1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Help with power modding a vintage Pedal

Discussion in 'Pickups & Electronics [BG]' started by tlite, Oct 29, 2020.

  1. tlite

    tlite Supporting Member

    Aug 18, 2016
    I just bought a vintage Ibanez FL-305 Flanger:

    It is designed to take two 9V batteries- no power cable jacks.


    I have modded a standard single 9V pedal to take a power supply but not sure about the right way to mod this one.

    I plan to use two battery snaps (wired from power supply in reverse polarity) to snap into the pedal's 9V snaps.

    The question is whether I can connect the two power wires and the two ground wires of the 2 new battery snaps to terminals on a single DC jack, running off of one 9V cable from the power supply,


    Do I need to separately wire each snap to its own DC jack with its own independent 9V cable from the power supply?

    LoveThatBass likes this.
  2. ex-tension


    Jun 11, 2009
    If this schematic is correct: Ibanez - FL-305 Flanger the batteries are connected in series so, the unit needs 18V.

    This you can't do:

    This may work depending on your power supply:
    If your power supply outputs are true isolated it will work.
    A better solution is powering the pedal with 18V supply.
    tlite likes this.
  3. tlite

    tlite Supporting Member

    Aug 18, 2016
    Thanks! I tested it up with both setups and neither was working, but it does work with two separate batteries, or a 9V power supply and a battery. I think you nailed it as my PS is an el cheapo and not fully isolated. Any guidance on how to wire it up for the 18V supply?

    That is super helpful- I should've googled the schematic myself (but I'm still reading schematics at a 3rd grade level so really appreciate it.)

    I had been wanting to do this without severing any original wires, but I'm guessing to do this I'd cut off the pedal's two original snaps- then twist both positive wires from the pedal's battery snaps together, do the same for the two ground wires, and then use a single DC jack connected to an 18V cable?
  4. tlite

    tlite Supporting Member

    Aug 18, 2016
    Actually, i think I got it maybe?

    Plug in two 9v batteries and measure voltage from the negative of one battery to the positive of the other.

    When I get a +18v reading I'll have identified the two leads I'll be using and will leave the others disconnected?

    Connect a single new snap to a DC jack and connect the positive and negative leads to the ones I identified with the multimeter in the pedal.

    Connect 18v cable to the jack and should be good?

    Ought I to wire in a diode for protection here as well?

    Or do I have all this completely wrong...?
  5. Yes, the 9 volt batteries are connected in parallel for more current handling not voltage increase. Tie the two reds together and then the two blacks together. Now you need to know the voltage polarity of the power supply ( is it + center and - on outside sleeve or is it -center and + outside sleeve) then wire the jack accordingly. Red wires are + and black wires -
  6. tlite

    tlite Supporting Member

    Aug 18, 2016
    Thanks! It looks like @ex-tension has it right, I think? The schematic shows the batteries in series, and I measured voltage with two 9V batteries plugged in across the negative pole of one battery and the positive of the other and am showing 18V.

    So, I'd either need a single 18V source (still not quite sure how to wire it up, per my 2nd post), or set it up for two isolated 9V cables. (I get what I'm supposed to do, but should anyone feel particularly professorial in edumacating me as to why I need isolated supplies to make this work, I'm looking to learn...)

    Thanks again!
  7. tlite

    tlite Supporting Member

    Aug 18, 2016
    Thinking this will work. Awesomely illustrated all by myself. "1" and "2" are the Ibanez battery snaps.


    I also think wiring a diode for circuit protection might be good practice. Shunt and Series make sense, or just one? None?

    I have a bunch of 1n4148's- those OK for this purpose?

    Thanks again, folks.

    Will try when I get home and report back.
    ex-tension likes this.
  8. ex-tension


    Jun 11, 2009
    Yes, that will work. Congratz for figuring it out yourself.
    Just 'series diode protection' is enough and 1N4148 is OK.
    tlite and Crater like this.
  9. tlite

    tlite Supporting Member

    Aug 18, 2016
    Thanks for all the help.

    It works!
    ex-tension likes this.
  10. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

    Mar 4, 2021

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.