Hi koldby.
Read page 7 of the manual, that might help regards replacing the O-led display with a larger one.
No doubt Steve will advise on how to proceed.
Glad you got the Controller working for your Lenco L75.
Regards
Ray
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Hi Koldby,
glad you are up and running. You are right there will be a DC offset as the output is direct off the op-amp. For later revisions I will move OP after C11 & C12 respectively which will cure, but its a good point for anyone else using an off board amplifier. Second point for anyone else, use OP2 with just a single drive as the HF noise is lower or implement a low pass filter as Koldby has done. (I will add this to the manual). The reason OP1 / RED output has more HF is due to the proximity of the AD9833 to the processor. Not an issue driving motors and there is later filtering for the on-board drive but Class-D amps may be a bit unhappy. Good points though. Again hoping to move DDS chips further away in a later revision but it's an easily solvable issue with a low pass.
For the display question the software in the microprocessor is coded to use certain types of OLED driver chips so you need to find one with an SSD1306, SH1106 or SH1107 driver chip, I2C (IIC) compatible and it needs to be at least 128x32 pixel resolution. The lettering will not scale to occupy a larger display with more pixels with the current code, so you are just looking for a physically larger display at a similar resolution if you see what I mean. I would suggest a scout of ebay or arduino forums. Try something like this ebay 1.3" OLED (This is 128x64 but a bit physically wider)
When you get to PID tuning can you let the forum know what the optimum values are for Kp, Ki and Kd with your L75. Thanks.
glad you are up and running. You are right there will be a DC offset as the output is direct off the op-amp. For later revisions I will move OP after C11 & C12 respectively which will cure, but its a good point for anyone else using an off board amplifier. Second point for anyone else, use OP2 with just a single drive as the HF noise is lower or implement a low pass filter as Koldby has done. (I will add this to the manual). The reason OP1 / RED output has more HF is due to the proximity of the AD9833 to the processor. Not an issue driving motors and there is later filtering for the on-board drive but Class-D amps may be a bit unhappy. Good points though. Again hoping to move DDS chips further away in a later revision but it's an easily solvable issue with a low pass.
For the display question the software in the microprocessor is coded to use certain types of OLED driver chips so you need to find one with an SSD1306, SH1106 or SH1107 driver chip, I2C (IIC) compatible and it needs to be at least 128x32 pixel resolution. The lettering will not scale to occupy a larger display with more pixels with the current code, so you are just looking for a physically larger display at a similar resolution if you see what I mean. I would suggest a scout of ebay or arduino forums. Try something like this ebay 1.3" OLED (This is 128x64 but a bit physically wider)
When you get to PID tuning can you let the forum know what the optimum values are for Kp, Ki and Kd with your L75. Thanks.
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Hmm
Something fishy about this.
When I start Zeus up without detector attached and have set the 33.3 frequency to 50 Hz it starts at a way lower freq. (around 25 Hz) . And it doesn't change even though I change the frequency..
If I install the sensor it also starts at this low freq. and stays there, Nothing on the graph and zero'es as feedback and output numbers . If I manually push up the speed a bit, suddenly the graph comes to live , with output and feedback BUT no setpoint! And the speed just slowly increases and it keeps doing that.
I can change the behavior of the two (feedback and output) by changing the K parameters, but the result is the same : ever increasing speed.
Something fishy about this.
When I start Zeus up without detector attached and have set the 33.3 frequency to 50 Hz it starts at a way lower freq. (around 25 Hz) . And it doesn't change even though I change the frequency..
If I install the sensor it also starts at this low freq. and stays there, Nothing on the graph and zero'es as feedback and output numbers . If I manually push up the speed a bit, suddenly the graph comes to live , with output and feedback BUT no setpoint! And the speed just slowly increases and it keeps doing that.
I can change the behavior of the two (feedback and output) by changing the K parameters, but the result is the same : ever increasing speed.
