FCB1010 mods: "phantom power", remove built-in expression pedals, change EPROM

  • Hi, I made some mods to my FCB1010 foot controller, here is a verbose walkthrough for those interested. Note that it requires some fiddling with mains-current which can become dangerous if you do it incorrectly, so only do this if you are sure that you can do it well (some jurisdictions might require you to have a license to work with mains-current).

    This is the end result:
    <pics 1,2 of box>
    [Blocked Image: https://i.imgur.com/TQa49tv.jpg][Blocked Image: https://imgur.com/yv8XwUv.jpg]This box sits behind the KPA. It has midi in and out for KPA, a power input jack, and provides power and midi to the floorboard via a network cable (RJ45 / Cat5, like the Kemper Remote uses).
    <pics 3,4 of floorboard>
    [Blocked Image: https://imgur.com/I5uWV8q.jpg]

    [Blocked Image: https://imgur.com/Krp4iNM.jpg]The floorboard is much more compact than the bulky original. No mains power at the feet feels safer. Only one cable means that I can quite easily push the unit around on the floor with my feet. I use EurekaPROM 3.0 which has all the normal stuff and also lets me use the Kemper looper (unsupported by Kemper and I can't get undo/halfspeed/reverse to work but jamming with myself is fun and a good tool for composing). I think the midi looper functions used to work in an older firmware, I believe it stopped working around when new delays or morphing was introduced. I have only tried it with the latest beta

    You might want to buy all needed parts and tools first, so that you don't have to wait for delivery and be without your floor controller for too long. I bought almost everything online, from aliexpress or thomann.

    Parts used:

    Tools needed:

    • metal saw
    • metal drill https://www.aliexpress.com/ite…Drilling/32759082236.html (I have 4-32 mm)
    • drilling machine
    • normal drill bits for the plastic box
    • soldering station (or soldering iron but when I used an iron it was very difficult)

    • screwdriver, I think a standard "phillips head" (shaped like a +) is enough for the FCB parts. if you mount the jacks with screws you will also need a smaller screwdriver (such as these which I have https://www.aliexpress.com/ite…e-Laptop/32489598823.html).
    • multimeter/Ohmmeter (only for checking which wire inside the midi cable goes to which connector: you could do it with a battery and a LED or similar if you don't want to buy a meter)
    • wire cutter and wire stripper

    First remove the bottom plate by unscrewing all screws on the underside.

    <pic 5 of eprom>
    [Blocked Image: https://imgur.com/Nn2qmKJ.jpg]
    Changing the EPROM is very easy. The direction is important - check that the little half-circle-shaped dent in the black plastic is in the same direction as the EPROM that you remove. First loosen any glue which holds the old EPROM in place. Then lift it up carefully with a flat head screwdriver. Before pushing the new EPROM in place you might have to bend the metal connectors (legs) so that they fit.

    <pic 6 before cutting>
    [Blocked Image: https://imgur.com/juPkNNg.jpg]
    On to the other mod. Remove the power transformer and the power jack by removing additional screws. Also remove the power button. Cut the cables needed to get the parts loose. Pull off the cables from the light sensors that measure the expression pedal position. I didn't cut them off but just taped them to the chassis so they don't bounce around too much inside the FCB. (Later on I plan to connect them to new TRS-jacks so that I can connect external expression pedals and have the FCB treat them like the internal ones. The FCB expression pedal calibration will hopefully be able to tune to the potentiometers in my expression pedals. Others have done it so it should be possible with at least some expression pedals.)

    Remove the black plastic end of the floorboard by unscrewing screws.

    Now the expression pedal-side of the floorboard is exposed - cut it off, and also cut off the bottom plate. I used a metal hand saw, which took a while, but it worked. (I just measured the left-over part of the bottom plate, it's 19.6 cm.)

    See if the plastic end fits on your newly sawed edge. You might need to do a small extra cut so that the parts fit, I don't remember exactly (probably not, but in any case it's not difficult). Glue it back. (This isn't as stable as using screws like in the original design, but for me it's stable enough.)

    Drill a hole for the RJ45-connector in the backside of the metal chassis. If you plan on mounting it with screws: drill small holes for the screws as well. In the order you prefer: mount the connector and solder the appropriate cables onto it.

    The important part of the wiring is that the second and fourth midi pins are connected in the same way on both sides of the RJ45-cable. You can look at photos of my notes for the wiring if that helps.
    <pic 7 wiring fcb>
    [Blocked Image: https://imgur.com/sIMg3YM.jpg]

    Remember to apply heat shrink tubing before soldering. You will solder the two yellow 10V AC-cables (which you cut off from the transformer) directly to the appropriate position of the jack. You will also solder 4 midi wires to the jack, then the other ends to the midi connectors on the inside of the FCB (this allows you to keep using the old midi jacks of the FCB, though you need to get power through the RJ45 anyway). Shrink it over the finished solder joints using heat from the soldering iron. Tape the wires to the chassis so they don't bounce around (this could loosen your soldered joints). For mounting the RJ45-connector, I used both screws and glue.

    If I remember correctly the floorboard should now be finished. On to the box.

    Cut the midi cable in half.

    Drill holes in the plastic box for the following things:
    power jack (and mounting screw holes) (I drilled some holes and then carved with a knife)
    2 midi cables (small holes for just the cut off cable ends)
    RJ45 jack (and mounting screw holes)

    Check that all parts fit. Mount them either now or after soldering. I used screws and glue for the connectors, only glue for the transformer (I had to bend one of the legs first so it fit). The midi cables required neither: make a knot on the inside (I'm not sure if also adding glue makes it better or worse).

    <pics 8,9,10 of box wiring and box>
    [Blocked Image: https://imgur.com/GQoOXa6.jpg]

    [Blocked Image: https://imgur.com/Di4SMBW.jpg][Blocked Image: https://imgur.com/tNEwW5d.jpg]Solder all connections, look at the attached picture if that helps you. Power jack to transformer, transformer to RJ45-jack (only the thinner wires that previously went to the midi board, yellow in my case), wires inside midi cable to RJ-45 jack (check which wires correspond to which connector pins with the multimeter). Remember to add heat shrink tubing before soldering. Shrink it over the finished solder joints using heat from the soldering iron. Isolate the mains-current connections carefully with electrical tape. Note that it will be very dangerous if you fail to do these parts safely, in some jurisdictions you may need to be an electrician to work on mains-current. Don't proceed if you are not sure that you can do it correctly.

    Close the box and the floorboard, connect everything, see if it works! Hope this is useful or entertaining for someone! :)

  • I've been wanting to minimize mine like this but don't have the skill or patience to do something like this. Would you ever do this at a charge?

    Is it because light travels faster than sound that you appear to bright until you strum a chord?

  • Cool mod, man. Thanks for the pics! Question about the transformer: You have a picture that shows a 9V .3A transformer. Is that the original? If not, how is it working? I'm concerned about the max current draw.

    I'm about to mod mine to cut out the transformer and put in a DC input powered from my pedal board's power supply, but the max power output from my p/s is about 4 Amps (9V, 450mA).

  • why not just get a MeloAudio MIDI commander. Its only $150, smaller than FCB1010, and already built to work with kemper.

    Smaller, yes, but that means fewer buttons. Looks like you can only control 2 stomp boxes while in Kemper mode using performances. Might not be a huge deal, but I like to turn stomps off and on instead of switching performances (most of the time). UNO4, single cat5 mod and pedals cut off, works for now until I decide if I really need the Kemper remote.