Selfspotting on SSB by CW CQing on SSB desired QRG

Dear all,
It’s been written several times on this Reflector that SOTA operation on SSB is hard when it’s not possible to have cell phone signal available from a summit and the operator can’t selfspot.
It’s definitely true and even when having cell phone signal available, the fact of having to type the info on the phone to raise a selfspot in the cold, wind and/or rain, produces a certain upheaval to the operator as well as a waste of some valuable time.
I have been thinking about possibly CW calling CQ SOTA on the chosen SSB frequency, as to be copied by the RBN and be automatically spotted by KU6J after a couple of CQ SOTA calls and then switch to SSB to continue calling CQ SOTA on voice until the first chasers had seen the new spots and show up on my SSB frequency.
Have any of you ever tried this?
Do you think there would be any problem with KU6J due to CW calling CQ on a SSB part of the band?
I guess not, because CW is allowed all over the band.
Of course, with this method the spot would be raised on CW but the fact of being spotted on a typical SSB frequency should tell the chasers that there may be a phone activation just started on that frequency.
Any comments will be very welcome.
Thanks in advance and best 73 de Guru - EA2IF

Many if not most of the CW skimmer radios are only covering the CW portions of the bands. So your CW may not be heard by a skimmer.

I was thinking of building this feature in my homebrew rig for the micro to control send a pre-programed morse string - a bit like QRSS works but faster, but as Andy describes the skimmer from KU6J wont be much use here.

BUT … someone could create a new skimmer to do exactly this.


Yes, Jonathan, that’s exactly what I was thinking on for those not able to transmit on morse code, just a short memorised CQ CQ SOTA CALLSIGN to be transmitted a couple of times and the skimmer should be able to pick it up and the spot be raised immediately.
Andy is right and I had not thought about the problem of SSB segments of the band not being covered by current skimmers, but as you very well pointed, this is possibly the perfect reason for creating specific SOTA dedicated skimmers covering the typical SOTA activation segments…
Great idea, Jonathan!
Anyone willing to try this out? :slight_smile:

Best 73 de Guru - EA2IF

Dear Guru,

a bit off topic and does not solve all of our issues: What about APRS? In case there is APRS coverage on the summit, this is also an option to get one’s selfspot in SOTAWatch.
Stewart, G0LGS has set up a service monitoring APRS traffic in the internet backbone and extracting messages to SOTA which show up as spots afterwards. For details see SOTASpots. In lucky cases (Internet to HF IGates) you even get a acknowledge message
Of course this requires some gear to send APRS packets. I use the Kenwood TH-D72 (handy, but expensive) but any 2m FM transceiver coupled with APRSdroid should also be ok.
I have preset the correct syntax of the message so I only have to change frequency and summit reference on site. Ok, some playing around on the radio, but acceptable.

73 de Michael, DB7MM

Its strange Guru, Because I was actually thinking about this at lunchtime, and then you created a post on the same subject matter.

On a recent summit I had no GSM coverage at all, I also do not like being dependent on having access to GSM either. But as far as correct and instant spotting is concerned apart from the APRS system which I think they use in marine communications Michael ? There is not much else one can use apart from rely on a chaser spot which is often the case.

Could be an interesting system to implement at least on HF. Could even send a PSK31 packet with the data in it, which in turn could be generated by your smart phone.


My satellite based spotter uses Iridium SBD messenging and works a dream. The downside is the cost of about 16p per spot + 8ukp/month for an airtime contract. But it works worldwide and as long as you have a clear view of the sky you can get a spot to SOTAwatch in about 20secs.

Just include in your comments on your alert that you will send a CQ SOTA on 14.0615 or such frequency to alert your activation and then list your SSB freq. The guys can figure it out.

We will hunt you down! Smile.

John N0EVH

Good Morning Guru

I’m fairly certain the CW Skimmer SDR software is only looking at the first 100 khz of each band. See for the latest info by N4ZR.

So a CW CQ in the SSB portions of the bands would not be heard by the RBN network and therefore not picked up by Eric’s software/SOTA Spot.

Good question however.

Regards, Guy/n7un

I believe these already exist.
They are called chasers :smile:
Pete :gb:

Lots of ops already do this.
They call CQ on CW, get spotted by RBN, work the pile up and then send nw qsy ssb 7118 aprx pse spot tu up…


You are right, although I think it’s not just chases but kind chasers raising a spot when they copy (and after they have worked) an activator CQing with no takers.
Best 73 de Guru - EA2IF

Guru, I thought I had proposed an SSB spotting system that used RBN, here is the original text:

In case you don’t know John G4YSS often operates a club call sign G0OOO (in Scotland GS0OOO)

The idea being you tell a chaser to look out for spots on CW of an alternate callsign and to spot SSB when they see the RBN spot. By multiplying the CW call frequency by 10 in SSB spot, the chaser who is monitoring knows which SSB frequency to spot. The alternate callsign being the key for the chaser watching that you intend to call on SSB.

It’s contrived and requires someone to know what to do and to look out for the special spots, but it would fit in with where skimmers are listening.

Thanks, Andy. Yes I saw your proposal when you wrote that spot some time ago and it’s an idea, IMHO, a bit complicated to put in practice, as the activator would have to find a clear frequency for his SSB activation, then calculate the difference in KHz agreed with his colleague, go down to the calculated frequency on the CW segment, call CQ as to be copied by skimmers and spotted by KU6J, then go back up to the previously chosen frequency for SSB operation hoping that it still remains clear and start calling on voice hoping that your colleague has seen the CW spot, has done the right calculations and has risen a new spot for the SSB frequency.
It may work sometimes for sure, but it’s a bit too complicated and requires a significant dose of good luck.
Something more robust and automatic is what I was thinking about.
I know you know it… :wink:
Best 73 de Guru - EA2IF

No reason for anything this complicated. I am sure a specific skimmer can be employed for SSB and it would make a great project for somebody.

Slow Speed morse - QRSS would be very easy to scan and have a high success rate, all the operator needs to do is send at a slow rate - easy for anybody with knowledge of the basic character set, the error timing between the dots and dashes can be wide enough for it to work with manual sending.

It happened with me again today, I didn’t have any GSM signal, in the remote parts of NW. I had to give instructions to a non-SOTA operator to spot. I don’t want to have extra hardware with me just to do this. There is no technical reason why this can not be done. Learn some basic CW is the only catch, you don’t even need to send it fast. A very tempting project …