[Restoration] The Joust Begins ...

[level42]

It depends on how the component is used in the circuit. If there are things in parallel across a resistor f.i., you will measure a lower value than the actual value of that resistor itself. To verify that 100% you would need to unsolder one leg and then measure over the compontent.


If the legs of the diodes are not making good contact, measure them from the solder side. This is where the component makes contact with the rest of the circuits so there is must be good.

You say you don't have a continuity test, but it looks like you do have a diode test, that's almost always the same.....
Even if there is no continuity test, you can always select the ohms setting. A wire, or PCB track should give a reading of about 0 Ohms.

I too am very careful with water but when coming to having to remove base material that has leaked out of the batteries you HAVE to rinse (I'd translate it a bit with spulen Ully) it with an acid (white vinegar, we call it cleaning or household vinegar). However, vinegar is an acid so you have to make sure it is GONE from the rest of the PCB surface and components and water is a good way to do it. Just make 100% you dry everything right away (hair dryer) after using the water and make sure EVERY corner and component is water free. It tends to "stick" in small holes etc.

However Ully, I think you're on the wrong track to repair this board. The components where you see the blue stuff is the diode that protects the battery from being put in in reverser order (if someone reverses the batteries it could blow up parts further up the circuit, that's why they put in that diode to prevent that. The worst thing there could be is that the battery voltage is not reaching the memory. THe only result of that would be that it won't save it's data, nothing else.

Also, you can probably get rid of the blueish stuff using some Q-tips with vinegar, it looks to be very small and it's not in direct contact with tracks or parts.

[level42]

alcohol is "fat", leaves residue (soldering tips from school and other tips form firends that repairs tv's and other electinics things).

Nonsense, not the 99% stuff you get from a chemists. It evaporates almost instantly.

Read this (under "Use"): http://en.wikipedia.org/wiki/Isopropyl_alcohol

[Superully]

could you check what that guy on klov wrote, please - to me that's technobabble (like the stuff that geordi said on the enterprise )

http://forums.arcade-museum.com/showthread.php?p=1291383#post1291383

[flip971]

could you check what that guy on klov wrote, please - to me that's technobabble (like the stuff that geordi said on the enterprise )

http://forums.arcade-museum.com/showthread.php?p=1291383#post1291383

From KLOV: "Andykmv: Diode D1 is probably a semtech corp IN5617 diode, which in the specs is listed as a fast recovery 400v 2a diode.
Diode D2 next to it should be a garden variety IN4001 rectifier diode.
not too sure on why you are getting a -ve 500 reading in the diode. the value is the forward voltage. probably stuffed so i would replace it.
Basically the two diodes form a simple switch arrangement so that during normal powered operation, power to the cmos ram circuit is provided by the 5v rail through D1, but when power is shut off, as the power supply circuit drops voltage, it reaches a level at which the battery backup for the CMOS ram takes over powering the cmos ram via D2 (around 4.7 volts iirc), and the cmos ram is write inhibited to prevent writing spurios data to cmos during shutdown..

R28 supplies power to the circuit that controls whether or not info is stored in the cmos ram, so if it is NOT getting power to that circuit, the game may want to come up in bookkeeping mode.

measure the voltage of at pin 11 IC51 (should be a 7425 or 74ls25 IC) - it should be roughly 4.75 to 5v with the game ON. you may also need to check the transistors

i would also check the operation of ZR1 (far left, 6.8v zener diode) and replace if the voltage is incorrect,

also the resistor, capacitor, transistor compoonents around that area are part of the RESET circuit which you really want operating properly. as yellowdog said, i would desolder any corroded components and replace with new components and fresh solder. inclding R28 & D1 (if you dont have an IN5617 avail, try an IN4001 temporarily) "

Andykmv is just sayng what tipe of diode are D1&D2 and which type You can choose to sobstitute.
R28 power the circuit of the ram, if it didn't work the game start in "bookkeeping mode".
Try to check on the IC51, the pin 11 for the voltage (between 4.75v and 5v game powered); also check the transistor aroun the IC.
For the ZR1 (is the diode zenere near the place of the batteries), check if put out 6.8V, otherway, replace.
In particular, chech the Reset circuit zone all the resistor, capacitor and transistor.
Yellowdos suggest to replace directly (whitout testing) all desoldered and corroded components included the R28, R26, D1 & D2.

