DIY 4 Phase Sinewave Generator for Turntable Motor Drive

I only swapped the Up Down wires to the SG-4. Your issue happened to me on previous OEM encoder. How do you find the new encoder over the previous?
All the Arduino encoder pcb (with OEM encoder installed) I bought had one less pull up 10k resistor, I promptly installed one to make it look complete.

For my setup, would be be hard to swap wires on PCB side. All is screwed-in and tighten. I got no complains about generic encoder and replaced for Bourns only for long term quality assurance. Any way, that component will not be in constant use and probably it is overshoot. BTW, my eBay Chinese boards have 3 of 10k SMDs. If I remember correctly, someone clammed here on thread that even two is fine.
 
There's 3 pull up resistors on the Arduino encoder pcb, some may have all three 10k installed, some only two, as in mine. The missing one is designated as R1 on the Arduino pcb and is a parallel connection at R3 on the encoder pcb. Anyone can add a 10k at R3 position if the Arduino pcb one is missing. Its 10k from switch to Vcc. In the case of mine, I can easily buy the required smd resistor and promptly solder it in. I did just that.
 
Here are some pics of my assembled plug n play ready SG-4 Rotary encoder fitted with a quality Bournes encoder.
I also installed pin headers to the SG-4 7 segment output using custom plug in ribbon cables. I felt this is neat and serviceable anytime.
 

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Hi everyone, first time poster here. Firstly, thank you to Pyramid for sharing this project and for your time. I've been lurking through this topic for some times and it has been a really interesting read that gave me some nice headaches as well as I have close to 0 knowledge in electronics.
After seeing all your amazing projects I now feel ready to give it a shot, but I'll surely need a lot of your help so please be patient with me.

I acquired a 24V Rega motor taken off from a new Planar 1 that doesn't have the TTPSU connector. That's why my project would be to build a SG4 based speed controller that would be connected to the motor directly from the amp output in dual phase without output transformers (similar as @jcastellano and @bjps78).

First thing, by any chance does anybody have a spare SG4 board to sell?
 
Thank you, ralphcooke, for your kind offer. After receiving your PM, it is evident that it will be quite expensive to get the preprogrammed microprocessor shipped to Canada from UK, due to being shipped twice across the pond and with the custom duties, etc included in the price. But it may be the only remaining option.

I am just going to try to ask the fellow DIYers on this side of Atlantic if there is anyone who still has some microprocessors (v.1.03) available for the SG4 board.

I know I am very late to this thread, and the action is mostly slowing down by now, but I am hoping I can still get my chance to try this excellent achievement of Pyramid's.

Thanks.
 
Still dipping my toe in the water. I have ordered some of the parts from fellow members (thanks @nezbleu and @vgeorge) so I'm almost ready to start the process.
As I said in my first post, my project will be to build a controller directly connected to a Rega 24v motor. I've found a deal for a second hand 50Hz double pulley and I was wondering if that would work ok with the right settings or if I should better buy a 60Hz version (it will be use in Canada so 110v 60hz wall plug).
 
To my surprise the case that I ordered from China just over a week ago arrived today! Now I guess I have to get serious. I am curious about one thing: what sort of wire and connectors are folks using to go from SG4/amp/xformers to turntable (especially for 2-phase)? I think I saw at least one photo where someone had a panel-mount conventional AC receptacle (where to get those?). I have some 4-pin "aviation connectors" but I'm not sure what their max rated voltage is, and I think the panel connector is male so has pins that could be "live", though I need to check that. They are nice and compact. Any other suggestions to get 115V AC out of the box? Current demands for the Thorens motor are pretty much minimal so I suppose any old 18ga (or even thinner) zip cord should do the trick, though I like the idea of shielding or twisting to minimize crosstalk or EMI.

I still want to mount the speed-change switch and rotary controller on the turntable (the SG4 will be tucked away out of sight); I'm thinking a length of CAT5 will be more than good enough for that, and maybe a cheap D-SUB connector on the SG4 box (and leave the other end captive on the TT). I am also looking for an inexpensive SPST rotary switch, I don't need a Grayhill for this. :)

Any other construction tips/tricks are welcome, or things that caused unexpected problems, or useful parts.
 
Thanks. Everything I looked was pre-drilled and not machined very well. More like a parallelogram instead of a rectangle in the one case I bought.

I've carefully chosen and bought many full aluminum chassis from 3 different vendors at Aliexpress for various projects and recent build of speed controller for buddies (not SG4) and tachometer, finding the quality as described and personal satisfaction to my high expectation at given price. I chose those with blank front and rear panels so that I can have them drilled or machined at will depending on my intended layout. I would have opened a dispute if I found anything not satisfactory or as described. I avoided choosing those chassis with pre-drilled holes for terminal sockets for obvious reasons. I also couldn't risk it all as I've no room for error nor the wait for 3 weeks delivery of another replacement whatever. So far I've been quite lucky I can proceed fitting up everything when delivered. For this SG4 controller I chose something like W260mm X H90mm X D308mm. Could get away with a bit less height or width but I thought the one I chose was best or nearest to what I felt best.
 
I'm not sure whether the link I shared actually works, nor whether the same vendor still sells for the same price or ships for free. The internal dimensions are 300 x 185 x 63mm, I wouldn't have minded a bit more height but it should do. I was very impressed that I placed the order Sunday Apr 29 and it arrived Wed May 9.

Here's another link to the same product (enclosure WA102) : WA102 Aluminum enclosure Preamp chassis Power amplifier case/box size 310*195*70MM-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

In general I go to aliexpress.com and search for aluminum chassis and make sure to select "free shipping"; it might be possible to get a better deal without free shipping but it certainly complicates comparisons.

Answering my own questions about connectors I see Mouser has lots of snap-in panel mount NEMA AC receptacles and they are very inexpensive, so I guess that's the best way to go.
 
I often browse Aliexpress to keep in view of available chassis that I may need in future. Almost all the medium to big sized are never really free shipping. Shipping starts at 25 bucks. If its free shipping for small chassis, the shipping is already calculated in. My past orders were never really with free shipping. Have to add on the shipping charge separately and that makes the product expensive.

I bought this the last time. Its all packed flat and not clam shell design like yours.
Aliexpress.com : Buy Douk Audio Aluminum Chassis Power Amplifier Case DIY Box Combined Enclosure W260*H90*D311mm from Reliable aluminium chassis suppliers on Douk Audio Store
 
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