1084ST Won't power on.

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lol,yeah the vat is a bit high.


EDIT:

when you get the lopt itll be set to the defualt of zero on both pots so dont worry if nothing appears on screen,so heres what you do.

install the hot and flyback.
make sure ALL connections are connected properly if not it may damage the lopt when turned on,that includes the neck tube pcb.
one connector on the neck pcb may look like it wont come out or its not soldered as it goes into plastic fitting,if you get stuck ill explain how to remove it to install the wire from the lopt.

turn the brightness to the middle most setting.

plug in a test card generator or computer and turn it on so it gets a signal at the monitor.

using a long screwdriver carfully turn the screen pot up clock wise till you get a picture thats semi clear with no horizontal lines and fills the creen,at this point there should be no noise coming from the set at all.
dont touch anything metal or any components in the chassi while doing this.

then set the focus by turning the focus pot clockwise until the picture is clear and sharp.

after that all the other adjustments are on the front/rear of the case.
 
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Good advice. It's coming from the manufacturer so they've said it will be about 3 weeks.

Three weeks I'm on the atari then, could be worse.
 
FYI you only have horizontal collapse, the reason you then get the dot in the centre is the PSU shutting down, you've still hot high voltage when the vertical deflections shuts off. You may be lucky with the LOPT but horizontal collapse is hard to do unless you have a split HV type monitor which id say this is far far too old to be.


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We'll see when the new flyback gets here. If it's not the LOPT - in which case I'll be annoyed because the test I was advised to do pointed to it being - then at least when I fix the other thing I'll have a monitor that doesn't make a horrible whining sound.
 
By pulling the LOPT you are running the monitor with no horizontal deflection and none of the secondaries running, its not going to tell you a massive amount apart from the PSU section MAY be good.

You really need to test the PSU section with a load on the B+ then you can accurately measure the voltages etc, a 60watt light bulb on the b+ is ideal.
 
this is turning into an interesting thread.

check post#6
 
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this is turning into an interesting thread.

check post#6

Unless I'm looking at the wrong schems which is possible as im only using my phone the b+ is 125 under load so I'd expect around 180 with no lopt or load.

couldnt find any schematics for this monitor,if you can link to them please do i would like to see them as well.

i dont think i would be expecting it read that high.
 
i know which one you mean.

dont know if its rare of not,but i like my steaks that way though,lol
 
There's a few that come up on a Google image search for 1084ST schematics but without having the chassis it's hard to know if any are the right ones. I don't have an ST version or I'd compare them.


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its not really all that hard.:)

if you can link them to the thread its just a process of elimination as i have all the others...
not just schematics,service manuals.

this is not a philips or deawoo chassis that im aware of.picture tube is a philips though.
problem with google search is its a generalized search engine.

personally i couldn't find any service manuals or schematics for this monitor at all(schematics only help upto a certain point anyway),if it helps any commodore dont/didnt make any monitors themselves.(that im aware of)
so i try to find out what chassis was in them.(and get the service manual for the chassis,which are far clearer anyway mostly)

all i did find was a few pictures of the chassis in this monitor and that was about it,lopt itself took an hour of research and cross reference to find an exact match.

if the schematics are for the 1084/s 1084/s p 1084s p1 cm8833 cm8833 mk2 1084s d/d1 etc,it wont be any of those through process of elimination.easiest way is to go by the lopt and none of these use that lopt at all.
if the one you was looking at had no references on it or in the schematic i would be able to tell by sight:)
 
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no worries bud:)


its not the lower three links(last one is mainly pictures anyway),one is a 1084p(second one down)ill have a look for the top one i dont immediately recognize it:)

EDIT: top one is 1084p as well:)
 
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Yes the last one is just info on who the manufacturer is thought to be.


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New flyback is here! I fitted it, and I get a picture!

New problem though. It makes a horrible high pitched noise.

Noise is definitely brightness related. If the screen is white, it is very quiet to silent. Watching demos can make it sing at different pitches when lighter or darker things are shown.
 
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might be a power supply problem,do you want to send it to me?

its easier than trying to have messages back and forth in the forum,and you are in the uk.
fault finding when its in this sort of state will be difficult mate:)

if your up for that ill take a look at it,and if parts need replacing thats what itll cost you...
or send me a pm with where you are,if your close enough i might be able to come a pick it up.

EDIT:if its liverpool thats too far for me,but a courier will be fine if its well packed:)
but..if you dont know what your doing dont mess with it.
 
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