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
Dear Dover,  To ask a question or to wonder is not to "trivialize".  The basis for learning is questions and answers. That's about all I can say to you that is not vitriolic.  I would hope that JP appreciates the fact that my earlier post meant him no disrespect at all.  In fact, I am rather amazed at his work, since failure of the MN6042 has been the downfall of many Mk3s.

Dear JP, I now see that you did in fact respond to my question about the accuracy of your circuit vs that of the MN6042.  Sometimes these threads move too rapidly for me to be current. I did wonder whether 262.XXX kHz was the operative number or whether it was the much higher frequency that gets divided to yield 262.XXX kHz.  Now I know it is the latter, which enhances the significance of the difference between your circuit and that of the MN6042.  What's additionally appealing about your circuit is the fact that if it ever should fail, it's fixable with parts that are readily available.
I still have question about the other chips inside the MK3. Are they easily found, not as important or just don't ever die?
rower 01-22-2016 1:19pm
I still have question about the other chips inside the MK3. Are they easily found, not as important or just don't ever die?

Someone like Bill T would have better first-hand knowledge, but in my research nearly all the examples I could find that had DN860 or AN660 failures had tell-tale signs of prior work that didn't appear very impressive.  I just didn't see any evidence of "spontaneous" failures for any of the other ICs like you do for the MN6042. 

The motor drive IC, AN640G, is still plentiful, but those don't seem to ever fail.  AN660s and DN860s still show on eBay once in a great while as have a couple MN6042 recently, but they're becoming few and far between unless you strip a lower model 'table. 

Not as easy as the MN6042, but I think something could be fairly easily made to replace the DN860.  That's not to say I think it'd be worthwhile though.  I've a bit over two months and well north of $1000 in to the MN6042 replacement. 

JP
If you ever get tired of your SP10MKIII endeavors, there are
a few anxious owners of Victor TT101,s hanging about.

The thread posted by Halcro previously "audio16" shows what
its all about.
Lewm has one that is currently not operable.
Interesting.  The SC3042 IC is similar to the MN6042.  Not sure it's worth while, but happy to have the conversation.