Main Restorations Software Audio/Jukebox/MP3 Everything Else Buy/Sell/Trade
Project Announcements Monitor/Video GroovyMAME Merit/JVL Touchscreen Meet Up Retail Vendors
Driving & Racing Woodworking Software Support Forums Consoles Project Arcade Reviews
Automated Projects Artwork Frontend Support Forums Pinball Forum Discussion Old Boards
Raspberry Pi & Dev Board controls.dat Linux Miscellaneous Arcade Wiki Discussion Old Archives
Lightguns Arcade1Up Try the site in https mode Site News

Unread posts | New Replies | Recent posts | Rules | Chatroom | Wiki | File Repository | RSS | Submit news

  

Author Topic: Help and advice to test a Wells Gardner K7689  (Read 4860 times)

0 Members and 1 Guest are viewing this topic.

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Help and advice to test a Wells Gardner K7689
« on: April 26, 2016, 04:29:05 pm »
Hey guys, I sourced this monitor some 5 years ago and for one reason or another, simply haven't got round to building my mame cabinet project. I'm now making a concerted effort to do so and the time has come to test and install the monitor.



I'm looking for some information on how I would go about testing the monitor works, prior to installing in the cabinet. I have no experience with monitors' and I'm well aware how dangerous they can be. The attached photos show the model number and the board. I've watched a few videos about how to discharge them, particularly this one

and will do so before attempting to eventually power on the monitor.

I've 2 specific questions I'd like to ask.

1) What's the easiest and cheapest method to test the monitor actually works? I'll eventually be getting an arcadevga card. Right now though I don't have anything to actually plug into the data plugs. What could I use/buy to test the monitor's picture? Preferably fairly cheaply.

2) I'm in the UK, what should I use to connect to the monitor's power plug? Do I need some form of transformer? Plus some sort of adaptor for the plug itself? The FAQ mentions an isolation transformer? Where would I get one of these?

Hope you can help, thanks guys.

obcd

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 160
  • Last login:April 03, 2019, 11:44:36 am
  • I want to build my own arcade controls!
Re: Help and advice to test a Wells Gardner K7689
« Reply #1 on: April 27, 2016, 03:55:34 am »
Discharging is only needed when you separate the pcb from the picture tube.
The Tube can hold it's anode voltage (several thousands of volts) hours after the chassis was switched off.
For that reason, the tube is discharged before the anode cap is taken off. There is no reason to do it before you turn on the monitor.

As your monitor is a 120V model, it's almost certain that it needs an isolation transformer. It should be capable of transferring at least  85W.
So, basically, it's a transformer from 240V to 110V (maybe 120V). Where to find them is difficult to say, as the question should be where can I find a cheap one. They where present in pretty much all older cabinets. Every respective electronic component store should sell such transformers as well. I assume you might find it on Ebay as well, but they are heavy components, so the shipping costs could be high.

A first monitor test is simply powering it with no video signal connected. You should hear the Anode voltage come up, and you should feel some static electricity on the front of the picture tube. (A piece of paper might stick to the front surface.) If you turn up the screen potmeter (usually on the back of the LOPT), the picture tube should show a grayish / white surface. If those things all happen, your monitor should show an image when a proper video signal is connected. How pure that image will be depends upon a lot of conditions, like the number of burning hours the tube has already. A wise thing to consider is a so called capkit. This basically means replacing all the electrolitic capacitors on the chassis board, as those tend to age and dry out, decreasing picture quality. Don't forget to turn the screen voltage down again after the test, as your image can be 2 bright and have some crossing lines in it if the screen voltage is set 2 high.

lilshawn

  • Trade Count: (+3)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 7363
  • Last login:Today at 01:05:20 am
  • I break stuff...then fix it...sometimes
Re: Help and advice to test a Wells Gardner K7689
« Reply #2 on: April 27, 2016, 11:44:31 am »
good job, I read through your post OBCD and found everything mentioned that I would have mentioned myself.  :cheers:

can confirm, this chassis needs to be isolated from mains. it uses a regulator circuit that is damaged by hooking directly to mains. newer style "switchmode" type monitor chassis don't need isolation.

I can't confirm however... the voltage it requires. it could be a UK only model. it's chassis very similar to the k7000 series which requires 110v, but I know some of the regulators used on some of the later K7000's use a different regulator that actually take the 110v input and bump it up to 220 volts internally using a voltage doubler circuit... this circuit is bypassed when voltage is 220. so it may not need a 220 to 110v transformer. but again, i can't confirm.

What is the regulator it has? it should be a STR30130 or 30123 or something similar to that. it'll be attached to the heatsink next to the big white ceramic resistor mounted to the corner.   maybe they've modded it to work on 240 volts.

If you have a cabinet, it may have a transformer in it already. take a look...it won't be huge or anything (about 5CM square)

If you don't have a cabinet, consider talking with some arcade game operators or route operators, you may be able to score one for cheap or free. find a random coin operated game in a pub/mall/arcade and ask who supplies the game to them. call them up and ask. it can't hurt. if not them, ask if they know who would. We gladly give away some stuff just so we don't have to throw it out.

