Sirius 24-slave lost

[pietervanemelen]

Hello,

We had a complete power cut and when the power was fixed again i got the message flashing "SLAVE LOST" on my sirius 24.

And all the channels give maximum output although all the faders are in zero position.

The desk was never used in slave mode.

Even trying to go to "super user" mode is not possible.

 

When switching the desk ON it say first "SLAVE ONLY" (very shortly) and then continues flashing "SLAVE LOST".

 

The desk does not react on any button push, switch change or fader change.

Please help asap (even electronic issues I can handle). I repaired the desk already twice but I can not figure out this problem.

Is there a way to reset the software (go to default factory settings)?

We need the desk operational by tuesday!!!

[KWR88]

This may not be easy to fix in the time scale you require, as my best guess is the power has caused a surge through the system when it has come back on.

The “slave lost” is from experience a fault with the RAM. It can get it self locked out if it has been spiked with a surge.

Something that you could try is remove the RAM IC from it’s socket for a few minutes and then replace it.

You should then hopefully get the “slave only” which will then allow you to get into the super user to turn it off.

If not then this may be due to a damaged IC. The problem is that there are several IC that may be causing this not just the RAM.

You could be looking at the main processor, EPROM on any one of the address decoders.

[pietervanemelen]

Ok I will give this a try. But can you mail me the IC numbers (and types)of the Ram and the address decoders (I do not have the schematics)?

But thanks already for the quick reply.

[KWR88]

It's a 32k RAM, it should be labelled on the pcb where it is.

[AlRamsay]

Hi Keith,

Can you cast your memory back.....

I've got a Sirius that has developed the same problem as described above.

I've also got a donor desk that I'm swapping IC's with.

I have removed the 32K memory chip and replaced it with no effect, I've also swapped the processor IC25 and the two eproms IC22 and IC23 and stil have the same problem.

Which chips are the address decoders?

 

Kind regards

 

Alasdair

[kgallen]

1 hour ago, AlRamsay said:

Which chips are the address decoders?

I don't know the internals of this desk but I suspect you're looking for some chip numbers that start 74. Maybe something like 74xx138 (where xx are likely to be some letters like LS or ALS or HC or HCT for example).

[iank99]

18 hours ago, AlRamsay said:

Hi Keith,

Can you cast your memory back.....

I've got a Sirius that has developed the same problem as described above.

I've also got a donor desk that I'm swapping IC's with.

I have removed the 32K memory chip and replaced it with no effect, I've also swapped the processor IC25 and the two eproms IC22 and IC23 and stil have the same problem.

Which chips are the address decoders?

 

Kind regards

 

Alasdair

It's a damaged track on the PCB after the battery was slow in being replaced & it's going to take ages to find it...

How do I know? I just repaired a Sirius Mk1 (in fact two - their own & one I sold them as a 'spare') for a drama group in Blackpool that was doing the same thing & it taught me a lot of new swear words

You're looking for continuity on the track between pin 7 of IC21 and Pin 1 of the DIN slave socket & to check the solder joints on the components on that line. The damage is likely to be localised around the PCB tracks where the battery is - ensure the tracks are cleaned, the old battery acid neutralised & any suspect areas linked over with some hookup wire. It's going to be painstaking - if you're lucky, then you might strike lucky quickly.

I note that you've swapped chips already (I did the same to no avail) which also suggests it's track damage. If you don't have Sirius main board schematics then please DM me here or contact me through my website & I'll eMail both versions (I will NOT attach them here to a topic).

[KWR88]

Hi Alasdair,

From what you have given i would agree with Ian that you may be looking at a corroded track around the battery area.