitter rated output for a 100% duty-cycle transmission. Further, your transmit signal will likely have less harmonic distortion and will result in a higher success rate of being copied by other stations.
Avoid having the AGC destroy your QSO. When operating in a digital mode, it is common for the receiver band-pass to be wide open. This enables simultaneous copy of multiple stations and enables the operator to be able to detect more stations that are candidates for a QSO. However, this procedure is not necessarily the best procedure for working weak stations, such as DX stations.
If a strong signal appears within the pass-band of the receiver, that strong signal can cause the Automatic Gain Control (AGC) circuit to reduce the receiver sensitivity and this reduction in sensitivity can cause a weak station to be attenuated to the point where copy is no longer viable.
The following image shows a strong signal (see white circle) that causes the AGC to reduce the receiver sensitivity. Note that all other signals within the receiver bandpass are also attenuated.
If your S-Meter is moving, you're almost certainly experiencing reduced sensitivity due to AGC operation. When the AGC responds to a strong signal and causes a weaker signal to be attenuated, there are two options available to enable continued copy of the weak station:
Apply a notch filter to reduce the signal strength of the strong station so that the AGC no longer reduces the receiver sensitivity.
The following image shows the AGC responding to a strong signal (lower white arrow) and reducing the receiver sensitivity across the entire receiver bandpass. At the upper arrow, a notch filter is activated to attenuate only the strong signal and this results in the AGC increasing the receiver sensitivity across the receiver bandpass. Notice how the signal in circled in green was strongly attenuated by the AGC response to the strong signal (bottom arrow) and then became visible again once the notch filter was activated (top arrow).
Note that this procedure, using a notch filter to attenuate a strong signal that is causing the AGC to reduce receiver sensitivity, will only work when using a manually tuned notch filter. An automatic notch filter will attempt to filter any coherent tone, including the digital modulation that is being decoded.
Reduce the bandwidth of the receiver pass-band and center the pass-band on the weak station that you wish to receive. The following image shows the receiver passband reduced to encapsulate the station being worked. The adjacent station signal strength was S9 + 20 dB and had been causing the station being worked to be attenuated to a level where copy was not possible. Once the bandpass was reduced, the adjacent station had little effect on the AGC and copy of the station being worked was restored.
If your working a weak station and are having difficulty, and if your radio supports it, try disabling the AGC. If there are no strong stations then you may not experience front-end overloading and may be able to finish your QSO. This is not recommended for most situations but may allow you to successfully finish a QSO with a weak station.
It is not unusual to implement both of the above solutions simultaneously, especially in crowded band conditions, in order to successfully work a weak station.
Help station operators with poor emissions. Since most stations do not have a capability to verify that emissions are avoiding being over-driven, over-modulated and have a sufficiently low intermodulation distortion, it is incumbent on us as radio operators to notify a station operator if we observe the effects of such emissions. The effects are quite apparent on the waterfall display as they will exhibit themselves as mirror images of the transmission that usually appear at lower frequencies on the waterfall display than the primary operating frequency or as a occupying a much wider bandwidth on the waterfall display than is common for the particular operating mode.
The following image shows a station exhibiting over-modulation of a PSK31 signal. For stations using the FlDigi application, the intermodulation distortion (IMD) is displayed at the bottom of the window for the selected signal. This particular signal had an IMD of -9 dB. For PSK31 signals, the desired IMD is to be at least -19 dB down.
The issue cannot be fixed if the station operator doesn't know there is a problem. It is good advise to notify the operator and then work with them to make the proper adjustments to remedy the problem. Cleaning up the offending emissions will result in reduced interference, a more copyable signal and improved success in contacting and working other stations.
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