Paperboy questions

[shardian]

Where is the test point on the ARIII?

I checked the voltage directly in the molex plug from the big blue. I was under the impression the voltage would be significantly lower if Big Blue was bad - not almost 5 volts higher.

 

[shardian]

I dug out my spare power brick from the garage. I was thinking about trading the big blue from it into the Paperboy's secondary big blue spot. If that is indeed the problem, it would show and then I would be happy to order some big blues.

 

[djw90]

Where is the test point on the ARIII?

I checked the voltage directly in the molex plug from the big blue. I was under the impression the voltage would be significantly lower if Big Blue was bad - not almost 5 volts higher.

Set your meter to 20v. black will go on the metal tab marked GND, its on the very top right hand side of the ARIII board. Red will go on the metal tab marked +10.3v. It is located just left of the J6 molex connector, on the ARIII board.

I had the same white screen you did. My +10.3v only tested +1.9v. I also took a reading on the top of the screws on the Big blue I could get to. It ws also reading 1.9v.

So I switched that Big Blue. still did not fix it. So I took out power block and replaced the other Big Blue on the power block. Fired right up.

 

[shardian]

I don't see why using the test point or measuring directly at the blue would give me different results than measuring directly from the unplugged molex connector. I'll do it anyways though. I have a spare untested power supply that I have cleaned up. I think I will swap it in this evening.

 

[djw90]

I have got different readings on connectors before. and its a check that your other reading was correct.

 

[shardian]

All the fuses check fine. One fuse and wiring is completely missing from the fuse block, but I just assumed it wasn't necessary for paperboy. It is present on the Champ Sprint Power block I have as a spare.

 

[djw90]

All the fuses check fine. One fuse and wiring is completely missing from the fuse block, but I just assumed it wasn't necessary for paperboy. It is present on the Champ Sprint Power block I have as a spare.

Let me go look at my block. Dont think im missing a fuse. I know my asteroids deluxe block is like that.

 

[djw90]

Here are some pics of mine. I have 6 fuses total, including the one in the black fuse holder. Also I need to read back thru this thread. Have you tested the +5 tab on the main pcb, and the +5 tab on the video pbc?

 

[shardian]

I haven't tested any of the 'tabs'. The only tabs I saw on the ARIII were +SENSE and -SENSE. I guess I didn't look close enough. +5 on the CPU is fine, because it is supplied by the switching power supply. I tested for +5 on the video pcb directly on the input connector coming from the ARIII. Didn't test for -5, because there is no -5 supplied by J13 to the video PCB.

IIRC, mine is missing F3. The fuse and the wiring is gone. Does that have something to do with the switcher being used to power the CPU board?

 

[djw90]

I think I have the same set up. I have a switcher that is used for +5.
There is a +5 tab and a ground tab near the top of the main pcb.
There is a +5 tab and ground tab near the bottom of my video pcb.


My +5 tab on the video board was not getting anything on it. Now after new big blues im reading 5.14 on that tab. Well just a few things to try.

If you find that the ARIII is causing the problems. I found someone that rebuilds them for 15 bucks.

I will have to look at manual to see what F3 does.

 

[djw90]

On page 54 of this manual, it shows the exact PS thats in mine, with all the fuses. Still looking to see what f3 does.
http://arcarc.xmission.com/PDF_Arcade_Atari_Kee/Paperboy/Paperboy_TM-275_1st_Printing.pdf

 

[shardian]

On page 54 of this manual, it shows the exact PS thats in mine, with all the fuses. Still looking to see what f3 does.
http://arcarc.xmission.com/PDF_Arcade_Atari_Kee/Paperboy/Paperboy_TM-275_1st_Printing.pdf

Yeah, but in the parts list it doesn't spell out the all of the individual fuses. I've been looking in the schematics too for F3, but not having any luck.

 

[2600]

F3 is on sheet 2B

 

[djw90]

Yeah, but in the parts list it doesn't spell out the all of the individual fuses. I've been looking in the schematics too for F3, but not having any luck.

