720 service bulletin ..... READ!! closed

[georgi UK]

=] as of SK update site, keeping you guys posted.....


Service Announcement Re: Logging Posted in News and Updates | Comments Off
It has come to our attention that a bug in the playback and vibration logging feature in the 3.10 firmware can cause auto-reset errors for SK-720 pilots. This issue does not affect the SK-540. This problem can be fixed by either turning logging off, or by swapping the existing SD card with a high-speed Sandisk card.
Please note that auto-resets do not shut down the SK-720 completely. The typical symptom of the auto-reset error is a twitch and sudden onset of drift during flight. Some users will encounter enough drift that cyclic and rudder inputs will be necessary to keep the heli level.
We are working on a firmware fix and will have it ready for customers ASAP.

more info from SK =

Again, apologies about this. The report that a faster sd card fixed it was from a dealer / beta tester, we have not yet confirmed it here, we'd prefer to focus on fixing it.

For the record, the SK is tested before every release that it will recover from a reset and be flying the heli in less than 1/2 second. It may take longer for the ESC to ramp back up, and the heli to be fully in control, depending on what was happening at the time.

[Groucho_]

This post should be on top and remain there until a new firmware is available...

[jhamel]

Georgi. Thank you for alerting us to this bulletin. That explains the issues that I am having.

Concerning the microSD card, are there any minimum or maximum requirements? Minimum/maximum speed and/or memory? Thanks.

[grimbeaver]

Originally Posted by johnahamelv

Georgi. Thank you for alerting us to this bulletin. That explains the issues that I am having.

Concerning the microSD card, are there any minimum or maximum requirements? Minimum/maximum speed and/or memory? Thanks.

It has to be a 2GB or smaller non SDHC type. Which is not real easy to come by these days. This is currently the only one SanDisk makes:
http://www.amazon.com/SanDisk-SDSDQ-.../dp/B001C30GTY

I'm pretty sure when I pulled mine once it was a SanDisk but I could be wrong. With the way I have the gyro mounted it would be tough to remove so I'll just disable logging for now.

However if you look in the other thread it sounds like it's not worth the effort:
https://www.helifreak.com/showpost.p...8&postcount=54

[jhamel]

Originally Posted by grimbeaver

With the way I have the gyro mounted it would be tough to remove so I'll just disable logging for now.

However if you look in the other thread it sounds like it's not worth the effort:
https://www.helifreak.com/showpost.p...8&postcount=54

I have the same issue with my mounting, where it would be awkward to get to the card, especially since getting a new card may not resolve the issue. I may just test for vibrations for the first one or two flights doing conservative flying high up, and then just turn the logging "OFF" until Skookum resolves the firmware issue. Thanks.

[Ken Here]

Before you go out buying new cards you might want to read Art's post yesterday.

[georgi UK]

=] have added this now to the opening post =

more info =

Again, apologies about this. The report that a faster sd card fixed it was from a dealer / beta tester, we have not yet confirmed it here, we'd prefer to focus on fixing it.

For the record, the SK is tested before every release that it will recover from a reset and be flying the heli in less than 1/2 second. It may take longer for the ESC to ramp back up, and the heli to be fully in control, depending on what was happening at the time.

[nickyd]

Had a quick test with the SK logger switched off and found that there was no incorrect swash movement when switching to self-level mode. It functioned perfectly the whole flight, switching in and out of Sl mode. Hands-off SL is now a reality again.

Previously, the self-level would sometimes be ok, and sometimes not, tilting the swash to the left when activated, all during the same flight. I had assumed it was a temperature issue and was not too worried, as I only used the SL for bailout purposes.

This is a great intermediate fix. Thanks for the info Georgi.

[yellow303]

Wow! that explains it all! I was soo ready to give up on the SK720. thanks for the info guys

[dhyayi]

Originally Posted by grimbeaver

It has to be a 2GB or smaller non SDHC type. Which is not real easy to come by these days. This is currently the only one SanDisk makes:
http://www.amazon.com/SanDisk-SDSDQ-.../dp/B001C30GTY

[/url]

Works fine, just as expected. I would buy this again in a heart beat if I had a need for one. Not much else to say.

[HFMan]

I have been having trouble with my SL feature, and disabling logging did NOT fix it. Here's what happens. When I first lift off and active SL, it works fine. After maybe 2-3 minutes, the SL begins to drift, and it refuses to stay level- it has a drift to the left and to the rear. After a couple more minutes, it's even worse- the drift is more like a moderate bank to the left and rear.

