Franklin FKB-3 Project

User avatar
Polecat

02 Jun 2019, 00:47

I just finished a fun little project, installing new guts in a Franklin FKB-3. I bought one of these last year expecting it to have green Alps. That was before Chyros posted his review of this model, which identified the switches as Datacomp foam and foil. I couldn't get it to work on any of my converters, and being foam-and-foil I didn't put any effort into fixing it electronically. Since I liked its looks, and its black and gray MX-mount double shot caps, I decided to replace the PCB and plate with something more "mechanical". I found a brand new Chicony KB-5160AT with Futaba MA switches (MX mount) to use as a donor, and nobody seemed to object to its sacrifice, so I tore into things. As it turned out everything I did to the Chicony internals ended up being completely reversible. I know Futabas aren't everyone's thing, but this is going to be used mostly for entering data, and its extreme tactility agrees pretty well with my two finger typing, so I'm very happy with it. The Franklin case makes the Futabas sound *very* pingy, and I'm typing on it right now with a big stupid grin on my face.

The swap was fairly painless. The LEDs on the Chicony did not line up, so I moved a few components to the bottom side of the PC board and threw together a little LED board which sits on top of the main board. I added a power LED, and used some modern G-Y-B-V LEDs to give it a bit of color. The cutouts for the F-keys and numpad didn't quite line up, so I had to shave a tiny bit off the outer edges of the openings. All the Franklin caps fit except the spacebar, so I bought a 9.75u from SP in dark gray for that. The upper stabilizer on the Enter key did not line up, so I reversed the insert and bent the wire a bit. A black Datacomp cable turned out to have the same connector and pinout as the Chicony (!), so that was easy. I think that's it, here are a few photos.
Attachments
Regutted Franklin FKB-3
Regutted Franklin FKB-3
DSCN0447.JPG (812.73 KiB) Viewed 1585 times
Chicony PC board and plate
Chicony PC board and plate
DSCN0442.JPG (817.34 KiB) Viewed 1585 times
Futaba MA switches and Franklin DS caps
Futaba MA switches and Franklin DS caps
DSCN0439.JPG (815.74 KiB) Viewed 1585 times
LED board
LED board
DSCN0441.JPG (804.64 KiB) Viewed 1585 times
Modern LEDs and crummy camera red shift
Modern LEDs and crummy camera red shift
DSCN0453.JPG (797.41 KiB) Viewed 1585 times

User avatar
Chyros

02 Jun 2019, 01:18

interesting! It's good to see you made such nice use of the board; it's definitely a looker after all, just with rather meh switches. Futaba MA aren't great IMO, but definitely have perks of their own - they're certainly not without merit. Noice! :)

User avatar
whiffysole

23 Jun 2019, 22:12

I love Futaba MA switches, can we get a sound demo?

User avatar
Polecat

24 Jun 2019, 00:28

whiffysole wrote:
23 Jun 2019, 22:12
I love Futaba MA switches, can we get a sound demo?
Send a typist with a video camera, I'll provide the Futabas. I like them too. Infinitely more than the foam and foil mushmat that was in there before. Sorry, I have no way to record a video. My phone still has a rotary dial, and my $2.99 camera barely has a camera inside.

Post Reply

Return to “Keyboards”