Congratulations, that means you have already completed the most difficult soldering tasks.

The sound quality should be quite good. That means if you hear some kind of noise or distortion than something is not right. A bit of static is normal of course, but it should only be audible when you turn up the volume without playing any sound. This will vanish if you later decide to use the digital volume control, because then the audio amp will be muted when no sound is played.
With the old boards you sometimes had quite some distortion depending on lamp and display activity - this should also be gone now.

Sorry, but I don't see it, can you post a close up of the connectors? Basically your Millionaire should have the same connectors as my Pinbot and I didn't have any problems.

You're soldering faster than I'm able to reply.
For the next step you need to use the normal APC.ino software instead of the Soundcheck, because the latter doesn't support the switches.

I'll check for the BOM issues. Thanks to you there will be a new BOM coming soon with all parts having Mouser ordering numbers, but until now it's just in the AmokWork branch. I'm going to merge it to the master branch soon, but first I have to implement the new version of the USB API.

Glad to see you're making so much progress. You have already been of great help for this project.

Could also be the old volume control knob. As you now have control of the switches, you could try to unplug the connector for the old volume control and use the digital one instead. For this you have to enter the System Settings then press Advance until you reach 'Speaker Volume'. The System should play the MUSIC.BIN file and you can increase the volume by pressing the 'Game Start' button.
When there's still some crackling take a look at your speakers. I didn't realize the speaker of my JL was damaged until I tried the APC in this machine. The speaker was still good enough for the old Sys7 sounds, but it sounded lousy when the APC was playing real music.

Ah OK, I thought you were referring to the connectors of the APC. The Sys11 Sound configuration was quite messy, because they changed it several times over the years.

When does this happen? Every switch being triggered should leave a message in the 'Switch Edges' test.

It has a temp sensor, so it should protect itself. Try it again when it has completely cooled down. Probably something is wrong with your digital volume Control, so switch the setting back to zero and use the knob for starters.

That's a bad soldering joint at U14.

Can you make a photo of this? It it only in the lower display row? Then you have to change the Display Setting to Pinbot.

This is probably not a big deal, but the problem is that I'm busy for the next 6 hours at least. Don't worry - we're going to fix this later.

Hi Lance,

No problem, I'm back, slightly drunk but hopefully still helpful.

That's strange. Like I wrote the IC has a temperature protection, so it won't die from overheating. That means if it's really blown than something has killed it and we should find out what it was before we put the next IC at risk. Most probably it's a short somewhere.
Let's first measure your speaker. Please unplug the speaker connector from the APC (10J2) and measure the resistance of the APC pins and the speaker cables to GND. None of them must have a resistance of less than 1Kohm to GND.
Then try whether the amp IC still get's hot with the speaker connector and the volume connector (10J4) removed and the digital volume set to 00.
Also check the voltage at pin 3 of the TDA. This is the volume control, which means the voltage at this pin should be 0V when the voltage control is set to 00 and then rise when you increase the setting until it reaches 5V at a setting of 255. After that, set the volume setting back to 00 and connect the manual volume control (10J4). When you turn the knob, the voltage should vary between 0V and 5V but it must never exceed 7V.
Also note that the manual volume control must always be unplugged when using the digital volume control, but even if it's not it shouldn't damage anything.

This is due to a wrong display setting. The default setting of the APC is for both rows having alphanumerical displays. That means the APC treats your lower display row like alphanumericals which leads to these artifacts.
It's the first entry in 'System Settings', the default is '4Alpha+Credit', press 'Start' to change it to 'Sys11 Pinbot'. After that proceed to 'Exit settings' which should write this setting to your SD Card. After that the artifacts should be gone (if not do a power cycle).

To be continued ...

That's good news, because it means that it's just your volume control causing the problems. Apparently the control voltage is stuck to the maximum volume which leads to distortion and overheating of the amp. Please unplug the manual voltage control (10J4), remove R70 and measure the voltage again. If it's still stuck to 5V then you have a short to 5V somewhere near C4, R76, C10 or even at pin 3 of the TDA itself. If it's close to 0V now, reconnect 10J4 and you should be able to use your sound with the manual voltage control. In this case check the soldering joints of Q5 and R68.

Look good to me. The lower display row of your Millionaire has only numerical displays and that's how it looks when the APC tries to show characters on them. But you're only going to see this in the settings, because in the game mode the lower row is only used for numbers.

The next steps involve the use of your logic probe, so let's first make sure that we're talking about the same thing. Your logic probe should have a GND and a supply cord, each with a clamp. A tip of course and two LEDs (probably red and green), one for high and one for low logic level.

Unplug connector 1J1 of the APC, then connect the supply clamps of the logic probe to +5V and GND on the power board of your Millionaire and power it up - both of your LEDs should be unlit as well as the Player 1 and the Player 3 display. Now try all pins of connector 1J1 with your logic probe. Both LED should light up which means that the pin is toggling. I expect that to happen at every pin except pin 7, as this is the one responsible for your leftmost Display column. If no LED is lit at this pin you have a bad solder joint at your connector, if only the high level LED is lit, the bad joint is probably at pin 2 of U14.

