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3 Editorial Page 3-Editorial Page 4-Let There Be Light An MLD backlight retrofit/repair guide Page 11- USB Tester That Displays Voltage and Current Page 12- Quick Repair-LG Inverter Page 14-Subscriptions and Back Issues Dear Friends of, We have a very nice contribution this month from Greg Agostino. I first met Greg at TechFest but many of you already know him from his participation in the Slot Tech Forum where he is known as Spozgar. Spozgar is a sort of Zoroastrian version of the Norse god Thor but maybe not such a nice guy (although Thor can be a real asshat when he wants to cause... Thor). You can google it yourself for further study if you re into that sort of thing. Mr. Agostino s epic contribution is on the subject of [my nemesis] the MLD (Multi-Level Display). Casinos simply MUST be self-sufficient when it comes to monitor repair. On a recent training mission, I had a chance to look at an inhouse service/repair program, written by the property s lead tech (I am working on getting him to sell/release it to the rest of the casino community as it is a really nice program). Among its myriad of features is its ability to track and graph failure history, sorted per machine or by sub-assembly. When you look at a bar graph of sub-assembly failures, there is a giant spike for failed monitors. This is not just a little spike, it almost doubles the next highest failure (power supplies, of course). The bar graph was sorted alphabetically from left to right. With M (for monitor) in the middle, the bar graph was obviously giving me the finger. Well FU too cause I m a technician and I can handle anything you throw at me, with a little help from my friends! Our friend (God?) Spozgar shows us exactly how to stripdown the MLD to its backlight assembly and replace the CCFLs and associated accoutrement with the new concave lens LED strips now available from Pacific Illumination through their distributor, MCM Electronics. Thanks, Greg. Really great contribution. This will help everyone. Randy Fromm Randy Fromm's Editor Randy Fromm Technical Writers Tom Baker, James Borg, Nathan Galloway, Chuck Lentine, Jerome Mayard, Pat Porath is published monthly by 401 W. Lexington #777 El Cajon, CA tel fax editor@slot-techs.com Visit the website at slot-techs.com SUBSCRIPTIONS Domestic (North America) 1 year - $ years - $ International 1 year - $ years - $ Subscribe online at slot-techs.com Copyright 2016 under the Universal Copyright Convention. All rights reserved. See you at the casino. Publisher-

4 Slot Tech Feature Article Let There Be Light A guide to converting 20 MLD or any direct CCFL back light LCD panels to modern LED replacements. By Greg Agostini (STF Handle: Spozgar) techs told me I couldn t do it, well I m here to say if there is a will there is a way. The IGT MLD monitor is a nifty bit of kit that is until it fails due to a $5.00 fan dying thus cooking one of the more expensive LCD panels inside the unit. The heat generated by the CCFL inverter and the CCFL tubes themselves are a huge cause of failures of this monitor. They are expensive to replace and require some temporal investment to work on. However there is light at the end of the tunnel. I was presented with a challenge, how to make the 20 IGT MLD monitor more reliable and less likely to slow cook itself to death. The answer was obvious, get rid of the CCFLs and inverter. LEDs were the logical choice however the intense light, even with a good diffuser would still create hot spots that were visible. So there had to be a way, and after many fellow For about a month I did research into LED technology and using contacts overseas, I ordered up a mess of different LED technology to experiment with. From LED arrays similar to the newer MLD monitor to strange reflective transmission LED arrays. I eventually found a lens dissipated LED array. However the ones I had found still left a small hot spot on the final product. Then I contacted Harry at Figure 1 Harry Iverson of Pacific Illumination and his LED backlight retrofit for LCD monitors. Pacific Illumination, remembering him from a past TechFest I had attended. He had just got in some LED lens arrays that might do the trick. When I tested them they worked the treat. Now that I had my light source, it was Page 4 August 2016

