Hantarex Polo Color problem....

[MacStone]

Hi all,


I recently ( 2 months ) purchased a fully functional cabinet with a 25" Hantarex Polo.
I only been using it for a month or so but here is where the problem starts.
While playing Mortal Kombat, the screen suddenly went Blue&White and it's been like that ever since.
I haven't tried anything yet because i have no idea what it could be.
There was a power unit in the bottom of the cabinet, which i believed provided power to the Jamma board and therefor have removed right from the start.

My current setup is:

J-Pac
GeForce2 GTS
Powerstrip

Apart from the obvious question, "what could it be & is it fixable",
i was also wondering if (in case it is dead):

1) Could the Power unit have something to do with this?
2) Will the support Frame support a bigger screen? e.g. 28" or 33" since there seems to be a lot of space left in the cabinet?
3) Are all the Support frames the same or do i need to drill more holes in the cabinet?
4) Has anybody ever used the NVidia Timming Tools (Comes included with drivers) successfully with an Arcade monitor before?

Thank's for your help

[grantspain]

can't tell your photo whether your blue transistor has gone short full on(thus enveloping the other colours)or red and green are missing.start with the obvious,check for bad solder joints on the neck card(especially around the colour drive transistors)-here's a tip ,you can tap the neck card gently to prove whether it is bad solder joint.then compare the readings of the transistors with a meter to prove any failure.if no luck with this we can look at the other usual hantarex problems.

[MacStone]

Thank's for the quick responce.
I'm not very familiar with the electronics part of monitors.
1) Do i need to discharge the monitor to do this? ( i don't want to blow myself to kingdom come..  )
2) where exactly would i find the colour drive transistors?

[grantspain]

you don't have to discharge the monitor to do these checks,just make sure its switched off.
the colour drive transistors are situated on the neck card(the square board with the big polo text on) which is on the end of the tube itself.
first remove the plastic cover from the neck card,its held on the card by two pieces that push through holes each side of the card.
then you look,using a flashlight for the bad solder joints(they will be easy to see as you will notice cracks around the componant legs,lets take it from there

[MacStone]

Right,

I had a look at the neck card but i cant seem to find anything wrong with it.
Any ideas would be appreciated.

Cheers

[grantspain]

really difficult to see from the photo but there is some heat related issue on the transistors(they are on the bottom right/3 in a row),have you tried tapping the neck card to see if the colours change at all.is this a mame cab or standard arcade???
that first picture you posted is kung fu master???

[MacStone]

Sorry for the initial lack of information.
It is a Mame cab and you are correct ( Kung Fu Master ).
The error first occurred while playing mortal Kombat.
Tapping it didn't do anything. ( no change to the colours ).
To test the transistors, will a multimeter do the trick?

Cheers

[Kevin Mullins]

Yes, you can test these with a multimeter.
http://www.anatekcorp.com/qdmmvom.htm
or
http://www.elexp.com/t_test.htm
(if all that makes any sense)

Do a "wiggle" test on the video signal leads as well. ( J106 )
Looks like it is the second plug from the left in your monitor back pic.
Might be a bad connection or bad solder joint there.

Double check your breakout cable from the PC that should be going to that same plug also.

[grantspain]

i know sweet f.a about mame stuff but is your graphics card all o.k,its just i had a wartran that lost both red and blue and that was a graphics card fault-if not then its either your blue cut off pot or blue drive transistor faulty(or the red and green signal missing)

[MacStone]

I've tested the connection from jamma interface to J106 and it seems fine.
J-Pac says OK. Sync correct and tested VGA breakout lead.
Also tested GFX card (GeForce2 GTS). I had a GeForce4 MX in it before and have the same result.
I am at a loss with this one...

I will have a go with the multimeter and see what i can find.
I just hope i wont electrocute myself in the process...

Cheers

[Kevin Mullins]

i know sweet f.a about mame stuff

He, he... me either. I just run the basic run of the mill Windows Mame (Mame32) on my PC.

Defineately sounds like a monitor issue like grantspain is talking about.

Is the screen blue-ish if you disconnect the video/breakout cable completely?

[grantspain]

good call on disconnecting the rgb input kevin,that will prove if the blue transistor is skying it

[scumball]

You may want to check out my thread on a pretty similar subject....

http://forum.arcadecontrols.com/index.php?topic=53550.0

Got some great advice and brought the monitor back from the brink...

Also I'd put that power transformer back in if I were you - I have a Hantarex US250 isolating transformer that powers my Hantarex Polo monitor - apparently it's pretty dangerous to remove these - can make the cabinet live or something...

