There are still refinements to be done; now I can finally take measurements on the real thing in operation and tweak the circuit parameters. Even in its rough state its showing W&F figures so low I'm rather amazed at what I'm seeing: 0.005%. But that is with no groove modulation drag, so it might in fact be right where it should be.
Been revising some maths I haven't done in years to get a few equations that will predict exactly how this thing behaves under various conditions. And writing some software scripts to draw root-locus diagrams for various loop filters. They are still messy, so I'm not showing them off yet!
But we are pleased that you are refining your work!
My no 1 SP10 is due home from a total rebuild incl. off chassis PS/Control unit this next week or so. No 2 will get your treatment but again off-board and comparisons will be very interesting as I will be able to eventually drive each motor from either power/control unit. The plinth is almost ready, slate sandwiched around alloy and a la Mr Kenyeta, i.e. no top plate, just motor and platter in the plinth.
Thanks for all you have done for the few who regularly follow this thread of yours. Pioneer work.
Good luck!
My no 1 SP10 is due home from a total rebuild incl. off chassis PS/Control unit this next week or so. No 2 will get your treatment but again off-board and comparisons will be very interesting as I will be able to eventually drive each motor from either power/control unit. The plinth is almost ready, slate sandwiched around alloy and a la Mr Kenyeta, i.e. no top plate, just motor and platter in the plinth.
Thanks for all you have done for the few who regularly follow this thread of yours. Pioneer work.
Good luck!
I'm also doing an experiment with an unexposed 35mm colour print film. I've cut the sprocket edge off this and affixed it to the platter (possibly other TT platters as well) to see how the sprocket holes will serve as a tacho generator, using a photo diode as pickup.
It seems the film is an easily obtainable source of very precicely punched holes. This could be useful for turntables that have no inherent tacho generator.
It seems the film is an easily obtainable source of very precicely punched holes. This could be useful for turntables that have no inherent tacho generator.
I've updated my page 5 with the details of PLL theory and the maths of optimising the control system behaviour, which I've been typing up and making drawing for over the past few days. It might be tediously abstract for those more interested in circuit boards, but as Carl Sagan said: "If you really want to make an apple pie from scratch, you must first create the universe."
Link --->PLL theory
It's a PDF file - only way I can get equations in.
The graphic on the last page (page 9) is a screen print from the software scripts I've been writing to plot the pole-zero motion (root locus) of the system as the loop gain is adjusted.
The direct link to the PDF ---> http://web.eject.co.za/s8nspawn/sp10web/sp10pllg.pdf
This isn't quite complete; it only covers linear phase detectors, and there is a bit extra on Z-transforms for digital systems, still to be added. The 'Z' in Z-transform is not indicative of the Z-Z-Z-Z-Zs I'l probably hear from readers.
Link --->PLL theory
It's a PDF file - only way I can get equations in.
The graphic on the last page (page 9) is a screen print from the software scripts I've been writing to plot the pole-zero motion (root locus) of the system as the loop gain is adjusted.
The direct link to the PDF ---> http://web.eject.co.za/s8nspawn/sp10web/sp10pllg.pdf
This isn't quite complete; it only covers linear phase detectors, and there is a bit extra on Z-transforms for digital systems, still to be added. The 'Z' in Z-transform is not indicative of the Z-Z-Z-Z-Zs I'l probably hear from readers.
I am sooooo looking forward to the culmination of this project, given the W&F figures you've gotten so far. Be very interesting to see how it stacks up against my elderly Trio L-07D. Please keep up the very fine work!
Cheers, Jon.
Cheers, Jon.
My internet has been out for a while - so I'm now just getting back to message board postings!
I'm currently PCBing/testing a frequency-to-voltage module to add in parallel to the existing digital PLL to see if I can get a wider lock range.
While the PLL as I have described so far works, it doesn't give a very wide control range, so under conditions where it does unlock (heavy load, or at start-up) it is quite slow to get re-locked.
The power-amp section I'm very happy with - I don't think I'll be changing that. But the direction reversal switching will be modified slightly in the future to give improved torqe in reverse.
I'm currently PCBing/testing a frequency-to-voltage module to add in parallel to the existing digital PLL to see if I can get a wider lock range.
While the PLL as I have described so far works, it doesn't give a very wide control range, so under conditions where it does unlock (heavy load, or at start-up) it is quite slow to get re-locked.
The power-amp section I'm very happy with - I don't think I'll be changing that. But the direction reversal switching will be modified slightly in the future to give improved torqe in reverse.
Anyone have sources that already build new controller/PSU for SP10?
Myself, Steerpike, and others first posted to this thread on June 15, 2008..... 2.5 years ago!
This thread receives very rare, and sporatic posting... at best.
Honestly, I don't see this thread going anywhere.
I know I have seen motor contoller units and power supplies built by professionals for the SP10 MKII.
I think it would be much more practical to make a list of these so that we could at least purchase them and get our turntables done.
I will do more searches and try to come up with what I have come across in the past, and hopefully others will chime in with their own sources and we may be able to find built from scratch equipment at affordable prices.
Anyways...I'm just expressing my thoughts....
Rick
Myself, Steerpike, and others first posted to this thread on June 15, 2008..... 2.5 years ago!
This thread receives very rare, and sporatic posting... at best.
Honestly, I don't see this thread going anywhere.
I know I have seen motor contoller units and power supplies built by professionals for the SP10 MKII.
