Modifying a 92631C-6 (Battery-less B-21 C-Board) to work like a 90631C-5 (Battery Backed B-21 C-Board)

[Nebula]

They are probably 0.1u, as any other decoupling cap along the other pcbs.
There is nothing silkscreened on them, just brown color.

 

[TheBurgerKing]

They are probably 0.1u, as any other decoupling cap along the other pcbs.
There is nothing silkscreened on them, just brown color.

These had some writing on them at one time. Some remnants remain. Its just worn off. I assume these are just polarized ceramic capacitors?

 

[rtw]

If you look here you can see some writing. Yes they are polarized.

https://www.arcade-projects.com/thr...battery-backed-b-21-c-board.13116/post-315026

 

[TheBurgerKing]

If you look here you can see some writing. Yes they are polarized.

https://www.arcade-projects.com/thr...battery-backed-b-21-c-board.13116/post-315026

Ahh. Thanks. Looks like it says 01 01. Since capacitors usually only have a three number designation, I take it this signifies 101?

 

[TheBurgerKing]

After doing some research, it looks like those are Tantalum Electrolytic Capacitors

 

[Paranoid_Andy]

I decided to try this myself but I wanted verify 'exactly' what I need to do so I don't mess anything up.

@rtw Does this look correct to you?

Also, I don't have any SMD resistors but as far as I know I can just use normal resistors with legs right? As long as it's 1k ohm?

Also thank you for the information!

 

[rtw]

@Paranoid_Andy I cut the tracks and soldered on to the pins 42 and 44. Yes you can use 1K normal resistors, will be a bit hard to fit though.

 

[Paranoid_Andy]

@rtw Okay I think I understand. My terminology is amateur at best so I didn't know a track was the same as a trace. So I believe you cut the track/trace that is on the PCB itself(the green part), then soldered directly to the pins on the IC.

Thank you for clarifying!

 

[Paranoid_Andy]

Works great! Thank you very much @rtw !

A side note to anyone doing this themselves. The pads on my board where the 2 resistors need to go were VERY weak and easily wanted to peel up and off the board. I had to be extremely delicate with them when adding the resistors. You may want to mention that in your post @twistedsymphony

 

[alecutheman]

Thanks for the instructions, finished modifying my C board:

I don't like cutting traces so I lifted 42 and 44 as well, and since I plan to put in in a case I'm not worried about touching it and ruining the "floating" legs. Now the hard part, waiting for the multi to arrive

 

[cruzlink2]

Just did one for @Coyo5050 .