If I land, wait 15 seconds, then lift off again, SL is good again. But fly a couple minutes, and it again starts to drift backwards and to the left. This is VERY irritating! Anybody have any thoughts?

Oh, BTW- my vibration levels are good- the SK-720 has never disabled SL. Vibration log shows about 1.5-2.0 in normal IU flight, and upwards of 7-8 spikes when hammering the tail rotor or the collective.

[rmalt]

Could this cause a momentary drift in the tail in normal mode?

[Andy01]

This has probably been asked before - is there a way to roll back to an earlier firmware ?

I have just bought a new SK720 for a new 500 sized Huey, and it has 3.10 on it.

Both of my other 720s have an earlier firmware and they work well, so my preference would be to run the same firmware on all 3 (I have no interest in the new governor as I use the CC Ice governors, which are fine for scale), but I don't know how to install an older version. The only option I saw was "Check for updates".

In a new scale model I would certainly want to use logging, but I also use a very slow spool-up, so if the ESC reset, it would take potentially 20-30 seconds to get back up to speed, which I suspect might be too long, so in my book, this little fault seems to be potentially a fairly major boo-boo.

Colin

[georgi UK]

=] Colin hi, no roll back sorry, I see this as a short lived situation while SK get it fixed. hang in there mate!

[georgi UK]

Originally Posted by rmalt

Could this cause a momentary drift in the tail in normal mode?

=] don't think so?

[georgi UK]

Originally Posted by HFMan

I have been having trouble with my SL feature, and disabling logging did NOT fix it. Here's what happens. When I first lift off and active SL, it works fine. After maybe 2-3 minutes, the SL begins to drift, and it refuses to stay level- it has a drift to the left and to the rear. After a couple more minutes, it's even worse- the drift is more like a moderate bank to the left and rear.

If I land, wait 15 seconds, then lift off again, SL is good again. But fly a couple minutes, and it again starts to drift backwards and to the left. This is VERY irritating! Anybody have any thoughts?

Oh, BTW- my vibration levels are good- the SK-720 has never disabled SL. Vibration log shows about 1.5-2.0 in normal IU flight, and upwards of 7-8 spikes when hammering the tail rotor or the collective.

=] I think this is related to the new firmware that is needed, maybe not? send a log to SK for analysis.....

[Hans M]

Originally Posted by grimbeaver

It has to be a 2GB or smaller non SDHC type. Which is not real easy to come by these days. This is currently the only one SanDisk makes:
http://www.amazon.com/SanDisk-SDSDQ-.../dp/B001C30GTY

I'm pretty sure when I pulled mine once it was a SanDisk but I could be wrong. With the way I have the gyro mounted it would be tough to remove so I'll just disable logging for now.

However if you look in the other thread it sounds like it's not worth the effort:
https://www.helifreak.com/showpost.p...8&postcount=54

Why cant it be a SDHC ultra?? I can write 30mb/s Sandisk mobile ultra micro sdhc? you can get adapters.

[desertstalker]

Originally Posted by Hans M

Why cant it be a SDHC ultra?? I can write 30mb/s Sandisk mobile ultra micro sdhc? you can get adapters.

Because a SDHC is not a SD, you cannot use a SDHC card in a device not designed to accept one, it will not work at all.

The SK720 is also limited to 2GB FAT formatted, it cannot save files to any other type of filesystem.

[Gabriel Boivin]

My 720 has gone into auto reset a few times with recording-logging enabled.
I was test flying and recording for vibrations mostly in hover. The temperature was 25-27C.
The auto reset was kicking in at about 7.5 minutes.
I was assuming that my ESC or other hardware was the cause of the trigger of auto reset.
So I mostly flew early in the mornings or late evenings and there was no auto reset.
I read about the alert bulletin and turned off the recording-logging.
Since then, I have been flying ( hover, sport flying ) in warmer temperature, 30-35C without getting into auto reset.
Could there be more than the SD card causing the problem?

[rceccleston]

Originally Posted by desertstalker

The SK720 is also limited to 2GB FAT formatted, it cannot save files to any other type of filesystem.

Sounds like the file system is limited to FAT16 which has a limit of 2GB, more than enough for hundreds of flight logs.

Would be nice if Castle's ESC's internal memory could be expanded to hold more than a few flight logs.