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Hello,
Tonight my A1084S-P1 has stopped working.
It was powered on, then I heard a sizzle sound, then image has been reduced to an horizontal line in the middle of the screen.
so I power it off.
Now when I start it I still have a sizzle sound but nothing on the screen.
Sound:
https://dl.dropboxusercontent.com/u/...ibay/A1084.m4a
Can it be the Flyback ?
Thanks for the help :)
Great chances of messed up flyback and Horizontal Transistor also because all screen is cropped in a single line
can you do another video please with the sound you mention,the link dont really work for me.
maybe a youtube link?
i reckon the flyback is probably knackered and the hot transistor if its a high pitched sound,does the led power light come on?
although im pretty sure a horizontal line on screen is a vertical problem(vertical collapse),but as you now get nothing but a sound...
its probably wise to discharge the flyback and inspect the inards for bad solder joints,youll have to pull the main board for that though.
Here is the sound on Youtube : https://www.youtube.com/edit?video_id=iurNN3LiEig
I have ordered an AT2079 flyback replacement, unfortunately it has a one more pin than the original one.
The AT2079 Flyback:
https://dl.dropboxusercontent.com/u/...k%20AT2079.jpg
https://dl.dropboxusercontent.com/u/...%20%282%29.jpg
The one I have ordered:
https://dl.dropboxusercontent.com/u/...%20Flyback.jpg
Thanks
i cant see the youtube link mate.for some reason
the flyback you need is a hr7533
take note of the whole serial number its not just AT2079 there is more. its AT2079 37591
just send the one you have back mate if you can,if i had known i would of told you the replacement you need by the code on the flyback...
sorry about that.
and before you ask,the one you have cant be modified to work in your chassis.trust me i know.
EDIT: alternatively you could sell that flyback on here for what you got it for just mention the entire code on the box it came in or flyback,it will work in a 1084s it just wont work in your monitor.
here is a link for you,just to help you out a bit...you can take no notice of the last part of my thread as yours already has those parts fitted as standard.
good luck.
if you get stuck,i'll try to help you.
http://www.amibay.com/showthread.php...oma-Luma-added
EDIT2: looking at the pinout of the flyback you have got by mistake i would say it was a AT2079 30101 which is a HR7506,if that helps you out any mate...
you could probably confirm that as i cant see the serial in the picture you posted...
Hello,
Thanks for the answer... Yep! I must have been fooled because I see a thread with a guy who has fixed his 1084s with the HR7506... So yes, I bought the HR7506 :)
So from the sound you have heard, do you think the flyback is faulty ?
I have some questions:
1/ in your picture picture.php how did you put the black wire in the little box ?
BTW this on my monitor there is a metal shield around this part.
2/Why did have you added chroma/luma ? I won't have to do that ?
Thanks for the help.
sorry bud, i did not hear the sound your link dont work for me,if its a high pitched sound its the flyback...and the power light might not be coming on for you either.
if you could fix the link that would be great.
1,the black wire simply plugs into the connector mate(you just push the wire in),to remove the old one you twist and pull the wire (in a unscrew fashion,it dont matter which way its not threaded just try to not pull it straight out,its grip for the cable )and it will eventually come out.
the metal plate has to be unsoldered its shielding for the pcb...
oh,as you can see the red one is soldered on.
some chassis has the sheilding some dont but they are the same,i even have some that have the shielding on the main board you have to pull out.
i have a few of these and some have sheilding some dont,nothing to worry about they are identical otherwise.they just have to be unsoldered to get at the boards for repair,nothing too serious..
2,because your monitor chassis already has this i hope, as the commodore badged version of this philips chassis already has chroma luma parts already fitted,or..should have.
the philips CM8833 mk2 is a COMMODORE 1084S P1 internally its just the 8833 is missing the extra parts thats all.i have both by the way.and a few others.
The frame circuit is powered by the flyback transformer so dead output transistor or flyback transformer is defnitely your problem.
TC :)
absolutely right bas.
i would and have changed the transistor on these as well,there really cheap.
@roy the sound has been on Youtube as requested :) https://www.youtube.com/watch?v=iurNN3LiEig
@TC Thanks, do you have in mind the Transistors to check ?
PS: Actually the board is out and the Flyback is unsoldered.
Lets not jump to conclusions so soon. Original problem was not (there is no way it is) flyback or hot because horizontal line was visible on screen. Without flyback&hot there is no high voltage, no horizontal deflection and no image whatsoever.
It still could be problem only in vertical circuit (possibly even vertical coil) pulling down power supply voltages. Remove horizontal output transistor (and check it for shorts), does the sound still appear if you power it without hot? If yes, it is not horizontal problem.
the link still dont work for me mate,is it private?
give me a sec and i'll post a part number for the transistor....bas could probably confirm it as well.
EDIT: i think its a BU508AF...i think.
EDIT2: you could get a couple of these and try the transister first if you like.
Thanks Toni for sharing your knowledge. I really hope to fix this monitor :)
For now what I did... I don't know if it is a good test or not (but I think it is).
