DX Reminder Bands and Modes: Reminders That Ring Only When It Counts

The more precisely you tell an alert app what you want, the less often it disturbs you for things you do not. In LY4A DX Reminder that precision lives in one place: the table of DX Reminder bands and modes that you fill in for every callsign. It looks simple, a grid of ticks, but it hides a number of useful details, such as keeping 20 m CW apart from 20 m FT8, telling FT4 from FT8, and storing an exact frequency for a combination even when it is switched off. This guide explains how the table works, what each choice means and how to build sets of reminders for the situations that radio amateurs meet most often.

The Table: Thirteen Bands, Five Modes

For each callsign the app offers the HF bands from 160 m to 10 m, which includes 60 m, and the three bands above them, 6 m, 2 m and 70 cm. That makes thirteen bands. The modes are CW, SSB, FT8, FT4 and RTTY, five in all. Every pair of a band and a mode is a separate combination, and with thirteen bands and five modes there are sixty-five of them. The people who wrote the app say in the list of changes that the older presentation, in which each combination was a chip of its own, became a wall once 60 m and FT4 had been added.

Since version 4.4 of the Android app, the reminders are shown as a table again, the same as on the iPhone. The band is named once on the left, and the five modes stand in columns, so a single line answers the question of what is on for twenty metres. You tick the cells you want. A callsign with a tick in the 20 m row under CW and under FT8 will ring for those two combinations only. The basic steps of installing the app and adding the first callsign are in our article on automating DX spot alerts and on the LY4A site.

Each Cell Is Independent

The point of the table is that a cell is a promise about one situation. A tick on 40 m SSB means: ring when this callsign is reported on 40 m in SSB. A spot on 40 m CW does not fire it, and neither does a spot on 20 m SSB. The same holds for the alarm limit: the app gives one alarm for each callsign, band and mode, so a single appearance on the air, which dozens of spotters report, produces one alarm for the newest of the spots. How often the same combination may ring again is your choice, from every new spot up to every 60 minutes, and it applies to that one combination, so every other one still rings at once.

This independence is also the reason why you should not tick everything. A callsign with sixty-five ticks will ring on every band and in every mode where it appears, including combinations in which you cannot work it. A good table has the ticks of the bands you can use, and the bands where the propagation can realistically bring the station to you.

Real CW Only, and FT8 Apart From FT4

Two rules of the app save much confusion. The first is that CW means real CW only. Digital signals that share a band segment with CW are not counted as CW, so a CW reminder is not triggered by a stream of FT8 spots on the same band. The second is that FT4 has its own channels and is told apart from FT8, so a reminder for FT8 does not ring for FT4 and the other way round. The list of changes records this as a feature added together with the 60 m band and the FT4 mode in the Android and desktop versions.

The practical advice follows from this. If the expedition operates both FT8 and FT4, tick both on the bands where you want to work them, because one does not imply the other. If you only run FT8, tick only FT8. You can check the usual dial frequencies of each in our list of FT8 and FT4 frequencies by band, and learn how the two modes differ in the guide to FT4.

Frequency and Tolerance per Combination

Every combination can also carry an exact frequency and a tolerance. This is useful when you want to hear about a station only when it is near a certain frequency, for example the planned frequency of a DXpedition or the frequency of a beacon you track. The app stores both values for the combination. A detail from version 4.4 deserves attention: switching a combination off keeps its exact frequency. Unticking a combination in the edit window used to delete the frequency and tolerance set for it, and it is now only switched off, so ticking it again brings the frequency back.

This changes how you can use the table over time. You can prepare a full set of combinations with frequencies before an expedition, switch off all those that propagation will not support today, and switch on others as conditions change, without entering anything again. When you are not sure of the frequency, leave it empty and let the callsign ring for any frequency on that band and mode.

Sample Reminder Sets

The following sets show how the table is used in practice. They are examples; adjust them to your station, your antennas and your time zone.

A DXpedition that operates on many bands

Add the callsign once, and tick the bands where you have a good antenna and the target is likely to be audible at your time of day: for example 20 m, 17 m and 15 m by day, 40 m and 30 m in the evening. Tick CW and FT8 in each row, and add SSB on the bands where you have enough power. Leave 160 m and 80 m unticked unless you have an antenna for them and a quiet night. Our guide to working a DXpedition explains how to find the plan of operation.