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Hi Koldby,
you may be better contacting me by email but I will explain basic operation for benefit of everyone:
The board can operate without a sensor (detector). For this to work you need the setting in the system menu “Are you using PID and platter sensor?” to be set at N. This means the board just works by sending out a set frequency. However, when starting or changing speed (up), it will start about 20Hz lower that the desired frequency and ramp up – a soft start facility. The output will increment over a period of 10 seconds to the full frequency output. If you have a sensor connected it will read and display the RPM on the OLED.
If you are using PID (“Are you using PID and platter sensor?” to be set at Y) then again the starting frequency will be at 20Hz lower than the set-point. It will ramp up as quickly as your turntable and Kp, Ki, Kd parameters allow. It must have a sensor installed and be working correctly to allow this. If sensor is not connected or not adjusted properly to register the platter marker it will never speed up as there is no feedback into the PID algorithm.
That’s why in the manual we say to set the sensor up first and get it reading close to correct RPM’s then switch on PID control. (The serial terminal / software will display the speed as I know you have broken your OLED).
So trying to make sense of what you are reporting in your posts looks to me as though the sensor is not reading properly. That would give you the results you have described. Can you check the sensor is working in non PID mode then enable PID. A couple of screen shots may help if you are still experiencing problems.
you may be better contacting me by email but I will explain basic operation for benefit of everyone:
The board can operate without a sensor (detector). For this to work you need the setting in the system menu “Are you using PID and platter sensor?” to be set at N. This means the board just works by sending out a set frequency. However, when starting or changing speed (up), it will start about 20Hz lower that the desired frequency and ramp up – a soft start facility. The output will increment over a period of 10 seconds to the full frequency output. If you have a sensor connected it will read and display the RPM on the OLED.
If you are using PID (“Are you using PID and platter sensor?” to be set at Y) then again the starting frequency will be at 20Hz lower than the set-point. It will ramp up as quickly as your turntable and Kp, Ki, Kd parameters allow. It must have a sensor installed and be working correctly to allow this. If sensor is not connected or not adjusted properly to register the platter marker it will never speed up as there is no feedback into the PID algorithm.
That’s why in the manual we say to set the sensor up first and get it reading close to correct RPM’s then switch on PID control. (The serial terminal / software will display the speed as I know you have broken your OLED).
So trying to make sense of what you are reporting in your posts looks to me as though the sensor is not reading properly. That would give you the results you have described. Can you check the sensor is working in non PID mode then enable PID. A couple of screen shots may help if you are still experiencing problems.
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Firstly, I hope you have all now received your kits and assembled boards from Group Buy #1.
Secondly:
I am pleased to report KOldby’s issue with the Lenco L75 and off-board amplifier has now been solved. The issue turned out to be that the motor controller board soft start feature. The board starts off at a frequency too slow for the motor/amplifier/transformer combination to reliably get going. This has been solved by adding a minimum start-up frequency setting in firmware v2.2e. The same issue may apply to other shaded pole motor/amplifier/transformer systems. Please contact me for a firmware upgrade if you encounter the issue. KOldby is now getting excellent speed stability results with WOW <0.005% when the system has settled.
Also as KOldby mentions you will need a DC blocking capacitor and potentially low pass filter to feed the Class D amp. He reports 1uf works best for the DC blocking capacitor.
Third, if you wish to join the second group buy then please complete the form in the link.
Regards, Steve
Secondly:
I am pleased to report KOldby’s issue with the Lenco L75 and off-board amplifier has now been solved. The issue turned out to be that the motor controller board soft start feature. The board starts off at a frequency too slow for the motor/amplifier/transformer combination to reliably get going. This has been solved by adding a minimum start-up frequency setting in firmware v2.2e. The same issue may apply to other shaded pole motor/amplifier/transformer systems. Please contact me for a firmware upgrade if you encounter the issue. KOldby is now getting excellent speed stability results with WOW <0.005% when the system has settled.
