<3<3MMPSU Rev E Power Supply for Memorymoog

<3<3MMPSU Rev E Power Supply for Memorymoog

Our <3<3MMPSU is a modern replacement for vintage Memorymoog and Memorymoog Plus synthesizer power supplies. This modern switch-mode design provides cleaner power and allows you to remove the noisy fan, heatsink, and giant power transformer, giving you a more efficient, quieter, cooler, and lighter weight option for your classic synthesizer. Better yet, NO DRILLING to install. The large base plate, which doubles as a heatsink, adds rigidity, better AC isolation, and comes pre-tapped for easy installation. Our back panel (optional add-on for $25) allows you to remove the bulky heatsink from the back of the synth for a narrower profile. Mounting hardware included.

Not sure how to install voices in your synth? We're currently offering an optional installation service with orders of sets of 6. All you have to do is ship us your synth's module board. We'll do the installation and ship it back to you.

The battery back-up circuit protects your patch memory in case of peripheral component failure.

Use our instructions to install the <3<3MMPSU, or share them with your synth technician.
Would you like us to install your voice chips?
Include the Back Panel with your order?
$ 700.00 USD
Price:
$ 700.00 USD
Quantity:

About the warranty

Lifetime warranty: In the highly unlikely event you need a replacement voice chip down the line, we'll send you one for free. Just send us the untampered faulty module and we'll send you a replacement.

(<3<3 is not responsible for shipping cost of returned items)

Comes with a two-year warranty.

About the battery backup circuit

The battery backup circuit is designed to protect your patch memory in case of peripheral component failure. When a component that runs on the 5-volt rail fails in your synthesizer, it can cause the 5 volts to sag. This sag can make the CPU malfunction and scramble the patch memory as a result. This circuit senses the 5-volt rail that powers all the digital circuitry and switches it to battery power, should the 5-volt rail dip below a safe threshold. Share the instructions with your synth tech.

We strongly recommend having an experienced technician install the <3<3MMPSU

Installation services at Switched On

Looking for a qualified technician to install the <3<3MMPSU? Contact our partners at Switched On at +1 (512) 565-0663 or switchedonaustin@gmail.com.

Physical details

  • Fully tested with an 8-hour burn-in period
  • Fully encapsulated for optimal thermal coupling, static protection, and more rugged durability
  • Socketed and easy to swap out
  • Low tolerance matched transistor pair for exponential converter
  • Low tolerance voltage reference
  • Short circuit protection

How to remove and ship your synthesizer module board

You'll need: screwdriver, sharpie, plastic bags for loose screws
Step 1
Make sure your synth is turned off and the power cable is unplugged.

Remove the four screws on the left and right side to loosen the face/lid of your JUNO-106. This gives you access to the inside of your synth.

Place the screws in a plastic bag for reinstallation.
Step 2
Lift the synth's lid and locate the module board. If you're looking directly down into your synth, the module board is located above the keyboard on the left side.
Step 3
There are five wire harness connectors on the module board. First, use the sharpie to label each connector's positions for reinstallation. Then, unplug the connectors.

Pro tip: Don't let your module board flex while you unplug the connectors. Let a friend help or use one hand to unplug and the other to hold the board still.
Step 4
There are six small screws connecting the board to the body of the JUNO-106. Carefully unscrew each one.

Place the screws in a plastic bag for reinstallation.
Step 5
Remove the board from your synth.

Then, carefully package it for shipping.
You're ready to ship us your board for module installation. Ship your board to Double Heart Audio LLC 2103 E 18th St, Unit B, Austin, TX 78702.

Disclaimer: Double Heart Audio is not responsible for lost mail or damage that may occur through a mail carrier's transport of your board. We recommend that you email us a tracking code along with your order number when your board is en route for extra reassurance. We'll contact you upon receiving your board. Once we complete the installation, we'll get in touch again to let you know when we've shipped your board back to you. You'll pay for our return shipping cost at checkout. Estimated turn-around time is 2 weeks.

How to install the <3<3MMPSU Rev E Power Supply

You'll need: Soldering iron, solder, wire cutters, wire strippers, DeoxIT brand (DN5) deoxidizer, rubber gloves, phillips-head screwdriver, 5/16" and 11/32" socket wrenches, a standard household degreaser, rags, plastic bags for loose screws
Caution
This equipment should be installed, adjusted, and serviced by qualified electrical maintenance personnel familiar with the construction and operation of the equipment, and the hazards involved. Failure to observe this precaution could result in bodily injury. 

How to remove the original linear power supply:

Step 1
Important: Back-up your patches before you start.

