Phoenix display problem

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Skeet

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Retroman839 said:
Yeh cool that’s correct ..

Pin 5 only for separate sync
But your game don’t need it .

Sync pot on controll pcb have you tried dialing it in ?
Sync polarity switch ?
Do you see a Small three pin connector ? Near video in connector ? ( only
On usa variant of mtc 9000 )
Click to expand...
So it must be something else....
I have had loads of problems with Phoenix and Pleiades boards before. They won't display on VGA monitors with the usual converter boards that other arcade games work with. I even tried building the "Sync sorter" mod that is supposed to work, but didn't have any luck with it.
Until now I did not have a working Arcade CRT, and could only get Phoenix / Pleiades to display on a Wells Gardner LCD arcade monitor.
I thought it would work on this new monitor as the original Phoenix CRTs were Hantarex as well.
 
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Skeet

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Retroman839 said:
Maybe componants have weakened and cannot lock .

Like my
Puzznic
Click to expand...
Yeh, I was going to take a look and at least re cap the monitor where required.
That might sort it. Maybe it can cope with the super space invaders signal, but flakes out on the Phoenix signal as it definitely is known to be a bit funky.
 
Retroman839

Retroman839

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If you have an oscilloscope you can
Compare sync timings to the schimatic.

That would tell you
If your boards componamts have weakend .. attenuation /amplification etc
 
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Skeet

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Retroman839 said:
If you have an oscilloscope you can
Compare sync timings to the schimatic
Click to expand...
Great idea. I do have a scope.
I have to say though, I'm a bit scared of CRTs!
I'm used to working on HIFi, even high voltage professional amps and haven't tried scoping CRTs.
Its time I had a go.
 
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Skeet

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Done some reading and it appears that Phoenix/ Pleiades boards as well as having a non standard sync timing, they output a positive sync signal rather than the usual negative sync.
I'm going to try the sync splitter from Console Mods with a Schmitt trigger inverter (74LS04) on the output of the Phoenix board. (Suggested by
breadel on MOG)
If my Monitor does have a switch for positive sync, I could try that-, but it's a bit faffy though if I'm going to be swapping from super space invaders to Phoenix.
 
Retroman839

Retroman839

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I don’t recall if you said you had used the monitors sync adjustment potentiometer ?
Have you done this ?

It’s on a little pcb with a few other picture adjustment potentiometers.

Possibly away from the chassis on an Extention lead ..
That runs off the back of the monitors chasiss .

May be near pcb or even behind glass on front of monitor frame.

Could even be be fixed round the back
As you can use mirrors to see front screen when adjusting


You need to find the adjustmemt
Pot for sync level adjustment
 
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sukhbir

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Skeet said:
Done some reading and it appears that Phoenix/ Pleiades boards as well as having a non standard sync timing, they output a positive sync signal rather than the usual negative sync.
I'm going to try the sync splitter from Console Mods with a Schmitt trigger inverter (74LS04) on the output of the Phoenix board. (Suggested by
breadel on MOG)
If my Monitor does have a switch for positive sync, I could try that-, but it's a bit faffy though if I'm going to be swapping from super space invaders to Phoenix.
Click to expand...
My Phoenix pcb is negative sync,I’ve repaired lots of these in the past and they are negative video sync And rgb signals at positive max 2volts peak.
when you see the signal on the scope you are seeing a positive sync signal but when it goes to the input of your monitor it is decoupled to negative sync.
 
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