Sega — Wondermega
An absolute labour of love, or stubbornness, depending on how you look at it. This came from Japan in a sorry state: corrosion, missing components, broken traces and a RAM package with broken legs. The Mega Drive side eventually came back to life, but the Mega-CD side continues to freeze on the BIOS animation, defying everything thrown at it so far.
(1/3) New arrival from Japan! A Victor Wondermega RG-M1 aka a fancy pants Mega Drive/Sega CD combo unit that also does karaoke. Took a chance on it since it was way below normal market prices. #Sega #MegaDrive #Genesis #SegaCD #RETROGAMING
(2/3) Missing most screws and I think also a board that would have the LEDs for power and drive activity. It's a bit worse on the inside than I expected. Makes me think the chance of ending up with a restored rare console is low and the chance of a pretty paper weight is high.
(3/3) Gave it an initial cleanup. Don't know if the fading on the transistor/regulator type component is from the shmoo that sat on it, or a sign of heat damage. Might have at least 1 broken trace. At least it's looking better now and the lower part of the boards looks fine.
(1/2) The Wondermega is going in for surgery! It seems a part of the patient didn't make it. Pic 3 shows the corpse of a fallen component. At this point, it seems fair to assume the caps leaked heavily. The cancer fumes ran wild... #RETROGAMING #Sega #restoration
(2/2) Nuked the board with some isopropyl and gave it a clean. It looks a lot better than it did before (pic 3, for reference). Not sure if this will bear fruit but time will tell. For now, we rest.
What the hell is going on here? Is this a factory bodge or was someone screwing around in here? There are two sets of pins bridged together with solder on one of the sides of IC116. I was nowhere near here so I know I didn't do this. #Sega #RETROGAMING #Wondermega
(1/6) Second round of surgery for the Sega Wondermega. Removing all the caps and regulators from the main board. So that I can assess the damage. #RETROGAMING #Sega #Wondermega #MegaDrive #SegaGenesis #repair #restoration
(2/6) Trying to reclaim what water damage and electrolyte leakage tried to take away. Flooding all the through holes with solder using tacky flux, to then pull everything out and remove corrosion and electrolyte fluid. This makes way for fresh solder without contamination.
(3/6) That came out quite alright. It looks a lot better now.
(4/6) Testing the regulators to see if everything is ok. It seems like they check out fine.
(5/6) Also decided to take out the power jack to try and remove the corrosion from both it and the through holes on the board. The jack looks better but will need additional work. I'm out of Deoxit, so I need to order some to give this more TLC.
(6/6) Put the board in the ultrasonic for good measure. Since my unit is small I had to do it in halves. I think it came out looking quite alright. I checked some vias that looked suspicious for continuity and everything seemed to be good. I'm starting to get hopeful.
(1/6) Removed the regulators previously to test and also took some time to scrape away the rust with a fiber glass pen and tin the legs. Also removed all the electrolytic caps and began replacing them with new ones. #Sega #Wondermega #MegaDrive #SegaGenesis #repair #restoration
(2/6) Visual inspection post install I seem to have spotted a broken trace on the bottom side of the board. Seems almost like a via, if not then it was likely the result of an impact. Need to remove the cartridge connector to check the top side to assess what's what.
(3/6) Removed the cartridge connector and there isn't a corresponding via on the same location on the top side. Also disassembled the cartridge detection button. It's heavily corroded and isn't buzzing on the meter when depressed. More fiberglass pen scrapping ensues.
(4/6) Looking much better after scrapping. Never been so happy to find a remnant of Deoxit. This helped a lot as too. After reassembling the button and letting it react for a bit. The multimeter showed that the button was functional again. Cartridge slot holes cleaned, top side.
(5/6) Drag-soldered the connector back on, looks good. Also patched the broken trace with a piece of kynar after stripping the isolation.
(6/6) Desoldered the power and reset buttons. No surprises, corroded. More scrapping and scrubbing and squeezing of every last drop of Deoxit. The reset button was already broken on arrival. Contacts turned out alright, reassembled and tested the console. Sadly, for now, no joy.
