Yamaha vss-30 HELP NEEDED

electroclone · December 17, 2010, 02:12:02 PM

Hi.Greetings from a newbie.Just purchased a VSS-30,but both the sampling and overwrite functions are faulty.The sample button clicks,but does not record anything and then freezes.I have to turn on the power again to get at the keyboard sounds.Any help would be highly appreciated.All the best.

jamiewoody · December 17, 2010, 07:44:27 PM

there are others here much better than i am at troubleshooting.

have you taken it apart yet? if not, i would take it apart, and look at the obvious first. if using batteries, check those first. it may be the sampler uses more current than the rest of the unit.

look closely at all printed traces on the board. especially around the sampler part of the circuit. check the microphone. is there a plug in for an external mic or unit? try those.

electoyd · December 21, 2010, 02:34:05 PM

maybe use a multi meter and see if there is any life in the sample chip, i take it you have opened it up? Did you get this from ebay? Just wondering if maybe you have inherited someones else's experiment gone wrong, i've damaged the sample chip on 2 vss200 but that was when i didn't know what i was doing, they basically worked but there was no sample option and it could be the case with the one you've bought if it looks like someone has had a go at this i would try and get your money back, esp if you have paid alot for it. Without the sampling option they are not really worthwhile.

Maybe you could get a new sample chip if you could find out what chip it is or if there is an equivalent, maybe gordon jcp (member of this forum) could help with that. Alternatively try and get a hold of the service manual, maybe that would be listed in it as a problem, i'm sure i have the service manual for the vss200 but i dont know how much use that would be, but they both have pretty much the same sampling ability. It does sound like the sample chip is goosed though.

electroclone · December 21, 2010, 11:45:13 PM

First of all many thanks Jamie and Electoyd for getting back to me.I bought the VSS off an auction here in Japan .I think there is a problem with the input signal,but will certainly look into the sample chip.

Circuitbenders · December 22, 2010, 03:24:40 PM

It could be that the input socket or the mic is broken. I think when you press sample it waits for a signal over a certain threshold and then starts sampling. If it never receives a signal it could conceivably just wait forever and appear to have locked up.

Have you tried sampling from the line in and from the mic? If the sample source automatically switches to line in using a switching jack when you plug in an external source, it could just be that the jack socket is damaged and its not switching back to mic or getting a signal from the line input.

Step one with fault finding is to suspect the mechanical stuff first. An error that i make time and time again.

electoyd · December 22, 2010, 04:34:56 PM

yeah thats a good call from Paul, i had presumed you had tried the sampling from both options, but yeah it could be a broken switching jack now i think about it-i had a look in the service manual for the vss200 last night but couldn't really see anything that would relate to the vss30 though they probably use the same chip. Maybe even check the soldering on the mic/jack make sure there isn't a dry joint or anything. Good luck man sure that was a few bucks if you got it from Japan. I wrecked a vss30 a few years back (not sampling chip as far as i know) i may still have the main circuit board lying about in my attic (which is where alot of misc/broken stuff ends up) If this turns out to be the chip and not the jack, i will see if i can find the circuit board and maybe i could send it to you and you could take some bits off it if we can find out whats wrong. This is a big if, because i cant guarantee i still have the"broken" board, so if you try and find out what is wrong via what we have said we may be able to help.

natere2ster · December 23, 2010, 01:34:51 PM

I would try and find the service notes and schemos and start "working down the line"

Usually you test power rails first, make sure they are in spec.

If that looks good I would recommend reseting ICs and maybe cleaning?

Hard to tell but I have gotten away with a lot of repairs for glitchy behavior of older instruments....

Hope this helps, sort of generic and aplies to most electronic music instruments (to an extent anyway)

Cheers,

Nate

backsliders · May 24, 2016, 04:12:05 PM

I know this is a dead topic, but I wanted to post an answer for anyone who is suffering from this same issue.

It's the DRAM. I had the EXACT same issue and while it was difficult to remove the IC chip, I replaced it with another MB81256-12 I got off Ebay and voila! Working like a charm now! Good luck, guys!

Telkmx · June 11, 2016, 12:38:04 PM

Oh man thanks just seen this.
http://www.ebay.ch/itm/3x-MB81256-12-D-Ram-256K-120ns-DIP16-FUJI-Lager-G090-/171754028585?hash=item27fd567e29:g:~7UAAOSwpDdVLNFN
IS this it ?
I'll order it and try myself.

Vanx · January 27, 2020, 08:55:10 AM

Hello, sorry for re-upping this thread!

I've got a VSS30 and it seems fully working... I suspected the RAM chip, but for example "recording and playback" (of performance) works, and sampling works... but! It has an high volume sampling threshold, I need to shout really near the grille, and it wants high volume also using the RCA input. Even when shouting, is not easy to even make it record the sample full length.

Who had the same issues? Could still be the ram chip? I first excluded this because it can actually store informations on that chip, but this high threshold seems strange because is bot for internal microphone and RCA input.

Thanks in advance!