I took the datasheed of my flyback : http://www.donberg.ie/catalogue/line...s/hr_7533.html
And I put the ohmmeter between the pin 3 & 5... and... they are shorted.
that is the right flyback and if i was you i would change the hot transistor as well,put some some thermal grease on the back before you put the clip back on it.
some windings on a lopt(flyback) cant really be tested with a multimeter reliably.but,i have to say this the lopt in the monitor under normal working use does not make any noise that you can hear.
windings in these can short/bridge gaps in windings anywhere, and on the final windings they are so closely packed.
Hello,
Update :
I have unsoldered and tested the Horizontal Output Transistor (C3795B) with my multimeter (diode check) and it is good.
I also have unsoldered all capacitors around the Horizontal Driver Transformer and they are good.
Questions:
-Can I start the board without the Flyback on ?
-Can I start the board with the Flyback on (non connected to the CRT) ?
Thanks
Roy buddy, his hyperlink is wrong but the video is available if you copy and paste it.
Alternatively we can post it in the thread :)
https://www.youtube.com/watch?v=iurNN3LiEig
I have no idea how to fix it but it sounds like you have Crickets hiding in there :lol:
Without flyback or HOT it should be safe. Nothing will happen unless there is short somewhere else (=if you still hear buzzing sound there is fault somewhere else than in horizontal section).Quote:
Originally Posted by gibs
Check also deflection coils (coil around the CRT neck), vertical may be partially shorted, it can create that sound too.
With HOT and flyback connected, do you get horizontal line (turn brightness down to prevent phosphor damage) if you disconnect vertical deflection coil? (I think that connector is near the middle of PCB, near vertical IC, not near flyback). This is safe to remove if brightness is down. (Horizontal is not, see below)
Do you mean high voltage lead or horizontal deflection wires? Removing HV wire can be dangerous, really high voltages there. Don't do it.Quote:
-Can I start the board with the Flyback on (non connected to the CRT) ?
Horizontal circuit need deflection coils to work correctly (it is part of tuning), also without horizontal you would get extremely bright dot in the middle of CRT that will quickly change to black dot (phosphor burn which will be permanent)
can you take a picture of where you got that transistor from please.
or post the part position on the pcb it will have a number.tah.
because im pretty sure thats for the power supply,have a look on the opposite side next to the flyback its larger.
marked at part position 7512 its a BU508AF its clipped to a heatsink.(not bolted)
let us know when you have it.
Attachment 72519 < Here
- - - Updated - - -
Also, from a previous question, I still have 2 wires connected/soldered on this part. I don't know how to remove the black one which is going to the piece of plastic.
In a thread I read, the guy has cut it and soldered back with some tape.
Attachment 72520
wrong side bud, the other side of the flyback.the thing your looking at is the power supply.
just twist the black wire and pull it will come out eventually,dont cut it and dont ever cut a tape it together.
IE: twist,pull,twist,pull it will come out it just takes a while. to put it back it just push it in.
check post #18
ok I have removed the one on the other side (D1577), tested, and it is ok.
did you test all three pins? and reversed the probes?
and had zero reading on all pins?
Ok thanks Roy, I have successfully removed the wire :)
Also, I have ordered the new Flyback (70€, but this monitor is so good that if it can work again, I will be very happy).
it will work again bud
when you replace the flyback replace the hot as well,there cheap enough.
Where can I purchase it ?
here you go bud.
http://www.ebay.co.uk/itm/BU508AF-Tr...item43b1a598f3
Is it a replacement for the D1577 ?
its the part thats in the service manual and i use them,so yes mate.
they are both the same part mate,the D1577 is the equivalent of the BU805AF so dont worry.
EDIT: its also a good idea to put thermal grease on the back of this when you replace the clip on the heatsink,you can do this before you solder it.its easier that way to install it.(you can use ordinary white paste,its not all that important what type it is.its just to transfer it to the heatsink)but dont forget to put it on.
(also put thermal paste from the transistor off the power supply you where testing mate,dont forget its important)
if you happen to get one with a metal case,be careful and install a piece if insulation in between the transistor and the heatsink.this is because the metal ones have the collector on the case as well as pin 2.
but only if its a metal case transistor,the insulation is obviously not needed on the plastic ones.
this piece of info is only for everyone else who happens to be reading this as the link is for the plastic one.
Why do I need to replace it if I have tested it working today ?
Therefore I have added thermal grease before soldered it :)
do you mean the one off the power supply or the hot?
if its the power supply transistor bud,i meant replace the thermal paste the transistor dont normally go wrong there, besides i already know its working if it was not working there would no sound at all coming from the monitor faulty or not.
hope that helps.
When you told me today that I haven't tested the good one, I have jumped on the board, desoldered the good one and tested it. Tested with my multimeter (diode tester) and it (D1577) seems to work perfectly :) [post #21]
Everything is helpful :)
They sent me the 'right' flyback today. I hope to bring a good news soon :)
hi gibs
what was the result of the test on the D1577?
by that i mean the readings from your multimeter in diode test?
