Monitor Help needed please

[Brookesy]

Hello, Firstly let me introduce myself. My name is Gavin, i live in the UK and have recently been lurking around these parts recently. I decided to build my own mame bartop/mini through much reading of old topics which are very comprhensive and have solved many of my problems. Heres hoping i can get some help and maybe others too.

I came across an old cabaret machine in the classifieds and decided to buy it rather than build my own [project for another time] I want to utilise the monitor if possible for a mame conversion fo this cab, the cab is non-jamma its wired to a 22pinout think was galaxian but has no game in currently.

Monitor info - Vertically mounted Hitachi 19inch,  on the hitatchi sticker it has a - number type which is 37ECB22-TC10 and a - serial number M  9C8S3165 and on the main board there is sticker with this C14HC. I have added some pictures can add more if needed.

My problem is i dont know if this monitor is working/capable of repair? Anyway when i plug it in should the screen light up or display a blue/black sort of start up screen? or does it need a video in attached in form of PCB or breakout VGA cable before it will display anything? When connected to power supply i can hear the hum of high voltage going through it and near the neckboard area can hear a very indistinct sort of crackle noise cant really describe it but nothing displays on the monitor.

[speedklz]

It will not display anything unless hooked up to a pcb or a breakout monitor cable attached to something. Please be carefull with it if you have had it hooked up to power, I cant stress this enough it can kill you....

[Brookesy]

Thanks speed, i have done lots of reading in this area and fully understand the hazards involved. Would i need a video amp or the ultimarc vga card or would my monitor be able to accpet the picture without? if a bit dim? As i want to establish if the monitor is working dont wanna have to fork out for the ultimarc card to find out my monitor doesnt work. Thanks Again.

[grantspain]

locate the screen volts on the flyback transformer(we call it lopt or lopti in u.k),turn on cab and power to monitor then turn screen volts a little clockwise-if you get a white screen then it works

[Brookesy]

Thanks grant im pretty sure i know what your referring to but before i get ahead of myself can you check the pictures to ensure i was right? Thanks.

[grantspain]

none of them,look at the back of the crt and you will see a thick red wire going from about 3/4 up centre that goes to a large black plastic component on the chassis-this is the lopt,here you will find focus and screen volts control

[Brookesy]

The only component that looks like your descrption is the one above img.1223 this is a better picture of it has focus on bigger one and screen on smaller one heres is a better of pic of them

[grantspain]

thats one ancient monitor you have there,the screen volts is to the left of the focus pot on that photo

[Brookesy]

Yes it is, also very grubby. Its the orginal one that was in the cab 1987, I tried adjusting it but no change in the monitor display whatsoever looks the same off as it does on. which im guessing is not a good sign. lol. Anything you would reccomend to find out if its fixable or not?

[grantspain]

before going further there are 3 others checks to make,
see if there is an orange glow from neck of the crt
check for static on the crt or a flash when powered off
meter the ac voltage input to the monitor,should be around 110-120vac

[Brookesy]

There is an Orange Glow from the neck of CRT when powered up but no static/flash on the display after powered down. I haven`t got a meter to hand but my friend has one so will borrow it when he has finished work in hour or so to check that.

[grantspain]

ok orange glow is a very good sign,it means the tube heaters are running which basically means the monitor is working.
next step is to get a video source on the cab-although the lack of ht is worrying,but that could be down to a bad solder joint on the flyback

[Brookesy]

Okay, so with regards to a video source from reading i know some monitors have issues if you connect them to a pc with just a breakout cable [no video amp or a vga arcade graphics card from ultimarc]. Would i be able to get an idea of what the picture would be like and if colours/picture is working fine with just a breakout cable or will i have to just invest in the ultimarc card + breakout cable and hook it all up and see?

[grantspain]

you have to make sure that you feed this monitor with a 15khz signal,if you have a compatible graphics card i think you can use soft 15khz(info at top of monitor section)
if you feed this monitor with 31khz then at best it won't work and at worst you will blow the horizontal deflection transistor

[Brookesy]

Thanks Grant for taking the time to answer my questions and help really appreciate it, time to do some reading on soft 15khz next for me i feel then will take it from there. Cheers.