Missile Command PCB fix

Board location E5 - 74160 dead output at pin 12 and other outputs suspect.

Confirmed as faulty in IC tester.

Fixed! :)

Arcade Garage 1.0

Well after close to four years, all the cabs I own are (touch wood!) working, Well I need a new starter for my Tempest Fluorescent light, but thought I best capture them while they all do work. My current line up consists of:

Fire Truck, Jet Fighter, Electrocoin Midi with a dual JAMMA adapter playing Pac-Land & Wonder Boy, Tempest Cabaret, Centipede Cabaret, Hang-On and Pole Position.

On the way to getting my current lineup I’ve also owned the following cabs: Lethal Enforcers, Cruis’n World, Missile Command Cabaret, Asteroids Cabaret, a Popeye Pachislo & 2 JAMMA cabs.

Photos below and a video, sorry for the lack of commentary but I’ve got a stinking cold at the mo and the vocals don’t sound too good.

ATARI Hot Wheels!

Tempest. Board repair.

This board failed on me back in March, and I briefly looked at it but didn't really have the enthusiasm to fix it at the time, fast forward six months and here we go again...

So upon re-testing the boards, the X axis output had stopped working, this was caused by a failed TL082 at location D/E12 on the main AVG board, pin 7 wasn't outputting anything, I fitted a new socket and replacement IC and had a stable output again, back to where I was six months ago.

Last week I got stuck into this fault again, (Crazy vectors and Showing Mathbox error in test mode) I have spent a good few hours probing with a scope and logic probe to try and track down where the issue was, I got the schematics printed onto A1 paper at work, I even de-soldered all the proms from another Tempest AUX board to double check my proms had verified correctly, which they had.

Now, convinced that it wasn't a Prom/Bitslice/Socket or Interlink cable, I honed in on the remaining IC's in the Mathbox area. E4 a 7408 (quad 2-Input AND gate) got my attention, now I'm not really proficient enough in fixing boards to understand what was wrong but pin 6 which drives the clock input of B1 (374) didn't look pulse correctly on my logic probe, the frequency of the pulsing was all over the place and the HI/LOW LED's were going 'mental' in an odd way. I tried piggybacking a known good chip onto the 7408 to no avail, not deterred I de-soldered it and put a socket on the board. I then tested the IC in my Programmer which also tests 74 series logic, and sure enough one of the gates reported faulty. I put a new 7408 in and BOOM! The game is working again!

I have ordered new TL082's, MC1495's, trim pots for X/Y size/position adjustments and will fit these when the arrive to hopefully improve the reliability of this board, but for now I think I'm due a few credits. :)

New kids in the arcades....Animal Kaiser

So I just got back from a family in North Wales, I visited a few arcades and found them full of redemption machines, pushers and it has to be said a good stash of new sit down drivers and an Afterburner Climax cab. 

I never spotted a 'classic' machine on my travels, but I did stumble on a machine that was new to me; Animal Kaiser. At first from a distance I thought it was a new Sega Dino/Mushi king type cab upon close inspection it is a Bandai Namco cab. The game in a basic form is player one vs computer or player one vs. player two. You are an animal and you battle against your opponent. You only have two buttons, one chooses your attack and the other chooses the attack strength. Simple enough but, there is added excitement that after each game you get a game card which can be used in you next game. There are three types of card: 1) A red 'Animal' card, If you have one of these you can play with that animal in your next game. 2) a Green 'Strong' card that increases the power of you attacks and finally, 3) a Blue 'Miracle' card which acts as you special move.

When you start a game, you scan one of each card if you have them and that combines your strength and health and special attack. The games consists of three rounds (If you last that long) fighting a different animal each time with the big boss in round three. The game is like a skill stop selection, your first button press chooses your attack type which is dependent on your cards, and next button is the power of the attack, the game then takes over and shows you being attacked or you attacking the other player depending on who had the best attack. The idea is to knock their health down and wipe them out. Whether you win or loose, you get a new game card at the end of the game. As the name goes all the cards are based on different animals and in true collecting style some seem to be plentiful and others can be Gold/Silver & Bronze 'Rare' cards and one card is labelled as 'Ultra Rare' which is the character with the most strength.

