RBNGate - Automatic SOTA Spotting by KU6J 


RBNGate is software designed to automatically spot Summits On The Air (SOTA) CW activators to Sotawatch as soon as they call CQ SOTA on any CW frequency. RBNGate works by monitoring spots from the Reverse Beacon Network (RBN), which is a world-wide network of stations (known as "skimmers") that are equipped with wideband receivers and Alex VE3NEA's CW Skimmer software. The skimmers automatically spot any station heard calling CQ, whether they are calling CQ DX, CQ SOTA or just CQ by itself. Most skimmers monitor only the HF bands, but some monitor the VHF bands as well.

When RBNGate receives a new spot from RBN, it checks to see if the callsign and time match any Sotawatch alerts. If a matching alert is found, it sends a spot of the activator to Sotawatch (if the activator has not already been spotted on that frequency). The Sotawatch spot's summit reference number is set to the one from the alert. The spot's comment includes additional information, such as the callsign of the skimmer that first heard the activator, their signal-to-noise ratio at the skimmer (in dB), and their approximate speed in words per minute. If the activator changes bands or changes frequency by more than 1 kHz, RBNGate will spot them again (if not already spotted on the new band or frequency).

Activators who spot themselves will also be tracked and spotted by RBNGate, even if they have not entered an alert for their activation into Sotawatch. Activators can also use self-spots to override their alerts in instances where they find themselves running late, decide to activate a different summit, etc.

If you find that automatic SOTA spotting improves your SOTA experience, then please consider making a donation to Reverse Beacon Network via the Donate button at the bottom of their home page (I am not affiliated with Reverse Beacon Network and receive nothing from them if you choose to donate). If you are an activator who prefers to not be automatically spotted by RBNGate, please E-mail me your callsign and I will add you to the opt-out list.

Frequently Asked Questions

Can RBNGate spot me on any summit anywhere in the world?

Yes, assuming that you are within the range of at least one RBN skimmer.

How many skimmers are there and where are they located?

There are hundreds of skimmers around the world, but they are usually not all online at the same time. To see which skimmers are currently online and which bands they are monitoring, see the right hand side of the Reverse Beacon Network home page. More detailed information is available on their Skimmers page.

Do I have to format my CQ SOTA in any particular way for it to get spotted by RBNGate?

No, but it is best to send your callsign at least twice and to send the entire transmission at a constant speed. For example, either of these will work well:



How long does it take for RBNGate to spot me once I begin calling CQ?

This depends on how strong your signal is and how many RBN skimmers are within range and able to hear it. In my experience, I am usually spotted within a minute or two of finishing my first CQ, even when using only 5W.

Will RBNGate spot me on frequencies and bands other than the ones I specify in my Sotawatch alert?

Yes. RBNGate ignores the frequency and mode information in Sotawatch alerts.

Will RBNGate spot me even if I'm not on or near the usual SOTA frequencies?

Yes. The RBN skimmers typically monitor the entire CW segment of bands,and RBNGate doesn't care which frequency you choose to call CQ on.

What if my Sotawatch alert specifies only SSB or FM, will RBNGate still spot me if I decide to call CQ on CW?

Yes. RBNGate ignores the frequency and mode information in Sotawatch alerts.

What if I call CQ on CW but do so in the phone portion of the band. Will RBNGate still spot me?

No, it probably won't. The RBN skimmers usually only monitor the CW band segments.

I forgot to enter a Sotawatch alert, but I called my friend and she entered one for me. Will RBNGate still spot me?

Yes. RBNGate doesn't care who entered the Sotawatch alert. Note that it could take up to five minutes for RBNGate to see new or revised Sotawatch alerts.

I forgot to enter a Sotawatch alert for my activation, and none of my friends are answering their phones. Is there anything I can do to get RBNGate to spot me?

Yes, simply spot yourself to Sotawatch prior to going on the air. RBNGate will then spot you just as if you had entered an alert.

If someone has recently spotted me on a particular frequency, will RBNGate spot me there as well?

No. Prior to sending a spot to Sotawatch, RBNGate first checks to see if someone has already spotted you on that frequency. If they have, then RBNGate won't send its spot.

If I change to a different band or frequency, will RBNGate spot me again on the new frequency?

Yes, as long as you change frequency by 1 kHz or more, and someone else doesn't spot you to Sotawatch first.

If I stay on the same frequency for a long time, will RBNgate eventually spot me again on that frequency?

Yes. If an hour or more has elapsed since anyone spotted you on that frequency, RBNGate will spot you again. The amount of time that it waits before respotting a station on the same frequency is configurable and could change in the future.

