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SDS6 issue

SDS6 issue

2014-10-29 by Jim Barber

I have an SDS6 that has an issue with the scan on the matrix. Everything works. The Led’s lite with the pattern but when you play one the unit doesn’t scan. I assume it is an internal clock because if I inject an external clock it works. I assume there is a chip that needs replacing. Wondered if anyone could point me in the right direction. Maybe the 311 chip after the tempo pot circuit?

Jim Barber
lewisbarber@sympatico.ca




Re: SDS6 issue

2014-11-09 by philmurr@...

Did you ever manage to fix this ?

You can check the 311, D-A converter and the VIA by altering the tempo pots and seeing if the readout changes.

Sounds like there might be a problem somewhere between the sync select switch on the expansion board and where that tells the CPU you want to use the internal clock - have a look at IC6 and see if that's doing what it should...

Re: [Simmons Drums] Re: SDS6 issue

2014-11-10 by Jim Barber

Thanks. I have ordered a 311 and will be in in a week or so. I am not getting the sync signal, only if I supply one to the sync in jack.

Will let you know how it turns out. The SDS6 is a great drum machine as it is so easy to use. I have had drum students use it to listen to drum beats. It is easier to learn when they can listen to them, rather than try to play by just reading them. My SDS6 also has the midi feature.

Jim

Sent from my iPad

On Nov 9, 2014, at 10:34 AM, philmurr@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

Show quoted textHide quoted text

Did you ever manage to fix this ?

You can check the 311, D-A converter and the VIA by altering the tempo pots and seeing if the readout changes.

Sounds like there might be a problem somewhere between the sync select switch on the expansion board and where that tells the CPU you want to use the internal clock - have a look at IC6 and see if that's doing what it should...

Re: [Simmons Drums] Re: SDS6 issue

2014-11-10 by Michael Buchner


Hello,
I once had a "midied" SDS6 in the shop with the same fault. Here is what I did:
The "midied" SDS6's don't have a working reset button any more, this was cut off in the factory (the red button on the CPU board has no function). You can reset the CPU if you touch the pins of the I/O with your fingers (now don't laugh, it works). If you don't know what the I/O is, it is one of the big chips, the lower one. Open the SDS6 and simply grip the pins a few times.
Did you move the sync switch already a few times? If there are stains on the contacts, it even doesn't work.
If you need the schematics: I have these and can send.
Best
Michael
Show quoted textHide quoted text
----- Original Message -----
Sent: Monday, November 10, 2014 2:35 AM
Subject: Re: [Simmons Drums] Re: SDS6 issue

Thanks. I have ordered a 311 and will be in in a week or so. I am not getting the sync signal, only if I supply one to the sync in jack.

Will let you know how it turns out. The SDS6 is a great drum machine as it is so easy to use. I have had drum students use it to listen to drum beats. It is easier to learn when they can listen to them, rather than try to play by just reading them. My SDS6 also has the midi feature.

Jim

Sent from my iPad

On Nov 9, 2014, at 10:34 AM, philmurr@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

Did you ever manage to fix this ?

You can check the 311, D-A converter and the VIA by altering the tempo pots and seeing if the readout changes.

Sounds like there might be a problem somewhere between the sync select switch on the expansion board and where that tells the CPU you want to use the internal clock - have a look at IC6 and see if that's doing what it should...

Re: [Simmons Drums] Re: SDS6 issue

2014-11-11 by Jim Barber

Ahh. I wondered what that switch was!

Assume you mean the 6522. I'll touch the pins with my fingers. Any certain pins?

I have a schematic but it is very hard to see the pin numbers and some of the characters because it seems to be a photo of the schematic that was scanned by a scanner that was one of the earlier low res devices. If you have a schematic that is higher res, please send.

SDS6 serial # 86

Jim

Sent from my iPad

On Nov 10, 2014, at 7:11 AM, 'Michael Buchner' buchnerelectronics@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:



Hello,
I once had a "midied" SDS6 in the shop with the same fault. Here is what I did:
The "midied" SDS6's don't have a working reset button any more, this was cut off in the factory (the red button on the CPU board has no function). You can reset the CPU if you touch the pins of the I/O with your fingers (now don't laugh, it works). If you don't know what the I/O is, it is one of the big chips, the lower one. Open the SDS6 and simply grip the pins a few times.
Did you move the sync switch already a few times? If there are stains on the contacts, it even doesn't work.
If you need the schematics: I have these and can send.
Show quoted textHide quoted text
Best
Michael
----- Original Message -----
Sent: Monday, November 10, 2014 2:35 AM
Subject: Re: [Simmons Drums] Re: SDS6 issue

Thanks. I have ordered a 311 and will be in in a week or so. I am not getting the sync signal, only if I supply one to the sync in jack.

Will let you know how it turns out. The SDS6 is a great drum machine as it is so easy to use. I have had drum students use it to listen to drum beats. It is easier to learn when they can listen to them, rather than try to play by just reading them. My SDS6 also has the midi feature.

Jim

Sent from my iPad

On Nov 9, 2014, at 10:34 AM, philmurr@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

Did you ever manage to fix this ?

You can check the 311, D-A converter and the VIA by altering the tempo pots and seeing if the readout changes.

Sounds like there might be a problem somewhere between the sync select switch on the expansion board and where that tells the CPU you want to use the internal clock - have a look at IC6 and see if that's doing what it should...

Re: [Simmons Drums] Re: SDS6 issue

2014-11-15 by philmurr@...

Whilst we're talking about the SDS6, can anyone tell me the value of C16 on the expansion board, mine is missing and the schematics don't have values on them :-(

Re: [Simmons Drums] Re: SDS6 issue

2014-11-15 by Jim Barber

I just spent the last 10 minutes looking for C16 on my expansion board and could not locate it nor could I find a silk screen indicating the part. Tell me exactly where it is on your board and I'll look again. I suspect that the part was removed from the design but your board may have been built before they removed it and the silk screen was indicating C16 on your circuit board. It is on the schematic but not sure what it would have done other than maybe reduce noise. They may have removed it if they found that it didn't have any affect on the noise or being in the circuit.

Jim

Sent from my iPad

On Nov 15, 2014, at 1:33 PM, philmurr@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

Show quoted textHide quoted text

Whilst we're talking about the SDS6, can anyone tell me the value of C16 on the expansion board, mine is missing and the schematics don't have values on them :-(

Re: [Simmons Drums] Re: SDS6 issue

2014-11-16 by philmurr@...

Thanks Jim !

Mine definitely had the component in at some point as you can see where the legs have been cut off -

With the sockets and switches facing downwards, the top left of the board has IC1, then IC2 to the right, then IC3 to the right of that. C16 is immediately below IC3.

Have you got your SDS6 showing the LED trace yet ?

Re: [Simmons Drums] Re: SDS6 issue

2014-11-16 by Jim Barber

No Not on my board. It has been removed from the circuit. Guess mine is a newer board as it doesn't show the cap silk screened. It is serial number 86 and is MIDI capable.

Hope that helps.

Haven't had a chance to get the LED trace working. I am still waiting on components. I am a couple of hundred Kilo-meters from a component shop so they are in snail mail.

Jim

Sent from my iPad

On Nov 16, 2014, at 11:33 AM, philmurr@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

Show quoted textHide quoted text

Thanks Jim !

Mine definitely had the component in at some point as you can see where the legs have been cut off -

With the sockets and switches facing downwards, the top left of the board has IC1, then IC2 to the right, then IC3 to the right of that. C16 is immediately below IC3.

Have you got your SDS6 showing the LED trace yet ?