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6 time to get to work. First of all, diving into an MLD is a bit daunting, but it only looks difficult. Just use care and take your time when working on them and things will go swimmingly. Start by removing the back cover (fig. 1). You will see a host of cables and confusion everywhere but fear not, it is laid out fairly well. The first thing is to carefully remove the LVDS lines going to the panels. Be sure to mark which is the front and rear panels, it will save you a headache later. Unscrew the two control panels from the plastic backer; you can leave them plugged in as you will remove the entire A/D board assembly as one unit. Unplug all the fans on the power distribution board as well as the large inverter power supply cable. Disconnect the touch controller from the touchscreen. Remove the four larger screws holding down the metal frame that houses the twin A/D boards. You should now be able to lift out the assembly and set it aside. Next, remove the three fans and their heat sinks from the plastic back panel. Now is a good time to note down if you need to replace any by spinning them up with a bench supply and see if any are screaming for attention or fail to spin. Once the heat sinks are removed, dislodge the wires going to the internal blowers from Page 6 Figure 2 Figure 3 Figure 4 the plastic housing. Disconnect the CCFL connectors from the inverter. Then remove the screws to pull out the inverter board. Place it in your spares as it will no longer be needed. Closeup of the concave lens and current-limiting resistor August 2016

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8 Once removed, take out the remaining screws holding the plastic back plate to the metal frame. You should now see the three blowers fans that are the prime culprit of the overheat failures of these monitors. You can now remove the fans and smash them with a hammer if you like or just save any that are still good in your spares. They will no longer be needed with the conversion. Now the fun part where you need to take a little extra caution, the removal of the LCD panels to get access to the light box and the CCFLs (figure 2). Remove the touchscreen frame. Unscrew the front LCD panel retaining frame. Unscrew the LCD driver board from the metal frame. Be careful not to put any undue stress on the flex connectors attached to the board or glass panel. Carefully remove the panel. It may be stuck down with age by the rubber gasket separating it from the frame. Using a plastic spudger, carefully pry it up from the frame. You should not need to use great force. Once the panel is free, carefully remove it and place it some place safe. Next remove the glass plate and frame separating the back panel from the front. Again, be very careful and place it in a safe place. Finally the back panel. Remove the shielding cover Page 8 Figure 5 Figure 6 Figure 7 August 2016

9 over the LCD control board, paying attention not to harm the flex connectors once again. Using your spudger, carefully unclip the tabs along the side of the mounting frame until the frame is free. Lift off the back panel and set it aside. You are almost there, just remove the diffusing sheets and panel and you should now see the CCFLs. From the back of the metal light box, remove the CCFLs from the frame. You can use your spudger to pop out the rubber boots holding them in place. Don t worry if the plastic clips holding the tubes in place break, they are often very brittle from age. You will not be needing them. All you will need is the stud going into the metal frame to hold on the white background reflector. After experimenting with different numbers of LED arrays, to achieve the same luminosity as the CCFLs and to provide an even back light, you will need to install four strip arrays (figures 3 & 4). Place them equidistant from each other, with the wire tails being fed through the former CCFL mounting holes. Use a good double sided tape like a 3M VHB. Use a thin tape, not the tape used to mount touchscreens. You will want the LED arrays to be as close as possible to the reflective white backer. Once adhered and your August 2016 wires run through the holes, it is time to reassemble the panels. Just use care and reverse the procedure you used to take it apart. A quick note, now is a great time to de-crud the LCD panels and the glass separator pane. Use some good cleaner and a soft cloth to take off years of gunk. You want your spiffy new LEDs to shine through. Figure 8 Once your panel sandwich is reassembled, it is time to wire the panels. To make it easier to route the wires, I drilled a few small holes in the plastic backer the inverter mounted to (figure 5). Secure the plastic backer panel to the metal light frame. Pairing the wires, two top strips and two bottom strips, tie in a connector with a little recycling by using the blower fan s power wires. Just snip and splice them to each paired LED module. A little heat shrink and presto! You are wired. Reinstall the three heat sinks and the three fans. These will provide plenty of airflow to keep internal temperatures of the monitor well within the safe zone. Replace the A/D board assembly, being mindful to connect the LVDS lines to the correct panels. Plug in your fans and your new LED array to the fan ports on the power distribution board (figure 6). Reconnect your touchscreen and attach your controls to the plastic backer. Before you power up the monitor, double check your connections, check for any potential shorts, frayed wires or other issues. Unlike many other repairs, you will have leftover parts. In this case it is OK. The parts leftover will be the screws that mounted the blowers, the blowers themselves, the inverter, and a pile of CCFLs (figure 7). Now fire it up (figures 8 & 9). Upon torture testing our prototype in our hot box test chamber (nothing more then an insulated box with Page 9

