AV-Sync for Podcatcher Classic

With AV-Sync, Podcatcher Classic plays audio in sync with a video on a screen. Any number of visitors can watch the same video and each hear the audio in their own language.

Note

This page is for Podcatcher Classic. Podcatcher Pro uses a different AV-Sync setup — see Understanding AV-Sync.

How it works

The media player plays the video on the screen. Instead of the normal sound, it sends an AV-Sync track to the AV-Sync box. The box combines that track with an IDentifier code and sends both out as infrared through the AV-Sync IDentifier, which is connected to the box by cable.

When a visitor points a Podcatcher Classic at the AV-Sync IDentifier, the device reads:

• the IDentifier code — which audio to play;
• the AV-Sync signal — how far the video has progressed.

It then plays its stored audio from that point. One signal is enough to stay in sync for the whole video; the visitor does not need to keep pointing.

What you need

In the AV-Sync set

Item	Purpose
AV-Sync IDentifier	The point visitors aim the Podcatcher Classic at.
AV-Sync box	Feeds the AV-Sync IDentifier the right signal.
5V power adapter (narrow plug)	Powers the AV-Sync box.
Audio cable (3.5 mm jack → 2 × RCA)	Connects the media player to the AV-Sync box.
RCA cable	Connects the AV-Sync box to the AV-Sync IDentifier.

Long range IDentifier

Some installations use a long range IDentifier for remote activation, so visitors do not need to aim at a nearby AV-Sync IDentifier. It may still be in use at your site, but Guide-ID no longer sells it. A long range IDentifier needs its own 9V adapter — not the 5V adapter of the AV-Sync box — and shows a light on the back when it has power. If you have more than one in a room, they can disturb each other: contact the helpdesk.

Not included

• Screen or projector for your video.
• Media player with an audio-out connector that can loop the video if needed. Guide-ID recommends a BrightSign media player.
• Video with the AV-Sync track, and the audio as MP3 for the Podcatcher Classic. You make both with the AV-Sync Video Tool — see AV-Sync media preparation.

The AV-Sync box

Part	Function
ADDRESS DIP switches	Set the IDentifier code the box transmits, or flexible mode.
Error LED (red)	Blinks: the signal from the media player is not a valid AV-Sync track. Steady: no signal at all.
OK LED (green)	Blinks when a valid AV-Sync track comes in.
ON LED (yellow)	Steady when the box has power.
GAIN knob	Amplifies the incoming signal (clockwise = more). Keep it as low as possible.
AUDIO IN	Connect the red RCA plug of the audio cable. The white one can stay unconnected — the box needs mono audio only.
IR OUT	Connect the AV-Sync IDentifier with the RCA cable.
5V DC	Connect the 5V power adapter.

Specsheet AV-Sync (PDF)

Using a Brainbox instead of the AV-Sync box

You can also use a Brainbox, the AV-Sync controller of Podcatcher Pro. It works with Podcatcher Classic as well. Connect the audio output of the media player to the 3.5 mm audio input of the Brainbox, and connect the AV-Sync IDentifier to the RCA infrared output of the Brainbox. For installing the Brainbox itself, see the Brainbox User Manual.

Step 1 — Prepare your media

Run your video through the AV-Sync Video Tool. It creates a video file for the media player and an audio file for the Platform. See AV-Sync media preparation.

Step 2 — Choose a code and mode

The AV-Sync box works in one of two modes:

Mode	Code range	How the code is set
Regular	A0:01 to A0:7F	Fixed on the box with the DIP switches. One video per box.
Flexible	A1:00 to A1:FF	Carried in the AV-Sync track of the video. Lets one box play different videos. You choose the code in the AV-Sync Video Tool.

Specsheet AV-Sync DIP-switch settings — all codes (PDF)

Step 3 — Configure the Stop in the Platform

1. Log in to the Platform and open the tour in the Tour Editor.
2. Add a Stop and choose Audiovisual Sync Tour Stop.
3. Upload the audio file the tool created (the file ending in _audio). For more languages, upload a separate audio file per language. Every language file must be exactly as long as the original.
4. Open Stop settings and enter the code under Video Code, for example A001 (regular) or A101 (flexible).
5. If the video loops on the media player, make the clip loop on the Podcatcher Classic too: turn on Automatically replay this clip when it is finished.
6. Leave AV-Sync Offset at Not set unless you need it — see Fine-tuning.
7. Publish the tour and sync your Podcatcher Classic devices so the content reaches their SD card.

Step 4 — Install the hardware

1. Screen — connect the media player to the screen or projector, usually with HDMI. Follow the media player’s instructions.
2. Audio — plug the 3.5 mm jack of the audio cable into the media player’s audio out. Connect the red RCA plug (right channel) to AUDIO IN on the AV-Sync box.
3. Room sound (optional) — want sound from the screen as well? Connect the white RCA plug to the screen or amplifier. This requires a video prepared with room audio.
4. DIP switches — set the code on the box (see below), then restart the box by briefly disconnecting and reconnecting the power.
5. AV-Sync IDentifier — connect it to IR OUT with the RCA cable. You can extend the RCA cable if needed.
6. Power — connect the 5V adapter to 5V DC and plug it into a power outlet (100–240V AC, 50–60 Hz).
7. Placement — put the AV-Sync IDentifier close to the screen so visitors know where to point. Hide the box and cables from view, but keep them reachable.

