Help! Need a Casio MG 510 Service Manual

[krhnyc]

I know this is probably not the right place for this, but I have had no luck on the web. I have a Casio MG 510 that stopped working. When I took it apart I discovered that one of the caps (surface mount) had fallen off!  While handling it, 2 more fell off!!!    Ahhhhhh! I want to repair it, but I have no idea what the values are. I found a place that sells the service manual for $25, but I don't even know if this has the info I need... plus shouldn't information like that be available for free?

Please help,
Thanks- Kristopher Heels

[theehman]

... plus shouldn't information like that be available for free?

It should be free if the manufacturer is still in business and can provide it.  Otherwise, someone has used their own time to track down the documentation, scan it, make sure it's legible, and save it in a format for later use and preservation.  They should be paid for their time and for the web hosting they use to advertise that they have it available.  They also deserve their money from the fact that they saved you time (which, as we all know, is money) from looking everywhere for it.  Once you have the document, though, there's nothing that says you can't do the same or even pass it around for free.
Just my 2 cents from my past experiences.....

[krhnyc]

... plus shouldn't information like that be available for free?

It should be free if the manufacturer is still in business and can provide it.  Otherwise, someone has used their own time to track down the documentation, scan it, make sure it's legible, and save it in a format for later use and preservation.  They should be paid for their time and for the web hosting they use to advertise that they have it available.  They also deserve their money from the fact that they saved you time (which, as we all know, is money) from looking everywhere for it.  Once you have the document, though, there's nothing that says you can't do the same or even pass it around for free.
Just my 2 cents from my past experiences.....

Casio is no help. While I understand that there is some expense involved (research/web hosting etc.), $25 is a touch steep. Especially considering that I don't know that the info I need is contained therein. I was hoping a good Samaritan who does have the info I need would pass it along. I'm not trying to bilk anyone or put the website that sells this info out of business. My comment stems from the frustration that knowledge... which should be shared freely... has become a commodity, not just on the web, but everywhere. The rising tuition cost is a perfect example. It just seems unfair that people can be denied things like that based solely on whether they can afford it. Somewhat off topic I know.

[juse]

The caps fell off? Did they take the pcb pads with them? I'm surprised it worked at all....

[krhnyc]

The caps fell off? Did they take the pcb pads with them? I'm surprised it worked at all....

The pads are there. The caps (electrolytic) leaked and corroded their legs off. It worked fine, then it actually sorta worked... but you would really have to hammer on it to trigger.

[Ronsonic]

Casio has never been good at supplying service info - useless for out of production units - they are no help with this one. I have a manual on paper, repairing these is one of the things I do for a living - I'd have to charge as much for a copy as the other guy does. Sorry. If you google around you may find someone with the manual in an electronic format. Pretty much anything a technician needs to know to fix one of these is in the manual.

I am happy to tell you all about it for free 

First, there is nothing unique or rare about your problem. Cap fail is in the DNA of these things. I'll bet cash money that the ones falling out are 10u/16V - that is what they do, go bad and fall off the board. This leaves the pad corroded and terribly crudded up, but almost always cleanable. Surprising, but good news. I have gotten these in after someone attempted a repair who shouldn't be working with SMT. That's a problem and requires trace/pad rebuilding.

The first step in overhauling one of these is to replace those caps, all of them. If they aren't bad yet they will be soon. The other values seem to have fewer problems. I don't know why but they do. This is a real good time to have an ESR meter, or just replace all electrolytic SMT caps. TEST. OR. REPLACE. ALL. THE. CAPS. </shatner> Clean the board thoroughly between pulling the old cap and soldering the new one. Even if it didn't ooze its guts before, the heat of soldering will often cause it to release its yuck. Usually the caps are marked with the value, if not the voltage rating. Get used to the nasty fishy smell while you're working. SMT caps can now be had in smaller sizes than were available when this was built, measure and get the sizes before ordering.

Mostly that restores full function. Occasionally you'll find a blown opamp in the analog preprocessing section. Usually the one that gets the brunt of the low E and A strings. In all of these I've seen that was the fault when only one or two strings were out. Oh, did have a pickup once with a couple of coils out, sweat induced corrosion with failed repair attempt by another. That was unique.

In general these are well worth fixing. The guitar itself is a decent Carvin and the MIDI conversion is better than anything from that era (yeah, Roland, I'm talking to you) and still very much valid. The AXON beats it, but not much else. They are very playable and I've got a few customers still gigging the things regularly.

Hope this helps.

[dr]

....let me look;I may have something-give me a couple of days..............dr

[Cliff Schecht]

Ronsonic, you wouldn't happen to know anything about the Casio MT-30 would you? I've had one apart for well over a year now and it simply refuses to work correctly. I get sound when I lay my fingers over the board (albeit HIGHLY distorted), but I couldn't figure anything out with an oscope and DMM. I replaced all of the electrolytics but what else goes wrong in devices like these?

