Mega CD 2 BIOS removal advice

Hi guys

I'm about to remove and socket the BIOS on my Sega CD 2 in preparation for my region free BIOS turning up. I'm normally pretty happy about using my hot air to drop out pth dip packages (I've socketed a lot of c64s in the past).

I'm a little concerned about the number of smd components very close to the pins of the BIOS on this unit. Any advice for a successful extraction? I have hotair, a decent solder station and plenty of flux and wick at my disposal.

 

If you don't care about the original chip. Cut if out and pull the legs out after and tidy up with braid.

Else you want a proper desoldering gun/Station.

 

Was thinking that might be the answer... I'm going to have a go at wicking the pins free and try a non-destructive removal. I'll cut it out if that doesn't go well.

 

Well that was fun....

Lagged the back of the board in flux and wicked away as much solder as possible. Then lagged the nearside top of the BIOS IC and wick a load more solder away. Managed to get quite a few pins floating but a lot still soldered in.

Used hot air carefully on the back of the board, front side edge of the BIOS. Using an IC extractor to pull gently from the other side, I got the chip to let go so that I could bend it up vertically exposing the back edge pins from under the chip.

Lots more wick and flux on both sides. Managed to get most of the pins to float. Managed to release the last couple by gently rocking the chip while touching them with the iron. As soon. As they all rocked back and forward free of the holes, I pulled it.

Cleaned up the chip and the board. Installed a socket. Straightened the pins. And... we still have a working Mega CD 2.

 

nice , i didn't do it with a heat gun , only high temp soldering iron, first flux, then some new solder, then suction on each point, the problem is on each of the few mega cds i did either model 1 or 2 i ended up with stubborn point, lol, which doesn't melt at alllll. this usually ended up with a trace to repair , so your work is better I guess

 

Yeah the pins that join the ground place are a bit stubborn. I use a Metcal solder station so I just stepped up to 700 series tips to make sure I got enough heat in quickly enough to wick them out and release.

I hate doing mod/repair work when I'm starting with something that works. Always a real chance of ending up with something that doesn't!

 

totally agree with you about last part , but sometimes its beyond repair and then its real hard life , lol