Also the Polo should discharge itself, so it's not quite as lethal as some monitors, but I'd still steer clear of touching the big sucker thing on the back (LOPT?) or anywhere around it.

[MacStone]

Also I'd put that power transformer back in if I were you - I have a Hantarex US250 isolating transformer that powers my Hantarex Polo monitor - apparently it's pretty dangerous to remove these - can make the cabinet live or something...

There was a Power Supply (a Phillips unit) which i assumed was for the Jamma board only....    was i wrong?
I'll try and post some pic once i get back tonight.

Also the Polo should discharge itself, so it's not quite as lethal as some monitors, but I'd still steer clear of touching the big sucker thing on the back (LOPT?) or anywhere around it.

Didn't know that polo monitors do that...  are you sure?
Hopefully i get to do some testing tonight.

Cheers

[Kevin Mullins]

There is a difference between "power supply" and an "power transformer" (isolation transformer).
Read through Bob's write-up:http://homearcade.org/BBBB/acwiring.html

Power Supply - the +5, -5, +12, Gorund, etc (in your case the jamma harness power)

Isolation Transformer - usually a small silver or goldish metal box with two coils stuffed inside it and only two lines in and two lines out. The only thing hooked to it's output should be the monitor AC power leads.
(don't confuse that with the tiny EMI filter either)

Let us know how the troubleshooting stuff that we've already mentioned goes.

[MacStone]

Only just got home...       Traffic.......
240 miles to work & back...... it's a killer 
I re-tested the connection between the Jamma board & the monitor RGB connector just to make sure.  .
I get a clear signal no problems. also managed to double check the neck board for bad solder joints, again OK.
Just need to do some measuring now. I did have a glimpse with a mirror though, to visually check the components but apart from a lot of dust, it looks alright.
could do with a cleaning...
Now for some food and rest... (5am start tomorrow)    Will let you guy's know.

Cheers

[scumball]

There is a difference between "power supply" and an "power transformer" (isolation transformer).
Read through Bob's write-up:http://homearcade.org/BBBB/acwiring.html

Power Supply - the +5, -5, +12, Gorund, etc (in your case the jamma harness power)

 I think the Hantarex is all in one...mines 240v in, 128v out for monitor and +5, -5, +12 etc...

[grantspain]

i don't think you should worry about the power issue,hantarex made a psu which incorperated monitor and low voltage outputs,as long as your monitor runs from an isolation transformer and is earthed then thats fine.like mentioned dis the signal plug and see if your screen is still blue

[MacStone]

like mentioned dis the signal plug and see if your screen is still blue

Done that but all i get is a black screen.

[grantspain]

you need to prove the input signals are correct,is there any way of getting a different signal input onto your monitor??

[Kevin Mullins]

Now disconnect JUST the blue signal......actually pull it out of the connector.... and see if it only shows just black still or if the red and green show at all.

If they don't show at all:
While you have the blue signal wire out all by itself, briefly touch it to the red or green signal inputs one at a time and see if either of those colors show up then.

If they do - bad signals from board.
If they don't - still got a monitor problem, time to start checking transistors and pots.

And you can do it vice-versa as well, take the red or green signal and apply it to the blue to see if the red and green signal is at least there. (it will show as blue though)


Note: I was just trying to clarify ealier that a typical power supply and an isolation transformer are two different beasts and do two totally different functions. That's all.

[MacStone]

Now disconnect JUST the blue signal......actually pull it out of the connector.... and see if it only shows just black still or if the red and green show at all.

If they don't show at all:
While you have the blue signal wire out all by itself, briefly touch it to the red or green signal inputs one at a time and see if either of those colors show up then.

If they do - bad signals from board.
If they don't - still got a monitor problem, time to start checking transistors and pots.

And you can do it vice-versa as well, take the red or green signal and apply it to the blue to see if the red and green signal is at least there. (it will show as blue though)

I was hoping to try that tonight, but I'm to knackered to even type...
Hopefully i get off work early tommorrow and give it a shot.

Note: I was just trying to clarify earlier that a typical power supply and an isolation transformer are two different beasts and do two totally different functions. That's all.

Yes, thanks for that. It's a bit of confusing issue for me since i don't understand much about electronics. 

[MacStone]

Now disconnect JUST the blue signal......actually pull it out of the connector.... and see if it only shows just black still or if the red and green show at all.

Test: Failed. Black screen.   

