HEX Problems

[mikemalone]

Apologies for the long-winded post. I came up against a strange problem. The transponder (Dynon 262) has to be ground tested. I have a Dynon ADSB 472 and a Dynon GPS 250. The recommended testing method involves the purchase of a USB RTL820T based TV tuner dongle and aerial - in my case a NooElec NeSDR Nano 2. An App can be downloaded and all transponding aircraft can be seen on the App. When your particular aircraft is identified on the list of transmitting aircraft, a report can be downloaded showing the aircraft’s position etc., printed off and sent off to be approved by the regulatory authority. My aircraft registration is G-RVMM and my allocated HEX code is 4077BD. I initially input this information into Dynon Skyview HDX 1100 as G-RVMM and HEX code 4077, as I couldn’t figure out how to input 4077BD. When it came to the test, my callsign showed up as GRVMM but with a HEX code of 435432 - but its GPS position was correct. When I returned to the aircraft, magically, the HEX code was indeed set to 435432. How this happened is a mystery to me. I changed the HEX code in Transponder setup back to the correct HEX code of 4077BD (I had by now figured out how to set the letters B and D in the HEX code). On re-testing, my aircraft could be seen, but still with the wrong HEX code of 435432. I returned to the aircraft, checked the transponder settings and noted that the correct HEX code of 4077BD was still retained in the transponder setup. Dynon have suggested that I may have inserted the letter O instead of a numerical 0. Others in the UK have suggested deleting the HEX code, powering down and starting again. Anyone have any other suggestions, has this happened to you? Best regards, Mike Malone UK

 

[Rhino]

Where are you getting 4077BD? The image you attached doesn't indicate that. However, 435432 is indeed the ICAO code for your aircraft.

I would try deleting the tail number and restarting. Hopefully that will delete the hex code, and you can try again. Out of curiosity, what software version are you running?

 

[RVDan]

The UK registry database shows 4077BD as the hex code for G-RVMM. Like the OP says, it seems like the Dynon internal database has a problem and is providing the wrong code. Octal for this registration should be 20073675. Question, have you tried entering the dash between the G and R? The UK registration database shows the dash.

 

[Rhino]

Yes, I know the registry. I just wanted to know his source. His OP indicates he already entered the dash. The Dynon doesn't use octal. It's base 16 hex only.

 

[RVDan]

I saw the report that says GRVMM no dash. It might just be the report format.

 

[Rhino]

Probably is.

 

[mikemalone]

Thank you all for your inputs. Never did figure out where the HEX code of 435432 came from. I think Octal and SkyView software version inputs were red herrings. But thanks, anyway, for these suggestions. In the end, taking some of the advice from above, I deleted the HEX code in the Skyview, powered down the system, powered back up, entered the correct HEX code of 4077BD, saved it, powered down and powered up again and all was fine. The NeSDR Nano 2 picked up my registration and correct HEX code and showed the aircraft positioned in the hangar at Enstone airfield. Obvious really, but not to me at the time. Many brains make light work. Thanks again.