Level42: alcohol isopropilic and "normal" alcohol are different.

[baritonomarchetto]

Sorry for pushing this up Ully, but did you had some progress on this awesome cabinet?

[Superully]

don't worry, push-ups are nice

update on this: got the roms back from sascha, one had a bent / broken leg (but i guess this happened during removal), sascha has burned a new one for me. some guy on klov suggested to try something else, but i'll have to install the roms for that test first. however, i'm working hard on the jungle king atm in the room where the joust 2 is stored. working hard means filling, sanding, filling, sanding, filling, sanding, ... - which produces a lot of dust. because of that, the joust 2 is wrapped up entirely to keep it clean. i'll be done with the cabinet repair part on jungle king probably tomorrow, so i'll have time to do some test on j2 at the weekend!

thx for asking

[baritonomarchetto]

Remember to give a crimp to the connector from the CPU board to the ROM board before testing  (on KLOV someone reported that the connector sometimes is faulty).

[Superully]

made some progress on my joust 2 - remember: it didn't start the rom test!

a friendly guy from KLOV (thx andy ) recently picked up a joust 2 himself, got it up and running and kindly offered to help me solve my joust 2 problem by comparing values of his machine with measures taken on mine - therefore slowly but surely isolating and eliminating the problem. before we could get going, i had to buy some testing equipment (mostly cables) and print-out the mystic marathon schematics which are extremely close to the joust 2 ones (which for some obscure reason don't seem to exist - or at least are not around). when i had done my homework, we wanted to start with some simple tests to ensure i'm able to read schematics and understand what he's telling me to do. so far, so good ...

one of the first tasks i got was to measure the voltages on a certain capacitor. that capacitor however was soldered very closely to the board, which meant i had to take the measures from the back of the pcb. however, the board was still fixed to the metal plate inside the cabinet, so in order to get to the back of the board i had to remove some screws and pull the board out a little bit. turned off the game, removed the screws, pulled out the board, attached the lead hooks from the multimeter, turned the game back on for the electricity to flow through the board and guess what ... i hear a sound from the front which i hadn't heard before.

i anxiously walk around the cabinet to have a look at the monitor and here's what i see



the test sequence has gone through the rom test, all the roms have turned green - yeah baby

what follows is what i will call the "baritonomarchetto effect" from now on, because the same thing which went down on his joust is happening on my joust 2!

after the successful rom test, the following screen appears



another good sign! up next: this



the hi-score battery is installed on my pcb (thx again, andré ), so i should be able to leave the bookkeeping settings by pressing the advance button (one of three three buttons behind the coin door) - at least that's what i thought!



however, pressing either of these buttons doesn't change a thing, the screen remains stuck in the bookkeeping screen. i've read somewhere that this could be caused by a closed coin door (which holds the interlock switch in position) and since i'm working from behind the cab, i'm opening the coin door to release the interlock switch, but nothing changes at all. i push and pull the interlock switch manually, but with no effect: still got the bookkeeping screen on the monitor!

it looks as if the three buttons and the interlock switch are not getting any power and are therefore not responding, making it impossible to leave the bookkeeping screen and to start a game. and before you ask: YES, the wires are connected! i have no idea what to measure where and andy from KLOV isn't around this week, so perhaps someone else has an idea on what to do ...

don't get me wrong, i'm totally happy with where i am now compared to weeks ago and i have the feeling i'm extremely close to finally being able to play my first round of joust 2 on this cabinet - it only needs that final touch!

anyone know how to solve the baritonomarchetto effect?

[baritonomarchetto]

I dont remember what happens when the advance button is pressed after bookkeeping are cleared, but for sure the next time you switch off and then on your machine the game should start. Looks like your machine doesn't sense that the switches are closed.

