Help me Jamma wire for the first time...

[slapaham]

OK, so this seems pretty straight forward - however, I have a couple of queries and I'm also a bit nervy that I'm going to wire it up wrong and blow something up!

Anyhow, my cocktail table's speakers have no indication as to which side is + and which is -

The colours are exactly the same and the terminals also... can I just attach to whichever - or does it have to be a specific way around?

Next up is the monitor set-up - I have red, blue and orange wires as well as grey and white coming from the monitor... orange!? Would I be right in thinking or at least guessing this would be green (confusing as that sounds!) but the tools that made the cab coloured it orange instead!?!?! Also, I take it, from my experience, if I wire the white and grey wires round the wrong way, no damage should be caused as these are just sync and ground - the image would just a scramble if they were the wrong way around?

Another question - my PSU hasn't got a -5V - will this matter? Obviously I want be able to play games that require -5V but if I just tape the end of the wire coming from the loom that should be alright shouldn't it?

Sorry if I'm being a bit over cautious but I like to make sure I'm doing things properly if I haven't done them before!

Thanks guys!

[Kman-Sweden]

You could use a small battery to check what is + and -.
See it the speaker cone pops outwards (+) or inwards (-). Please correct me if I'm wrong.

[CheffoJeffo]

Never trust wire colours -- trace them back to the harness. Having said that, I've mixed up video signal wires without bad consequence.

You'll be fine without -5V, although some games require it.

[slapaham]

Cheers guys... trouble is the monitor positioning makes it bloody awkward to trace the wires... I'll keep you posted!

[BobA]

No need to worry about plus and minus on speakers unless you are wiring stereo and need them in phase.  A single speaker arcade cab can be wired any way you want.

[slapaham]

No need to worry about plus and minus on speakers unless you are wiring stereo and need them in phase.  A single speaker arcade cab can be wired any way you want.

Ah, cheers chap... not being an expert I wasn't sure, but I had a feeling that might be the case looking at the inside of the cab!

[slapaham]

Well, I have sound and the buttons and sticks and coin mech seem to be wired up correctly (going on the basis of the sounds I can hear!) also tried the jamma connector with the multimeter and it's getting the right measurements but I'm getting confused by the monitor... how exactly do I wire up the power for the monitor from the arcade PSU? It obviously needs something to power it...

[Kman-Sweden]

Sony think you can power it from your arcade psu. mine, at least, doesn't supply more than +12v.

[slapaham]

Mine does have a terminal for +24v?

[slapaham]

In theory... as the monitor is still connected to the original power supply, if I plugged that in, as well as the new PSU then surely that would do it wouldn't it? then I could just put a 2 way power adaptor inside the cabinet to power both from one plug? Or is there an easy solution to get the monitor powered from the one, new PSU because I guess that would be a neater solution...

[CheffoJeffo]

Powering the monitor is someplace where you can do some damage -- particularly vis-a-vis isolation transformers.

Rather than confuse you with semantics, can you post some pics of how things are hooked up ?

[slapaham]

Powering the monitor is someplace where you can do some damage -- particularly vis-a-vis isolation transformers.

Rather than confuse you with semantics, can you post some pics of how things are hooked up ?

Will do in a little while...   

[BobA]

A jamma cab will not have 24v in the ps.  Where are you getting the 24V supply voltage?

[slapaham]

It's a terminal on the arcade PSU I bought... I've never heard of that either!!

[slapaham]

Just to add - I tried the solution that I suggested and it worked spot on. As the cocktail has one of those giant, ancient transformers it might be a good idea to have 2 psus running things. A modern PSU for the jamma side of things and the ancient PSU for running the monitor at the correct voltages, etc. I've read up on old PSUs varying in what they output and so rather than faff and tempt fate I think sticking with it is for the best.

Now that I have it up and running, it's just a case of making it nice and tidy. A 2way power adaptor inside will make it neater. As this cocktail table is pretty ancient, I think this is probably the most sensible way of approaching it.