Midi Phantom Power lifted from Axe Power Supply

Compuniac

Compuniac

Member
Hello,
I am modifying an FCB1010 to the controller that suits my needs but this question I guess is a generic question. Rather than using the AC 2.5mm plug it must be possible to get power from somewhere - and route it to pin 6/7.

In this case the FCB1010 uses 25mA which surely can't be a problem for whatever power supply is in the Axe.

In this case the FCB is not critical in terms of what you send to it - as you can power it before or after the rectifier with AC or DC. There is 5v voltage regulator so it can be fed with basically anything over that 9, 12, 15 whatever..

I have not yet opened my MkII (insert warranty discussion) but I am sure somebody did?

Any constructive guidance is appreciated.
 
Opening wont void your warranty, there is no seal, at this point a MKII is out of warranty anyway. I have a MK1 and my port burned out almost immediately even though I was well under the 1000ma or whatever the stated number is. I wouldn't see why not, but it would be just as easy to rig up a wall wart inside the Axe as there is a lot of empty space inside. If you can get what you need from the power supply it's worth a try, and I dont remember anyone trying this up to this point.

What I do is i have a midi cable with a little plug on it, that I just attach a wall wart to power my RJM, it takes a lot of ma's to power it. So to avoid the axe all together, i have the cable that allows me to attach directly to it.
 
dpeterson said:
Opening wont void your warranty, there is no seal, at this point a MKII is out of warranty anyway. I have a MK1 and my port burned out almost immediately even though I was well under the 1000ma or whatever the stated number is. I wouldn't see why not, but it would be just as easy to rig up a wall wart inside the Axe as there is a lot of empty space inside. If you can get what you need from the power supply it's worth a try, and I dont remember anyone trying this up to this point.

What I do is i have a midi cable with a little plug on it, that I just attach a wall wart to power my RJM, it takes a lot of ma's to power it. So to avoid the axe all together, i have the cable that allows me to attach directly to it.
Click to expand...
I agree this is nerdy - but would a sleek solution.
I thought about the walwart inside but do not wanna risk any noise.
Why this restriction on 1A for the built-in 2.5mm - is it not just connected directly to pin 6 and 7?
And btw is the 2.5mm isolated from ground?
 
Compuniac said:
I agree this is nerdy - but would a sleek solution.
I thought about the walwart inside but do not wanna risk any noise.
Why this restriction on 1A for the built-in 2.5mm - is it not just connected directly to pin 6 and 7?
And btw is the 2.5mm isolated from ground?
Click to expand...

Not sure why they limited it, or moved it from the hard wired like the older units which were hard wired, the II's all go through a circuit, and the little resistor in mine is cooked, even though I never went above. Not sure if it's isolated, but I'd bet not.

Good luck, maybe Cliff will chime in.
 
Alright - so I de-topped it - and what do I see...a 12v DC for the fan. Doesn't seem to be controlled by any temp since it is always on.
So what should prevent me from de-soldering the back of the 2.5mm plug and rig it on the fan power? i should be able to get 25mA from there.
Voila - 12 v DC to pin 6/7. (btw the inside, red wire, of the 2.5mm is connected to the right-most pin - when you look from the non-soldering side).
 
So the fan has a 3 pin connector black/ground, red +12v & white+12v.
Anybody know/can guess what the diff is on red and white?
 
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Not sure if this fits with your goals, but I modded my FCB1010 to receive both power and midi from my Axe II thru a single Ethercon cable. The FCB powers up when I switch on the Axe. Only ever one cord on the floor - it works great.

On a related note, there are no pins 6 & 7 on the FCB. The midi connectors are 5 pin. Midi pins 1 & 3 (the 2 outside ones) have no connection though, so you can use those for delivering phantom power if you want.
 
So I had a connector laying around that fits the 2.5mm input connector on the board. That got soldered to the fan it self (as there was already solder points). A bit of glue - and now the 12v DC is fed to pin 6 and 7. On the other end the FCB1010 is modified to send the 12v DC directly of the rectifier (which is then fed into a voltage regulator) - and everything is good.
No changes to anything else in the Axe and easily reversed. Don't try this at home unless you know how much current your board sux.
2017-10-06 15.55.10a.jpg 2017-10-06 15.55.10b.jpg
 
Cool, & sounds easy peasy! A sensible approach.

