Audio Issue with Retrospectives AV Board

[daskrabs]

http://www.aliexpress.com/store/product/AV-Module-for-your-8-Bit-system/138988_32287368288.html

Anyone buy this? Video quality looks good, but I'm having issues with games with expansion audio, specifically Gimmick (legit cart). Audio is very distorted. Tried Contra as well, audio seems ok. Anyone else having audio issues with any games?

[chowder]

Yes, I've ordered a couple of those boards now.  I've donated one to a friend, so I can't check, but I don't remember having any issues with expansion sound games.

I've got another Famicom on the way from Japan, so I'll fit it when it arrives and check it out with those specific games.

[P]

I would check pin 45 and 46 on the cartridge connector. Also if you have FDS or any other expansion audio games to try, see if the same problem happens on them too so you know it's not a problem with Gimmick!

[Retrospectives]

I sincerely apologize for the late reply. Like P said, please check pin 45 and 46 on the connector.
We make sure that all our boards are working correctly before shipment (we don't get a million of orders so we clearly make sure that everything works), but of course there is a possibility that the "human factor" has played a role.

Can you please try to record the distortion or do you got a multimeter or any other tools? Please let us know and we will of course refund/exchange any faulty items for you.

[daskrabs]

I removed the AV board and reinstalled the RF board, and the issue went away. I'll retest with more carts tonight or tomorrow. If I had to guess, I'd bet a resistor somewhere has the wrong value or got switched.
Post Merge: August 07, 2015, 06:54:39 pm
I retested the board with Gimmick, SMB, SMB3, Contra, Akumajou Densetsu, Zelda (FDS), and Bio Miracle (FDS). Gimmick is the only cart with bad audio. Can someone with this board and a legit Gimmick please try to reproduce my findings?

[Great Hierophant]

I removed the AV board and reinstalled the RF board, and the issue went away. I'll retest with more carts tonight or tomorrow. If I had to guess, I'd bet a resistor somewhere has the wrong value or got switched.
Post Merge: August 07, 2015, 06:54:39 pm
I retested the board with Gimmick, SMB, SMB3, Contra, Akumajou Densetsu, Zelda (FDS), and Bio Miracle (FDS). Gimmick is the only cart with bad audio. Can someone with this board and a legit Gimmick please try to reproduce my findings?

Does your Gimmick! cart sound good on another system?  Dirty pin perhaps?

[daskrabs]

Its very clean. Works fine on unmodded Famicom and AV Famicom.

[daskrabs]

Just noticed that there's a .01uF cap missing from the board. It's shown on the AE sample image. I'll add it to the board and retest this weekend.

[chowder]

Just noticed that there's a .01uF cap missing from the board. It's shown on the AE sample image. I'll add it to the board and retest this weekend.

Sounds like you've cracked it, that cap is present on my AV board.  Is it the one near the LED or towards the corner of the board?  The Famicom's arrived, so I'll install it this weekend and give it a test.

[Algo Fonix]

I've got one of those boards on the way and was wondering if either of you could post some pics of the video quality you get out of em.

[daskrabs]

Well, turns out replacing the capacitor solved nothing. Here's a video of the issue:

https://www.youtube.com/watch?v=5HhNJeqrJNg

I think I need a refund. It's such a shame that it plays everything else.