If they don't show at all:
While you have the blue signal wire out all by itself, briefly touch it to the red or green signal inputs one at a time and see if either of those colors show up then.

Test: Failed. Again just black screen.   

And you can do it vice-versa as well, take the red or green signal and apply it to the blue to see if the red and green signal is at least there. (it will show as blue though)

Test: OK. I get Blues...   

If they do - bad signals from board.
If they don't - still got a monitor problem, time to start checking transistors and pots.

Right.

1) What exactly do i need to check now and where is it located ?

2) Does the Monitor need to be powered off ? (I hope so)   

3) Multimeter is still the tool of choice i take it ? 

Tank you guys for the help 

Cheers

[grantspain]

that proves your signal in is o.k,now you have to meter your transistors-also there is a colour decoder ic on the neck card (lm1308n i think),it could be that
a quick thing you could do is swap the red and blue drive transistor,that will prove whether the fault lies there,also check continuity on the wires from the main chassis

[MacStone]

Can the neck card be removed ?

[grantspain]

yes of course,with the monitor switched off you need to grasp each side  of the card,pull gently backwards whilst very slightly moving it left to right(and vice versa)-remember when replacing this card goes on one way only,its easy to do as it has a location point and it goes on square

[grantspain]

hey i have just seen you are in the u.k,where abouts are you?

[MacStone]

I'm in Leicester.   

[grantspain]

if you get stuck there must be loads of amusements operators near you e.g gamestec,leisure link,crown.
if you need parts you can get them from www.cpc.co.uk,or you can contact hantarex in london(www.hantarex.co.uk)
bloody hell 240 miles to work and back,do you work in london?
anyway i am convinced the problem is on the neck card

[MacStone]

bloody hell 240 miles to work and back,do you work in London?

It's liverpool actually..   

I did some tests but it's hard if you don't know what to look for exactly.
I've circled the ones i could not get any reading of.
Also what kind of reading am i looking for ?

[grantspain]

completly the wrong area,you should be looking at the three transistors with the heat sinks on for a reading on the right of your picture,the chip i mentioned is the one with the red sticker on-try adjusting the pots first just in case its bad setup

[MacStone]

completely the wrong area,you should be looking at the three transistors with the heat sinks on for a reading on the right of your picture

Those Transistors read as follows:
6.74
6.76 (middle)
6.74

I also measured the RGB Cut offs & Gain. (don't know if it matters)
Red Cut off    - 031
green Cut off - 032
Blue Cut off   - 032

Red Gain  - 053
Blue Gain - 055
Green doesn't exist..   

the chip i mentioned is the one with the red sticker on-try adjusting the pots first just in case its bad setup

How do you test that chip?

[grantspain]

how are you reading the transistors exactly?
the chip is not simple to read,really you need an oscilloscope and a breakdown of the ic operation.
you see the big problem with the fault you describe is the fact you have lost two colours,not just one.if it were a case of one colour missing you could narrow it down to transistor,resistor,signal missing or broken track but two colours is more likely to be colour decoder ic(the one i mentioned),signal output of the game board (it has to be common to the two colours)
if this were a fault i had in front of me now i would do the following;
1-check continuity of signal wires from game board output to input on the monitor chassis
2-prove signal input by swapping r g b around
3-prove continuity of cable from neck card to main monitor chassis
4-meter and compare readings of drive transistors and feed resistors(when reading transistors and you have two or more the same always compare readings e.g with your meter on ohms read from each leg one at a time,the legs for arguments sake are numbered 1,2 and 3 you have to start with your positive probe on 1 and put negative to 2,write the reading,then put the negative to 3 and write the reading.
so you read like this 1(2 and 3),2(1 and 3),3(1 and 2) now reverse the probe leads and read again,hopefully every reading will be the same on each transistor.
5-double check that the blue is not adjusted too high by adjusting all the colour pots
6-check all the pins are straight on the tube neck
7-double check for any broken track or dry joints(sometimes you can get a very fine crack that is nearly impossible to see)
8-if all the above checked out perfect i would change the decoder ic(for me its a 2 min job and the ic is about a couple of quid to buy)

[MacStone]

how are you reading the transistors exactly?

Kevin Mullins posted a couple of links which i followed.
http://www.elexp.com/t_test.htm

1-check continuity of signal wires from game board output to input on the monitor chassis

Done that. Since i don't have a game board, i tested it from the J-Pac.

2-prove signal input by swapping r g b around

Done that. All i get is Blue.