What if I change bands, get spotted there, then return to the first band on the same frequency that I was spotted on earlier. Will RBNGate spot me?

Yes. The time interval between respots on the same frequency discussed in the prior answer (currently 1 hour) is ignored if you change bands, and a shorter time interval is used instead (currently 10 minutes, used for filtering out duplicate RBN spots). You were clearly not on the first band anymore if you were spotted on a different one, so when you return to the first band RBNGate considers it to be a new band/frequency.

The callsign in my Sotawatch alert is W1ABC but I may call CQ as W1ABC/P or W2/W1ABC/P. Will I still get spotted?

Yes. Portable designators are ignored by RBNGate when it checks for callsign matches between RBN spots and Sotawatch alerts, or between RBN spots and your self-spots. They are NOT ignored for the purpose of posting the spot itself: you will be spotted with whatever variant of your callsign that the RBN skimmer heard you send.

If I arrive on the summit early or late, will RBNGate still spot me?

Yes. The standard spotting window currently extends from 1 hour before your alert's estimated time of arrival to 3 hours after it , and you can extend it if you wish. You may also spot yourself to Sotawatch and RBNGate will spot you for 3 hours after your self-spot is received. Note that these spotting time window parameters are configurable and may change in the future as RBNGate is tweaked and tuned to provide the best experience for activators and chasers.

If I stay on the summit for a long time, will RBNGate continue to track and spot me throughout the activation?

Yes, the standard spotting window extends until 3 hours after your Sotawatch alert's estimated time of arrival unless you have extended it in your alert. If you need more time than that, self-spot yourself and the spotting window will extend to 3 hours after RBNGate receives your self-spot. You can continue to self-spot yourself every few hours and the spotting window will be extended to 3 hours after each self-spot's time of receipt.

Can I extend the spotting window?

Yes. The standard spotting window begins 1 hour before your alert's ETA and ends 3 hours after it. You can override these start and end times by including a S+n and/or S-n code in the comment for your Sotawatch alert, where n is the number of hours the spotting windows extends from your alert's ETA. For example, S+12 causes the spotting window to extend to 12 hours after your alert's ETA, and S-6 would cause the spotting window to begin 6 hours before it. The codes are case insensitive, you can choose to include either or both codes anywhere in your comment, and they need not be the only text in the comment. For example, this comment will work fine: "Camping on the summit. S-12 Should be fun! s+18".

Will RBNGate spot me on the correct summit if I have multiple Sotawatch alerts entered for the same day?

Yes, if you are generally on time in arriving at the summits. When a spot of you is received from RBN, RBNGate will match it to the alert that has it's estimated time of arrival set closest to when the RBN spot was received.

I was really late in getting to my first summit, and RBNGate spotted me on my planned 2nd summit of the day instead of the one I was actually on. Two chasers quickly spotted me on the correct summit. Why did RBNGate continue to spot me on the incorrect summit?

For the purpose of overriding information in Sotawatch alerts, RBNGate ignores spots made by anyone other than the activator.

What if I change my mind and end up going to a summit that is different  from the one in my Sotawatch alert?

You have two options:

  1. Login to Sotawatch and update your alert. This is the best option as it not only allows RBNGate to spot your correctly, but also reduces the chances of chasers being confused. Note that it may take RBNGate up to 5 minutes to see new or updated alerts.
  2. Spot yourself on the new summit prior to going on the air. When RBNGate receives your self-spot, it will use it to override your current Sotawatch alert(s) so that it spots you on the correct summit. Your "current Sotawatch alerts" are the ones in which the current time is within 1 hour before or 3 hours after their estimated time of arrival. If you have alerts entered for times farther out into the future, those alerts won't be overriden.

I'm doing a backpack trip this weekend in an area with no cell phone coverage. I'd like to activate some summits during the trip but don't know which ones they will be, or when I'll be on the air. Can RBNGate spot me throughout my trip?

Yes. Since you don't know which summits you will be activating, enter a Sotawatch alert and specify the summit using question marks such as "W6/NS-???" or "G/??-???". Enter an ETA that is near the beginning of your trip, then extend the spotting window by including a code such as "S+48" in the comment of your alert (this code extends the spotting window to 48 hours after your alert's ETA). RBNGate will now spot you on your 'to be determined' summit (W6/NS-??? or whatever you entered) whenever it hears you calling CQ during the trip. The chasers will know that they have to get the actual summit from you over the air. You could also choose to use the midpoint of your trip as the alert's ETA, then extend both the beginning and end of the spotting window with a comment such as "Backpacking all weekend in the Sierra. S-24 S+24". 

I accidentally spotted myself on the wrong summit. What do I do?