10 a Peltier cooler/heater that we can use to simulate various temperatures) we came up with the following data: Power consumption of the monitor went from 15 amp inrush, 8-10 amp run draw to only 4 amps (figure 10). In addition to the power saving, while running in an environment of approximately 24 degrees Celsius (74 F) the internal temperature of the monitor never climbed above 35 degrees Celsius (95 F) (figure 11). This test was conducted over a 25 day period, run for 24 hours a day. Overall picture quality over the test period was excellent. The part number of the LED module arrays is #6050 and is available through MCM, Pacific Illumination s distributor. The same process above can be used for any direct back light LCD. With many of those, you will only need to use three LED arrays. However, experiment and choose what is best for you. A little time and some effort will yield a great upgrade, extended life not only for the monitor but the power supply as well since it is not loaded down as much as it was. Good luck in your own conversion and happy tinkering! For question contact me via the Slot Tech Forum, handle: Spozgar or at greg@knmcasino.com. - Greg Agostini Figure 9 Figure 10 Figure 11 For access to schematic diagrams, service manuals, software and more, visit the Slot Technical Department at slot-tech.com Page 10 August 2016

11 Slot Tech 2 Tip-A USB Tester That Displays Voltage and Current It s pretty obvious what this is and what it does. Use a USB Tester to check your ports. They re only six or seven bucks each (I actually saw one priced at $2.50 from Bang Good- 2a8DeQj) so there s no reason not to buy a few dozen of them. Just do a Google search for USB Tester. I like the Keweisi unit because the display is big and bright, it displays both voltage and current without having to cycle through the displays (in two different colors) and it has two output ports just in case you need em. August 2016 Page 11

12 Quick Repair Slot Tech Sometimes, the simple repairs are the ones that impress me the most. I m not talking about a button replacement (although that may not always be so simple any more) but rather a quick, component-level repair that takes just a few minutes where I know that the same, simple repair might involve an entire monitor replacement for an operator who lacks this capability. Meet Shawn Ellis, one of the slot supervisors that covered the gaming floor while I had all of the slot techs in class at Pompano Park racino in Florida. During a break in class, I wandered out to the floor and saw Shawn working on a game with a bad LG monitor. The screen was blank. Shawn quickly determined that it was only the inverter that had failed. This skill allowed him to simply pull the inverter PCB rather then pull the entire monitor out as often happens. A quick electrolytic capacitor change (two of them, actually) and the original inverter was re-installed, all of this in about 15 minutes or so. That s what I m talkin about! - rf Two, obviously bad electrolytic capacitors killed the operation of this LG inverter. Page 12 August 2016

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14 Subscriptions & Back Issues Why back issues of are important to own... is strictly technical. As such, the magazine's contents are not time critical. The repair information and technical data contained in past issues is just as valid today as it was the day it was published. Additionally, current and future articles more-or-less assume that readers are already familiar with what has been covered in past issues. This editorial policy assures that Slot Tech Magazine's contributing writers are not limited to "writing down" to the level of a novice technician but are free to continue to produce the most comprehensive technical articles in the gaming industry. Randy Fromm's is published monthly by: 1944 Falmouth Dr. El Cajon, CA tel fax editor@slot-techs.com Subscription rates: Domestic (USA & Canada) 1 year - $ years - $ International 1 year - $ years - $ Back Issues Printed back issues are available for onlysix months from the date of publication. All single issues of Slot Tech Magazine are $10.00/ea. For further details on the contents of each issue, please refer to the website at slot-techs.com. To order, fax a PO or a note listing the issues you need. Complete archive (2001 to present) available online. Visit slot-techs.com for details. Invoice me! PO Number Company Name Contact Address Address City State/Prov. Country Zip/Postal Code Telephone Type of card: [ ] American Express [ ] Discover [ ] MasterCard [ ] 1 year subscription, domestic [ ] Visa [ ] 1 year subscription, international Account Number: [ ] 2 year subscription, domestic [ ] 2 year subscription, international Expiration Date:

15 I can help you bring down the cost of casino electronics repairs Randy Fromm OK. You asked and I listened. My new tech class eliminates obsolete CRT monitor repair and the associated monitor repair lab. In just four or five days, your slot techs can learn to repair Power Supplies, LCD Monitors, Ticket Printers, Bill Validators and more. It s easy and it s fun. - Randy Fromm tel fax

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