Vintage DD turntables. Are we living dangerously?


I have just acquired a 32 year old JVC/Victor TT-101 DD turntable after having its lesser brother, the TT-81 for the last year.
TT-101
This is one of the great DD designs made at a time when the giant Japanese electronics companies like Technics, Denon, JVC/Victor and Pioneer could pour millions of dollars into 'flagship' models to 'enhance' their lower range models which often sold in the millions.
Because of their complexity however.......if they malfunction.....parts are 'unobtanium'....and they often cannot be repaired.
128x128halcro
As regards JP and the TT101, I can only report that my TT101 had an intermittent glitch that persisted for the first 3-4 years of my ownership, even after replacing all electrolytic capacitors. (I got it cheap, because it was "broken".) The diagnosis eluded two very competent technicians over that time span, until finally I came upon JPs thread on DIYAudio, wherein he was talking about his new chip for the Technics SP10 Mk2 and Mk3. I detected that he had a deep understanding of these circuits. I contacted him and soon thereafter shipped my TT101 to him in NYC. Within two weeks or so he had localized the problem to a microscopic crack in one of the PCB tracings. Shortly thereafter, my unit was up and running, and I have had zero problems ever since, all because JP has the smarts to reason out where the problem ought to have been and then to locate it shortly thereafter. So, Bestgroove, if I were you I would waste no time in sending the TT101 to JP. My unit was the first TT101 he had ever seen in the flesh, by the way. Very impressive.
@pbnaudio @Lewn

I do not know grand master JP but, I’m sure, I can not and I do not want to send the turntable to the world; I live in Italy and would have an exorbitant cost of shipping, repairing, customs and taxes; I have to fix it and restore it completely and I have to do it yourself.
I’ve already got the service manual and I have a look at the two big mother board .... there will be a lot of work for me next winter and I hope there are no custom made ICs for this turntable.

I already have a decent experience with the Techncs SP 10 II ..... I have restored a pair with their power supplies by disassembling all screw on the screw (even the engine) I had to repair broken tachometer coil wires, and put everything completely new and two others are under construction.

All this is just for passion and because I love collecting old high-level turntables that would end up in trash because they're broken. :)



for example this is 3ad my last restoration with more photos If you are curious.......
http://forum.videohifi.com/discussion/375892/technics-sp-10-mk2-inizia-il-restauro-refurbished-e-fin...



@pbnaudio 

ooopss ....I forgot ..... for plinth there are many great looking photos on the internet and you tube for the TT 101 and others will arrive, but before the turntable will have to work, otherwise it's all worth having a nice plinth and broken turntable.  :(
Best groove, I did not realize you live in Italy. (Lucky for you, by the way.) I don’t know about cost of round-trip shipping to JP in New York City, but I do know that his repair work is very reasonable in cost, surprisingly so in relation to his skill set. The TT101 circuit is very complex, given the "bi-directional servo" system, so I wish you best of luck in figuring out the cause of your problem. You might benefit from talking to JP, even if you feel you cannot afford to ship the TT101 for repair. There are several chips in there, but one and only one of them is the main controller. Of two "broken" units that I know about, including mine, neither of them needed a new chip, fortunately. But I may be able to help you out if it turns out you do need a new controller chip.

Definitely you should start out by replacing all the electrolytic capacitors, unless you know for sure that this has been done recently.  The lifespan of an electrolytic is typically less than 30 years, and shorter still if the unit has been sitting for many years without power.