Repairing a 13” K7000 Arcade Monitor, building a Test Bench Power Supply, & Rejuvenating a CRT Tube
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- เผยแพร่เมื่อ 27 พ.ย. 2024
- Unfazed by the cascading issues popping up in last week's video, today Charlie is determined to get his 13" K7000 Wells-Gardner CRT test monitor back in tip-top shape! To accomplish this, he'll be assembling an isolation transformer test bench power supply, installing a cap kit, reflowing old solder joints, hooking the tube up to a rejuvenator, and dialing the colors back into adjustment. These practical skills are sure to come in handy as soon as factories start churning out new CRTs again...
Episode #43
Bob Roberts' Basic AC Wiring Map: www.therealbobr...
Bruce Christian's B&K Rejuvenators Facebook Group: / 503454524641474
Tubular - a searchable database of vintage displays and the CRTs that power them: tubular.atomiz...
Buffet's B&K 467 Rejuvenation Tutorial: • A Basic Rejuvenation w...
B&K 467 Rejuvenation Tutorial by DeLuSioNaL's Arcade: • How to Rejuvenate an a...
Wells-Gardner K7000 Monitor Service Manual: arcarc.xmissio...
Tools & parts used in this video (contains affiliate links):
SKIL Rechargeable USB Cordless Screwdriver amzn.to/3ROoqdF
Fluke 117 Digital Multimeter amzn.to/3CKpACT
Fluke AC175 Alligator Clips for Multimeter Test Leads amzn.to/3XcRhMi
Philmore TV Alignment Tool Set amzn.to/3ORdfRT
Kaisiking Large Silicone Soldering Mat amzn.to/3VfiXje
LUXOR LE27-B AV Utility Cart amzn.to/3HCFn94
Power Socket w/ EMI Filter amzn.to/3Nbb9vz
Red LED Rocker Switch amzn.to/3pdHCJy
AGC/MDL Fuse Holder amzn.to/3NzY3t9
120V Monitor Isolation Transformer www.arcadepart...
3A 250V Slow Blow 3AG Fuse www.arcadepart...
K7000 Series Cap Kit www.arcadepart...
3AG PCB Mount Fuse Clips www.arcadepart...
CraftyMech TPG Test Pattern Generator www.mikesarcad...
CraftyMech TPG Cables with Standard & Nintendo monitor adapters www.mikesarcad...
10 Pieces and 5 Colors Test Lead Set & Alligator Clips ebay.us/cKxhvW
B&K Model 467 CRT Restorer/Analyzer Rejuvenator ebay.us/r6sY23
Theme Music Credit: "Synthwave 80s" by AlexiAction (used with permission under the Pixabay License) pixabay.com/mu...
#crt #arcades #restoration #arcaderestoration #retrogaming #arcadegames #arcadecabinet #classicgaming
Hey brother! Thanks for the plug! Great video! Just wanted to throw out a quick note in reguards to using the clean and balance versus the rejuvenator. The clean and balance you can hold the button down till it reaches the .2 mark, and the rejuve process is stopped at the beginning of the red which is .4 I also like to wait about 10 ir 15 seconds between each color to let the caps fully charge back up. 👍👍👍
Great info - I’ll keep that in mind for the future! Thanks so much, Bruce!!
Great video, Charlie! I love how you explained the process step by step, from building the test bed isolation transformer to reflowing solder and doing the cap kit. It's so helpful for those of us who are into arcade monitor restoration. The before and after on the CRT monitor's display is quite impressive. Looking forward to more of your projects and restorations. Keep up the awesome work, and thanks for sharing your expertise!
Thanks, Shawn -- I'm glad you enjoyed it! I'll be recapping a 13" G07 pretty soon, too. And I think the voltage regulator on this 13" K7000 is still acting up...
Always like seeing the TPG in action :)
Thanks for making it, Aaron! The TPG is an absolutely essential tool for anyone who’s serious about this hobby!
Thankc Charle! That power socket with built in line filter is cool as hell! Thanks for linking it.
You know, I have to mute segments of your intro so I wont get spoiled with what's going to happen lol Thats a me thing though. Keep doing what you're doing!
Glad you’re enjoying my content! I can’t take credit for finding that socket/filter combo - @Lakeside-Arcade turned me onto it here: forums.arcade-museum.com/threads/electrical-gurus-test-bench-upgrade.523362/post-4683572
Also, you’d prefer more spoiler-free intros, or no intro at all?
@@overtimearcade Oh, intros are fine. I just dont care for the spoilers Weird i know.
Ok, I’ll try to keep them spoiler-free!
That k7000 is crisp!
Bright and tight!
Do you ever have trouble finding parts for repairing arcade equipment? I've heard people complaining on forums that repairing and finding Arcade CRTs is too difficult for them.
That the last CRT factory closed 15 years ago.
Great question! Generally speaking, I haven’t run into any major trouble with this sort of thing yet. Unless the glass of the tube has been cracked causing the CRT to lose its vacuum, virtually everything else on an arcade monitor can be repaired or replaced. Parts are available for most of the classic 80s monitors (G07, 4900, K7000, etc.) but some of the later monitors are far more complex, and a few don’t have good repro flybacks available, etc. So I guess it really depends on what you’re working on. And of course, although the factories have closed, there are tons of parts tubes & chassis out there to harvest from, if you know where to look!
