PPG Wave 2.2

This is a restoration of a PPG Wave 2.2 done for a client. The PPG was very dirty and dusty on the inside and scratchy on the outside. To my big surprise there was no backup battery inside it, it had been removed and replaced by backup caps. This PPG was completely restored both electronically and cosmetically. The display light had gone black a long time ago so I took the challenge of creating a new light for its LCD.

Here it is, in the state I got it in. You might not see it in this image but it is actually very scratchy on the surface of the black parts of the PPG.

In this image you can see the scratches more clearly, notice the ones at the back of the unit. and the old price tag and some stains. This will be fun ; )

Scratches on the top of the sides.

Dust on the back of the PPG. Notice the scratches on the top side.

More of the same.

No lights here. The lights where all black when I looked at them.

Very unclean. Well that is about to change ; )

Black lights anyone ? These got their power directly from the big electrolytic cap shown further down this page. the Volts measured was plus minus 4,95Volts, not far away from what ordinary LEDs need (3.0 ~ 3.2 Volts). I created a experimental PCB with some resistors and blue LEDs which I glued in place using two screws (The heads of the screws was glued onto the front panel backside where the old lights used to be, and the new PCB fastened onto those screws with nuts). 

This PPG can not have been cleaned for a long time. Notice the separate outputs and midiboard at the back of this unit.

The big cap I was talking about earlier, 10 000 uF 16Volts. To be replaced with a fresh one in a second.

Some more of those dirty keys I am so used to these days.

The orientation of the Keyboard cable.

The color of the Keysprings. Red = White keys, Blue = Black keys. Important to remember since the springs are of different lenght. Which might not be seen in these images, but it is seen when they are removed from the keybed.

The white and black keys removed.

The Key bed frame and the old bushings still in place where they have not dried out and come loose when the keys were removed.

Old bushings removed, notice how dirty everything is.

Dried up and all used. Good for nothing more than throwing away in the garbage.

New fresh bushings in place, and the key bed frame has been cleaned. The wider Y up and the narrow Y down. That´s the rule when inserting new bushings. You also might want to clean of the lubricant now or you´ll notice how the keys want to get stuck. This effect disappears after a few days, but if you want to get playing at once after an operation like this it is better to clean and dry them up a bit with a soft piece of cloth.

The I/O Card, Processor card and the two voice cards seen from the front of the unit. Notice the Backup caps installed here instead of an internal battery.

Same set of cards seen from the back side of the unit. The Eproms seen here are V6.0, soon to be upgraded to V8.3.

Documenting all the wire orientations, so that I can go back and have a look on what wire goes where and how.

All the cards removed for re-caping.

The Midi board and separate outs, which I am thinking of cloning some day.

The Old tantalum caps on the voice card.

New tantalum caps on the voice card. Leads on these PCBs are extremely fragile, be sure not to heat too much for too long or the lead might follow the component on its way off.

Could not find the same value axial caps, so I had to go with radial ones instead.

Old electrolytic cap.

New electrolytic cap in place.

Here a old cap on the front panel PCB board.

Old Tantalum cap on the front panel PCB board.

A new cap for the front panel PCB.

And a new tantalum for the same board.

Two new caps for the motherboard. It is quite surprising how little electronics there is in the PPG. I imagined layers upon layers of boards. Most of the PPG is made up of a lot of air.

Ok, as choking this might be. But it is true, I just had to try out my ability to bring back the old shine to this instrument doing a paintjob. Shown here is only the front panel, later I did the rest of the PPG as well and it got really nice in the end.

The back logotype of the PPG was masked and cut out using a razor blade. I feared the worst, but .....

It actually looked nice after the paintjob.

Looking nice isn´t it ? The new paintjob is done, and no more scratches can be seen.

Ok, so the next thing was the light problem. Here I am testing the blue LED solution. I decided to use a plastic 2mm thick piece of plastic to spread the light across the display, actually three LEDs was too little. I also added another piece of reflective material in order to bounce back the light towards the LEDs again.

Sorry for the blurry image but I do not have a stand for my camera and night shooting requires a slower shutter time, so holding it absolutely still by hand is an impossibility. anyways, this is what it would look like in the dark (Still just trying it out).

Another picture of the lighting, a little better one as well ; )

Seeing the light from another angle. From here you can see how the light is bounced back with the help of some reflective material.

Here I added some more LEDs to my construction, unfortunately one of the LEDs was broken resulting in an uneven glow. Later I replaced the broken one and also added smaller LEDs in between the large ones. Damn it is hard to stand still in the dark ;)

This is the last image, I placed back the black knobs and delivered the PPG to one happy owner. I feel like the guys in "pimp my ride" .. Only this is "Pimp my synthesizer" .... To bad not to many girls are playing synths ... Grrrrr ; )

Many small improvements were done to this PPG, the keyboard was raised back to the same level as the bender assembly making it look nice and professional. The benders got new material inserted for the wheel stoppers to give a luxurious new feeling when bending the wheels. The wheels themselves where cleaned from years of fat fingers. The Keys were all cleaned with soap and treated with a Plastic polish chemical for a shiny result, as were the knobs. The multi connectors for the cards were cleaned from years of oxide. The entire synth was cleaned on the inside. Many of these small details never got photographed. I am simply too interested in the work on the synthesizers rather than taking images every second. So far this restoration has cost the client somewhere in the region of $220 USD, not including the upcoming upgrade to V8,3.