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #3 on: April 27, 2016, 06:20:12 pm »
Thanks so much for the info guys, it's much appreciated. :)

I've read a bit about replacing the chassis's caps and also its flyback. I'm certainly up for doing it but unfortunately I'm at a loss at where to purchase them from? From what I can gather, the real Bob Roberts is the recommended place, but it seems he doesn't ship internationally anymore. :( I'm looking into whether any US based friends would be willing to place an order and then ship the parts on to me. In the meantime tho, can anyone suggest a reputable alternative?

lilshawn, could you give me a bit more info on what the regulator looks like? Is it part of the chassis board or somewhere else? I can provide further photos if it would be of help.

In the event of me lucking out and needing a transformer :( I've been looking at places and things look a little expensive. Espcially since I'm not exactly sure of all the ins and outs of what I'm needing. I found this place however, which seems to sell quite a range
http://uk.farnell.com/
again tho I'm not entirly sure what exactly I should be looking at. Would someone knowledgable be so kind as to check the link and point me in the direction of the exact isolation transformer I'd be needing?

Lastly, and apologies if this sounds really dumb! Could someone tell me what this 2 pin connector's technical name is?



I know (I hope!) it's the power plug but I presume I'll need some sort of adaptor for it to connect to whatever transformer I get.  I haven't a clue what it's actually called, a 2 pin molex plug perhaps?

Thanks again guys.

Edit: I forgot to add, the monitor is going in a brand new kit cocktail cab so no transformer already in situ unfortunately.
« Last Edit: April 27, 2016, 06:27:05 pm by gizmo1990 »

lilshawn

  • Trade Count: (+3)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 7363
  • Last login:Today at 01:05:20 am
  • I break stuff...then fix it...sometimes
Re: Help and advice to test a Wells Gardner K7689
« Reply #4 on: April 28, 2016, 01:00:52 pm »
The caps should probably be replaced...the flyback......unless it's damaged or cracked and ozzing...i wouldn't worry too much about it....when they fail, they usually do so quite spectacularly and make it fairly obvious.

i'm not sure about the plug, i'd have to see the end of it. where does it go? is it just for the power? if so, you can wire on whatever plug you want provided it is capable of supplying enough voltage/currant.

someone on another forum in the UK with a similar situation purchased this:
http://uk.farnell.com/schneider-electric/abl6ts02g/transformer-25va-1-x-115v/dp/2070175

the regulator is the item being held down by these 2 screws i've circled:

« Last Edit: April 28, 2016, 01:05:28 pm by lilshawn »

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #5 on: April 29, 2016, 02:05:26 pm »
Thanks again for that lilshawn.

I've found the regulator, it's a STR3123. I'm guessing that means it probably isn't modded? Thanks for the transformer link I'd actually been quoted another transformer by that company too. This one http://uk.farnell.com/block/sat200/transformer-auto-200va-uk/dp/1131563, it looks pretty decent. :)



I'm looking into obtaining a cap kit and a new flyback just in case. I figure that if I go to all the trouble of replacing the caps it might be as well to do the flyback as well?

Here's some close-up shots of the power plug. It looks like a molex type plug to me. Anyone know for sure?

« Last Edit: April 29, 2016, 02:14:05 pm by gizmo1990 »

lilshawn

  • Trade Count: (+3)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 7363
  • Last login:Today at 01:05:20 am
  • I break stuff...then fix it...sometimes
Re: Help and advice to test a Wells Gardner K7689
« Reply #6 on: April 29, 2016, 02:50:20 pm »
the transformer you quoted does not isolate the mains....it says so on the first page of the datasheet.

it must must isolate the output from the input. That one does not... it converts the voltage...but does not isolate.

I will try and find a part number for the plug for you.


EDIT

42179-2R1
or
0003121026
HCS-125 series

confirm dimensions with the drawing here:

http://www.molex.com/pdm_docs/sd/003121026_sd.pdf
« Last Edit: April 29, 2016, 02:56:18 pm by lilshawn »

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #7 on: April 30, 2016, 10:33:23 am »
Thanks for that lilshawn. Yep someone at the electrical website also set me straight on that fact. Phew, it's complicated stuff getting this monitor up and running!

I've now been pointed in the direction of this transformer: http://uk.farnell.com/block/tim100/transformer-isolating-2-x-115v/dp/1131597 Apparently it I'll need to connect the dual outputs in parallel but that shouldn't be too hard should it?

However there also seems to be some discussion on whether the power draw would be in excess of the 100W of this transformer? Apparently transformers can have 85% efficiency. Added to this, monitors can also have differences in power consumption which would mean that 140-160W would be more appropriate.