Try to see if the two switches (the one that sense the back door and the one sensing the front door) are correctly working. I made the test using my multimeter: when you "close" the switch you should have continuity between the two pins (essentially the interlock is grounded).

If this doesn't give you results, try grounding directly the interlock pin (not sure where's on the Joust 2 PCB, but on joust it's on the CPU board).

If the 2 interlock switches are working, you have a problem on the interlock sensing circuit and you will need a logic probe to check this.

Anyhow, the "baritonomarchetto effect"   is actually more related to CMOS RAM problems (i cannot get rid of ATM    )

[Superully]

I dont remember what happens when the advance button is pressed after bookkeeping are cleared, but for sure the next time you switch off and then on your machine the game should start. Looks like your machine doesn't sense that the switches are closed.

agreed, but as i've said: the advance button is not working. turning the game off and then on again doesn't change a thing, game comes up in bookkeeping!

Try to see if the two switches (the one that sense the back door and the one sensing the front door) are correctly working. I made the test using my multimeter: when you "close" the switch you should have continuity between the two pins (essentially the interlock is grounded).

the switch on the backdoor is working perfectly, i can pull it out with the backdoor open and the game starts. no reaction at all on the coin door interlock switch, nothing happens, no matter whether i pull or push it. did i understand you correctly: for a test of the coin door interlock switch, i "close" it by pushing it in (as if the coin door were closed) and then - with a multimeter - i check for continuity between the two pins to which the interlock switch is soldered? is that correct?

If this doesn't give you results, try grounding directly the interlock pin (not sure where's on the Joust 2 PCB, but on joust it's on the CPU board).

how do i do that? and what about the other three buttons? are they supposed to be working once the interlock switch is "closed" / grounded?

[baritonomarchetto]

agreed, but as i've said: the advance button is not working. turning the game off and then on again doesn't change a thing, game comes up in bookkeeping!

The same result happens if one of the switches are bad, so my suggestion was to check if the switches are ok first. To check the advance button, check the button itself for continuity when depressed : it's a NO (normally open) switch so when up is open, when depressed down is closed. The inverse is true for the autoup/manual down switch which is NC (normally closed). Then check if its connected to the board and if you have contiuity between the two pins (advance and ground) when depressed.

the switch on the backdoor is working perfectly, i can pull it out with the backdoor open and the game starts. no reaction at all on the coin door interlock switch, nothing happens, no matter whether i pull or push it. did i understand you correctly: for a test of the coin door interlock switch, i "close" it by pushing it in (as if the coin door were closed) and then - with a multimeter - i check for continuity between the two pins to which the interlock switch is soldered? is that correct?

With the backdoor OR the front door open the game should go to the test, and the game (meaning the playable game) should not start. The white switches (and i refer to the white objects themself, nothing to do with the game board) have couples of pins (2 or 3 couples, dont remember) that are connected when the button is pressed, not connected when it is released (like a microswitch). Check if they are ok or not. The check of all this buttons/switches can be done with the game shut down, it's only an hardware check.

how do i do that? and what about the other three buttons? are they supposed to be working once the interlock switch is "closed" / grounded?

Only for testing pourpouses, grounding the interlock pin (connect it directly to the ground) will help you figuring out if the problem is in the white switches themself or on the board. If the bookkepping screen is shown, there's a problem on the interlock circuit. If the game starts one or both your white switches are bad.

[Superully]

ok, had some time in between hours to do some testing. here are my results so far:

- both interlock switches are physically fine
- both interlock switches react to the continuity test once they are pressed
- the advance and the highscore reset button react to the continuity test only when they are being pressed
- the autoup / manual button reacts to the continuity test only when it is NOT pressed
- i have followed the autoup / manual button wires to the board and checked for continuity there - beeeeeep!
- haven't been able to check the wires of the other two buttons though because i was running out of time

summary: so far all the tests have provided the results one could expect from a working set of buttons / switches, guess there must be a problem on the interlock circuit then, right? but: can the interlock switch on the backdoor work and the one on the coin door does not? aren't they both using the same circuit?

input please

[baritonomarchetto]

Your inputs dude 

summary: so far all the tests have provided the results one could expect from a working set of buttons / switches, guess there must be a problem on the interlock circuit then, right?

