1084S-P LOPT+HOT replace

the problem your having is not flyback related,its video signal related.

you need to check the video input area.its probably sync related if its on all of them through one computer it may even be the computer.
 
I just tested it on another Amiga and it's the same.
I also checked it without any connection (i.e. no video cable plugged in, just powered on by itself) and same problem.
It didn't have jailbars before with original flyback and now has this problem after flyback was changed so I'm leaning towards flyback issue or missing ground somewhere on the flyback causing this. Meaning maybe the re-manufactured flyback isn't 100% compatible?
The only other thing I haven't tried is a different video cable but I only have 1 Amiga cable. Though with the same cable it was ok before changing the flyback. It seems to be an endless loop that always comes back to the flyback ;-)
 
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if it had a missing ground the flyback wouldnt work.

and if it wasnt 100% compatible it wouldnt work.

also the flyback(lopt) mostly deals with the horizontal on screen,thats why you need to look at the sync input inside the monitor.
even with no signal injection.
just changing the lopt isnt a calibration after repair,thats why reading the service manual is very important.if you can get one for it.
 
I have schems for the monitor (found on Ray Carlsen's site)
http://personalpages.tds.net/~rcarlsen/cbm/monitors/1084 Philips OEM/
http://personalpages.tds.net/~rcarlsen/cbm/monitors/1081/MAIN.jpg
http://personalpages.tds.net/~rcarlsen/cbm/monitors/1081/PS & CRT.jpg
http://personalpages.tds.net/~rcarlsen/cbm/monitors/1081/RGBI.jpg

there isn't a publicly available service manual for the 1081 as far as I know.
I don't know much about how monitors work. My repairing knowledge is mostly focussed to logic/cpu circuit boards (such as Amiga motherboards, arcade PCBs etc, including surface mounted stuff.... pretty much anything except monitors ;-)
so what am I looking for on the sync input and what would I do to adjust it if it wasn't right?
Can you point it out on the schematic sheet? I'm not even sure where to look on the schems for the sync input signal
 
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you say you have four?

they all do the same thing?

you also have to be absolutely sure what schematics/service manual your looking at.
 
yeah, 4. I bought one new in 1985, the others were given to me by friends because they were dead. I replaced caps, some transistors, flyback & power switch. re-soldered many joints on the boards (known cracked joint faults at connectors etc on the back)
all work, all with same fault.
the schems I linked above match the monitor I bought (the 1st one). the others have minor PCB differences. Regardless, one is identical to the schematics.
 
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ok,i had a thought.
do you still have any of the old flybacks? if so,did they have a label on them?
can you read the label and post the whole number on it here?

if there the same as the schematics above they are philips chassis,you may of got the wrong flybacks.

i dont have a 1081 here but i do have the monitors for the schematics you looking at,which are a 1084-p

also,what are these minor differences you talk of on the pcb?
have you tried the vcr switch on the back?
 
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My monitor has Philips label inside on the tube M34EAQ10X
The circuit board has number 3138 103 30854
The flyback has number PVP AT1201/T11 30161 TY E39144
This is the one I bought....

http://www.hrdiemen.com/reparation/flyback/model/6489
http://www.hrdiemen.com/reparation/flyback/scheme/6489

Their cross-reference says it fits 1081 and 1084 (and other various models listed)
They have others to suit Commodore monitors but out of all of them, the HR6489 is the only one that has the same pin layout. The flyback looks identical to the original in every way.
The actual place I bought it from (local distributor) had the same part number in their catalog for one of my other monitors (not the original Philips I bought myself back in '85) but listed it as suiting 1084AU (mine is 1081AU). At au$45 each I figured I'd just buy them and try and at least one should work since at least one has an exact matching part number. Prior to ordering I had no idea they were made by HRdiemen. I ordered the one that matched and the HR6489 is what arrived in the post.

