Frequently Asked Question Posted 05/07/2010

What cables do I need to sync timecode between cameras and MovieSlate?

With the in-app purchase of MovieSlate's optional "Timecode Sync PRO" module, your MovieSlate can accept LTC timecode from external audio sources, or you can use MovieSlate as a timecode generator.

MovieSlate supports these LTC frame rates: 24, 25, 29.97, 30.

Use compatible devices

You’ll need an external timecode device (camera, timecode generator, or audio recorder) that’s capable of sending and/or receiving LTC timecode over an audio cable.  Not all sound sources have this LTC feature, but often professional-level gear does.  If in doubt, check your device’s owners manual for LTC-IN and LTC-OUT ports.

Enable the “PRO Sync Module”

To sync MovieSlate’s timecode with external sound sources, you’ll need to enable the MovieSlate 2.0 “Sync from Camera” PRO module (a $49.95 in-app purchase).  To do that, run MovieSlate, tap the Settings tab, select the “Timecode Syncing” item, tap the “PRO Sync Module” item’s ENABLE button.  On the next screen, tap another ENABLE button to confirm, then follow the on-screen instructions.

But please read the next paragraph first...

Try Before You Buy

Before purchasing the PRO module, you should test your sound source and cables with MovieSlate.  Starting with MovieSlate version 2.2, there’s a test screen dedicated to this purpose.  The test screen displays audio input level information, and displays the timecode as it is decoded from the incoming LTC signal.

Run MovieSlate, tap Settings tab, select the “Timecode Syncing” item, and tap the “Test Headphone Connection” item.  The test screen appears.

Plug one end of your cable into the external sound source, and the other end into your Apple iOS device (iPad, iPhone, or iPod touch).  Start generating timecode from your sound source.  If your cabling is correct, then you should see some volume levels appear in MovieSlate’s test screen.  If the levels are green, then you should start seeing timecode displayed on the test screen.

If the levels are not green or timecode does not appear, then you’ll need to do some troubleshooting.  Read on...

Troubleshooting Cables

When sending timecode from MovieSlate, use a standard, unattenuated cable.

When receiving timecode in MovieSlate, use a custom, attenuated cable as described below.  There are three variables to take into account for the receiving cable:

  1. Headphone jack (on the Apple iOS device end of the cable) - this jack must be one with four distinct silver bands (as pictured above).  Without those four bands, an iPad/iPhone/iPod touch won't be able to accept audio input.

  2. Jack at other end of the cable - must fit the sound source (such as your TC generator or sound recorder).  Your sound source’s manual is a good place to find the type of plug required.  Failing that, you could Google for that information.

  3. Attenuation - is actually a way to decrease the volume of the audio that the Apple iOS device receives.  Depending upon your sound source, you may not need any attenuation.  However, most pro-level sound equipment outputs at LINE level (very loud).  All Apple iOS devices receive audio at MIC level (very quiet).  If your sound source outputs LINE level audio, then it will easily overpower the poor Apple iOS device.  So the audio must be attenuated (quieted).

Attenuation may require a bit of trial and error.  Not all sound sources (cameras, TC generators, and sound recorders) output audio at the same volume levels.  If your sound source has an output volume control, then it is easy to test using MovieSlate’s test screen (see “Try Before You Buy” above).  While viewing MovieSlate’s test screen, simply adjust the soure source’s volume until the test screen levels are green and timecode appears in the test screen.

Some sound sources don't have a way to control their output volume.  In these cases, if you find that the volume is too high for the Apple iOS device, then you'll need to also purchase an attenuating cable-- such as the ones described below.

Sources for Required Cables

You’ll need cables running from your camera or TC generator to the iPad/iPhone/iPod headphone jack.

The iPad/iPhone/iPod end of the cable must be a four connection mini jack (four visible bands; just like the jack used on Apple's iPhone headphones).

The audio signal needs to be at MIC level-- not LINE level which would overpower an iPad/iPhone/iPod headphone jack input.  Many cameras output their audio signal at MIC level already.

If your camera’s LTC audio output is at LINE level or is too loud, you will have to attenuate the audio signal.  For instance, we've been testing with external Horita timecode generators that export audio at LINE level, and so we've been using this set of cables:

iPhone Adapter 3.5mm 4 conductor TRRS Male to 1/4in Microphone Input Jack with built-in -22db Attenuator
http://www.kvconnection.com/product-p/km-iphone-mic42-a22.htm

RCA female Jack to 1/4 Mono Phone Plug
http://www.kvconnection.com/product-p/d-ad170-6.htm

RCA male to RCA male cable.
http://www.kvconnection.com/product-p/t-p-p-3.htm

This discussion on Apple's boards reveals the pinouts:
http://discussions.apple.com/message.jspa?messageID=5262651

BNC to iOS Device Timecode cable.
This cable is designed specifically for use with MovieSlate.
http://www.kvconnection.com/product-p/km-iphone-bnc-a22.htm

BNC-to-RCA adapters. We don't have access to equipment with BNC connections to test with, however we believe that a simple BNC-to-RCA adapter will work without problems (provided you get the signal level right, of course). If you have had success with these adapters we'd appreciate a quick note letting us know!

BNC Female to RCA Male adapter.
http://www.kvconnection.com/product-p/d-ad140-17-bncf-rcam.htm

BNC Male to RCA Female adapter.
http://www.kvconnection.com/product-p/d-ad170-5-1.htm

If your equipment uses XLR connectors:
http://www.kvconnection.com/product-p/km-iphone-micx-a22.htm

Folks looking to integrate the TC over Sennheiser wireless mic receiver:
http://www.kvconnection.com/product-p/km-iphone-mic-sen.htm

Folks with RCA-style LINE OUT on their gear:
http://www.kvconnection.com/product-p/km-iphone-micp-a22.htm

If your gear is outputting MIC level signal you can use one of KVConnection's MIC adapters
without the built-in attenuator:
http://www.kvconnection.com/iPhone-Adapters-s/8388.htm

Folks in the UK should check with MLEC (UK) Ltd.  They've custom built cables for other MovieSlate users-- including those using Sound Devices recorders.

LEMO. Sigh. We don't have any equipment that uses LEMO connections right now so we can't guide you to any tested solutions, and we don't have many leads on LEMO adapters. Here's what we've dug up so far, depending on your variant of LEMO:

3-pin LEMO to XLR Adapter: (LEMO to XLR, then use one of the XLR adapters above)
http://www.fullcompass.com/product/284060.html

5-pin LEMO to 3p XLR M/F adapter:
http://www.canford.co.uk/Products/79-2252_SOUND-DEVICES-XL-LX-TIMECODE-CABLE-Lemo-5-pin-to-1x-XLR-3M-1x-XLR-3F-610mm355mm

Mouser Electronics is an authorized distributor of LEMO products:
http://www.mouser.com/lemo/?utm_source=google&utm_medium=ppc&utm_campaign=connectors&gclid=CIfcvNeUraQCFRD_iAodORAncg

Remote Audio has a few TRRS to XLR, LEMO, and BNC adapters, we haven't used any of these but they look pretty slick:
http://www.remoteaudio.com/cables_adapters/idevice/

Location Sound may be able to assist with adapter chains:
http://www.locationsound.com

And finally, the source:
http://www.lemo.com

A Wireless Solution

Many folks have had success sending timecode audio to/from MovieSlate wirelessly using transmitters and receivers like those from Comtek.

A common workflow is to cable-connect the LTC output from a sound recorder to a wireless transmitter.  Then cable-connect a wireless receiver to the iOS device(s) running MovieSlate.

Trew Audio often has good deals on used Comtek gear.