phat: Do you know what the readings are supposed to be on the dmm?
Zobert: that is why we have not had a party this year
phat: Likely it's something like 1.7 volts or somesuch.
Zobert: yup know what they should be, but do not know what to set the DMM to
Zobert: too (SP?)
phat: set it to DC at that point.
phat: I'm sorry I was preoccupied.
Zobert:
http://i.imgur.com/Tjqg9.jpg
Zobert: the DCV right off the center to the right?
phat: yes
Zobert: ah
Zobert: those readings were really messed up
phat: I think the AC setting may actually work in this case, too.
Zobert: fluctuating
Zobert: yeah some pinball switch that shit
phat: Well, then you got a bad transistor, it sounds like.
Zobert: I just replaces the bad transistors on the main power driver board
Zobert: might of fried the ones on the daughter board I was working on
phat: Odds are, one went bad and the whole thing cascaded.
Zobert: will hit them with the ohms to see if they still good
Zobert: replaced all of those as well
phat: Hmm.
phat: Well, then, you've got another problem.
Zobert: seems I keep replacing components and maybe messing them up
Zobert: all my shit is wired correctly
phat: Have you tested the resistors that go to ground?
Zobert: yup cascaded
phat: Have you replaced the capacitors?
phat: Especially the power caps.
Zobert: there is a ground braid
Zobert: I am in over my head to be honest
phat: Well, this is how we learn.
Zobert: le
Zobert: sigh
Zobert: true
phat: I use a particular database at work and I'm easily one of the most experienced people in the world on that thing.
Zobert: replaced all caps on the daughter board
phat: I learned a new trick today.
phat: Or I should say, "relearned".
Zobert: and lots of resistors
Zobert: ooooooooo learn
phat: Have you tested the resistors
phat: ?
Zobert: before, replaced a few
phat: Ok.
phat: Test them in circuit, with no power.
Zobert: I totally fucked up and put a transistor where a voltage regulator should of been
phat: Also, check for shorts in the board itself.
Zobert: I do not know where to check
phat: Yeah, that could wreak all sorts of havoc.
Zobert:
http://forums.arcade-museum.com/showpost.php?p=1321918&postcount=4
Zobert: Well, now that I've looked a the diagram..... we've got a problem. U6 should be a 7805 voltage regulator and not a TIP102 transistor. They use the same case design, but are very different parts. Definitely should NOT have a TIP102 anywhere on that board.
phat: The most important thing to check in a circuit is the path to ground.
Zobert: I do not know where my ground is :-(
phat: That's where most problems occur.
Zobert:
http://farm5.static.flickr.com/4128/4948140073_e74a013dcf_b.jpg
phat: You can find the ground path pretty easily.
phat: In fact, it may be labeled on the board.
Zobert: up on J1 on the top right I think there is one
Zobert: so should check that
Zobert: I think that is what the guy helping me is going towards
phat: Do you have a schematic of the circuit?
Zobert: makes sense now
Zobert:
http://beerorkid.com/stuff/Williams_1991_The_Machine_Bride_of_Pin_bot_Full_Manual.pdf
Zobert: will get page number
Zobert: it is fucked though
Zobert: bad scan
phat: Ok, you need to learn how to read the schematic.
Zobert: my hard manual is much better
phat: Have you learned that?
Zobert: been doing OK on it
Zobert: also following wires
phat: What are J2 and J3 on that board?
Zobert: led me to the right transistors to replace on the main power driver board
Zobert: will check
phat: By the way, dude, I'm just gonna say this right now, this woman I sent the note to seems amazing.
phat: Oh shit, that diagram tells me what's on that board.
phat: I'm sorry I didn't notice.
Zobert: sweet on the lady
phat: Ok, so the js are just jumpers to other boards.
Zobert: j1 is where the power connects
phat: Which I should have known.
Zobert: it is just power
phat: Ah!
phat: Ok.
Zobert: j2 I am not sure
phat: I wouldn't be shocked if J1 had a short.
phat: What's the game doing?
phat: Are you getting nothing or is it just acting erratically?