Try the logic probe also on all pins of the Solenoid Drivers (1J11, 1J12 and 1J19) with the connectors unplugged. Both LEDs should stay off, but as you said all coils at one solenoid connector were being activated I expect the low Level LED of your logic probe to be lit at these pins. It would be important to know whether this is the case for all pins of all solenoid connectors or just for some of them.

Cheer up - we're making progress. I'm confident you're Millionaire is going to work soon.

Frank

Edit: fixed some typos

OK, I've attached a pic of the TDA pinning, because we should be very clear on what pins we're talking about. I also added a picture to the docs which should help to identify the connectors:

https://github.com/AmokSolderer/APC/blob/master/DOC/PICS/APC_Connectors.png

For the following test you should unplug the speaker connector (10J2) in order to protect the amplifier.

As your problems started with the digital volume control it's probably a good idea to disconnect it. As mentioned above you can do that by removing R70 on the APC board. After that reconnect the volume connector (10J4 or 1J16 for Sys11), power up and look what happens to the voltage at pin 3 of the TDA when you turn the old volume control knob. Can the voltage be smoothly adjusted this way or do you read sudden jumps to 5V?
If this looks good you should be safe to try the sound again. For this you should adjust the volume to a low level (low voltage at pin 3) and reconnect the speaker connector. Now play some music and try if the manual volume control works.
Depending on your results we can decide how to proceed.

Good luck

Frank

TDA_pinning (resized).PNG

Sounds completely correct and I might be getting paranoid, but I've attached another picture anyway - just to be very sure.
Please check the GND of your multimeter also, the 'Solenoid GND' connector of the APC is a good place to connect it to. Pardon my scrutiny, but you can get all kinds of strange results if the ground connection is bad.

However, if all the above is correct and the voltage at pin 3 of the TDA is still as you've described then please measure the same at pin 2 of the voltage control connector (10J4). Can you now use the pot to control the voltage?

TDApin2 (resized).JPG

I guessed so

But the result of all of this: you have a break between both pins and it is probably a loose connection at R76 - Please check the solder joints.
To check the connectivity, disconnect the volume connector J4 again, do not power up the board and measure the resistance between pin 3 of the TDA and pin 2 of J4. When everything is right, the resistance should be 300K.

Just like this or did you resolder it?

That measurement is fine indeed.

But the sound has worked before, so we're dealing with a loose connection which means it can be OK in one second and then gone. You're close, it has to be there somewhere. May be try to apply some pressure to the resistor and remeasure it. Or just try to resolder it and then check again if you're able to control the voltage at pin 3 of the TDA with the pot (reconnect J4 of course

I don't think so. For some reason you cannot control your voltage at pin 3 any more. From the voltage readings you get it sounds like the pin is not connected and floating, which would result in random volume levels with a strong spike after turn on (which is what you see). As long as we're not able to adjust the pin 3 voltage the amplifier cannot work properly.

Could you please measure the voltage between both pins pf R76 with the same setup as above and see if the voltage changes when you turn the pot?

Oh yes it is, but that's not your fault. You just have one nasty problem there.

However, you should be able to mute the sound with the pot, so something's still not right there.

And let me rephrase my latest statement. Of course it is also possible that the pin 3 of the TDA itself is faulty and causing a current which spoils the voltage at this pin. But I don't just want to replace it because these pins don't die easily and I don't want to put the next amp at risk. We have to find the root cause first.

So please disconnect your speaker again, then try to unsolder pin 3 of the TDA and lift it until it has no electrical connection to the pad any more (I know this wont be easy). Then try the standard measurement again (adjusting the voltage with the pot), but measure the voltage at the pad now being empty, not at the lifted pin.

With pin 3 being lifted? That would mean the TDA is not damaged.

OK C10 is the last device left, please remove it and try again.

Do I get you right that with pin 3 lifted you get the correct voltages on the outer pin of R76, but the same strange voltage readings at the inner pin of R76?

Hi Lance,

it's still getting more strange. Either we have some misunderstanding or things are really weird on your board. To prevent the former let me just summarize what we did and what the results were. I have attached a picture of the circuit we're dealing with. As you can see this is nothing fancy.

At the beginning you removed R70 to disconnect the digital volume control. After that it's just the pot, a bit of RC filtering and the input pin of the TDA. For clarification I have named the input side of R76 (the pin closer to the rim of the board) as 'Node A' and the other pin of R76 (which is connected to pin 3 of the TDA) as 'Node B'.

Our goal is to use the pot to control the voltage at Node B, but for some reason you can only control the voltage at Node A, but not at B.

At first you checked R76 to ensure that the electrical connection between Node A and B is OK. You used a multimeter to measure the resistance between A and B and found it to be in the range of 300K which is fine. You even measured this resistance between pin 3 of the TDA and pin 2 of J4 to check the corresponding board traces also.