On the other hand the sticker on the chassis explicitly states 85W as a MAX. Which probably means peak power draw at on switch-on and not continuous. Therefore perhaps 100W should be fine? Obviously the price jumps a lot if I need a 200W version. Can anyone shine any more light on this point? Do these monitors' need transformers with higher rated W output than their quoted max?

Thanks again for that molex plug find, spot on! :)
« Last Edit: May 01, 2016, 06:36:36 pm by gizmo1990 »

obcd

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 160
  • Last login:April 03, 2019, 11:44:36 am
  • I want to build my own arcade controls!
Re: Help and advice to test a Wells Gardner K7689
« Reply #8 on: May 02, 2016, 04:47:40 pm »
It wouldn't suprise me that the monitor it's power consumption is around 85 Watt during normal operation. It will depend upon it's brillance settings, and showing a full white screen might increase it's power consumption. One way to find out is connecting a wattmeter. Problem is that you will need the transformer before you can measure the actual power consumption. A 200VA will be able to get rid of it's heat much easier. You might get away with the 100VA, but the surge current at powerup will likely be higher than the advertised 85 Watt, specially if there is an automatic degaussing circuit that also kicks in at powerup.

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #9 on: May 03, 2016, 05:14:06 pm »
Thanks for the advice obcd. I don't want to damage the monitor given how long it took me to source, nor spend money on a transformer which isn't up to the job. It looks like I'll have to put the build back on ice for a while till I can save my pennies for the 200W model.  :'(

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #10 on: July 20, 2018, 06:04:28 am »
Thread bump!! Well, I've saved my pennies and I intend to get the 200w transformer in the next month or so.  :) It's only taken me 2 years.. :dunno

I've already managed to get hold of a cap set and a flyback. Plus, I've also just got an old radeon 5450 which I'll be using to test the monitor eventually.

With this in mind, I'm now considering my plan of attack to fire this monitor up. Part of me is wondering whether I should test the monitor first before replacing its caps? I'm also wondering whether I need to install the flyback now or keep it in reserve? Are there any tests, visual inspection or electronically, which might suggest the best approach? Basically I'm looking for some advice on what my next steps should be. If anyone experienced in this could offer some good advice, I'd really appreciate it.

lilshawn

  • Trade Count: (+3)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 7363
  • Last login:Today at 01:05:20 am
  • I break stuff...then fix it...sometimes
Re: Help and advice to test a Wells Gardner K7689
« Reply #11 on: July 20, 2018, 03:29:07 pm »
everything on that chassis is going to be oooooold. it's best to change out the caps and stuff now, old dried out caps and overload regulators and transistors and blow them... then you are searching for (likely) discontinued CRT transistors and obsolete regulators and trying to match them up with something...which often doesn't go well.

Check around the adjustment knobs on the flyback for cracking...typically flybacks don't go bad...unless it's cracked or is oozing plastic out it's seams i'd leave it for now.

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #12 on: July 22, 2018, 03:46:19 am »
Thanks @lilshawn Righto new caps it is then! The board is extremely grimy with dust, which looked a little tacky rather than the clumpy dry kind. Perhaps the monitor resided in a fast food shop earlier in its life? Would you suggest cleaning it before the attempting the cap replacement? I’ll go gently with some anti static brushes first, but if that doesn’t shift the worst of it, would a cotton bud dipped in isopropyl be recommended? Or should I just leave the board as is?

behrmr

  • Trade Count: (+1)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 459
  • Last login:April 23, 2021, 09:17:13 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #13 on: July 22, 2018, 09:08:09 am »
Thanks @lilshawn Righto new caps it is then! The board is extremely grimy with dust, which looked a little tacky rather than the clumpy dry kind. Perhaps the monitor resided in a fast food shop earlier in its life? Would you suggest cleaning it before the attempting the cap replacement? I’ll go gently with some anti static brushes first, but if that doesn’t shift the worst of it, would a cotton bud dipped in isopropyl be recommended? Or should I just leave the board as is?

Wash with simple green or other household cleaner/degreaser and hot water in the sink. Allow to dry overnight on top of or in front of a fan. You can use a soft bristled paint brush to “scrub” the nasty areas. I wash everything before I cap it. You can do the same with the tube and frame once you remove the chassis (easier with chassis removed).

lilshawn

  • Trade Count: (+3)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 7363
  • Last login:Today at 01:05:20 am
  • I break stuff...then fix it...sometimes
Re: Help and advice to test a Wells Gardner K7689
« Reply #14 on: July 22, 2018, 07:05:29 pm »
don't wash the aquadag off the back of the tube...bad things will happen. BZZZT!

gizmo1990

  • Trade Count: (0)
  • Full Member
  • ***
  • Offline Offline
  • Posts: 41
  • Last login:November 27, 2021, 10:45:18 am
Re: Help and advice to test a Wells Gardner K7689
« Reply #15 on: July 23, 2018, 06:43:20 am »
Thanks guys. I will start to prep the cleaning process and report back. Likely with lots of photos asking to double check things before I proceed! ;)