Also as KOldby mentions you will need a DC blocking capacitor and potentially low pass filter to feed the Class D amp. He reports 1uf works best for the DC blocking capacitor.
Third, if you wish to join the second group buy then please complete the form in the link.
Regards, Steve
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Hi, I will send you a PM with a link to the full manual, there is a BOM at the end. Shipping to Australia for kit or assembled unit is 15 GBP on a 7 day tracked service.
Regards, Steve.
Regards, Steve.
Group Buy #2 closure
Hi,
I will be closing Group Buy #2 at the end of July 2020 so if you are intending to participate please Complete the form
Regards,
Steve
Hi,
I will be closing Group Buy #2 at the end of July 2020 so if you are intending to participate please Complete the form
Regards,
Steve
Turntable Motor controller - Group Buy number 2 update
I am just about to ship the final few remaining orders for kits and finished motor controller boards so you will be contacted soon for final payments.
I do hope everyone has managed to get them up and running without too much difficulty - out of the 60 units I am only aware of one major difficulty after the kit was built which I am sure can be resolved.
I find I have three spare fully assembled boards remaining, so if anyone would still like one please send me a PM.
Hope you are enjoying them - for me I find a huge improvement on timing and space in the soundstage. It's achieved the timing of CD with the musicality of vinyl (and now I don't need to mess around with manual belt changes anymore to play half speed mastered LP's or 12" singles).
I am just about to ship the final few remaining orders for kits and finished motor controller boards so you will be contacted soon for final payments.
I do hope everyone has managed to get them up and running without too much difficulty - out of the 60 units I am only aware of one major difficulty after the kit was built which I am sure can be resolved.
I find I have three spare fully assembled boards remaining, so if anyone would still like one please send me a PM.
Hope you are enjoying them - for me I find a huge improvement on timing and space in the soundstage. It's achieved the timing of CD with the musicality of vinyl (and now I don't need to mess around with manual belt changes anymore to play half speed mastered LP's or 12" singles).
haha - that may have caused a remote diagnosis problem. I don't think I would have started with the opener of "have you put the belt on" 
Glad you got it going and sounds great. Now move onto tweaking parameters for lowest motor vibration and noise.
Glad you got it going and sounds great. Now move onto tweaking parameters for lowest motor vibration and noise.
Regards all.
I received my Zeus yesterday. Very impressed with Stephen's work quality for the project, the manual is very comprehensive and the extent to which the Zeus can be setup with the interphase program is amazing.
Already configured the Zeus for the 60Hz current we use.
Super excited to complete the project as soon as I verify some of the connection and amplification built details.
I received my Zeus yesterday. Very impressed with Stephen's work quality for the project, the manual is very comprehensive and the extent to which the Zeus can be setup with the interphase program is amazing.
Already configured the Zeus for the 60Hz current we use.
Super excited to complete the project as soon as I verify some of the connection and amplification built details.
Years ago I purchased 2 power conditioner cases for a reasonably cheap price. One to use on a battery bank project to power my DACT CT-100 phono stage.
The other to a then "undetermined future project". The class D amplifier to be used with the Zeus has become such future project. So, while waiting for the arrival of some wire and connectors I decided to layout the amplifier main components on the case.
From left to right on the case are the SMPS power connector, the TDA7492 amplifier board, the 2 Triad toroidal transformers stacked, the duplex outlet I will use to to connect the motor cord to the amplifier's output power, the 3 pin connector to wire the existing motor on/off switch.
The other to a then "undetermined future project". The class D amplifier to be used with the Zeus has become such future project. So, while waiting for the arrival of some wire and connectors I decided to layout the amplifier main components on the case.
From left to right on the case are the SMPS power connector, the TDA7492 amplifier board, the 2 Triad toroidal transformers stacked, the duplex outlet I will use to to connect the motor cord to the amplifier's output power, the 3 pin connector to wire the existing motor on/off switch.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.