Zobert: I think J1 also sends the info for the board too
Zobert: seems J2 and J3 go to the lights
Zobert: it is a board that controls flashing lights to the helmet
phat: Yeah, there seems to be a "data" deal on there, and a clock signal.
Zobert: they take many diff patterns
Zobert: absolutely nothing
phat: nothing.
phat: ok, well, that might be complicated, but it's likely not.
Zobert: they were really weak before, and I put 3 LED lights (that take way less power) in the helmet and they all died
Zobert: nothing at all now
phat: Oh really?
Zobert: on the forum they think it might be power supply problems
Zobert: we have not gotten into that much
phat: Were they bulbs before?
Zobert: so I figured it was on the power driver board. Replaced all the transistors that correspond to them, still nothing
phat: Or LEDs?
Zobert: that is what I did today
Zobert: I could of still fried a IC chip
Zobert: they were incondecent bulbs before
Zobert: much higher draw
phat: Ah, ok, what did you do when you tossed in the LEDs?
Zobert: but the LED bulbs I put in were polarized
phat: There's your problem.
Zobert: I do not think that would matter, they would just not light up up if inserted the wrong way
phat: Or were the LEDs designed to replace bulbs?
Zobert: those bulbs are pulled and incandescent are back in
Zobert: yup
phat: ok
phat: well, maybe that's not the problem.
Zobert: because LED are brighter, use less power (reducing strain), and never burn out
phat: Right
phat: hmm
Zobert: but it was strange that putting those bulbs in was what killed the whole set of lights
phat: That is strange, yes.
Zobert: they worked before, but were weak as hell
phat: OK, so, I think maybe we can isolate this problem.
Zobert: I will prob pull the chase light board, check with ohms all the transistors (diodes?) , and replace them if needed. And also replace the IC chips and go from there
Zobert: my problem is not isolating it
Zobert: Actually thinking about it now it must be the IC chips
Zobert: because my readings were so off
phat: That could be.
phat: You should test things in order.
Zobert: they flucuated like how the lights would blink
phat: ok, that's a good sign, actually
phat: So it's not the ICs
Zobert: it is a huge pain to follow the wires, but I am willing
Zobert: well maybe the ICs are not accepting the signal and working properly
phat: ICs don't fail very often at all, unless something really bad happens.
phat: If they're putting out lots of switching, then they're fine.
Zobert: I have put the DMM up on the lights that are supposed to work and nothing
Zobert: but I put a transistor in the place of a voltage regulator and blew fuses
Zobert: so I might of messed them up
phat: Yes
Zobert: I could still get readings from U1 pin 14, but they were strange. I know you do not know what that was, but it was a tip from a web friend
phat: I suspect you've got a power supply problem, now.
Zobert: I am thinking that too
phat: Ah, have you replace U1?
Zobert: have not, that would be my next thing I do
phat: Do it!
Zobert: still 14 pins to unsolder and resolder
Zobert: gah
phat: And, if you can, put a socket in there.
Zobert: I am good, but that will kill me
phat: Yeah, PITA
Zobert: yup socket
Zobert: holy shit you know your shit
phat: sort of, yes
Zobert: but this is one you should never have to mess with
Zobert: not sure a socket would be worth it
phat: I dig this shit to no end.
phat: Well, you may as well.
Zobert: you wanna come play?
Zobert: lol
phat: You're more likely to damage the IC when soldering it in directly, anyway.
phat: Put a socket in there.
phat: Saves a headache.
Zobert: will order some
Zobert: might as well
Zobert: although I feel like freeballing it
phat: You don't have to worry about getting the heat sinked when soldering, which is the biggest problem.
Zobert: ah
Zobert: makes sense
phat: yes
phat: Heat kills solid state dead.
Zobert: damn
phat: some guys socket everything
phat: transistors and even resistors.
Zobert: I would put all the effort on getting the old one out and then bend a bit of the legs for the holding
Zobert: solder well
Zobert: but I see the heat factor
phat: yes
Zobert: heat the component not the trace or solder
phat: plus, when your dealing with digital ICs, grounding gets weird when soldering directly.
Zobert: so it stresses it
Zobert: ack
phat: some of these chips can be touchy
