The Voyager 1 stuck memory bit code relocation workaround

[gary]

On 14 November 2023, Voyager 1 began sending gibberish back to Earth.

In March 2024, engineers discovered the cause was a stuck bit in one of the
memory chips. Probably damaged by cosmic rays. Engineers had to relocate
the code that was occupying the memory space with the stuck bit. But finding
a new memory space required some juggling, including freeing up some space
occupied by code for communicating at higher Baud rates when the spacecraft
was closer to Earth.

Story at the Institute of Electrical and Electronics Engineers (IEEE) by
Gewndolyn Rak :-

https://spectrum.ieee.org/voyager-1

[xelasnave]

Thanks Gary for posting that interesting stuff.

It is such a joy to visit and find interesting stuff ... and to think busy folk such as yourself take their precious time to inform others about something they find interesting says something nice about that person.

[heygra]

Thanks Gary for that infomation.
I had read that Voyager 1 was sending back gibberish infomation.
It is great news to hear that they have been able to fix the problem from so far away.

[Dennis]

Thanks Gary, I guess that this remote access solution is more reliable and effective than having an on-board astronaut do the fault finding and code changes.;)

Dennis.

[Crater101]

I'd heard about this but hadn't read the story. Many thanks for the post, fascinating stuff.

[ronson]

Thanks for sharing Gary. An amazing story and it's fascinating to read the challenges they are facing fixing a 50+ years old technology remotely. And all the comms possible thanks to a dish just outside Canberra :)

[JA]

Ah....... the old 7 bit byte.

Best
JA

[gary]

Hi Alex,

Thanks for your kind words.

Best regards

Gary Kopff
Mount Kuring-Gai NSW

[xelasnave]

Hi Gary
You are more than welcome and I add it was not only your post here but you have brought so much stuff that I did not know about I can truely say I am much more more knowlagable in many areas thanks entirely to you...and I greatly appreciate the opportunity of being on the same forum...you are a very clever chap well educated well travelled extremely interesting and you hold my respect and admiration ...and you must know me well enough to know very well that few get to that impossible level in my book.:thumbsup:

So what else have you got;)

alex

[gary]

Hi Alex,

Thank you so much for your kind words. I'm truly grateful for the opportunity
to share and learn together on this forum. Your appreciation means a lot to
me.

Best Regards

Gary

[gary]

LOL!

My previous boss, Ray. Now he was smart. He passed away in January 2020.

Born in West Australia, he was the son of a letter sorter at the General Post Office.

He received a Government High School Scholarship to enter Perth
Modern School in 1948.

As a physicist he lectured in Copehagen before working at Bell Labs
in New Jersey.

He was the first to experimentally observe the quantum well effect
and co-invented the quantum well laser (https://en.wikipedia.org/wiki/Quantum_well_laser), which are used to power the
optical fibres of the Internet.

He played a seminal role in the invention of an ultra-fast type of transistor
known as the High Electron Mobility Transistor (HEMT).

Fabricated in Gallium Arsenide, we all have one in our smartphones.
In fact HEMTs makes it possible for cell phones to communicate wirelessly.

HEMTs only work because of quantum mechanics. In fact they utilize that
quantum well phenomena that Ray was the first to experimentally
demonstrate.

They are used in the receivers of satellite dishes including the giant
satellite dishes that form the Deep Space Network for communicating
with space probes.

The quintessential Aussie you never heard of who became an ex-pat but
went onto a daunting career of achievements, he was a Bell Labs Fellow.

He said there were fewer Bell Labs Fellows working at Bell Labs at the
time than Nobel Laureates. As the manager of the III-V semiconductor
laboratory at Bell Labs, he put forth the idea that led his team to win the
1998 Nobel Prize in Physics.

He was very modest but told us the thing he was proudest of was that he
had hand fabricated a pair of special ultra high-speed transistors that were
onboard the Voyagers.

"Long after I am gone", he would tell us, "They will still be out there".

[xelasnave]

Thanks Gary...I just loved that story.

It reminded me of a past next door neighbour without who TV would have not arrived so early in Australia....just a quiet guy but brilliant.

Where can I buy your book?


alex

[PCH]

Gary, I completely agree, that is a truly fascinating story. You sure have mixed with some ‘greats’ in your career ! Thanks for sharing the story.

[ChrisD]

I found this image of the Voyager 1 team celebrating the return of data after the modification. Definitely a lot of experience around that table!

I guess they can't retire until the RTG runs out.

Original article here: nasa-voyager-1-spacecraft (https://www.npr.org/2024/04/23/1246392066/nasa-voyager-1-spacecraft-talks-back)

Chris