Those speed measurement apps are usually inaccurate for obtaining absolute RPM, but the RPM deviation is typically very accurate, depending on the quality of accelerometers in the measuring device and how well the device is centered on the platter. Its also important to verify the TT is perfectly level.
Below are measurements taken by my Samsung S9+ on a freshly restored 1200MK2 using a generic app.
The motor on this TT was optimized to have exactly equal drive current through all 3 phase groups of drive coils. This was done by reinforcing the PCB traces to the coils and installing 0.22R resistors in series to dampen each coil. The cap values were slightly changed to optimize the detection coil lowpass signal. The best W/F to expect from a PLL controlled technics DD setup is about 0.02% p-p.
Hi all, just found this thread which seems to the frequented by many knowledgeable people, so I’m hoping someone can shed some light on something rather odd, well it is to me at least.
I acquired my SP10 mk2 last year and as far as I know it’s only problem is that pesky strobe light, it only works intermittently. One day I might get round to replacing it with the led mod but it’s not something I’m too worried about in the short term.
Now here’s the weird thing, if I shine a torch into the strobe window (even just quickly) when I move the torch away the strobe light is working and stays working until either the speed is changed or the stop button is pressed, although sometimes it stays working even after the buttons are pressed, quickly shining the torch immediately brings it back to life.
What’s going on?
I acquired my SP10 mk2 last year and as far as I know it’s only problem is that pesky strobe light, it only works intermittently. One day I might get round to replacing it with the led mod but it’s not something I’m too worried about in the short term.
Now here’s the weird thing, if I shine a torch into the strobe window (even just quickly) when I move the torch away the strobe light is working and stays working until either the speed is changed or the stop button is pressed, although sometimes it stays working even after the buttons are pressed, quickly shining the torch immediately brings it back to life.
What’s going on?
What you've demonstrated to yourself is that neons need extra energy to strike (which you provided with the photons from your torch). Once the neon had lit a few times, its internal surfaces had warmed and that was enough for it to continue striking. You must be right on the cusp of it being unable to strike. Ultimately, you need a new neon, or (better) replace it with orange LED etc.
When it comes to conceptual ideas for a alternate type of SP 10 MKII main bearing, the Kaneta design really has allowed the levee to break on the ideas that can be put on paper.
Out of all Bearing Design changes I have been involved with and privy to throughout many years, this is the one I have came to believe has the most expectation for producing a discerning noticeable difference.
I feel confident I have presented enough to encourage the support of skilled friends to buy into the ideas presented and produce a prototype to be utilised, the materials and microns to be selected are the concerns of friends.
What has also been discovered is that with a little extra attention, an alternate Platter design is also able to be added, that is not needed to appear in a form that resembles the original.
Out of all Bearing Design changes I have been involved with and privy to throughout many years, this is the one I have came to believe has the most expectation for producing a discerning noticeable difference.
I feel confident I have presented enough to encourage the support of skilled friends to buy into the ideas presented and produce a prototype to be utilised, the materials and microns to be selected are the concerns of friends.
What has also been discovered is that with a little extra attention, an alternate Platter design is also able to be added, that is not needed to appear in a form that resembles the original.