I have since removed the wire to patch that trace, it seems like that was intentionally cut in production. I've seen the same trace cut in pictures of other boards.
Last night I felt like soldering so, even though I haven't gotten the console to work yet, I went ahead and partially recapped the AV board. I didn't change out the tiny caps because I lack those values in that size ATM. Also reflowed all joints. #RETROGAMING #Sega #Wondermega
Not ready to die yet, huh? Since it looked ok-ish when the cartridge detection switch wasn't closed, I figured I'd check what it would look like if it wasn't missing the cable that connects both halves. Seems like it freezes on startup. #RETROGAMING #Sega #Wondermega
Wondermega went in for a third round of surgery. a long shot and I didn't think this would solve the freezing issue on the CD side but it couldn't harm it either. Some sludge can be seen and several caps did smell when removing. #RETROGAMING #Sega #Wondermega #repair #restoration
Alas, the end result, as suspected was the same. Still freezes on what is likely the first frame of animation. 😔
However... What is this I spy with my little eye? The mega drive side has become functional! I don't think this had anything to do with today's recap. Probably tied to the Deoxit applied to the cartridge connector recently. #RETROGAMING #MegaDrive #Wondermega #restoration #repair
Final Wondermega work item of the day. Replacing the capacitors on the AV board that I had yet to replace (the ones not marked in the first picture).
The Mega ED Pro doesn't work on the Wondermega, at least on latest firmware (v4.20). It works fine on my other mega drives (seen on Nomad pic). On Wondermega it keeps asking to update IO core and rebooting. Is this a known issue @krikzz? Anybody experience the same? #RETROGAMING
Interesting, if I disconnect these two cables, I can hear the motor and there is movement in the optical drive assembly. Additionally, if it's open it closes automatically (also seems to pop up a bit after closing or even when I boot with the lid closed. #RETROGAMING #Wondermega
Got myself a new toy, a flash kit programmer for the Mega Drive. Since the Mega Everdrive Pro isn't working on my Wondermega, this is a way for me to run the 240p test suite. The edge is beveled and it's pretty straightforward to use. Let's run some tests! 🧵👇 #Wondemega #Sega
Everything is ok on the first two tests in the menu so the BIOS and the HINT register check out but the following posts won't be as positive.
Flag and Command registers failing.
More Command registers failures.
Final Command register failure and Program RAM failing on bank switching.
More Program RAM failed tests and also failing WORD RAM tests.
More Prog and Word RAM failures.
And the last of the failed test screens. Seems like pretty much most of the suite of tests is failing. 🤪
Had some parts arrive from UTSource. I just quickly ran the transistors and regulators through the tester to see if they all checked out alright and they do.
Wondermega day again. I was measuring voltages on the MCE, the BTL driver, the DC-DC converter, to try and find something that looked out of whack to my untrained eye. I wasn't getting anywhere and then I see this... It seems like someone savaged one of the RAM packages. #Sega
Clean pull. It turned out to be 3 broken legs.
And another clean pull from a broken MCD1 donor. Installed the RAM package aaaaaaannnddddd... The same BS... This was very anticlimactic and disappointing. Still freezes on the BIOS screen, fails the exact same tests on the 240p test suite.
Candy day! I love the candy that Console5 packs in their orders. Even though my Wondermega isn't fully functional, I decided to treat it to a new drive belt. #Sega #Wondermega
Replaced all the regulators too for good measure. They all tested fine, eventually only one of them would warrant replacing, the lettering was faded on it, maybe a sign of overheating.
Replaced the BTL driver.
And finally, replaced a transistor and the DC-DC converter on the AV board. The end result is... The console is exactly like it was before. MD side working but with no sound and Mega CD side freezes on the BIOS animation. Some day... 🙂
Oh, I also desoldered the other RAM package to check if it had any broken legs, like the other one did but alas, it didn't.