C e = 0
e c = 0
b c = 1
b e = 1
c b = 0
e b = 0
hi,it is micheal gibs isent it?
anyway,by the test a 0=nothing and 1=beep? or a reading of some sort?
if so,you might need to replace that part.(unless it is what it is below)
with the com of the meter on pin 2 and the other on pin 1 and com on pin 3 and the other on pin 1 after you should be getting somewhere between 450 and 500 ohms(not a beep) all others should be 0 in any configuration.
(but i have a feeling that is what you meant)
if your wondering,i dont trust that transistor after a flyback failure,working or not.thats why i change them.
i have had them fail after replacing the flyback/lopt.
Yes (Michael Gibs),
For "0", I wanted to say "infinite" and for "1" there were some values (not a beep) ...
Ok, so I'm going to purchase one very quickly :)
Thanks
Update: New Flyback received, PIN 11 missing !!! :( :( :(
http://www.donberg.ie/catalogue/line...s/hr_7533.html
:)
its ok bud,just install it...
It is useless ? It seems it is a ground...
mate,its ok.
just install it:)
http://youtu.be/BlFdWgcpwgE
Attachment 72720
Hey Roy, what is going on this pin close to the flyback ?
There are 2 black wire that are on the tube, I put one in the center of the motherboard and the second one in the back of the tube.
Still not working but the result is better. the sound has changed :
http://youtu.be/BlFdWgcpwgE
The screen flash and there is an acceleration... hmm
I have the LED in front of the screen.
At this point, I haven't changed the transistor. (not received)
i think you wired it up wrong mate...
turn it off and wait till the morning and i'll take pictures of where the wires go.
discharge the screen, in the meantime take a few pictures of the places where you put all the wires.including the neck pcb.
by the way the video is private...
EDIT: be very careful mate,its dangerous in the back of these sets if you dont know what your doing.im very worried.
and WAIT for the transistor to turn up and change it please for god sake.
If I don't answer anymore, then I am dead :)
Ok I have no doubt about the wiring now.
Don't worry I am very careful, if I don't know, I ask.
The video is public mate, thanks for your help again.
ok,wait for the transistor to turn up and change it...
and follow the instructions i sent via pm.
while your doing it make sure there is a signal input to the monitor to set it up,use an amiga or c64 etc for a picture.
i'll wait for you to do that.
the two wires on the back of the screen here.
http://www.amibay.com/attachment.php...3&d=1405581751
one goes to the neck pcb the other goes here.
http://www.amibay.com/attachment.php...4&d=1405581751
check this cable is connected,where im pointing with a screwdriver...
http://www.amibay.com/attachment.php...5&d=1405581751
discharge the screen and check that the ht lead from the flyback is securely fitted..
make sure the other two wires from the flyback are securely fitted to the neck pcb(the red one is soldered on and the black one cant be pulled out)
then change the the hot transistor.(ive probably said this a bizzillion times)
then after you change the transistor power it on and gradually turn up the screen pot(make sure you have a computer connected so you have a picture to work with...
if the set starts making noises,check where the noise is coming from..this is where its difficult to help without it being right in front of me.
but i'll try.and again.make sure ALL the cables are connected(deguass as well,it goes from the very front of the screen to the very rear of the set near the power input iec connector)),but you dont have to connect the sound up it will work without it.
Waiting for the transistor, I thought it was the right time to check component around the flyback.
A week ago I have tested the capacitors : 2445,2451,2447,2446,2452. All were returning good values.
Tonight I have added to the list : 2524,2541,2422,2547,2537,2520,2536,2526
Then I moved to Resistors : 3420,3422,3425,3426,3427,3428,3513,3514,3515,3526,3274
and finally I found one with a bad value: 3271 should be 1.5Mohm 5% the value returned unsoldered is : 1.126Mohms should be 1.425 Mohms
a difference of : 299 ohms.
This resistor is close to the flyback. I don't know where it is in the schematics because the scan is horrible :)
Somebody own a good scan of the 1084S-P1 service manual ?
Thanks
3271 connected to the BU508AF?, 1M 5% 0,5W i think.
you could test the diodes if you like.
Attachment 72754
In the service manual : 3271 = 1M5 5% 0.5W
Diodes tested : 6440,6441, 6443,6444 and many more but as I didn't wrote them, I'm good to test them again :)
Which one are you thinking about ? thx
6510,6513,6517,6518
when your done there can you check all the resistors,diodes and capacitors around the area that i was pointing to with a screwdriver.(especially the capacitors..)
anything around the TDA3505(to the left of the screwdriver),i think you could probably work out why...due to the way it failed.
i would be looking there after a lopt replacement.
here you go bud,its 1M i checked the parts list as well.
are you having a bit of a look in the power supply area?
http://www.amibay.com/attachment.php...2&d=1405633630
EDIT: ive got two service manuals here and that part has two different ratings in both(exact same chassis)...i suggest reading the bands on the part and decoding them if you can read the colours..
Hello Roy,
Can you post your schematics please ? Seems better quality that the one I have.
Thanks
im could not upload it here..
i will upload it on eab mate,you are still a member there arnt you?
there in the zone on eab.