Arri Alexa 35 Won’t Accept Denecke JB-1

[George]

Not sure if anyone else experienced this but I just started a show with the Alexa 35. After 2 days, they will no longer accept timecode from the JB1 sync boxes.  Switched out cables, different boxes, switched between the two cameras, changed output levels on boxes. Nothing is working. They will take the time code but eventually give an error code. However, the cameras do take Ambient sync boxes. Would love to solve this as I’m sure there is something we aren’t thinking of.

 

Thanks,

 

George

[Philip Perkins]

So for the first 2 days the JBs worked ok?   If so that sounds like a camera issue.  Did they sneak in a firmware update on you?

[George]

Hi Philip, That was the first thing I asked. They said they didn’t. The last firmware update from Arri was back in Oct. Hopefully, a new firmware update will remedy the situation. Until then, we’re staying with the Ambient. Thanks

[Axel Mishael]

Any input follow up on the deneckes with the Alexas?

 

 

Axel.

[Philip Perkins]

Are other brands of TC boxes working ok with this camera?

 

[George]

Denecke’ s still don’t work with the current firmware on the Arri 35. I’m still using Ambient. Our utility had Ultrasync One’s. They worked as well. I talked to Denecke and there is no other incidence of this. The plus side is I really like the Ambient Nanolockit.

 

 

[Philip Perkins]

I wonder if Denecke would send you a new loaner to try?

[johngooch]

From time to time i end up using tentacles as last ditch effort with some Alexa minis when JB-1 do not work..   do not know why but it has happened several times.   

[John Blankenship]

Some of the early JB-1s had an issue with a wrong component installed. Denecke fixed mine at no charge.

 

The issue I had that led me onto this was that the voltage output would slowly diminish on one of my units (I compared two units with a VOM at different voltages). 

 

[referencetone]

Just ran into this problem today. Alexa 35 accepted timecode from my Betso box yesterday, but today it apparently took several tries before it accepted it.

 

”Connected time code signal cannot be used for time code tuning. (#90)” 

[Patrick Tresch]

Isn't it related to the level output of the box?

I had this problem on a camera, at the end it was solved changing the level output setting of the TC box.

[Philip Perkins]

19 hours ago, Patrick Tresch said:

Isn't it related to the level output of the box?

I had this problem on a camera, at the end it was solved changing the level output setting of the TC box.

More or less level?  I've had it go either way....

[JonathanReye]

I've also ran into this problem at work. I own 4 JB-1s and 2 out of the 4 can jam cameras A & B. The other two causes Camera A & B errors, but for some reason one of them that can't jam camera A & B can Jam camera C. Very confused... Guess I'll call Denecke on Monday.

[George]

I called Denecke at the very first incidence of this they said it was on the camera end. About a month later I called again asking if they had anybody else contact them regarding the Arri 35 issue. They said they had not. The show just ended. I do hope to resolve this at a local camera department. I did change output volume, I tried a brand new JB-1 with new cable. It still didn’t take it without an eventual error code. So, I’m sticking with the Ambient. I’ll still use the JB-1 with other cameras. With (4) JB-1’s and assorted cables, it’s too much of a commitment to switch at this point

[Phillip C Dent]

I worked with the Arri 35 yesterday. I did not have any timecode or audio level issues. My Denecke JB-1 jammed the camera immediately. I disconnected and re-jammed multiple times to see if I could cause an issue.  The 35 took the time code every time.  
 

I had also read somewhere that this camera would change audio input levels when power cycled. I was paranoid the entire day, so at every battery swap I checked the settings on the Sonosax AEM. I had the camera set to aes input and I had no issues the entire day.

[Wandering Ear]

On 3/7/2023 at 6:47 PM, referencetone said:

Connected time code signal cannot be used for time code tuning. (#90)” 

Does this happen in Jam-Sync or Regen?  Or both?  That error sounds like an issue tuning the internal clock in jam-sync mode, but I haven’t come across it so i was just curious. 
 

One reason i ask is the following note from the Arri manual:

 

“Note: Due to the tuning mechanism, jamming the camera might take up to
30 seconds and a timeout is issued if tuning could not be completed after 60 seconds.”

[OB1]

Happened this week on this cam. First the SB4 wouldn't take so moved to a SyncE. It took about a minute for the TC to stop flashing on the Alexa but it finally took it.

Maybe it does have something to do with the timeout spec?

 

[Ontariosound]

Are the JB1's updated to V 1.7 software ?

[Toddsound]

Is the TC Cable the same for the 35 as for an Alexa Mini? I am about to work with this camera for the 1st time

this week.

[Phillip C Dent]

On 5/20/2023 at 11:11 AM, Toddsound said:

Is the TC Cable the same for the 35 as for an Alexa Mini? I am about to work with this camera for the 1st time

this week.

Yes

[osa]

i am considering purchasing a set of these nanolockits - has anyone come across a lemo to bnc adapter without cable involved, like an all in one metal adapter?

[KenLac]

The problem of getting my JB-1s to play nice with Arris (of any model) has been bedeviling me for a couple of years now, and I’ve never had time in the field to try to sort it all out. Thanks to the good people at Talamas Broadcast in Boston, this week I was finally able to sit down with a couple of Arris and do a focused deep-dive into the problem. Together we made some very helpful discoveries.