Spot yourself again but on the correct summit. Your later self-spot(s) will override earlier ones and RBNGate will once again spot you on the correct summit.

What if I get confused and send the wrong summit reference over the air, but I had it right in my Sotawatch alert? Which summit reference will RBNGate use?

RBNGate doesn't know what you send over the air so it will use the summit reference from your Sotawatch alert, or from your most recent self-spot if you sent one within the last 3 hours.

You've mentioned self-spots several times. Does it matter how I send those in (via Sotawatch web page, Spotlite, SMS, APRS, etc.)?

No. A self-spot sent via any of those methods are treated the same by RBNGate. If you use an APRS gateway such as APRS2SOTA, then the gateway either needs to set the "posted by" field to your callsign or to anything containing the characters "APRS" (e.g., "APRS" and "APRS2SOTA" both work fine).

What if I enter a Sotawatch alert for the following day, the weather ends up being bad, and I stay home and call CQ DX instead? Will I still get spotted as if I'm on a summit?

Yes. To prevent this from happening, either delete your Sotawatch alert or edit it to include any of the following anywhere in the alert's comment (without the quotes, case-insensitive): "canceled", "cancelled", "RBNN" or "NoRBNGate".

If I'm on a summit and want to tell RBNGate to stop spotting me, is there any way to do that?

Yes. Spot yourself to Sotawatch and include either of the following anywhere in your spot's comment (without the quotes, case-insensitive): "RBNN" or "NoRBNGate". This will disable spotting based on any of your current Sotawatch alerts or prior self-spots. Your "current Sotawatch alerts" are the ones in which the current time is within 1 hour before or 3 hours after their estimated time of arrival. If you have alerts entered for times farther out into the future, RBNGate spotting will resume for those. It will also resume if you spot yourself again and do not include "RBNN" or "NoRBNGate" in the comment for your self-spot.

Can RBNGate spot me on other modes such as RTTY and PSK31?

Yes. The Reverse Beacon Network is setup to work with the RCKSkimmer digital mode skimmer software written by DL4RCK. There are currently only a few skimmers running this software, but that could and likely will change in the future.

I saw RBNGate spot someone on the wrong frequency. Why did it do that?

The RBN skimmers occasionally have frequency calibration or configuration issues. RBNGate doesn't know what frequency you are actually on, and relies on the data it receives from the skimmers. If you observe a skimmer spotting a station on the wrong frequency, please E-mail me and I will add the skimmer to RBNGate's skimmer ignore list. I will also try to contact the skimmer operator to make them aware of the problem. If and when the problem gets corrected, I will remove the skimmer from the ignore list.

I saw RBNGate spot someone on the wrong summit. Why did it do that? 

This will happen under any of these circumstances:

  1. The Sotawatch alert for the activation specified the wrong summit.
  2. The activator spotted themselves on the wrong summit.
  3. The activator planned a multi-summit day and entered multiple SOTAWatch alerts, but was so late (or early) arriving at a summit that their on-air time was closer to the estimated time of arrival for one of their other alerts.

I spotted myself as getting ready to operate (e.g., "QRV in 10 min") but RBNGate didn't spot me once I went on the air and called CQ.  Why didn't it spot me?

RBNGate can't distinguish between Sotawatch spots for an activator who is just getting ready (e.g., "QRV in 10 min") vs. a  spot of them actually on the air. If you called CQ on the same frequency as your 'getting ready' spot, RBNGate would therefore consider the on-air spots from RBN as being dupes with the 'getting ready' spot in Sotawatch. To prevent this from happening, specify just the band in MHz in your 'getting ready' spot, or call CQ on a frequency that is 1 kHz or more away from the frequency in your 'getting ready' spot.

I want to enter a Sotawatch alert so that the chasers will know my plans, but I don't want RBNGate to spot me during that activation. What can I do?

Include either of the following anywhere in your Sotawatch alert's comment (without the quotes, case-insensitive): "RBNN" or "NoRBNGate".

My area doesn't have any RBN skimmers and I'd like to set one up to improve coverage. How can I do that?

You'll first need to get the CW Skimmer software and one of the receivers that it supports (supported receivers are listed on the CWSkimmer page). If you'd rather have your skimmer looking for CQ's on RTTY, PSK31 and other digital modes then get the RCKSkimmer software and one of its supported receivers instead. Once you have your skimmer up and running, you can add it to the Reverse Beacon Network by following the instructions on RBN's Getting Started page.

RBNGate is ruining my SOTA fun! I don't want it to ever spot me. What can I do?
E-mail your callsign to me (KU6J) and I can add you to the Excluded Activators list. This will prevent RBNGate from ever spotting you.