hi guys
question : like with the SSM chips for the prophet 5 rev 2, what are the “rare parts” for a minimoo D which are good to get now, before they disapear completely ? 
Not many.
Depending on the oscillator card, the UA726 and now CA3046 are getting hard to find. But a lot easier than SSM parts.
CA 3046…$1.10 each at futurlec.com. 
Only the uA726 chip, used on the later oscillator board serials 10175 and above (although some of these boards were sometimes retrofitted in earlier serial numbers), is harder to find because it has been discontinued. And no direct modern replacements seems available (to my knowledge).
Everything else has a modern equivalent readily available.
Some parts are a little more expensive than others, and perhaps a little more difficult to find, notably the LS3954 (direct replacement for E402 dual J-Fet transistors), and some Allen Bradley Type-J pots (notably reverse audio taper used for filter emphasis control).
But these parts don’t have a very high failure rate.
The chip that has the highest failure rate inside a Minimoog D is the very easily available 741 op amp.
All the electrolytic caps are also available, and should be replaced as a preventive measure because of their dreaded rising ESR with age, that can make other parts fail around them (most notably in the PSU).
But I’m sure Kevin Lightner, who has repaired and upgraded more than his fair share of Minis, might have some insight into this as well…
Yeah but did you try to order? The online form bombed on me.
I order from them all the time. Never tried to order that particular chip. Would you like me to try it?
No need to.
By far, the things that will bring down a Minimoog are abuse, non-use and aging.
Age appears to affect three things: electrolytic capacitors, certain styles of resistors and tarnishing of silver plated surfaces which are found in every switch whether rocker or rotary selector. Jacks also have a silver plated hot contact which can tarnish.
Many components get a bad rap for failures, but it’s often some other underlying problem that causes this and not the component itself.
For example 741 opamps and uA726 chips do indeed die.
But they appear to die much more frequently in Minis with still-present old electrolytic capacitors.
Another mode of failure common to 741 chips is tarnish on the legs that can build up to such levels that it can short adjacent pins or eat through the legs themselves.
This only occurs on some chips that feature silver plated legs.
Some components known for failure are also:
Tempco resistors (found on earlier and mid production Minis)
Custom resistor arrays (found only on the later temp-stabilized VCO boards.)
Certain foil capacitors (often brightly painted in stripes) which can crack at their leads.
Rectifiers used on the rectifier board.
Fuses (either old or overburdened by mods, updated VCO board installs, accessories, etc.)
Many failures are mechanical or environmental:
Broken solder connections.
IC sockets.
Worn pots.
Worn switch contacts.
Corroded Cinch connectors (keyboard and mod section.)
Frayed power cords.
Loose edge card sockets, worn or bent pins.
Trimmer adjustments.
Loose screws on the power transistor heatsinks.
Blown lamps (both the neon pilot lamps and incandescent overload lamp.)
But again, by far, the problems most experienced by Minis are not components or rare parts, but age, abuse or neglect.
Environment can play a role also and Minis located near humid areas and beaches may see accelerated corrosion.
Finally, the keyboard itself has several possible failure possibilities.
Bad contacts, bussbars, key bushings, worn pivots and other mechanical or electromechanical causes.
Some people have stepped up to address these various problems and offer new bushings, bussbars and (my own) optical contact replacement system to bring new life to old keyboards.
I don’t recommend hoarding rare parts “just in case.”
This removes them from the market when others have legitimate component failures.
It raises their costs too.
If a Mini is recapped, cleaned, tightened and generally kept in good condition, there’s a good chance an instrument could outlast its owner.
At worst, a Mini can be repaired usually, but an owner will eventually die.
So consider your Mini a little more immortal than yourself and then consider what parts one can save up for their own health… which is virtually nil.
Moral of the story- take care of yourself and your Mini, but if you have to worry about one or the other, a human is much more fragile, irreparable and non-replaceable.
My 3 cents…
KL
As usual Kevin, your 3 cents are worth so much more than that. At least 100,000 times as much ! (minimum current value of a Mini kept in good shape thanks to good advice)
I would add that most of the foibles that Kevin listed can happen to ANY analog synth.
So not using it is bad for the circuits?
Maybe not so much the circuits, but certainly the keyboard contacts and the pots and switches. Especially if it’s stored in a damp and humid environment for a long time. I know all about that… The Mini I finally got my hands on, for a relatively low price, required many hours of restauration on my part due to exactly that by the previous owner.
That’s true of any electronic. Also, smoking is not only bad for your health, but nicotine builds up on circuit boards, and can cause component failure. It creates a blanket over the components, and can cause them to overheat.
Not using it is, as thealien666 says, not good for switch contacts. (and yes, worse if the owner is a heavy smoker.)
This might be better understood when one considers that switch contact and buss bars are self-wiping.
Use them and they self-clean to some degree. This applies to some of the control pots also.
Additionally, the electrolytic capacitors can suffer and the rubber bushings in the keyboard may harden prematurely.
One can often see auctions where the owner said their instrument worked fine before they put it in storage, but later when they took it out to sell, things weren’t working as well as before.
Yeah, but damn if it doesn’t make you look cool.
Not really.
And my mother certainly didn’t look cool lying on her death bed, dying from lung cancer at the young age of 58. Her brother (my favorite uncle) neither, a few years after her… Both chain smokers.
I just hope that second hand smoke, in which I lived the first part of my life, didn’t raise my “chances”, if you can call it that, of developing some cancer.
I’ve never smoked anything in my life, except some Popeye candy cigarettes… 
All I got from that were cavities…
So you see, no matter what you smoke, it’s bad for ya!
Just a joke. Sorry, I’m allergic to emoticons.