Chasing a new one on 6 m

On the magic band, openings are short, and the stations you need are often reported in only one or two modes. Tick 6 m with SSB, CW and FT8, and set the repeat time short so that you hear every new spot. This is a case for a one-minute check interval. Background on the band is in the 6 metre band guide.

A rare RTTY station in a contest weekend

During an RTTY contest, many stations are reported at once, but the one you want is a single callsign. Tick RTTY on the bands of the contest, and consider a longer repeat time of 10 or 30 minutes, so that the phone does not ring each time the station is spotted by another contestant.

A low-band watch for the night

For a night when you want to be woken, tick a single combination, such as 80 m CW, for the one callsign that you must have. Make the repeat time long, and check the phone settings in the evening. Everything else stays off.

Thinking in Rows and Columns

A useful way to plan the table is to ask two questions in turn. The first concerns the rows: on which bands can I realistically hear and work this station from my location, in the coming days? The second concerns the columns: in which modes can I work it with the equipment I have? A station with a vertical and 100 watts has different answers than one with a beam and an amplifier. If you have only a simple antenna for the low bands, the 160 m and 80 m rows are best left empty, however exciting the target. If you work mostly digital modes, only the FT8 and FT4 columns may be needed.

It helps to think of the table as a set of filters. The row filter removes the bands that do not suit you, the column filter removes the modes, and the optional frequency filter removes everything outside the range you care about. What is left is the list of situations in which you really want to be told. With a good table, a ringing phone means that you should go to the radio, and not that something has happened somewhere in the world. For wider background on how the amateur bands are shared among the modes, see the overview of amateur radio frequency allocations.

Think too about time. A table that is right for the weekend of an expedition may be wrong a month later, when the target has gone and the season has moved on. Some users keep a small number of saved patterns in their notes, one for a typical DXpedition, one for 6 m, one for a night watch, and rebuild the table from the pattern when needed. The app keeps the frequency for combinations that you switch off, so you only have to tick the cells that apply, which takes seconds. This is a good use of the fact that switching a combination off keeps its frequency.

Finally, check that the mode you tick is one that the spotters actually report. Most DXpeditions are spotted in CW, SSB and FT8, and RTTY spots are rarer outside contests, so a reminder for a mode that is hardly ever reported will seldom ring. That is not a fault of the app, only of the data. Tick the modes in which the station is known or likely to operate, using the announcements before the trip as a guide, and add others only if you really intend to work them. For the digital side in particular, you can read the background of the mode itself on FT8.

Keeping the Table Tidy

Review your reminders once a week. Remove callsigns that you have logged, and switch off combinations that are no longer sensible, such as bands that the propagation does not support in the current season. The solar cycle and the season change which bands carry DX, as our article on seasonal HF propagation explains. A tidy table means fewer alarms and more attention for each one.

Remember also that the bands and modes you tick apply to the callsign, not to the device. If you use the app on a phone and on a computer, each has its own list, so set the table on the device that is nearest to you when the opening comes. Your callsigns and reminders survive an update of the app, so the work of building a good table is not lost.

The Bottom Line

The band and mode table of DX Reminder has thirteen bands and five modes, which gives sixty-five independent combinations for every callsign. CW means real CW only, FT4 is kept apart from FT8, and a switched-off combination keeps its frequency and tolerance. Use the table to ring only for the bands and modes that you can work, build a separate set for each situation, from a many-band DXpedition to a night watch on 80 m, and review it every week. A short and precise table is the best protection against alarm fatigue.

Frequently Asked Questions

How many bands and modes can I choose in DX Reminder?

Thirteen bands, from 160 m to 10 m including 60 m plus 6 m, 2 m and 70 cm, and five modes: CW, SSB, FT8, FT4 and RTTY.

Does a reminder for FT8 also ring for FT4?

No. FT4 has its own channels and is told apart from FT8, so you tick each mode separately.

Will a CW reminder ring for digital signals on the same band?

No. CW means real CW only, so digital spots do not trigger a CW reminder.

What happens to the frequency if I untick a combination?

The combination is only switched off. Its exact frequency and tolerance stay saved and return when you tick it again.

Can I get one alarm per band and mode?

Yes. The app gives one alarm per callsign, band and mode for the newest spot, and you choose how often the same combination may ring again.

Why should I not tick every combination?

Because you would be alarmed for bands and modes where you cannot work the station, and frequent useless alarms teach you to ignore the app.