This i great news skydragon.

Now i'm awaiting for the connectors to come in. Then i can modify my GoPro's too..

Quick comment regarding the connectors.

I bought some bare ipod-type connectors here in UK and found that although they do fit, they are a very tight fit. Ie. The insertion force is very high.

The connectors are these. http://www.coolcomponents.co.uk/catalog ... ucts_id=48

If i compare it to say my ipad where the connector just gently clicks into place, the connecotors i used require a strong insertion force.

They do connect and work ok, and electrically they seem fine. The strong insertion force in some ways is a good thing, as it makes sure the connector stays securely in place, when connected to gopro.

I also tried pluging an apple ipod connector into the gopro but couldn't get it to fit. It seems that the metal 'latches' on the side are different.

I omitted to fit the metal pin/latches on the connectors i used, when i assembled them (look at photo in link above and you will see the two loose metal pins) to avoid any such problems.

I omitted

After some further research....

These comments might only apply to my specific goprohd

Looking at the gopro hd hero bus connector on my camera, although the central 'tongue' of the connector (the plastic part containing the pins) is exactly the same as an ipod connector, the metal frame around the connector recess is not.

Looking closely at the metal frame it has a metal lug in each corner, which serves as a mechanical guide for when the external connector is inserted into the gopro. On an ipod these two lugs are exactly symetrical and equal in size. On my gopro hd camera these lugs are of different sizes. This is what is stpping me inserting a standard apple ipod connector, because the metal frame on the male connector fouls on the metal frame of the gopro's connector. When i have used the connector i bought from the link above (btw i believe this is a sparkfun connector) because it has no metal frame and because it is plastic body only, the metal frame on the gopro has cut away part of the plastic connector' body. We are only talking approx 1mm difference.

The cut/damage to the connector is minimal and once done is ok. This is what caused the high insertion force initially and the very snug fit now. (might actually be a positive thing in real world usage).

This makes me think

A) perhaps this is engineered by gopro intentionally like this and they will use a spefific custom made connector.

B) perhaps this is an engineering/production error by gopro and an apple ipod connector should fit perfectly.

C) perhaps my specific camera is incorrectly made.


I'd be interested to hear from anyone who can (gently) try insertly an (unlugged) apple ipod connector in their gopro, whilst the gopro is turned off, to see if this issue is just with my specific camera, or a wider issue as per (B) above.

I would go with A, my connector also required modification to fit the GoPro.

Good job skydragon! I wonder if is possible to record and play stereo audio (R and L channels) as well.

Regarding the connector, please look at this: http://www.jae-connector.com/en/pdf/MB-0111-5E_DD1.pdf. This seems to be the proper plug (asymmetric): DD1P030MA1, but is probably not easy to obtain (at least not as easy as iPod plugs). Looks like GoPro made this connector intentionally a bit different than Apple's famous one. Anyway, in my case, I just bent the bigger lug by long-nose pliers out of the way and that solved the tight fit problem (and still remains compatible with original GoPro extensions).

Seems it's pretty easy to purchase:
http://parts.digikey.com/1/parts-ts/index355.html

German source:
http://de.mouser.com/ProductDetail/JAE- ... 16LRQS1w==

Google search for DD1P030MA1:
http://www.google.com/search?client=ubu ... 8&oe=utf-8

So, whom orders one to give it a try?

Jan

Thanks GoProit, great info. That explains the difference in connector type from a standard Apple ipod connector.

I've just ordered a couple from http://uk.rs-online.com/web/search/sear ... &R=0435699

I tried some more tests with the audio at the weekend. I tried feeding in a electret 'tie-clip' type microphone straight into the GoPro's audio input and although it recorded, the audio level was very (too) low, confirming that the GoPro's audio input requires a line level signal rather than mic level.

So...I'm going to rig up a very simple amplifier circuit to give the microphone 25db of gain, which should do the trick nicely.

Regarding stereo audio. I'm sure the left and right inputs used correctly would give stereo input, but I'm just using audio in R for now as a mono source.

Jan,

I might try to order one straight away, I need a few other parts from Mouser but I can probably shift them to Digikey if I can meet the minimum order amount. Need to find the other connector so I can make an extension cable that can also have test points... Just bought the LCD bacpack so I'm hoping it will unlock a few of the last remaining secrets. Looks like this is the number for the mating connector DD1R030HA1R1300

Also BlueCore company has some new Bluetooth boards coming out (if you can find them), one of them has a video encoder board built in that coupled with what we know about the expansion connector would let us make a BT video connection to devices that support video over BT. Just something to think about for the future.

New firmware to go with the LCD, some things that we knew could be different now:
http://gopro.com/support/hd-hero-firmware-update/

I upgraded my GoPro to latest FW (v 1.01.46) and it still works ok with hero bus as per my last posts.

fwiw - I added a simple preamp circuit to my microphone, giving approx 25dB gain. The mic now works well with the GoPro's audio input. Quality isn't hi-fi but it is acceptable for my purposes.