The differences on the PCB were mostly related to one of the video chips used and it's placement but basically the same.
The Philips OEM link filenames were named as 1081 but yes they are 1084 schems. according to Ray Carlsens pages, this is the schem for the 1081....
http://personalpages.tds.net/~rcarlsen/cbm/monitors/1081/MAIN.jpg
Looks like not exactly my model though because that schem has number 3138 105 21581 (mine is 3138 103 30854)
I didn't compare every part but all of the major TDA ICs are the same. Also all of the pins on the HRdiemen schematic for the HR6489 match the 1081 schematic flyback connections. I think if it was very different it wouldn't work at all. But it does work.
This is where the problem gets impossible because there are so many different versions of Commodore monitors and most of them don't have available schematics.
The 1084 flybacks have a totally different pin layout in a half-circle and mine is a rectangle so it looks to me like this flyback is correct for this model. But it may not be 100% compatible and impossible to know for sure because of the vast variety of Commodore models out there in the wild.

Anyway it works but with jailbars. It's more pronounced on the workbench screen but they are less noticeable or virtually invisible when playing games.
Talking to a friend who repairs monitors he said the lines could probably be reduced or fixed by adding a capacitor or resistor somewhere.
If there isn't an easy fix I'll live with it (assuming you or someone else can't help?)
 
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does yours have the vcr switch on the back? and it works I,E: has continuity across it when pushed in and out,worth a try i suppose.

it apparently is to allow for odd sync signals.i never use it though.(on mine it doesnt really do anything)

did you change the hot transistor when you changed the flyback? i forgot to ask.

also,did you do anything to the power supply? check voltages on the main rail feeding the flyback i always check it when i replace them.it should be around 125-130 volts dc.
also check the capacitors on the supply.a bad one there might give that effect.and may show onscreen as distortion.
its not impossible for this to happen,especially when a flyback dies.it can put sustained load on the smps supply sending parts bad.
and diodes on the mains end before the supply to turn it into dc...
thats all i can think of off the top of my head...

i have to assume you know how to check those:)
 
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the voltage on the PSU was ok
Ignoring the ones that were dead, I didn't do anything else to the electronics because this Philips 1081 worked. there was only a high pitched squealing but the picture was perfect. I didn't see any point messing with parts that are working fine as-is. the problem only occurred after changing the flyback and only the flyback was touched. the others had caps, HOT and other stuff changed but have the very same fault anyway.
I just tried the VCR switch. it shifts the picture horizontally 1 pixel to the right. no effect on actual picture or quality. so basically it does nothing.
 
its an odd fault really...very odd.

i have never had a monitor ive repaired go like yours after a lopt replacement,ever.(ive done more than a few now,and one or two that required a full strip down to fix them)
all of them had there own unique problems from power supply failure to lopt to audio problems(some all at once).plus a few many most wont see in there lifetime...and some ive admitted to being self inflicted by myself during a repair,lol
now that ive seen this,im making notes on it for future repairs in case i run into it,i honestly havnt seen anything like it.
or even anything similar for that matter.
if you think ive been lucky,you would be wrong.:)

EDIT: can take a picture of the rear of your monitor with the sockets in shot.and show which socket your using,im assuming your using the analogue rgb port.
try to use the amiga through composite on the composite port and see if that has the same effect with the bars.
there is a reason why i want you to try this,as you probably understand.
then depending on the answer i get, ill try to give you response that you can try that may be fairly easy if you have some tools and soldering iron:)
it may involve looking for a component on the board.

i also need to know if you fitted the lopts and what you did while installing them,as in:did you set the brightness to certain level before turning up the screen knob on the flyback?
or,did you just fit the lopt and turned up the screen knob and it worked?
 
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I'm using the Commodore-supplied cable that came with the A1000 when I bought it in 1985 (I no longer have the A1000)
The cable is 23 pin D connector to SCART. I don't have an RGB analogue cable.
Have tested it with all Amigas in my collection (A500, A500+, A600, A1200, A2000(x2), A3000, A4000). All the same.
The rear is the same as shown in the manual here... http://personalpages.tds.net/~rcarlsen/cbm/monitors/1081/ADJ.jpg
I fitted the LOPT and set the screen control so the raster retrace line doesn't show then adjusted the brightness to get the best picture (i.e. the standard procedure when setting up arcade monitors)
I have a room full of equipment for doing electronic repairs (mostly for arcade PCBs) and have been repairing stuff like that since about 1995. Soldering is no problem (even surface mounted SOIC/SOP/SOJ/PLCC/QFP and BGA)
I rarely touch power supplies or monitors though.
I just tested the b/w composite coming out of my A500+ and it's the same (with jailbars). As I said the screen has jailbars even without any video cable connected.
 