 

SHORT STORY (based on my experiences with my JB-1s…)
* Arris will always pick up the right timecode numbers, but will frequently give additional error messages
* Arris have three different menu settings that interact with timecode input (and Arri’s documentation is quite confusing.)
* Only one of these settings is responsible for the error messages
* That setting is a configuration you’d probably never want to use with a JB-1 anyway.

 

IMMEDIATE SOLUTION: Make sure “Timecode Mode” is set for REGEN and not JAM SYNC.

 

SLIGHTLY LONGER STORY:
The three different features that interact with timecode are:

• “TIMECODE RUN MODE”  [HOME > TC > OPTIONS > RUN MODE]
• “TIMECODE MODE”  [HOME > TC > OPTIONS > MODE]
• “SYNCHRONIZATION” [SYSTEM > SENSOR > GENLOCK SYNC]

We can disregard RUN MODE as a cause of the problem because we’d never use REC run with a JB-1, only FREE.

 

That leaves four combinations of the other settings, and one of them is prohibited by the camera. See attachment below for chart.

 

 

 

As you can see, there’s only one mode that leads to error alerts, and that’s when having TIMECODE MODE set to JAM SYNC.

 

According to Arri’s convoluted documentation, they recommend this mode only if you were jamming timecode into the camera and then removing the timecode source. Obviously we’d almost never use a JB-1 in that fashion: the point of something like a JB-1 is to  keep it connected to the camera all the time. Arri recommends REGEN when you’re keeping the timecode source connected, so in almost all JB-1 situations we can simply avoid the configuration that gives errors.

 

Note that even in the problematic configuration, the camera will pick up the right numbers! The failure will be only in that the internal timecode circuitry in the camera gives up on synchronizing to the external source — something it doesn’t actually need to do as long as we keep the JB-1 connected.

THE REST OF THE STORY:

I suspect what might have happened to George (the original poster) is that one day the camera accidentally got changed from REGEN to JAM SYNC.

 

Having Genlock Sync in TIMECODE mode will sync the image sensor to the incoming timecode. However, it has no affect on the errors from a JB-1. And how it differs operationally from syncing just the timecode reader I don’t understand.

 

Because we’re curious types, we eventually started running some various TC devices into a scope, and that revealed the level out of the JB-1s was much lower compared to some other options. A multi-meter confirmed it. Then for yucks, we ran the JB-1 output into a mixer and kicked it up a good 10dB, and waddayaknow, the Arri eventually locked to it in Jam Sync mode. (Obviously this is not a useable solution in the field…)

 

I think a big part of what makes it confusing is Arri’s description of the various modes. When I see documentation that says, “The camera samples the timecode value and simultaneously tunes its internal timecode clock to match the clock of the timecode source,” is it really surprising someone would think, “Well, why wouldn’t I want that, it sound great!”

 

It also doesn’t help that Arri uses the term “regen” in a very different way than some other manufacturers. Terms like EXTERNAL and EXTERNAL-JAM would be a lot more intuitive.

 

I’m working up a white paper on our testing, and will share it here when it’s done. I gave Denecke and call and gave them a verbal debriefing. Might try to figure out how to hook up with Arri as well.

 

[Ridley]

KenLac provided a comprehensive analysis of the Alexa TC jam sync problem above.

 

I wanted to add that this problem also occurs on the smaller ARRI cameras like the Mini, using Betso TCX-2+ sync boxes. In my experience the typical workflow for these cameras is to work with the 1st AC to set initial settings at TOD to Free-run, Jam Sync. Throughout the day the ARRI timecode read-out will flash, which is accompanied by an error message. Have 1st AC go back into the settings menu, cycle from Rec Run to Free-Run, and Regen to Jam Sync.

 

Doing so usually fixes the issue and re-jams the camera. On rarer occasions I have swapped out the cable (BNC to 5-pin LEMO on the MINI) due to excessive heat concerns, since the cable sits right behind the main power supply of the camera. Doing this also seemed to have an effect on the time interval between TC errors.

 

Hope this helps.

[Izen Ears]

On 8/10/2023 at 11:34 PM, KenLac said:

Thanks to the good people at Talamas Broadcast in Boston, this week I was finally able to sit down with a couple of Arris and do a focused deep-dive into the problem. Together we made some very helpful discoveries.

 

Your efforts are greatly appreciated! I totally had this problem on my last show and it took the camera department a bunch of trial and error to figure it out. Thank you so much!

 

Talamas was the first place I bought any sound gear!  Good to hear they're still around.  Saw my first HD-TV there too, and that was really something. I remember looking between a window and the monitor and thinking how much more clear the HD was!

[osa]

Had my first issue with this today - mini 35 and a mini classic side by side. 2x jb1’s. Followed the very helpful instructions above to letter and no luck on the 35, but the older mini grabbed it right away no issues at all. 
 

just got a set of ambient nano-lockets but getting used to the blinkey lights and not knowing exactly what is happening without a screen is not the greatest under pressure. Once i checked my cheat sheet and got it going, nanolockit on mini 35 worked perfect. 1st n 2nd ac’s both found the note about a certain firmware i believe in the camera not working with the jb1, and the lower tc level output mentioned above could also be a factor. Nanolockits are good to have!