31:50 Not sure if it's camera angle or this issue, but my monitor has a similar "twist" that I think is visible here (top left of image seems to reach the edge while top right is about a quarter-inch off). Is that about how the flyback is seated in the tube, or some other setting that can be adjusted with a pot switch?
Learning so much from your super informative videos. Thanks!
It’s a very common geometry issue. If you aren’t able to get rid of it with the typical adjustment pots on the monitor chassis (tip: try slightly adjusting the sync/hold pots to see if that helps), then you can look into adjusting the position of the yoke. That procedure is a huge pain in the butt to do though, so I typically just live with it unless it’s completely unplayable. I don’t believe there’s a flyback issue that could cause this sort of twist/curl.
Also, thanks for the kind words!
@@overtimearcade Thanks a mil! Yeah I can definitely live with it - very minor issue, plus I usually play in the dark and only really notice the "twist" when viewing the screen in the daylight. And then it's only really noticeable on test screens & games like Pac-Man where the playing field is a full-screen rectangle within the bent glass tube. I thought maybe there was a "skew" or "pincushion" setting/variance that might account for it. But no biggie. 👍
@@overtimearcade Thanks for all the clear information! You know, when I was a kid I dreamed of having my own arcade cabinet(s) as a grown-up, just to play on. Finally got my first one last year, and never knew how much I'd enjoy the rabbit holes of repair & maintenance & dialing in controls that come with the hobby. What a blessing for all us big kids that people like yourself make such a useful library of knowledge available and keep these neon dreams alive. Cheers!
I’m glad I can help support your dreams! 🤩
I've seen other videos with isolation transformers and they disconnect the earth line, stating that it's connected to neutral back at the main neighbourhood transformer, and so connecting the earth back to the chassis in this case, doesn't in fact do anything. Can you clarify which is correct, and why?
This was actually discussed on KLOV recently, and a member there who's smarter than me explained that the purpose of an isolation transformer is:
> to isolate the line and neutral from earth ground since the neutral and ground are tied together at the power entry point, typically the breaker panel. This "floats" the monitor from earth ground. For safety and to keep the chassis from building up a potential voltage due to capacitive coupling in the monitor you SHOULD tie the chassis (metal part of the monitor) to earth ground.
forums.arcade-museum.com/threads/electrical-gurus-test-bench-upgrade.523362/post-4685375
@@overtimearcade Interesting. So the chassis should be grounded to help dissipate capacitance buildup within the monitor chassis itself. This is good to know.
I'm going to have to run the oscilloscope of a separate isolation unit then, as it's meant to be grounded to the centre pin of the transformer. Grounding it to the mains ground can blow your oscilloscope if you end up dumping too much voltage through it, which can happen in a monitor.
Thanks you for that, and the link :)
No problem! As I understand it, the input voltage going into the monitor needs to be isolated from ground, but the monitor frame itself should still be grounded.
Thanks for the video's,,,,, Please help, ,,,The isolation transformer output has two wires, both with no reference to which is hot and neutral , which is okay! but then there's that green ground wire for safety? One side's output of the secondary's Iso's electrons are like BLIND MICE, they only want to go toward there easiest path home,, "the other side of there secondary". THATS IT. ..
So why add the safety ground, Or' is that just in case the iso fails to perform? also, Are both green ground clip and fluke's black lead USING THE SAME POINT OF REFERENCE for MEASURING B+? Thanks...ordering T shirts!
On the output side of an isolation transformer (i.e., secondary wiring), there's no difference between hot and neutral. There should not be a green ground wire coming out of the isolation transformer -- if yours has a green output wire, it could be an iso that provides multiple output voltages. However, many arcade manufacturers did connect the case/foot of the iso to ground inside the cabinet, similar to the diagram from Bob Roberts at the bottom of this page: www.therealbobroberts.net/acwiring.html
Also, for measuring the B+ voltage on a monitor, consult this page: www.arcadepartsandrepair.com/tech-help/monitor-b-settings/ Every monitor is different, but you should not be measuring B+ using the cabinet ground as a reference, but rather the monitor frame (typically).
What kind of solder and size solder do you generally use for these?
Hi Nicole, here’s the solder I use!
Kester 44 Rosin Core Leaded Solder amzn.to/3EvTY5i
@@overtimearcade oh dude you rock, ty!!
⭐️⭐️⭐️⭐️⭐️
🤩
I shocked myself with a CRT once lol not a good feeling
We’ve all been there. A few more times, and I’m hoping to develop superpowers. 🦸♂️
I believe you're not supposed to connect the earth to the monitor.
As discussed in the same KLOV thread linked in another comment, a monitor chassis should be connected to earth ground even on test bench setups for safety reasons:
> With the monitor running and "floating" there's parasitic capacitance between the frame and the AC voltages in the monitor. This can cause voltage to appear on the metal frame which can be a shock hazard. On my test setups I usually include a ground wire with a big alligator clip I can just clip onto the frame while it's on the bench. This is also important if something has failed in the monitor that may be shorting any higher voltages to the frame. You want to be sure you can touch the frame without getting shocked, this ground connection will ensure that.
forums.arcade-museum.com/threads/electrical-gurus-test-bench-upgrade.523362/post-4685461