Sega Saturn recap DONE!

 The TL;DR of this is check the power supply even if it turns the console on...that being said...

This was about a week's worth of work to finish up, simply because I had to order another cap kit to complete it. 

The recap project was a Japanese Sega Saturn that I got. It powered on, but no video came on. Initial internet scouring lead to recapping the whole main board. So, along with the other cap kits, I ordered it for the specific board revision I had. When I finished the Game Gear recap, I started work on the Saturn.

This is pre-recapping. Nothing really stood out for leaking caps, but I figured that I should just redo it anyway since most capacitors from the 90's were bad, and this board might just be a ticking time bomb of exploded cap goo.

I tired to use the same SMD desoldering method Voultar uses, utilizing the hot air rework station, but this proved to be a bear of a job. The fist cap I tackled took what seemed like forever to get off. At that point, I just used my soldering station to heat one side of the cap, tilt it just enough to remove the connection from the board, and heat the other side to remove it completely. 

There were 2 caps that , when removed, I had lifted some of the trace off of the board, but not completely ripped it off from the board. I verified that the traces still had connection using my multimeter. After verifying, I used a drop of super glue to hold the traces down. After the glue dried, I proceeded to recap the board.

Here it is, in all it's recapped glory. I temporarily put the drive posts up to test the Saturn after the recap. After getting all the connections in and getting the power cord and the A/V cable set up, I powered it on and...

...nothing...

Still a blank screen. Power indicator is still on, but no video. At this point, I thought those 2 lifted traces are the culprit and started to think of secondary connections that I can solder to. I was about to give up until my brain clicked: maybe it is the power supply?

I took my multimeter out and checked the connections on the power supply, still powered on. 

The black wires were ground.

Orange wire should be 3.3V. 

Red wire should be 5V.

White wire should be 9V.

When I did the measurements, the connections were measuring 2V less than what they should be. The orange wire measured 1.3V, red showed 3V, and white showed 7V.

To double check the voltages, I did a measurement along the CXA1645M RGB Encoder (pin 1 GND, pin 12 5V). What should be 5V was measuring the 3V. Checking the data sheets, the IC needs a minimum of 5V to work.

So, I ended up ordering the recap kit for the power supply (XQ155). 

While I waited for the cap kit to come in the mail, I took the power supply out of the case and took out the old capacitors on the board. As I was desoldering the caps, that distinct smell of broken caps came out. I used solder wick to remove the old solder, then used alcohol to remove all the residue from the solder wick and the expelled caps. It was pretty much a waiting game until the following week when my order came in. 

As soon as I got it, I soldered in the 9 replacement caps to the board. Again, got everything connected to test. Turned on the console.

...No pic of the screen, but it worked! The date input screen came on and there was sound as well! I had a Japanese Saturn game to test and that ran perfectly as well!

Satisfied with the results, I closed it all up and retested it. Again, all working perfectly. 

So, lesson to be learned here is to check the power going in first from the power supply. It very well may be a bad cap there that just needs to be changed. Could the caps on the board be good still? Possibly. But I'm not taking it to chance that they were good. I know that there are new ones in there, and the board is all good for another few years of play.

As it goes for the hot air part, I'm sure I had to turn the heat up on the station. There is a possible FRAM mod I could do that will save the settings and game saves without worrying about the battery much, as well as an ODE mod for it. Things I'll consider for the near, foreseeable future.