Due to a large amount of spamers, accounts will now have to be approved by the Admins so please be patient.
×
-
Recent Activity
-
15
Is It Possible To Make A Homebrew Pinball for under $5000 ? PLAYFIELD AND PLAYFIELD PARTS
Interesting theory, But unfortunately that would make it generic in nature… Close your eyes and see it, Know what you are going to build, because those characteristics can change the entire structure and strategy of “How it was build” all the way down to its very core… And while we are one the subject of development CNC, 3d printing, and CAD all have a level of accuracy that can actually change that design and deter quality… I notice there has been no mention of templates yet and fitment… Not trying to tell you what or how, but these things are very linear in nature. -
15
Is It Possible To Make A Homebrew Pinball for under $5000 ? PLAYFIELD AND PLAYFIELD PARTS
The light is used if you need a light, nothing more. As for it matching a theme or a name, I think to many people get hung up building to either because if you think about it it is usually just the toys, the sound, the art and video that sets the theme and name. To start on these 4 steps first would be building in reverse. Priority should be the layout and the entertainment value it offers first and foremost and then the other 4 can be made to suit what name and theme you choose. Most production machines had there whiteboards tested "unnamed" way before any name or theme is allocated and often had last minute title changes so no, I put very little to no priority to building the other way around......Too many restraints. You can paint, sound and toy any whiteboard to a theme but if the layout is crap, it's a dude. -
2
WTB: Bally Xenon
I think Oscar @Pinmem just listed one recently too maybe? -
14
C.R.O. Crash Course - analog test gear in a digital world
OK, we've done some basic setup and triggering excercises with our CROs and it's time to try a few measurements on our actual game PCBs, hopefully identify a fault condition and possibly trace it to its source. This is the point, @yngbld where it will help if you still have a video PCB with graphics issues which we can compare with my working PCB. Anyway, I'll take a few measurements which you may be able to duplicate and see if we can spot any issues... We've looked briefly at the final analog video output from the CPU PCB, this is built up from multiple layers of graphic components, scrolling backgrounds, text and large sprites. The sprites include the cars, some scenery such as trees and tunnels as well as animated title graphics and originate from the video PCB. At that stage the graphics are in digital form so instead of comprising three analog signals representing R,G and B components there are 13 bits of data, I'm assuming 4 bits per colour and 1 bit which may be a key signal, to determine the outline of the sprite which will be superimposed over the background layers. We can begin at the point where the sprite graphics leave the video PCB and are sent to the CPU PCB over the 'F' interconnecting cable, working back from that point. The final stage is a bank of 13, 74LS166 8 into 1 bit shift registers . Each takes a byte of data at a time, shifting that out bit by bit. Each group of 13 bits at the output of these shift registers would represent one pixel of a sprite graphic. The outputs are only active when there are sprites to appear on screen. Referring to the Chase HQ Schematic (Taito) page 21 of the Video PCB circuit (page 45 of the 47 page .pdf document) the bank of 13 x 74LS166 shift registers are shown. Each takes a byte of data at a time from the FRD bus (I assume that refers to frame data) and outputs bit by bit to the OBB bus ( objects?) which goes to the CPU PCB via the 'F' ribbon cable (FCN). A small excerpt of the diagram shows the ins and outs... And we can see the 13 ICs in question on the video PCB here: The main difference between using a logic probe to test signals on a circuit and an oscilloscope is the logic probe can only tell us if signals are present and active but not whether they are complete or relevant to the intended function. To give the signals we are viewing some meaning we need to set up our oscilloscope to trigger and view the signal in context to the overall process. So as trivial as it may seem, the most important stage is to set up the trigger. With experience we can just look at a signal then set up a trigger to get a clear picture but to demonstrate more clearly we'll do the trigger first using a setup we've already practiced, looking at video lines. We'll use our composite sync as our trigger source and we'll keep it visible on our display to use as a reference so select dual channel mode. I usually put channel 1 in the top half of display and channel 2 in the bottom half. At 10 microseconds per division with channel 1 as our trigger source and using TV trigger (or DC trigger if there is no TV setting) negative slope and adjusting our trigger level so the horizontal syncs are steady