Installing the battery backup circuit will temporarily disconnect the battery power from the static CMOS RAM, and will erase all patches.
Once you've backed up the patches, make sure your Memorymoog is unplugged from the AC outlet.
Now, remove the 9 wood screws on the front and each side of the unit, and the 3 sheet metal screws on the back of the unit.
Step 2
Apply a liberal amount of DeoxIT to the four screws mounting the power transformer to the chassis and let soak.
Step 3
Unplug the two wire harnesses connected to the left side of the power switch.

Important: Do not remove the green/yellow stripe Ground wire coming from the IEC power inlet!
Before
After
Step 4
Unplug the four wire harnesses and remove the three screws that attach the original power supply pcb to the large black heatsink at the back of the synth.

There is a white heatsink compound that permanently stains clothing! We recommend wearing rubber gloves when removing!
Before
After
Step 5
(Optional step)

Remove the 6 screws that fasten the large black heatsink to the back of the synth. Clean the residual white heatsink compound with a rag and standard household cleaner/degreaser.

Replace the large heatsink with the <3<3 back panel using your 11/32" socket wrench and the hardware provided.
Step 6
Unplug the fuse wire-harness connector and remove the screw that fastens the fuse housing to the bottom of the synth.
Step 7
Remove the four screws that mount the fan to the chassis.
Step 8
Remove the four screws that fasten the power transformer to the chassis. It will take some effort to remove these, but they should come loose after being sufficiently soaked in DeoxIT.

Reapply and let it soak if needed.

The power transformer and fan should now be free from the chassis.

Now you're ready to install the <3<3MMPSU:

Step 9
Using the 4 screws provided, fasten the <3<3MMPSU to the chassis with the 15-pin connector facing towards the front of the synth.

The screw holes in the <3<3MMPSU base plate align with the original screw holes used to mount the power transformer.
Step 10
Attach the green/yellow stripe ground wire to the grounding screw using a 5/16" socket wrench and the 6-32 lock nut provided.
Step 11
Attach the blue and brown wires to the power switch with the blue wire attached to the top terminal and the brown wire attached to the lower terminal.

Important: Make sure the connectors are properly fastened to the power switch terminals by checking that they aren’t just being held in place by the plastic insulation on the connectors!
Step 12
Plug in the 15-pin wire harness connector with the yellow wires towards the left.

Then, plug in the 3-pin red and blue wire harness as shown in the photo.

Proceed to battery backup installation (Step 13).

Battery backup circuit installation:

Caution
Never unplug the little 3-pin connector on the new PSU board while the synthesizer is powered on.
Step 13
Remove U14 from its socket and bend pin 10 upwards.

Reseat U14 in its socket and (important) make sure that pin 10 has no connection anymore!
Step 14
Cut emitter of Q1 near PCB (the lead closest to the back of the synth) and bend the pin upwards.
Step 15
Solder a jumper wire between the via near U2 and the via near U13 (pin 14).

(See photo in Step 16 for overhead view of jumper wire solder-point.)
Step 16
Important: Make sure to leave enough length to this wire to allow you to access the DMUX board (below) while the 3pin wire harness is still plugged in.

Solder red wire coming from JP2 connector on the new PSU board to R14 side connected to U1 pin 26.

Important: Sometimes an additional resistor is soldered in parallel to R14. Remove that!

U1 pin 26, U10 pin 17, U22 pin 1, pin 4, pin 10, and pin 13
should now be connected to the red wire.
Step 17
Remove CR5.
Step 18
Important: Make sure to leave enough length to this wire to allow you to access the DMUX board (below) while the 3pin wire harness is still plugged in.

Solder blue wire coming from the JP2 connector on the new PSU to CR6 cathode (grey ring).

Be careful not to touch any neighboring traces.
Step 19*
*When applicable to your Memorymoog

Some Memorymoogs have a trace cut and a jumper added on the bottom of the digital board, underneath U24, circled in blue in both pictures.

To check for this mod, you'll need to remove 4 screws (see red arrows) and tilt the digital board and common analog board backwards on the rear hinged standoffs to see the bottom of the digital board.
If you notice this mod, simply re-solder the wire to reconnect it's original trace, as shown in picture 2.

If you don't see a mod you can disregard this step.
Step 20
Calibrate the power supply as described in the service manual. Reload the backed-up patches.
Reset and battery back-up are now synchronized.

Here’s what will happen if the +5D rail goes under 4.55V: A reset will occur, stopping the computer. The CMOS RAM will be supplied by the battery, the read/write lines will be disabled, and the computer won’t corrupt the CMOS RAM.

Don't hesitate to email us if you have questions. <3<3

Happy soldering

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