3-prove continuity of cable from neck card to main monitor chassis

Not tried that yet. Do you mean the RIBBON cable?

4-meter and compare readings of drive transistors and feed resistors(when reading transistors and you have two or more the same always compare readings e.g with your meter on ohms read from each leg one at a time,the legs for arguments sake are numbered 1,2 and 3 you have to start with your positive probe on 1 and put negative to 2,write the reading,then put the negative to 3 and write the reading.
so you read like this 1(2 and 3),2(1 and 3),3(1 and 2) now reverse the probe leads and read again,hopefully every reading will be the same on each transistor.

Transistors give back same reading.

5-double check that the blue is not adjusted too high by adjusting all the colour pots

Goes either completely blue or completely black (no picture).

6-check all the pins are straight on the tube neck

Checked.

7-double check for any broken track or dry joints(sometimes you can get a very fine crack that is nearly impossible to see)

Checked. No dry joints but I'll double check for cracks.

8-if all the above checked out perfect i would change the decoder ic(for me its a 2 min job and the ic is about a couple of quid to buy)

That seems the logical (easier) way to go. Where can i get/order it from?

Thanks for all the help   

[grantspain]

yes ribbon cable
you should be able to get it from your local maplins(if they don't have they can order it for you).
tomorrow i am gonna look at one of my polo chassis just to see if there any other common components
well done so far btw

[grantspain]

i checked out my circiut diagram and neck board today,the chip number is lm1203n,not what i last said-it does seem to be the only common component to all colours,the r g b signal comes on the ribbon cable at position 6,7 and 8 then through caps c1,c2 and c3 then into the chip

[MacStone]

Hey guy's,

1 week away from home...... 
RS apparently have the chip in stock, so I'm ordering it tommorrow.
Tonight i have a big date....  me and a soldering iron 
Ill let you know how it goes.

Cheers

[grantspain]

cut each leg off the ic first using high quality precision side cutters,then remove each leg one by one,then desolder the holes otherwise you may damage the circuit board-also remember where those caps go

[MacStone]

Managed to do something today.
I removed the neck card so it will be easier to remove the IC Chip.

i checked out my circuit diagram and neck board today,the chip number is lm1203n

The IC Chip on mine seems to be different. It says "TFK U2203B".
Is the LM1203N interchangeable with this one?

I hope so because I've already ordered 2 units. (1 for spare)

[grantspain]

don't worry all mine are lm1203n,your chip must be a generic replacement
mind you i would not have removed the neck card completely like you have,but if it makes it easier for you then no worries,just remember that chip only goes in one way also don't add those little caps which were on your first chip soldered on the solder side(i have a feeling they are used because that chip is a generic)

[Kevin Mullins]

They are a pretty darn close matchup to eachother.   Go for it !!

LM1203N :
http://pdf1.alldatasheet.com/datasheet-pdf/view/8607/NSC/LM1203N.html

U2203B :
http://www.ortodoxism.ro/datasheets/Temic/mXyzutqw.pdf

[Safan]

OK i have a similar thingy after cleaning up my cabinet and putting the wrong plugs into each other 
A had no blue color, just green & red ...
Switched RGB pin an the jamma plug (soldered), so my blue does work!
So i take a look on the scheme, the good thing is that the 3 colors circuits are identical so you can compare to each other!
Take a look at the electronic board at the back on the tube, swapped the rgb's like i did on the jamma plus and the colors are all working just one missing wile swapping.
Built out my chassis measured all components of that circuit, i had a broken zenerdiode!
Changed also capacitors & transistors as i was afraid of damage after connecting the wrong plug .....
And it works! Lucky me 
Oh i have a hantarex mct9110 monitor, but i presume it's much the same ....

[MacStone]

Hi guys,

I'm sorry for the lack off updates on this but i have been very, very busy. 

It's been 3 months since I've came here with my monitor problem, and i finally got it to work with the help of all of you. 

Hopefully i will get some screenshoots once i finish installing the software.
In the meantime, here is a pic of the neck card with the new chip installed. 

Cheers,
Mac

[grantspain]

thats good news,was the problem the Lm decoder i/c in the end or other

[MacStone]

Yes, it was the IC chip.
I've managed to solder a socket onto the board, to facilitate the chip's removal.   
Now i keep one spare just in case.

[grantspain]

well congratulations and it looks a pretty professional job as well,sockets are always handy.now we just wait to see perfect screen shots

[Bunnyuk]

Hi guys,
Where can I purchase  these transistors for the neck board, and capacitors?

Thanks