As the voltage at Node B was different from Node A and R76 was fine, it had to be a current through R76 causing a voltage drop at this resistor. But this current has to come from somewhere so we tried to exclude the possible candidates. First you lifted pin 3 of the TDA and after this didn't help you also removed C10.

However, when I got you right then all of this didn't help, the voltages at Node A and Node B are still not equal, right?

That means we still have a voltage across a resistor and according to ohms law this requires a current. But since you have removed all electrical connections except the resistor itself there should be no path left for the current to use and that means there has to be an unwanted current path from Node B to somewhere else.

Please check the pads of R76, C10 and pin3 for possible shorts. It might be a barely visible droplet of solder, so try to use a magnifier. And be sure to check the pad of pin 3 also on the top side of the board, may be something is hidden there. Try to measure the resistance between Node B and it's neighbours as well as GND, +5V. None of these values should be less than the value of R76, because this should be the only way out for the current.

Even though it is extremely unlikely, it might also be a board manufacturing problem. We know, that the design and layout is working, because several people are using it already, but it might be an issue with your particular board. Therefore please take a close look at the board traces also.

I'm afraid that's all I can do for you from the technical point of view. If all of this doesn't help we can try to setup a Skype meeting to look together.

Good luck

Frank

APC_Audio (resized).png

Yeah, but that's normal with the old pots. In the end I would recommend to use the digital voltage control anyway, but before we have to find out what causes your problems.

Like I wrote above, the critical point is that you have measured different voltages at Node A and Node B. This can only have two possible reasons, a damaged R76 or board trace (which is not the case according to your measurement) OR a current through R76.

Let's assume there is an unwanted current path to Node B and it's so well hidden that you're not able to find it. Then let's try to avoid Node B by building a new one. Just put R76 vertically on the pad belonging to Node A without the second pin touching Node B, do the same with C10, solder it vertically on the GND pad without the second pin touching Node B. Then simply connect the lifted pins of R76 and C10, power up and measure the voltage at Node A and the two connected lifted pins. If your problem has something to do with the board trace then you should now be able to control the voltage at the connected lifted pins with the pot, because we avoided the trace completely.
If it works you can also lift pin 3 of the TDA again to disconnect it from the pad and use a wire to connect it to the lifted pins of R76 and C10.

I have to study the schematics to see if that's possible. I never had any problems with my Pinbot though, which is the same generation as your Millionaire. However, 10V at the volume pin could possibly fry the amp, as the max voltage at this pin is specified with 7V.

I wouldn't do that, because it'll cost you some audio quality. Just disconnect the pot by unplugging J4 and just use the digital volume control instead. It cannot cause any damage, as it applies 5V max. I use a volume setting of 35-40 and never got any problems. The worst thing to happen is that the amp gets too hot and mutes the speaker, but it's not giong to be damaged by this. If this happens, you can just apply a heatsink to it's back. I never had the need to do it, but that's the reason the amp is sitting at the rim of the board.

Concerning your solenoid issues. Are all three solenoid connectors (J11, J12 and J19) affected or is it only one?
If you don't want to use your logic probe as I described in the assembly help wiki you could also use your flippers to check. There is probably an extra two pin connector for pin 1 and 2 of 1J19 (APC connector 2J12) - this is for the flippers. The advantage is that they wont suffer from being acitivated permanently, so you can use them to probe whether the coil drivers of a certain connector are powered or not. Just connect the small connector to the one you want to probe and try the flipper buttons, if the coil driver is active then the flippers will work.

I have just finished the MPF Tutorial and it works well with the APC. We still have to update the display and sound commands in the API, but lamps, switches and solenoids are already doing well.

No Digikey, Mouser or Reichelt in Switzerland?

Depending on what pinball generations you want to use the APC with, you could cut the price by not assembling all Molex connectors. In the BOM some connectors are marked with 'Only needed for Sys9 - Sys11' or 'Only needed for Sys3 – Sys7', which means that you don't need these connectors if you don't want to support that kind of games.

Additionally you could check the shipping costs of Reichelt.de which is the cheapest electronics retailer I know of. This would have the additional advantage that you could use my Reichelt shopping list. I think Snux also used Reichelt, because they were still cheaper than the rest even when shipping to the UK. Alas, they don't sell all the required parts, so you still have to order the Molex connectors, the 74HCT154 and the 74BCT760 somewhere else. And the Arduino of course, but this you can order from china.

Concerning the boards you could ask the dutch guys from post #88 to sell one to you.

System7 works very well and if you intend to program the APC natively, there is even a game software available for Black Knight. The effects need some polish and you have to add the sounds by yourself, but the game itself is working quite well.
As mentioned on my GitHub page, I didn't use the original displays, but a self made alphanumerical type. This means that the text messages of the BK software won't be readable, but numbers like points will be shown correctly.

Do you know https://lisy.dev/ ? It's a replacement MPU for Gottlieb pinballs. Might fit better in your Tag Team than the APC.