Sirius 24 putting out 17V

[Pritch]

Hello, all knowing Zero88 people.

 

I'm trying to resurrect a Sirius 24. At first it was having issues with garbled displays all over the front panel, so I opened it up and reseated a few ribbon cables (some of which were so loose they fell out as soon as I touched them).

 

Whilst I had this open, I checked the battery, which gave a reading of 1.7v, so I'm guessing that I should probably replace this.

 

I also noticed that I couldn't see any DIP switches where the manual told me they should be. In fact, the board seemed to be a somewhat different design to the one in the manual. The battery was over on the right hand side of the board (with the desk upside down and the outputs pointing away from me), whereas the manual told me the battery should be near the back plate.

 

Now, having put the desk back together, the displays seem to make a lot more sense, but:

 

1. Output LEDs 1 - 20 are permanently on. 21-24 are permanently off.

2. If you put a meter between any output and 0v, you get 17v. I've tried setting the internal jumper to 10v and 15v output, and it makes no difference. Even if you flick the DBO switch, it carries on outputting 17v, even though one of the displays on the board has changed to say 'DBO'.

 

Anybody got any ideas?

 

Thanks, Huw

[frogsurf]

I'm not support staff... nor am I familiar with that console...

 

but I think those dip switches are your solution. If the desk has been misshandled (dropped) the dip switches that "address" the groups of faders can move out of place.

 

IE- The symptoms that you describe cross-mojo-nate with out of place fader dip switches on other Zero-88 products.

[KWR88]

Not sure but I may have already answer this in a private e-mail.

 

The dips switchs you are talking about are on the Mk1 sirius only, and you are correct the PCB lay out is different to that of a MK2.

 

I would first look at replacing the battery on this desk. When you remove it check out the area under it for signs of corrosion damaged as there are a lot of track and componts in this area that deal with the fader circuit.

 

It could be a fault with the output delay circuit.

e-mail me on krogers@zero88.com to get some more info once you have done the battey.

[Mars]

Ground missing on the output section, output demuxers (4051) or the outputbuffers (LM324) blown.

That 17V is the supply voltage of this circuit, and if you get this at your outputs, they're just a bit 'offset'.

[Pritch]

Cheers both.

 

It's been put aside for the moment anyway. Fingers crossed, I'm told there might be enough money lying around somewhere for a Frog and a brace* of Betapacks, so I might not be needing to resurrect the Sirius after all!

 

* Is this the correct collective noun for Betapacks?