I was amazed in the evening that these machines were packed with kids wanting to play all night long, at one pound per play these machines would have been making the operators a very good return. Not just that but there was a real buzz around the game and who had which card, a classic moment for me was when a small girl came up with her dad, he got some game cards out of his wallet and as she scanned them there were real gasps and cheers from everyone as she scanned the Ultra Rare 'Seigfried' card, this will be an awesome moment in my arcade memories as it was great to have my kids really getting a buzzing arcade experience. Lots of very jealous kids standing by in anticipation watching her game! We all had smiles watching, but she didn't make it though all three rounds even with one of the best card.

Between myself and my two kids we spent about £50 on the game over seven night, we got a few of the rare cards and the kids now want me to get a certain machine for the home arcade. lol. 

From researching since I've been back these machines have been around a fair while with these cabs having 2007/8 copyrights over them. This game was labelled revision four which is new in the UK, but there seem to be at least another four versions that have been released worldwide to date. See below for a few photos and a video of Son number one playing. Each game lasts around five minutes which in today's arcade, combined with the fact you get a card is pretty good value entertainment in my opinion.

After watching the games being played for a few days one finally ran out of game cards which needed an Op to open the cab up and put in some new cards, I took a few blurry photos as you can see below. There were 600 cards in the box and they were labelled as A,B,C & D. I couldn't tell if they went into different compartments and wonder if certain packs contained the Animal/Strong/Miracle cards etc.

Game cards in the box above, and the (blurry) service menu in the photo below.

Our card collection, including a Gold Rare and some Bronze Rare's.

If you want to find out where you can have you wallet emptied there is a map on the Facebook page that shows current game locations in the UK.

Animal Kaiser UK website

Animal KAiser UK Facebook Page

Thanks for reading, Mart.

Pole Position. Post race analysis

So the cab is now as complete as I'm going to make it. If I had more space I would do some cab woodworking to fix the broken corner then finish off with new T-moulding, but for now this is it.

A can of black satin spray was used to cover the new section of MDF at the bottom of the cab along with the recently made back door, the finished result can be seen below.

Another item on my list of thing to do was to make a cardboard monitor surround which site in between the front glass and monitor, I had no original surround for this so I made so I slowly measured and cut the card, the final result came out OK, not perfect but better than without one.

I finally got round to spraying the coin doors and fitting some new reject labels. I took three attempts at spraying the doors, mainly due to the fact I didn't sand and clean them well enough to begin with!

To finish thing off on the cab I finally applied the steering wheel sticker I bought a while back from arcadefixit.com

In true Pole Position style the game board has gone belly up just as I finally get things finished! After having a few games recently the cab decided that it wouldn't coin-up or go into test mode even though attract mode was still happily playing. Upon re-powering the cab I am now greeted with a blue screen full of zero's :(

*Update1* Mark at Retroclinic fixed the board set for me, I lasted a few weeks before failing again.

*Update2* I am now going to wait for Adam Courchesne to finish his Pole Position clone board before dropping any more money into this cab/

Atari Jet Fighter. PCB Repair Part 2...

Well after have a fair amount of play recently and being switched on for 10+ hours, Jet Fighter developed a fault when switched on a few days ago...

In attract mode the Black Jet was erratically flying backwards, not something I'd seen before with this board. When you started a game the Black Jet carried on flying backwards and the left/right rotate controls we not working for either Jet.

I started probing around the vertical and horizontal motion counters to see if I could track down the issue, there are four signal J1C0-J1C3 which are derived from a 64-bit RAM IC, probing these for the Black Jet circuit I found that they were all stick high and not pulsing as I would have expected.

This board is quite nice as the Black & White Jets have pretty much identical circuitry so it was easy to compare one with the other.

Checking out the other pins on the RAM, I found that the W/E pin was being held high, I traced this back to an LS7432 (2-Input OR gate) and confirmed that the output was stuck high (confirmed against the White Jet circuitry). I cut the output pin on the 7432 and was still stuck high and not pulsing away. Once swapped out with a replacement, The game is fully working again.

Schematics showing the area of the fault this time.

Atari Jet Fighter. PCB Repair.

Back in March I fired up my new cab and was pretty happy with the results, The game powered up and seemed to work, with exception of what I took as a graphic fault seen below where the Jets were displayed multiple times vertically down the screen. 

Original testing in March. 

