I noticed that square speaker grill right away. It's definitely not a factory piece. The 7-slot cut in a round shape is what you should expect to see.

Someone modified yours after the fact. You'll need to tear that entire front piece off and build a new one.

BTW, if you need a wood DKjr contron panel, there is a guy named hailrazer building reproductions on KLOV.

DK jr is an awesome game and machine. I'd totally make it a DK jr again. Simple as that.

Price is $250 for the vs and all games. If no one wants it all for that price, I will begin parting it out tomorrow. If it gets parted out, one of the coin boxes is already claimed.

Wow! That is a fantastic . Shame you are not closer to me.

my dislikes are almost everything made after 1986ish.

My lucky day! I was born before that.  ;)

That's cool, I read Engadget almost every day. That DK jr scratch build sounds interesting. You should post that progress here when you do it.

Welcome!

Ian,

I did find the C2 cap last night. It was located on the other PCB:



I couldn't see it until I cleaned the filth off the board!

I should have this whole power supply capped by the end of the week. Crossing my fingers this solves (or at least helps) my audio hum and siren noise.

you could wash it with water. I use the dish washer all the time. It does leave a slight residue behind but its easy to clean that up.

no soap, no added heat, no heat dry cycle on the dishwasher.

You can dry the PCB in the oven at 150F for 30 minutes to an hour.

Awesome tip. Thank you!

I'll report back on the C2 search. Thanks again Ian, you're the best!

Is there one PCB or two PCBs in the supply? I vaguely remember there being 2 PCBs. Check the other one.

I actually found  my copy of the manual and it has a cap map in it. I have never seen this published online so I will be scanning it in this week and fixing the instructions for that kit.

Yes, there are 2 PCBs when you open the power supply. I checked both PCBs last night looking for C2 and that is only one I could find. All the other caps I could find except that one. I'll give it another look when I am home tonight. The boards are filthy. I really want to wash them with some simple green and water but I have a sneaky suspicion that would be a bad idea. Even if I let them dry for a few days.

Hi Ian,

I'm about to cap my DK power supply and I was just checking out all the cap locations. I noticed that C2 on the board doesn't look like a cap. (See image below) Is that where I should really install the new C2 cap?

No worries whatsoever Ian! You've already been more than helpful. I think you're right. Something is not cutting off the sound and that is the siren noise. And the hum is probably a bad ground.

I'm gonna cap that power supply and go from there.

[I STILL have that annoying hum mixed with the siren sound in the background. Sigh.]

My sweet cap kits arrived. One kit is for the audio capacitors on the DK PCB and the other kit is the capacitors for a DK power supply. I just really love how organized your kits are Ian!





I decided to do the audio PCB capacitors first. In the image below, I have now replaced every single audio capacitor and transistor inside the red line. 16 caps and 7 transistors I believe



I then hooked the board back up into my DK, turned it on and....I STILL have that annoying hum mixed with the siren sound in the background. Sigh. The overall sound of the game might be sliiiighly better. But maybe my ears are just playing tricks on me now. Good news is that I didn't make it worse...but I certainly didn't outright fix it.

The last place I have not really poked around is the power supply. So, I'll be putting a new cap kit in the power supply next. Might as well, its 35 years old and has never been capped.

If the game PCB wasn't there and its humming then it could be from the amp.

I have been trying to get my hands on a nintendo that hums badly so I can document the issue.

If you haven't replaced your b+ cap on your sanyo, you should do so.
My current belief is it has something to do with the lack of grounding on the speakers and the input wire.
Try disconnecting the audio input wire from the audio amp. M ake sure there are grounding wires from the monitor and I think even the speakers should have grounding wires. 100% make sure you have a ground prong on the plug and it is VERIFIED to be connected to the monitor. This is a switching power supply. Ground is even more important here than it is with a linear power supply.

This is very good feedback Ian thank you so much. I used one of your Sanyo Kits and completely re-capped the monitor including the B+ cap. The picture looks fantastic now.

I know the speaker itself has a ground wire. However, come to think of it, I'm not sure the monitor frame is grounded? The power plug for the monitor is only 2 pronged going into that outlet plug in the bottom of the cab.

When I first got the machine, the main power cord was missing a ground prong but I have already since rebuilt that with a brand new power cord.

If my new power supply cap kit doesn't help, then it's got to be a bad ground somewhere. I'm glad to cap the power supply though. I bet it has never been touched and at least I'll have some insurance.

I'll keep you posted!

Thanks Ian!

I just bought a power supply cap kit and DK PCB audio kit from you. I'll report back with my results!

One more update:

I don't know why this never occurred to me, but I turned on my DK cab without the PCB inside...and it STILL made the loud hum. That sounds like a a problem with the power supply no?

Aren't those capkits and the packaging awesome

They sure are! Ian's kits are the the bee's knees!

but it almost sounds like it isn't turning off one of the audio generators.

That's what I thought too. Apparently, the transistors were supposed to solve that problem. However, I only replaced Q4 and Q6 so far. (I wanted to tell if that fixed it)

So last night I replaced the rest of the transistors but have not officially tested it yet. We will see.

I also have a spare DK jr board arriving soon. I'll put that in and see if that board also has the buzz sound. Thanks again for your help!