I think it would be much more practical to make a list of these so that we could at least purchase them and get our turntables done.
I will do more searches and try to come up with what I have come across in the past, and hopefully others will chime in with their own sources and we may be able to find built from scratch equipment at affordable prices.
Anyways...I'm just expressing my thoughts....
Rick
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Rick
Your frustration is understandable. I have, in the meantime, found myself a nice Yamaha PX-2, which is keeping me very happy for now. I have sold my SP10s, though I still have a motor that I am keeping for this project (mine will be Kaneda-style plinth).
Except for some Japanese DIYers who built new motor controllers, I have not seen other projects that I consider worthy. I think the power supply-only projects don't really do much more than fulfill the buyer's need for an "upgrade".
I hope Steerpike will find the time to kill this project one time. It seems so close and yet so far...
Your frustration is understandable. I have, in the meantime, found myself a nice Yamaha PX-2, which is keeping me very happy for now. I have sold my SP10s, though I still have a motor that I am keeping for this project (mine will be Kaneda-style plinth).
Except for some Japanese DIYers who built new motor controllers, I have not seen other projects that I consider worthy. I think the power supply-only projects don't really do much more than fulfill the buyer's need for an "upgrade".
I hope Steerpike will find the time to kill this project one time. It seems so close and yet so far...
I too became somewhat impatient and sent my broken SP10 to Vantage Audio here in the UK. Richard has done a superb job and upgraded the PS, repaired the speed control and fitted a screened flying lead to the PS from the motor. Electronics were already mostly off-board: now the remainder and top-plate have gone so that I too can fit just the motor, Kaneda style, in a slate plinth a la Oswald Mills. Even the speed change switching is now off board! You can google Vanguard Audio UK; They are not cheap, but do carry out excellent work.
For those who need a TT in a (comparative) hurry - google <Lenco Heaven>, which is a brilliant site for updating and squeezing the utmost out of the old heavy platter Lencos. Also see Arthur Salvadori on these conversions.....he places the Lenco - done fully and well - above any other TT!!!!!!!!! Pinch of salt or not, it has remarkable potential - and the total cost to covert to the limit would be much the same as rebuilding and replinthing an SP10.
That said, I am sure that Steerpike will get there in the end, but what will be the uptake on building a complete new PS/Controller will I fear not be large - there are a few of us who have followed this thread for its duration, but whether we will actually "get around to it" remains to be seen!
For those who need a TT in a (comparative) hurry - google <Lenco Heaven>, which is a brilliant site for updating and squeezing the utmost out of the old heavy platter Lencos. Also see Arthur Salvadori on these conversions.....he places the Lenco - done fully and well - above any other TT!!!!!!!!! Pinch of salt or not, it has remarkable potential - and the total cost to covert to the limit would be much the same as rebuilding and replinthing an SP10.
That said, I am sure that Steerpike will get there in the end, but what will be the uptake on building a complete new PS/Controller will I fear not be large - there are a few of us who have followed this thread for its duration, but whether we will actually "get around to it" remains to be seen!
I appreciate very much what steerpike has done so far and I'm not refering to his posts specifically, as he has already done more than I would have expected.
When this thread started, I was really wanting to get my SP10's finished, they have been in limbo for over 2 years and I am not getting younger 🙂
I want to get my SP10 motor onto a plinth, with the motor controller/PSU all seperate...and I was hoping to have accurate speed control as an addition.
As per the Lenco/Goldring turntables, I'm very familiar with those, I was one of the first posters on the famous "Home Despo" Lenco thread on Audiogon.
I have a Goldring G99 turntable, an L75, a B55 and spare motors... I have the ultimate RCM (record cleaning machine) powered by lenco motors. It's a Keith Monks KMAL MKIII, a dual platter RCM, pictured below.
I have also purchased a PTP (Peters Top Plate) so that I can build a custom table just using the motor/hardware.
Yes, the Lenco/Goldring is another great option for DIY..
Rick
When this thread started, I was really wanting to get my SP10's finished, they have been in limbo for over 2 years and I am not getting younger 🙂
I want to get my SP10 motor onto a plinth, with the motor controller/PSU all seperate...and I was hoping to have accurate speed control as an addition.
As per the Lenco/Goldring turntables, I'm very familiar with those, I was one of the first posters on the famous "Home Despo" Lenco thread on Audiogon.
I have a Goldring G99 turntable, an L75, a B55 and spare motors... I have the ultimate RCM (record cleaning machine) powered by lenco motors. It's a Keith Monks KMAL MKIII, a dual platter RCM, pictured below.
I have also purchased a PTP (Peters Top Plate) so that I can build a custom table just using the motor/hardware.
Yes, the Lenco/Goldring is another great option for DIY..
Rick
Attachments
Maybe, maybe not. Patience, sometimes life intervenes and hobbies have to take a back seat only to be resurrected later.
Wow, I'd even forgot about this forum or that I had posted here until I got the email notice on a posting in a watched thread. Looks like nothing new has been posted in a long long time. Maybe your bump will spawn the resurrection of the thread.
Hello everyone, reviving this thread cause I'm trying to salvage a SL-D2. The control IC AN630U is blown. Wondering if anyone went ahead and built the controller designed by Steerpike. All the links in his posts are dead, no access at all to the schematics and PCB layouts. Anyone have the schematics and can you please share them?
Thanks.
Thanks.