Caution

Do not extend the audio cable between the media player and the AV-Sync box. The signal degrades and the box may no longer decode it.

Setting the DIP switches

• Regular mode — set the ADDRESS switches to the binary value of the last digits of the code. For A0:01, only the leftmost switch is up. For A0:02, only the second switch from the left is up. Look up any other code in the DIP-switch specsheet.
• Flexible mode — set all ADDRESS switches up. The box then takes the code from the video.

After changing the switches, always restart the box by disconnecting and reconnecting the power.

Step 5 — Test

1. Video — start the video and check it shows on the screen. Make sure the media player is not muted and not too quiet.
2. Gain — turn the GAIN knob fully counter-clockwise, then slowly clockwise until the green LED starts blinking.
3. Audio — point a Podcatcher Classic that has a tour started at the AV-Sync IDentifier. Wait for the beep and check that you hear the video’s audio.

If the Podcatcher Classic does not play, check that the green LED blinks regularly. If it does not, swap the red and white RCA plugs at the AV-Sync box and try again. Still nothing? Check the code and the sync status in the Platform.

To read the code the box is sending, see Read the code when you cannot see the back.

Using AV-Sync

Visitors point their Podcatcher Classic at the AV-Sync IDentifier, just like at any other IDentifier. They hear the audio in their own language, in sync with the video, however far the video has progressed.

Fine-tuning

Offset correction

The audio on the Podcatcher Classic is lip-sync with the video as long as the original sound would also be in sync in the same setup. That is not always the case — for example when a 4K television delays the picture while the audio comes straight from the media player. Avoid this where you can by taking the audio from the screen’s audio output.

If that is not possible:

1. Measure the difference between audio and video, by ear or with AV-Sync Test Mode (below).
2. In the Tour Editor, set AV-Sync Offset on the clip. It ranges from −200 to 200 ms in steps of 10 ms.

Loop correction

If the media player and the Podcatcher Classic both restart the video automatically, they can drift apart: the Podcatcher Classic usually restarts the audio faster than the media player restarts the video. Correct this by adding silence to the end of the audio with the Extend option in the AV-Sync Video Tool.

AV-Sync Test Mode

AV-Sync Test Mode helps you find the right offset. You do not need it if audio and video are already in sync.

1. Hold the middle (B) and right (C) buttons while you take the Podcatcher Classic out of the Dockingstation. You are in AV-Sync Test Mode when the yellow LED blinks together with the green LED as a tour starts.
2. Aim the Podcatcher Classic at the AV-Sync IDentifier.
3. Press the left or right button to decrease or increase the offset. The Podcatcher Classic speaks the value after each press; a minus is spoken as “Foxtrot”. The middle button resets it to 0.
4. Aim at the AV-Sync IDentifier again. The audio now plays with the new offset; the red LED shows an offset is active.
5. Repeat until you are happy with the sync.
6. Press the middle button while audio plays to hear the last value used. Enter that value as AV-Sync Offset for the clip.

Troubleshooting

Check the basics first

• Is the audio cable firmly connected to the media player and the AV-Sync box?
• Is the RCA cable firmly connected to the AV-Sync box and the AV-Sync IDentifier?
• Are the media player and the AV-Sync box both powered?
• Does the video have the AV-Sync track on the right audio channel?
• Is the same code set on the AV-Sync box and in the Platform?
• Was a tour started on the Podcatcher Classic with a Start IDentifier?
• Has the Podcatcher Classic been synced with the latest content?

Still not working? Unplug the 5V adapter, wait about half a minute and plug it back in. Restarting the media player can also help.

By symptom

Symptom	What to do
Yellow LED is off	The adapter is not in a working outlet, its cable is not connected to the box, or the adapter is broken. Use another outlet or replace the adapter.
Green LED blinks, but the Podcatcher Classic does not respond	Check the RCA cable at the AV-Sync IDentifier; squeeze the connector slightly for better contact. Start a tour with a Start IDentifier and try again, or try another Podcatcher Classic. Sync the Podcatcher Classic and try again.
Red LED blinks	The box gets a signal, but no valid time code. Lower the media player volume by 20%, restart the box, reconnect the audio cable and turn the GAIN knob until the green LED lights up. Listen to the media player output with headphones: you should hear regular beeps. No beeps means the video has no AV-Sync track or the audio output is not selected. If the track is on the left channel, swap the red and white plugs.
Audio always starts from the beginning of the video	The Stop is not an AV-Sync Stop. Check that it was added as Audiovisual Sync Tour Stop, publish and try again.

Troubleshooter

Still unsure where the problem is? Work through the AV-Sync Classic Troubleshooter step by step.

Still stuck? Email helpdesk@guide-id.com.

Related articles

• AV-Sync media preparation (Classic) — make the video and audio files
• IDentifiers for Podcatcher Classic — types of IDentifier, including the AV-Sync IDentifier
• Installing IDentifiers — placement and reading the code
• Synchronizing Podcatcher Classic — get the audio onto the devices
• Troubleshooting Podcatcher Classic — common problems and solutions
• Brainbox User Manual — install the Brainbox, also usable for Podcatcher Classic