QO-100 Dx Club database callsign filtering

Dear QO-100 Dx Club Member

We would like to share with you the QSO validation process so every member is aware of the current rules.


When we decided to embrace this project, we knew in advance the most difficult part to handle was the Rankings/Awards. We had 3 options:

  • DXCC style: paper QSL confirmation -> QSL verification -> Award issue/listings. This was not desired because it does not reflect the QSO activity, but only those who pursue QSL collection (decreasing by the day)
  • LOTW style: electronic confirmation -> record verification -> Award issue/listings. This was (an still is) our favourite option. Unfortunately it only works if a massive number of operators upload their logs.
  • ADIF log: user ADIF -> Log upload -> Award issue/listings. This is not ideal (because there is no verification mechanism) but we thought that was not a major issue. After all, most of amateur radio activity is based on trust.

We choose the last option and focused our attention on the log import issues.


As we mentioned on the previous communication, as soon as the website was launched, we realized getting the right DXCC was a major problem and decided to use Clublog API. Using this means every time a log (adif file) is upload to our website, we forward the callsign to Clublog and in return we receive a code. From Clublog’s reply, we classify the DXCC as:

  • XYZ : DXCC entity code according to ADIF version 3.1.2
  • 0 (zero) : These are usually /MM stations. They do not count for DXCC, but count for grid locator ranking.
  • -1 : Invalid callsign. The call remains on the database but it’s not valid for our Awards/Rankings.
Note: In some particular cases (currently AO50UPC and AO50MOON) we discard the Clublog information and replace it with our own information.
Once the DXCC is sorted, our database goes thru a daily check up process:

DXCC under QO-100 foot print? 

The moment we start receiving logs, we immediately noticed reports of QSO with DXCC that are not even under the sat footprint! This was mostly due busted calls. So we made a list valid DXCC under QO-100 footprint. If the callsign does not belong to those DXCC, the call remains on the database but it’s not eligible for our Awards/Rankings.

DXCC active on QO-100? 

For the same reason stated in before, we also noticed reported QSO with DXCC that were never active on QO-100. So we created a QO-100 Active DXCC list. If the callsign does not belong to those DXCC, the call remains on the database but it’s not eligible for our Awards/Rankings. Please note that this list is maintained manually. So, if a QSO with a DXCC never active before over QO-100 is uploaded, it will not show on the rankings/be available for the awards until we enable that DXCC on the list.

Is the Callsign correct?

Unfortunately many are not. So we establish a list, where we manually identify wrong callsigns. If a callsign is flagged on that list, the call remains on the database but it’s not eligible for our Awards/Rankings until you submit a new adif file to fix the problem.

3 QSO rule

However soon we realised it’s impossible to check every single callsign on our database (currently 5832), so recently we established a new rule: if the call is not listed on, at least, 3 QSO, the call remains on the database but it’s not currently eligible for our Awards/Rankings. However, it will become eligible:
  • automatically, when it’s listed on 3 QSO
  • manually, when you confirm (via email) the call is correct (eg because you received a QSL card, LOTW, eQSL, etc).
Please note: if the call is flagged on this list, beside the DXCC, the Grid is also not eligible for our Awards/Rankings

# Grid Locator

If the callsign survived until this point, then we start the Grid locator check-up.
We would like to stress this was a much bigger problem that we anticipated. To give you an idea, currently there are 1162 unique grids on our data base. However, after all the filters applied, only 659 are valid! Let’s understand how we reached this number.

Grids not covered by QO-100 footprint.

If the reported grid starts by A, B, C, D, E, F, P, Q or R, the QSO remains in the database but it’s not valid for our Awards/Rankings (because those grids are not covered by QO-100 footprint). You can, however, submit a new adif file to fix the problem.

Grid does not match DXCC

Many reported Grids are not covered by the DXCC. In this case, the QSO is flagged but remains on the database and it will not be valid for our Awards/Rankings until the correct grid is reported.
Please note: despite our extensive search, we can’t guaranty the list to be 100% accurate (specially EU/AS Russia and border areas). If you come across any error, please do let us know. Thank you.

Grid Check List

Despite the previous filters, there were still many grids wrongly reported. So we implemented an additional check list. Because this list is manually maintained, it’s subject to error. So if you don’t agree with any grid exclusion, do let us know and we analyse the problem.
Reached this point, it’s obvious the numbers will change on the tables! However, (unless some stations have a huge number of errors), the relative positions should remain, as the criteria applies to all the same way.
So, what can you do now? Search for errors and fix them.

How can we help?

Log  Upload

Every time a log is upload to the website, a report is generated and sent by email. Please check it and fix any problem.

QSO with Issues.

On your Profile menu there is a new section called QSO with Issues. Please check it, to be aware of all the issues we found on your log.  If you have any doubts, or do not agree with the report, do let us know and we will evaluate the situation.
We hope now you better understand the reasons behind the filtering process and support us on the quest for more accurate and fair ranking process.
73 de QO-100 Dx Club team (Hugo and Costa)