If you have never smoked cannabis, I strongly urge you to at least try it. Way safer than alcohol, tobacco, or any prescription drugs. You don’t have to smoke it (but I don’t recommend eating it the first time, try vaporizer), and your perception of music and food and life in general will be enhanced greatly. It’s the most natural feeling in the world. It’s kinda like waking up after the best sleep you have ever had, a little groggy, but feeling euphoric and serene. Cannabis actually improved my physical (and even more mental) health greatly. I figured out about 10 years ago that I could eat anything while stoned. So I would go to the health food store and just get all kinds of gross but extremely healthy food like wheatgrass, sprouted grains, all kinds of veggies, etc. and go home, get baked and gorge myself with health food, and now, I refuse to eat red meat, refined starch or sugar, or any junk food. I think food is incredibly important to music. When I spend time cooking a great meal, then puffing it relaxes me while giving me immense creative energy, and blissfulness that goes into the music I play. They say Miles Davis would alternate cooking and practicing all day.
Of course too much of anything is bad for you, but cannabis is an important medicine for humans (I have a prescription in CA), so much so that we have evolved chemical receptors in our brains for cannabinoids, of which cannabis is the only source. Society tells us to poison ourselves with alcohol, tobacco, chemical medicines for manufactured ailments, and crappy processed food that cause all sorts of disease, but a medicinal herb used for millennia is demonized and classified with poisons like hard street drugs.
Cannabinoid receptor type 1:
CB1 receptors are found primarily in the brain, to be specific in the basal ganglia and in the limbic system, including the hippocampus.[1] They are also found in the cerebellum and in both male and female reproductive systems. CB1 receptors are absent in the medulla oblongata, the part of the brain stem responsible for respiratory and cardiovascular functions. Thus, there is not the risk of respiratory or cardiovascular failure that can be produced by some drugs. CB1 receptors appear to be responsible for the euphoric and anticonvulsive effects of cannabis.
Cannabinoid receptor type 2:
CB2 receptors are predominantly found in the immune system, or immune-derived cells[5] with the greatest density in the spleen. While found only in the peripheral nervous system, a report does indicate that CB2 is expressed by a subpopulation of microglia in the human cerebellum .[6] CB2 receptors appear to be responsible for the anti-inflammatory and possibly other therapeutic effects of cannabis.[5]
I played smokey bars for almost 25 years yet never put a cancer stick to my lips. I eventually “retired” from the gigging scene due to work demands. Some time later it was officially confirmed that second hand smoke is a carcinogen. Among other reasons I don’t think I’ll be going back to bars anytime soon!!!
I remember this one place where there was so much tobacco smoke (this is RURAL Pennsylvania) that my fingertips collected enough dust from playing my keyboards and I had to wash my hands between each set 
And this same place often had a half-eaten hamburger laying in the urinal And when the law was called to the joint the patrons took out their own form of vigilante justice by stealing the officers’ clubs and busted the mirrors and dome/head/tail lights on the police car
I had a big 5-cell Brinkman flashlight that I kept up on stage in case I needed it for a weapon - never needed it 
Don’t worry, my mom passed away 14 years ago. I got over it by now.
I’ve never tried pot. In fact, I don’t drink, don’t smoke, don’t do drugs.
I’ve never felt I needed those things to get the most out of life. I don’t want to distort reality. I want to be fully, and 100% aware of every little detail of it, each and every minute of the time I’m awake. Life is so short.
And what good is getting so drunk, that the best sex you might ever have had the night before, you can’t remember anything about the next morning ?
I have known people who smoked weed, but found them so uninteresting when they were high.
True that some of the best music was composed by people who were on powerful drugs. I’ll give you that. But that had such a high price tag, that many died way too early.
And it’s also very true that smoking a little weed will never really harm you.
But for me, for the time being, it’s: thanks, but no thanks…
Maybe if I do get cancer, then I’ll most probably change my mind and want to get some relief out of it…
Sorry for all the rambling…
What you come to realize from mind altering experimentation is that you have so much more control over your own mind , perception and consciousness than you can imagine. When you speak of “reality” I think you and most people are really talking about the collective human consciousness, which comes from upbringing, media, and interaction with other humans. But I think we all have the ability to create our own reality, if by psychoactive substances, lucid dreaming, meditation, sensory deprivation (really want to try this), etc.
The uncertainty principle tells us that just by looking at something, we change it physically at the wave/particle level. So yes, you will be distorting what you have come to accept as reality, but that can be a good thing, if just for the experience. But this will allow you to get another vantage point of life. If you stay in one spot and try to get a lay of the land, vs. even moving to one other spot opens up your vantage exponentially. So if you have any existential tendencies at all, you might see the “distortion” as a new form of reality, one that can be completely on your own terms.
I know how cannabis affects people, especially when they are novices (which I was 15 years ago), they get tired, dumbed down, forgetful, eat junk food, don’t practice good hygiene etc. But in a way (at least in my case) that can make you smarter, have better memory, more creative, better diet, etc. because it forces you to try harder to keep up (and there being two main sub-species of cannabis, sativa and indica, and fresh organically grown outdoor sativa is like a completely different experience altogether, very few of the bad side effects, it is actually very stimulating, almost like THC and caffeine mixed). Kinda like wearing weights on your ankles while running. Sure it may slow you down and make you tired quicker, but it conditions you to be stronger and have more stamina.
As good as Bob Marley sounds sober, you can’t imagine how good he sounds when you put yourself in his state of mind. And if for nothing else, get stoned and play your minimoog, as I did for I think about 14 hours straight when I first got it. Or listen to Bob Marley AND the minimoog:
http://www.youtube.com/watch?v=nlk9Sj4Ns2k
But if you are happy as is, then fuck it, don’t listen to me.