Changing broken G key in maxikorg

I brought back my maxikorg from Randolf while he is away on tour.

I managed to change the broken G key using moog prodigy keys bought from Costa Rica via ebay.

They fit like glove. You will patience and much care to slowly shave and file the J hook to size to fit into the maxikorg slots.

Otherwise the size is identical to maxikorg orginal keys.

Here is the maxikorg with the Moog keys and closeup of the original broken key (glued using an ice-cream stick)...This Maxikorg is really a bad buy...for USD 2000, its really trashy.

OEM Korg IC chips? Possible? Yes for MiniKorgs, NO for Maxikorgs 

The facebook page korg maxikorg DV800 has a link to buy OEM reversed engineered chips at very  reasonable prices from EU. These chips were reversed engineered based on the original ones. Looks like I may have to order them soon for this maxikorg

After note: The seller of the chip is a nice chap by the name of Toni 

http://www.wutierson.com/en/home/parts

His blog is http://www.matrixsynth.com/2013/03/the-string-machine-project.html.

He has advised that he has to date only developed chips for Minikorgs 700/700s and traveller chips for Mini and MaxiKorgs.

His chip for Oscillator for DV800 Maxikorg is pending testing because he has no MaxiKorg to test out and will only be out in 2015/2016...

I have also taken the chance to take photos of the original korg chips VCO and traveller chips

Brief maintenance of Minikorg 700s

TheI ordered a brand of synthesizer fader/ potentiometer grease.

It was kinda of waste of money. It didn't seem to make the sound better but it seems worse off...softer and weaker portemolo.

Here are the innards of my minikorg 700s.

This is a picture of the offending/vibrating oscillator panel...nope the grease didn't make it better...I was recommended to use electrical spray to clean it up...no sir, I am not going I risk it...not on my only korg left (DV800 is almost gone to Synth heaven)

The birth certificate of the 700s 

It could a case of leaking chemical spray or water? The seal and date of manufacturer and testing are all blurred out...so there is no way I determine the manufacturer late.

Everything falls to bits

DV800 Kaput!!

14 sept 2014..it is a bad evening.

I was playing the maxikorg to Kitaro's 'Koi', everything came to bits at the chrous.

The drifty pitched upper deck VCO gave way and stopped sounding. My worse fears came true...it stopped responding only to the keys and became a 1 note drone. I have spent so much time and money to only to finally come to terms I have secured a very bad deal..

I paid so much for a faulty maxikorg...

It's really bad, all is coming to bits.

Cosmetically restored Maxikorg DV800

Here are the photos of the cosmetically restored DV800.

Paint job by my dear father, I did a relatively less than ideal patch job that resulted in less than ideal finishing for the side panels.

Depending on my remaining budget, I may get a carpenter to refabricate a new set of side panels.

That's all for now, I will update again after checking the synth with the technician next week.

Tuning the Maxi Korg Dv800

I unscrewed the top panel of the DV800 to access the tuning pots. I am a newbie and so I did some calculated risk and by trial and error as info my friends from vintage synth forum...

Warning- I do not accept any responsibilities for any mishap or loss of lives and equipment, I am not a professional, I am just documenting my findings here.

Take all precautionary measures while tuning. 

I used a test pen to do my adjustment and wore rubber slippers while tuning.

I located the VCO circuit board located on the left (upper deck sounds). The right controls I tested were for the right (lower deck sounds).

Use the test pen and I tuned the 2nd, 3rd and 4th pot. I tuned taking reference from the c key of my minikorg and also with an tuning app for my ukelele on myiPhone.  

Tuning the MaxiKorg

Tuning Pots Adjustment for Maxi Korg DV800

Warning: I do not accept any responsibilities over any damage to any of your equipment or loss of lives/ injury should you service your synth using my steps. 

I am just documenting what I have done, it does not represent any professional standpoint or advice.

Please take all precautions while servicing your synth, especially when it comes to live electricity.

Precautionary measures

I make sure I do not touch any electronics with my bare hands. All tuning is done using a test-pen and I made sure I wore rubber slippers while servicing the synth with live current.

Steps

I took apart the top panel of the DV800 and located the pots for VCO on the top left hand corner. I am a newbie so by trial and error and advise from friends from the vintage synth forums, I  adjusted the 2nd, 3rd and 4th pots on the left VCO circuit panel. I tested and noticed that the right VCO panel, which is identical is for the lower deck.

I tuned the pots and played the notes against my MiniKorg to tune, I also tested the tuning against my Ukelele tuning app on my Iphone.

The previous owner has marked with a sharpie pen the position of the pots. I tuned it all the way to the extreme end just to get the synth in tune.

I noticed that this helps to alleviate my out-of tune upper VCO deck, but does not solve the problem 100%, it still takes time to warm up to get in tune and some extreme low notes (low G and C) are still out of tune by a cent.

I have made an appointment with a local vintage sound gear technician to troubleshoot and service it next week.

Sanding down the hardened putty

Here is a picture of sanded plywood ends. The plastic wood has harden and sanded down. This is it looks like before painting

Oh boy, sanding is hardwork 😞