and not jumping around. We can use the horizontal position control to see the initial trigger point and one complete line period to the next horizontal sync. If we've set it up correctly the second sync should appear just over 6 divisions after the first (64 microseconds or 6.4 divisions at 10 usec / div.) Once that is set up and stable we can look at the data at the output of each shift register, pin 13 using our second channel. The data is TTL level so we can set our Ch. 2 gain to 5V per division (or 0.5V per division using a 10x probe) We'll just leave the attract mode running on our game, as below. As the scene changes sprites appear and move around. At some points there are no sprites on screen for example the game instructions which tell us to 'bumb' into the 'climinals' are on a scrolling background layer so we just wait until there are sprites on screen to check each shift register output. As long as we keep our trigger signal on Ch.1 steady the output of the shift registers should be active, depending on the sprite activity, during the active video line period. The intensity will seem to vary as the lower order bits may toggle very often and high order bits may seem more solid on the display but all 13 should have activity at various times. The images here are all from a working PCB. In the image below the chase car sprite is on screen towards the left. As the attract mode continues other sprites also appear and move around. The main problems we are looking for are dropouts where some positions across the line are always missing, or incorrect data levels. Another image below where the sprites are mainly situated towards the left of screen. The blip towards the right of the active line, just before the next horizontal sync is the blue 'progress bar' which can be seen on the monitor image above showing the distance from the chase car to the target. So all of the images above are OK but if a video board has an issue where sections of a sprite are missing or lines which look like 'jail bars' appear at regular intervals on the sprites these may be visible on one (or more) of the shift register outputs. and can be traced further back. I don't have an example of a faulty board to show at the moment but can show one I prepared earlier. In the image below a dropout can be seen which occurred in certain positions, only on particular lines in this case but the type of issue we are looking for may have a similar appearance to the bottom trace below. Anyway I hope that helps to illustrate one potential method for locating a graphics fault, starting at the irregular output and working back from there. As always when fault tracing, take your time and take care not to short adjacent pins when probing IC legs etc. Regards, John. -
7
Steelers EM meet late 2024
Don't pick the 3rd Weekend in September - Pinfest is on in Newcastle.- 1
-
3
Sammy Atomiswave SD Clean Up
There's probably a little tiny bit of sweat juice stain under the joystick edge.. outside of that, this cab is pretty immaculate. Yes, it's dirty and has a couple of rough stains, but nothing that some elbow grease won't remove. I honestly can't complain. The "collection" of the Monitor was one day, but that was more hanging out and stripping bit and bobs to make one really nice ID3. The tube swap took me roughly 1.5hrs by myself - that's start to finish. It wasn't much work. I mean, this whole cab isn't much work to begin with. If novus 1,2,3 doesn't work on the bezel, that will probably take the longest sanding it down and then repainting- 1
-
1,545
-
7
Steelers EM meet late 2024
have just bought this grail pin and about to import. will be here ready to go most beautiful backglass ever?- 2
- illawarra_steelers replied to illawarra_steelers's topic in Competitions, Tournaments and General Meets -
915
LAST FLIGHT OF RED BARON
I have decided that being banned from build sites is not in my best interest, So Jenni has taken the liberty to “Un-ban” Herself across multiple sites…Be suspicious of Noobies asking questions, You lurkers have been warned. -
1
WTB: Bally Fireball 2 pinball
Hey buddy, I recently got some items from Jeffery and he is willing to sell a Bally Fireball 2 also. You can email at jefferygalonsky@gmail.com if he still has it.
-
Forums
-
Site Information and General Chat
-
- 6.3k
- posts
-
- 62.1k
- posts
-
- 2.4k
- posts
- TAZPIN 2024
- By Cruiser,
-
- 226k
- posts
-
- 9.9k
- posts
-
Community Maps (3,665 visits to this link)
-
- 1.7k
- posts
-
-
Pinball
-
- 217.3k
- posts
-
- 4k
- posts
-
- 42.1k
- posts
-
- 48.8k
- posts
-
- 8.6k
- posts
-
-
Arcade
-
- 75.3k
- posts
-
- 68.9k
- posts
-
- 43.6k
- posts
-
- 27.7k
- posts
-
- 53.5k
- posts
-
-
Aussie Arcade Sponsor's
-
- 3k
- posts
-
- 2k
- posts
-
- 6.3k
- posts
-
-
Aussie Arcade Market Place
-
Consoles, Computers and Jukeboxes
-
- 43.8k
- posts
-
- 20.7k
- posts
-
- 1.4k
- posts
-
- 7.6k
- posts
- Rock Ola 452
- By wirraway,
-
- 8.8k
- posts
-
-
Who's Online 20 Members, 0 Anonymous, 275 Guests (See full list)
-
Member Statistics