Defender resetting with ram & rom failures. Starting from the beginning.

Thomas

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Defender resetting with ram & rom failures. Starting from the beginning.

I have the later set of boards.
This board set "does have the 4164 ram mod & battery mod".
The boards are fresh back from repair but doing the same stuff as when they were sent.

I have never worked on a defender before. I am also but a padawan learning to read the schematics correctly. I don't want to just go hap haphazardly trying to test stuff until I am sure I am doing it right.

Anyway I wanted to start from the beginning on this defender and make sure I have a rock solid linear power supply. This is what I gleaned from a set of schematics.

Are these TP values correct for this power supply?
----
TP1 5.1 VDC
TP2 +12.8 VDC
TP3 -14.8 VDC
TP4 +12.1 VDC
TP5 -4.9 VDC
TP6 Ground

Did I read it right? What are all the necessary steps to testing this defender power supply correctly?

Oh better snaps...
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http://arcadeparts.org/Machines/Williams/Defender/Boards/

Thanks for all your help!
 

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First off...

Don't measure it at the power supply. Measure it at the chips on the board as there will be some losses in the wiring and connectors.

Next, if the board were fixed but not all the wiring components you may have issues there.

RJ
 
Thanks RJ I guess I better read up on that a bit before I try it.

Here are my readings from the power supply test points only.

TP1 5.1 VDC My Reading 5.44
TP2 +12.8 VDC My Reading 11.82
TP3 -14.8 VDC My Reading -14.03
TP4 +12.1 VDC My Reading 12.62
TP5 -4.9 VDC My Reading -4.96

http://forums.arcade-museum.com/showthread.php?t=152793&highlight=defender+chips+test+point

I am over 5.25 on TP1 as suggested by Andy in this other thread. Which is not correct. I am also high on TP4.

How can I fix those issues or are they okay?
 
First off...

Don't measure it at the power supply. Measure it at the chips on the board as there will be some losses in the wiring and connectors.

Next, if the board were fixed but not all the wiring components you may have issues there.

RJ

+1


If you had the board repaired then must be a wiring problem or power supply!
 
Ok... Here are three if I am doing these correctly

C9
Ground (pin 16) and (pin 1) (-5vdc) 12.4
Ground (pin 16) and (pin 8) (12vdc) 5.01
Ground (pin 16) and (pin 9) (5vdc) 5.10

C20
Ground (pin 16) and (pin 1) (-5vdc) 12.2
Ground (pin 16) and (pin 8) (12vdc) 5.10
Ground (pin 16) and (pin 9) (5vdc) 5.13

C12
Ground (pin 16) and (pin 1) (-5vdc) 0.78
Ground (pin 16) and (pin 8) (12vdc) 5.10
Ground (pin 16) and (pin 9) (5vdc) 01.2

I had a ram failure 12 on my screen so we did that one last.

So what is the deal with this thing? Can anyone tell me why the readings are low on the C12 4164 ram? I have switched this ram out a couple of times and I still have nothing.

Man its tough trying to get those readings inside the cab. Is there a better way to get all the readings short of a test bench?
 
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Ok... Here are three if I am doing these correctly

C9
Ground (pin 16) and (pin 1) (-5vdc) 12.4
Ground (pin 16) and (pin 8) (12vdc) 5.01
Ground (pin 16) and (pin 9) (5vdc) 5.10

C20
Ground (pin 16) and (pin 1) (-5vdc) 12.2
Ground (pin 16) and (pin 8) (12vdc) 5.10
Ground (pin 16) and (pin 9) (5vdc) 5.13

C12
Ground (pin 16) and (pin 1) (-5vdc) 0.78
Ground (pin 16) and (pin 8) (12vdc) 5.10
Ground (pin 16) and (pin 9) (5vdc) 01.2

I had a ram failure 12 on my screen so we did that one last.

So what is the deal with this thing? Can anyone tell me why the readings are low on the C12 4164 ram? I have switched this ram out a couple of times and I still have nothing.

Man its tough trying to get those readings inside the cab. Is there a better way to get all the readings short of a test bench?

That is because the 4164s don't use the -5V or the +12V. Those voltages are only used by 4116 RAM chips.

ken
 
That is because the 4164s don't use the -5V or the +12V. Those voltages are only used by 4116 RAM chips.

ken

Ok progress...

C9
Ground (pin 16) and (pin 9) (5vdc) 5.10

C20
Ground (pin 16) and (pin 9) (5vdc) 5.13

C12
Ground (pin 16) and (pin 9) (5vdc) 01.2

So only these readings are relevant?
Should I have power at the other two test points if I have 4164 ram?
What are you trying to tell me Ken? lol

So C12 is low big time and I have good power. I guess its time to trace that pin back see how it got damaged.
 
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I'll try to explain this with a minimum of hand waving and drawing pictures in the air.

4116s use 3 voltages: +5V on pin 9, +12V on pin 8 and -5 on pin 1.

4164s use 1 voltage: +5V on pin 8. Pin 1 is not used and pin 9 is address line 7 which is not used and is typically tied to pin 8 (+5V) to avoid randomly switching between the banks of RAM (not a good idea).