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I have a Commodore 1084S-P1 squeals when turned on so I assume it's the flyback, which seems to be a correct assumption after desoldering and measuring.

donberg.ie has the HR7533 (AT2079-37593) that is needed but I also found it in Serbia, for "1050 din" which is just $10.
http://www.proelectronic.rs/SPLIT-TRAFO-AT2079-37593-HR7533-AT2079-37593-2438.htm

It's a bit hard to handle Google translate and such but I think I got something through, I'll see if I get a reply and what shipping cost it is.
 
They didn't want to sell the cheap one to me, some deal they had with ASWO, so I registered there only to find that they had the same flyback for 1/3 of the donberg price... But I had already bought it from donberg.

Got this today:

2015-05-25 13.47.25.jpg
Chipped and cracked again - not as bad as my first HR7506 but still... It was well packed and re-packed, don't think it happened in shipping. The top ferrite is glued on at a slight angle - seems the damage could have been done then.
I have complained again, don't know if I can safely use it.


EDIT:
Got a reply, they were going to send a new one, but they didn't have it in stock so it'll take a week or more.
 
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I gave a good read of the thread but I have a couple of questions (naturally :LOL: ) since I want to get some spare parts for the future for my 1084S-P1 monitor.

a. What is the correct replacement lopt for it? Is it HR7533 or HR7506 ? I can see here the author says it's 7533 and I read in the thread about both of them. I can get 7533 locally and I tend to believe this is the correct replacement lopt - ofcourse any comment is welcomed on this.

b. Regarding the HOT, it's a ST BU508A I can source locally the Philips BU508AW , it seems it's a direct replacement, can someone verify just to be sure 100% ?


reason I want to get replacements is because today all of a sudden on a working and recapped/cleaned arcade chassis (not the humidity damaged one from the other thread) the LOPT (HR7191) decided to suicide. Quite a bummer for something that was looking good... so I assume that along with the LOPT I will need to change the HOT as well - it also happens to be a ST BU508A ... so I thought it would be a good idea to have some parts for the 1084 as well...
 
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correct lopt for a 1084s-p1 is a hr7533

correct hot transistor is a BU508AF(mentioned in the service manual) or D1577,if you get one with a metal tab use a sil pad to insulate between transistor and heatsink or itl blow the fuse in a short


thats 100% info


1084S-P which is the earlier model,uses a HR7506 and uses the BU508A and D1577 hot transistor


all you have to do to find out is read the label on the rear as a identifier for the chassis


the HR6489 is for a very early model,this has a separate screen and focus unit on the tube neck assembly(neck boards can be the same as used for the hr7506),it can be identified by the square outline on the pins on the underside of the pcb instead of a U shaped pin config,they are not interchangeable

i can put up a picture of this model,if there is any confusion,although i dont think there are alot of them around now maybe

there was also an early release and late release boards with stereo and mono audio configs,but i wont get into that or itll get veru confusing,and not very relivant to this post
 
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I´m planning to resolder DB15 connector on a 1084s-p1 as it has come loose. What is the safest tool and best ground connection to discharge monitor? Photos and link to tools please :)
 
Screwdriver with good insulation and a copper wire connecting it to a ground point - I use the ground pin on the mains in my office. Just do this and you'll be fine:

 
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that pic is hilarious!! 20000 volts could come up the screwdriver and to his hand. looks like he's touching the metal shaft of the screwdriver anyway so he can kiss his a$$ goodbye ;-)

you don't need to remove the chassis to re-solder the DB15. It's accessible with the cover off so just re-solder the pins. I've done that a few times, works well.
 
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Probably not as stupid as poking with the pair of pliers first - when you can easily shove a flat head screwdriver under the suction cup.
Clamp on screwdriver looks like it can flip off at any time - that would be really bad...
 
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