I decided I was going to spend some time to look at this board this week just gone. My initial diagnosis above was not quite correct... Looking closer at what was on the screen the 'Jet' graphic was not complete and had bits missing especially noticeable in the white Jet. Also it was not possible to score points, I thought it may be due to the fact so many Jets were on screen at the same time. So I was looking at multiple faults already, and as (bad) luck would have it, after having the board on soak for a few hours I looked at the screen to check the game was still running and all I could see was a black screen! A few expletive's came out of my mouth and then I re-powered the cab, the image below is what I now had to work with...

The black 'Jet' and 'Score' were missing and instead of having a solid light background colour there we now horizontal bands in alternating colour going down the screen. (difficult to see in the photo below, but move visible in the photos further down.)

The fault log begins with this screen.

I have a copy of the Operation & Maintenance manual and it has some great description of what signals control certain aspects of the game, this certainly aided my fault finding, I also printed some A3 schematics that I could mark up in pencil and highlighter pens.

Initially I did go round the houses trying to work out where in the circuit the faults were, but after reading the manual a few times and following the signals in the schematics I got hot on the trail of issues, cutting to the chase, the faults were as follows.

IC location F3 a 74LS10 (3 input NAND gate) now had no output from pin 12. This provided the Jet/Score and Shell for black Jet.

Black Jet & Score back, but Jet video is inverted.

So with video back, I played a few games and noted that the score wouldn't increase when the Jets were hit with shells and the fact that no explosion registered to say the Jet had been hit. As it turns out another 74LS10 this time at location E1 had no Output on pins 6 & 8, these are the two trigger signals for Jet 1 & 2 respectively that further down the circuit chain pulse a 'BLO UP 1/2' signal which is used for detection of a hit. With this IC changed the score now worked and Jet explosions happened when hit by a shell.

Scores now working

The White Jet graphic was slightly corrupt not correctly displaying properly, The data for plane comes from ROMS at J5 & K6 (2K each). This data is shared between the two planes, so as the black Jet looked fine (although inverted) I was pretty sure the ROMs were OK. The ROM data is fed into a pair of Parallel to serial converters. For the white Jet they are at locations J4 & K4. Pin 7 of K4 provides the serial data through a few more IC's before becoming the Jet 2 video signal. The IC clearly was outputting something as you could see the image on screen, but my Logic probe was saying that pin 7 had no signal (High/Low or pulsing) Pin 9 is the inverted state id pin 7 and although not used in the circuit appeared dead too. I compared this to the Logic to the Black Jet and those same pins were pulsing along nicely. Time to swap K4, once replaced the Jet graphic was spot on and working.

I needed to get to the bottom of the 'multiple Jets on screen' fault that this board has had since I first turned it on. I'll put finding this fault down to mild guess work and lots of general probing around. I had the opinion that the issue was in the Vertical motion counter section of the circuit. Seeing as the fault was on both Jets and that each Jet had its own counter I had a hunch that these weren't directly the fault. The output from the counter for both Jets was fed into a 74LS74 flip flop IC. Pins 5 & 9 are the output pins which are mixed with the Horizontal blanking and Horizontal Jet position. They were stuck low. I cut one of the pins in circuit to confirm nothing else was pulling the pin low and it stayed low. Time to replace it...
Wohoo! Fixed as shown below, just the inverted black 'Jet' video and the background bars remaining.

Only one black Jet (Video inverted) and one white Jet.

More general probing around the final stages of video signals before they are joined in a resistor network found me this fault, IC at E4 an 74LS08 pin 6 provides the final video data for the White Jet. (Jet video and H/V blank info) As with the earlier fault the output was working but using a logic probe gave odd results, I did 'piggyback' an IC on top of the one in circuit and the background issue was gone, so I replaced the IC and that left the inverted video fault...

I remembered reading in the manual that when a Jet was hit by a shell the Jet's video was briefly inverted, to me it seemed this was happening constantly. The 'BLO UP' signal comes out or a 2 input gate at position K8, the logic probe was telling me this signal was constantly low, I monitored this in a game and made a white shell hit the black Jet, the output on the gate stayed low. Next up I cut this pin and re-powered the game. The Black Jets video image was now the correct was round, using the White Jet I fired a shell at the Black Jet, the game functioned as expected but without the brief inversion of video (that pin now wasn't connected!) So I replaced the IC and for now the game is fixed and fully working.

I've really enjoyed getting these faults fixed and think I've learnt a fair bit these last few evenings. Now its time to sort the cabinet out.

Cheers, Mart.

Background banding issue fixed, inverted Black Jet video fixed. Game...Fixed!