Here's a link to what I have:
http://weltenschule.de/TableHooters/Casio_MT-30.html

[Ronsonic]

Ronsonic, you wouldn't happen to know anything about the Casio MT-30 would you? I've had one apart for well over a year now and it simply refuses to work correctly. I get sound when I lay my fingers over the board (albeit HIGHLY distorted), but I couldn't figure anything out with an oscope and DMM. I replaced all of the electrolytics but what else goes wrong in devices like these?

Here's a link to what I have:
http://weltenschule.de/TableHooters/Casio_MT-30.html

Afraid I'm unfamiliar with that beast. That you can provoke it into doing something is sadly encouraging. Sorry, can only suggest working the drill, grounds, supplies, clocks and chip selects until there's life in the digital domain and work the standard troubleshooting of the analog stuff.

[krhnyc]

....let me look;I may have something-give me a couple of days..............dr

Thanks dr,

Also, thanks Ronsonic... I gotta get this thing street worthy again. It's my trio guitar, I use the midi to bleed B3 or rhodes behind the guitar stuff.

[Mark Hammer]

Ronsonic, you wouldn't happen to know anything about the Casio MT-30 would you? I've had one apart for well over a year now and it simply refuses to work correctly. I get sound when I lay my fingers over the board (albeit HIGHLY distorted), but I couldn't figure anything out with an oscope and DMM. I replaced all of the electrolytics but what else goes wrong in devices like these?

Here's a link to what I have:
http://weltenschule.de/TableHooters/Casio_MT-30.html

The person you want, Cliff, is one Robin Whittle, in Melbourne AU if I'm not mistaken.  I purchased Robin's document explaining mods to the Casio M-10 some 27 years ago (following up on an article in POLYPHONY from 1982 or so).  Though my beloved M-10 is sitting apart waiting resurrection at the moment, Robin's mods worked exceedingly well for a number of years (killer organ sound) and were really one of the earliest examples of what came to be called "circuit bending" that I can think of.  Robin had also published mods to other 1st and 2nd generation Casio keyboards in POLYPHONY way back.  A google search indicates that he's moved on to other things (like CSound) since then, but perhaps he has some files sitting around that will tell you what you need to know.

[Dan N]

I purchased Robin's document explaining mods to the Casio M-10 some 27 years ago (following up on an article in POLYPHONY from 1982 or so).

Here's something:

http://www.firstpr.com.au/rwi/casio/

Funny, this is my least favorite of the old Casios.

[dr]

Khris-email me and I'll send you what I have so far-11 PDF pages.....I know I have more and still I am looking!..........dr

[Ronsonic]

There's someone with the answer!

[dr]

.....Khris-I sent it out to you-let me know if it arrives OK..........dr

[lvs]

This page might help too, was up a few years ago and now in the wayback machine :

http://web.archive.org/web/20050830101700/http://homepages.donobi.net/mcd/mg500.htm

[dave-tutt]

Hi folks

Just to let you know. I have been repairing many of these guitars over the past 3-4 years as well as their voiced machines the PG380 and so far all of them have recovered well from replacing all the surface mount caps on the boards. Be aware that some caps are fitted without the -ve end of the cap marked either on the part itself or the board. The +ve is the side of the cap with the corners cut off.
I do not fit more surface mount caps as the boards that I have had through the workshop are all damaged to a degree and need to be cleaned and carefully scrapped away to stop further etching of the board. Be aware that the 33uf or 47uf power line decoupler on the top board in the 510 is prone to eat the track away beneath it and that this track goes in several directions. If you get a guitar that produces no output then this is the first place to look. You will see that the tune LED's on the control panel do not light when this has happened.
Use good quality standard lead electrolytics in all places in the guitar and you can't go wrong. Ensure you also change the caps on the lower board in the 510 as you will see with a magnifying glass that the electrolyte is leaking and the board is already in peril. There are no analog level caps on this board as far as I can tell. Being an old fashioned engineer I use my 38 years in the business to fault find and repair so I have little need to delve too deeply into the circuit technology. However, since these older chips were fairly rugged and not particularly power hungry these guitars are unlikely to die with anything serious.
The connector board is usually also full of bad joints after some 20 plus years so get in there with some solder and refresh the lot.
If you need to know more or need my help then by all means drop me a line.
Dave

[wavley]

I have a pg-380, replace all the caps.  I'm in the process of doing so myself, there are a lot of them and you'll have to take it completely apart.  Someday I'll get mine back together.

[dave-tutt]

If you fancy driving something like the Roland GR33 with the 510 then just set the midi switches to poly and channel 16 as a good starting point. That always works. Beyond that and if you don't have the original Roland guitar electronics you can play around with the settings on the GR33 and therefore get some better basic control of the thing.

I have also found that the Casios drive things like the excellent Alesis Nano Bass and the octave switch on the guitar shifts the sounds very nicely. The Casio volume control (midi control of the level at the voice module) actually works with the Alesis very well but not with the above mentioned settings on the GR33. Next time I get a pair in I will find out what the settings are to make it work!

Going backwards however, and using a pair of old Yamaha FB01 voice modules it is very obvious how voices on synths have improved since this giutar (and this module) was made!

Dave

[markeebee]

BTW.....if anybody has, or knows of, a 510 for sale I would very much like to buy one.