I will keep looking to. I assume unless someone just threw in a different Ps to sell it, that its prob not an issue. The main thing I would like to see is a direct reading on the -5v tab of the video board, and the 10.3v on the ARIII.

 

[shardian]

I'm looking at the main wiring diagram, and there is no -5 anywhere. Where are you getting that?

The power brick sends +10.3 via big blue to ARII. It sends 36VAC straight from a transformer also.

The ARIII sends +5 and +15 directly to the Video board. It also sends +SENSE and -SENSE, but I'm still not clear what those are. It sends +15, -15, and +10.3 directly to the CPU, but the 10.3 is apparently just a safety check if I interpret "Power OK" correctly.

 

[djw90]

I'm looking at the main wiring diagram, and there is no -5 anywhere. Where are you getting that?

The power brick sends +10.3 via big blue to ARII. It sends 36VAC straight from a transformer also.

The ARIII sends +5 and +15 directly to the Video board. It also sends +SENSE and -SENSE, but I'm still not clear what those are. It sends +15, -15, and +10.3 directly to the CPU, but the 10.3 is apparently just a safety check if I interpret "Power OK" correctly.

I will have to look at the manual when I get home. Look at the test tab on the bottom of the video pcb. it might be +5. there is a test tab and a ground tab right next to it. take a reading there.

Ok just look at it online its +5 sorry for the confusion.

 

[shardian]

Here is what I did last night:
- replaced power supply brick (no change)
- took blue out of old power supply and replaced the secondary blue with it (no change)

No matter the arrangements of the big blues, I always get the same 15.3 or so volts on the 10.3 test lugs of ARIII, and nothing at the +5 test lugs of video pcb. I think I can safely rule out the big blues being a problem.

I still have no clue why I am getting 15.3 volts on the 10.3 line. It is debatable whether that really matters - well at least Wade was SUPPOSED to post that in this thread. He told me in an email.

Since the ARIII is still putting the proper 15 volts to the video pcb, I am considering just replacing the switcher with a bigger one and feeding both pcb's the +5.

I need to hunt down the +5 regulator on the ARIII and test it. Anyone care to give guidance on testing this LM305 part?

 

[shardian]

Side note: discharging a big blue is AWESOME!!! I'm actually quite glad I remembered to do that before messing with it. I would have hated to do that with my hand. Ouch!

I told my wife that I plan on discharging one on April fools in front of people and pretending it knocked me out.

 

[djw90]

Here is what I did last night:
- replaced power supply brick (no change)
- took blue out of old power supply and replaced the secondary blue with it (no change)

No matter the arrangements of the big blues, I always get the same 15.3 or so volts on the 10.3 test lugs of ARIII, and nothing at the +5 test lugs of video pcb.

No +5 on video board?? That is not good. Not sure if 15.3 on 10.3 is a issue, maybe someone else can answer that. If your ArIII board needs rebuilt. PM me.

 

[WadeLanham]

I still have no clue why I am getting 15.3 volts on the 10.3 line. It is debatable whether that really matters - well at least Wade was SUPPOSED to post that in this thread. He told me in an email.

Boohoo! That's right, I'm pretty sure some of my non-5v voltages were extra high on my Missile Command AR2, and it has been running fine for years. I think I tested it unloaded, so maybe the voltage drops when it IS loaded? For something like audio, does it really matter? Probably not... Or just pull that one wire if you are afraid it will burn something up and it isn't absolutely necessary for the system to run.

Since the ARIII is still putting the proper 15 volts to the video pcb, I am considering just replacing the switcher with a bigger one and feeding both pcb's the +5.

This is what I'd recommend. This is the same config as 720, right? It doesn't have to be permanent. But getting the game running or booting in some manner is the first step. You can always put it back to stock later if you really want to.

You can borrow my extra 720 harness if you want (or maybe keep) just to test your PCB's with a single switcher. You can also steal my extra "known good" Big Blue.

Wade