I don't see any mods to the FCB midi connectors in your pics. Can I assume you just added another midi jack to the FCB to deliver power?
 
cronerror said:
Cool, & sounds easy peasy! A sensible approach.

I don't see any mods to the FCB midi connectors in your pics. Can I assume you just added another midi jack to the FCB to deliver power?
Click to expand...

Here is the series of pics of what I did to the FCB so far. Next step is to figure out if I need Eureka/Uno to what I want. :)

A summary:
1. Installed a Morley spring kit on one exp pedal for 'auto return to heel' function for use w auto engage
2. Installed a 7 pin female chassis DIN plug with a lock in the FCB
3. Soldered pin 6 & 7 directly onto the DC side of the rectifier
4. Found a 2 pin female connector that matched the connector for the 2.5mm plug in the Axe
5. Soldered the new 2 pin connector to the fan (as there were exposed solder points available)
6. Disconnect the 2.5mm, connect the new 'extra' connector from the fan.

And *poof* only one cable to the board and no need for the Morley as I now have feel in the exp pedal and the sound/config in the Axe.

Best thing everything is reversible, the orginal power is available and should something happen a regular midi cable will still get you going

Not sure what would happen if the AC was connected at the same time - maybe the Axe would explode - so let's not do that. I guess I could protect it with a diode..or something.

axe2.jpg fcb4.jpg axe1.jpg fcb3.jpg fcb2.jpg fcb1.jpg
 
Nice! I like the fact that everything is reversible. I think your approach is the simplest I have seen so far to get a single cable solution. I use the EurekaProm 3.2, and like it. IMO, you can't beat the FCB w/EurekaProm for price-performance and ease of use, as long as you can accept that you will never (likely) get things like 2-way communication.

I went whole-hog on my FCB because I simultaneously got fed up with the FCB pedals, and wanted to make it smaller and lighter. My mad science project was to cut off the whole right end of the controller where the main MIDI board ends (given that you also remove the PS tranny this way - it's now a couple of lbs lighter and ~10" less wide), supply power and MIDI thru UTP, re-wire the pedal connections to the external jacks, and mod two unused 30 yr old wah pedals to be external controllers.

You have now given me the idea of modding my old Vox wah with a Morley Spring. Thanks! ;)
 
cronerror said:
Nice! I like the fact that everything is reversible. I think your approach is the simplest I have seen so far to get a single cable solution. I use the EurekaProm 3.2, and like it. IMO, you can't beat the FCB w/EurekaProm for price-performance and ease of use, as long as you can accept that you will never (likely) get things like 2-way communication.

I went whole-hog on my FCB because I simultaneously got fed up with the FCB pedals, and wanted to make it smaller and lighter. My mad science project was to cut off the whole right end of the controller where the main MIDI board ends (given that you also remove the PS tranny this way - it's now a couple of lbs lighter and ~10" less wide), supply power and MIDI thru UTP, re-wire the pedal connections to the external jacks, and mod two unused 30 yr old wah pedals to be external controllers.

You have now given me the idea of modding my old Vox wah with a Morley Spring. Thanks! ;)
Click to expand...
Thanks :)
Tell me about the 2-way comm. Doesn't work right?
This could be modified to have in/out on the same cable - easy on FCB side - on the Axe side not so much.
I guess the on reason would be to use the tuner in FCB display or what?

Haven't really gotten to the final config so I dont know if I need Eureka or Uno. I want pedal 1-5 to be scenes, 6-9 stomps and 10 tuner and I want to block the banks so I dont step on them by accident. Seems to work with standard eprom - except for the LEDs are not right.

And now I want to put a Morley Spring Kit in the second exp. but inversed so I can use it for auto engage down trem with the whammy.
 
You can do "tuner in the FCB display" with EurekaProm 3.2. There are 2 things about that, 1) it only works in one of the Fractal Audio configs (not the one I normally use), and 2), it doesn't work as well as I would like. That is not a knock on the EurekaProm as much as a limitation of the FCB display. As a result, I have learned to live without it, and just use the front panel of the Axe for tuning.

The comment about lack of 2-way communication referenced another limitation of the FCB screen - too small to show full patch names and other info sent from the Axe. Someone on the webs has modded the FCB display using arduino to show everything the MFC does, but that is way more work than I am willing to put in on a controller I paid $129.00 for.

I would ask any questions you have of Dave at Eurekasound before you pull the trigger to make sure it is right for you.
 
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