If you are seeing +12V on pin 1, it may be that the adapter was not made correctly. verify which line on the original power input is +5 and which is +12. The original power connector should be
Pin Voltage
1 N/C
2 Ground (BLACK)
3 Ground (BLACK)
4 Key - N/C
5 +12V Regulated (this would go to the RAM) (GREY-YELLOW)
6 N/C
7 +5V Regulated (GREY)
8 +12V unregulated (goes to CMOS memory protect circuit)(GREY-WHITE)
9 -5V Regulated (ORANGE)

Coming out of the adapter should be:
1 N/C
2 Ground
3 Ground
4 Key - N/C
5 +5V Regulated (this would go to the RAM pin 8)
6 N/C
7 +5V Regulated (GREY)
8 +12V unregulated (goes to CMOS memory protect circuit)(GREY-WHITE)
9 N/C

If you are seeing this from the adapter, then check the continuity between pin 8 on each RAM chip and pin 5 on the header. If you plug just the adapter (not the power connector from the power supply) you should have continuity between pin 5 and pin 7 of the input (the +5V is normally tied together in the adapter) and pin 8 and pin 9 on each RAM chip.

If you are not seeing that, then there is something wrong with the power traces through the board.

ken
 
Im still not clear on this...

How the heck am I getting 12.4vdc and 12.2vdc on pin 1 of my 4164's which is -5vdc only on the 4116's? Is that frying my 4164's or because its on pin 1 it makes no difference?

http://arcadeparts.org/Machines/Williams/Defender/Boards/

YOU HAVE WIRED YOUR ADAPTER WRONG, THAT IS HOW!

Should be like this:

1J1

1 - NC
2 - GND
3 - GND
4 - Key
5 - +5vdc
6 - NC
7 - +5vdc
8 - +12vdc
9 - NC

Dok
 
Did you get a good look at that adapter?

http://arcadeparts.org/Machines/Will...fender/Boards/

There are three pictures of it. The way its wired still does not explain the 12v on pin 1. Granted it is a little different.

5v goes in pin 7 then loops out to pin 6 "thru the board". Then the jumper from pin 6 puts 5v back in pin 5.

I am gonna make another adapter just like the picture on robo 2084 but it still wont solve the 12v issue.

I swear I think Cathy messed up on those pin 1 readings on the 4164's...

This machine came to me the way you see it. I haven't wired a thing yet.
 
My apologies Billy, the adapter is wired wrong. (period)

Take power readings with the adapter not connected to the cpu board and post what you get coming out of the adapter and you will understand where your 12vdc problem is at.
 
Dave you did not need to apologize. I have no issues except this damn defender!

I just wish we had time to retest tonight and make a new adapter. Cathy is like hell no we are going Christmas shopping bigboy! No time for the arcade tonight. lmao...

Now if she would bring on dinner cause its getting late!
 
Dave you did not need to apologize. I have no issues except this damn defender!

I just wish we had time to retest tonight and make a new adapter. Cathy is like hell no we are going Christmas shopping bigboy! No time for the arcade tonight. lmao...

Now if she would bring on dinner cause its getting late!

Golden Rule: If Momma ain't happy, nobody is happy!

Very important that you remember that Billy.:D
 
This is with the adapter plugged into the power supply only

1 - NC -
2 - GND -
3 - GND -
4 - Key -
5 - +5vdc -----> 248.2
6 - NC -----> 246.3
7 - +5vdc -----> 5.79
8 - +12vdc -----> 13.42
9 - NC

Holy Shit
 
This is with the adapter plugged into the power supply only

1 - NC -
2 - GND -
3 - GND -
4 - Key -
5 - +5vdc -----> 248.2
6 - NC -----> 246.3
7 - +5vdc -----> 5.79
8 - +12vdc -----> 13.42
9 - NC

Holy Shit

Check the scale on your DVM when you check pin 5. If you have an auto-ranging DVM that is probably milli-volts. Which would indicate that pin 5 is not connected to pin 7.

Your +5V (Pin 7) is also too high. It should be +5.00 +/- 0.1 Volts.

ken
 
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Your correct ken those pins 5 and 6 are connected to nothing until the adapter is plugged into the board. Just like it says in the text under the diagram on the robo 2084 site. The cpu boards 5v loop feeds that adapter 5v for pin 5 thru pin 6. If that makes sense and there is no 12v on the adapter except pin 8 where it should be.

That's why I wondering about the 12v on pin one and wondering if that read was correct. I just haven't had time to get back to it yet to retest the rams. I half to have Cathy do those for me. It's to painful for me to mess with. It hurts my neck and back. I don't want to ever pop my neck again. That's freaking scarey!

Guy's

What would make the +5 go high? It has been really high from the start of the thread. When these old supplies go high like this whats the best recourse. It looks like most of the components are new.

One of the bridges is a tad higher than 600 as dokert spoke of in his video.

http://s291.photobucket.com/albums/ll282/dokert/Testing Video/?action=view&current=100_3099.mp4

But its only high on one cheap meter (cen-tech). On the other cheap meter (cen-tech) it just below and on my (craftsmen) it is below 600.

If I remember correctly it's the small bridge AL156 in the vid.

----

Quote Dokert...
Replace Resistor R2 with a 5K pot, and your +5vdc will be adjustable.

----

Would radio shack have a 5k pot and would you know what the part# is so I could by the right one?
 
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