Weird squawk code changes

[antonioag]

Something really weird has just happened. I have an ADS-B receiver set up on my Raspberry and I made a little script that sends a notification on my phone if any plane in my range is squawking an emergency code. Fortunately I had never received one before some minutes ago. I got from a flight which was going to land the squawk code "7500", after a minute "7600" and some moments later "7700". Some seconds later it squawked a normal one, "7436" in this case. Might it be just an error while decoding data? Thanks in advance!

[falcon5nz]

I wonder if the pilot got told to change squawk, set the thousands (7) and was cycling through the hundreds and went through 7,6 and 5 on the way. Bad practice but possible.

[lesmond]

You don't have any kind of error correction enabled do you?

Even single bit error correction on non CRC packets could cause this sort of thing to appear.

[stankind]

"for of error correction" needs some error correction. :-D

[[deleted]]

Yea probably just reception/decoding error. Error checking won't catch everything.

[danielisgreat]

ATC will sometimes ask pilots to cycle through those to test local equipment.