It's a possibility but we have a couple of other check before stating this

but: can the interlock switch on the backdoor work and the one on the coin door does not? aren't they both using the same circuit?

They use the same circuit (they are connected to the same cable, at least on joust), so if at least one phisical switch is bad, the result is negative.

Now, you have a couple of things to check in my opinion before going to deal with the circuit

- check the battery. I know that Andrè made the work, but it's possible that moving (shipping?) the board the connection to the board has gone bad (it happend to me with the final version of my battery hack... nothing to do with the hack i uploaded some time ago  ). To do this, check the voltage between ground and something (for example a diode leg... it is probably the first thing you will encounter following the track) connected to the track connected to the other battery end (the positive one). This will help you check for real juicing between the battery holder and the PCB.

- enter test mode by depressing the "advance" button, switching off then on the machine and by keeping pressed the "manual down" button: what happens? You should be able to perform a one-by-one test instead of the "all-in-one" test. If not, there's ALSO something on the wiring of the 3 switch.

[Superully]

- check the battery. I know that Andrè made the work, but it's possible that moving (shipping?) the board the connection to the board has gone bad (it happend to me with the final version of my battery hack... nothing to do with the hack i uploaded some time ago  ). To do this, check the voltage between ground and something (for example a diode leg... it is probably the first thing you will encounter following the track) connected to the track connected to the other battery end (the positive one). This will help you check for real juicing between the battery holder and the PCB.

i don't quite understand where to put which lead from the multimeter, is it possible to mark two spots on either of andre's pictures?

- enter test mode by depressing the "advance" button, switching off then on the machine and by keeping pressed the "manual down" button: what happens? You should be able to perform a one-by-one test instead of the "all-in-one" test. If not, there's ALSO something on the wiring of the 3 switch.

just to clarify: i turn on the machine with the advance buttons pressed (and auto-up?), this brings me to the bookkeepings (what's the use of depressing the advance button, the machine comes up in bookkeepings anyways?!?). from the bookkeepings screen, o turn off the machine, press down the middle button to manual-down (do i have to keep it pressed or is it ok if it "locks" in?) and turn the machine on again? i'm a little bit puzzled as you can see

would be great if you could clarify this a little bit further, i can't do the tests today because i'd have to go to my mother's place, but i'd like to make it noob-proof before going over tomorrow ...

by the way, what's up with arcade guys storing stuff at their mother's place? greetings to bruno and etienne from ully

[baritonomarchetto]

If i see well, with the voltmeter check between the hole (it must be grounded so you can measure from it) and the diode leg



You should measure 3V (maybe something less). If there's no voltage you have a bad connection from the battery holder. If there's less than 2V it is possible that one of the 2 diodes (the one arrowed and the one close to it) is bad (one of those should essentially stop the board being juiced from the battery: if it's bad the battery juice all the board, even when switched off, and the battery goes low fast).

just to clarify: i turn on the machine with the advance buttons pressed (and auto-up?), this brings me to the bookkeepings (what's the use of depressing the advance button, the machine comes up in bookkeepings anyways?!?). from the bookkeepings screen, o turn off the machine, press down the middle button to manual-down (do i have to keep it pressed or is it ok if it "locks" in?) and turn the machine on again? i'm a little bit puzzled as you can see

This request was only to avoid other sources of problems to the board: i wanna see if the board reports no error at all when selftesting.
Well, try this path: depress the avance button, turn the machine off, then on THEN keep "manual up" depressed for more than 3 seconds. This should (but, as always, i refer to joust) let you see the RAM/ROM tests, CMOS RAM etc. When i had the problem of bookkeeping always coming up, the machine also reported a CMOS RAM error that, possibly, is the cause (or one of the causes) of the problem.

PS: Paperboy and PunchOut!! are both at my father place