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1

DIY AstroEQ / Re: Telescope slewing wrong direction

« on: May 07, 2018, 09:09:30 »

don't forget the enter your location correctly in EQMOD.

2

DIY AstroEQ / Re: Stepper motors do not operate - locked and get hot

« on: April 27, 2018, 23:19:59 »

probably the drivers are set to a much higher current than they should. You should adjust the voltage on the drivers to 0.4V maximum if they are DRV8825.

3

General Discussion / AstroEQ parts for sale

« on: April 27, 2018, 08:54:01 »

Tom doesn't want ads on this forum so I have it over at the SGL. Anyone interested can contact me from there;

here is the link: https://stargazerslounge.com/topic/312214-astroeq-bits-and-pieces/

4

Mount Support / Re: Converting early EQ6 mount

« on: January 18, 2018, 20:47:21 »

Just got my  new to me no goto early Atlas mount and took it apart. The original motors have one large toothed cog and appear to have an internal gearbox attached to the motor.

The Goto mount (I have one) has two tooted cogs in an external gearbox. How are you mounting the NEMA motors as if you just bolt them to the old plates and use the single cog it looks as though it will miss the internal tooted cog in the mount. Plus I am not sure the mount would track accurately.

I tool the motors and control board out of my goto mount to try in the early non goto and it worked perfectly. So I am now thinking about how I fabricate the exact same setup in the non goto mount without spending 200 bucks on skywatchers motors which are way overpriced.

why would you need skywatcher motors? any stepper motor would work with astroeq. You just need to find a way to attach the steppers to the mount so that the pulley on the worm shaft could be aligned with the pulley on the stepper. You can make brackets from aluminum or try to use the existing plates after machining them. 

I actually wanted to do this too, but there is no old used eq6 on sale where I live. I think this would be very nice because you can fit all the motors and the board inside mount cuz there is enough space. A few new holes on the front plate for a usb attachment and maybe for a switch, other than that it would look like the original. You can even use the existing power jack and st4 port.

5

Mount Support / Re: Bresser exos 2 mount

« on: November 27, 2017, 13:42:10 »

I plan to use the Nema 14 type proposed by Tom on the website. Are they similar to the one you used (voltage and torque) ?

https://www.pololu.com/product/1200

this is the motor I have used. But even with this the missing steps was an issue hence I had to do the fast decay mod on the DRV8825 driver. So maybe an even higher voltage motor would be better than this. But if it is too high it might stall in high speeds. It is a bit of trial and error. Or you can check other threads on the forum maybe someone had used a motor which didn't miss steps and stall. If you are going to do a DIY board you can also add diodes in to the circuit or use a different driver to solve the missing step issue.

6

Mount Support / Re: Bresser exos 2 mount

« on: November 25, 2017, 23:38:46 »

Thank you.

@ Doramason, did you use Tom's recommendation about type of motors, pulley,... I would be very interesting in having more info on the way you did it.

Regards

it is the same mount as an eq5 so you don't have to change anything. don't buy low voltage motors, they miss steps. I have used 1.8 degree Nema17 motors and 4:1 pulley ratio. Probably it gives more resolution than I need. Thoughest part is attaching motors to the the mount, I have used standard nema17 brackets and pieces of aluminum bar.   

7

Mount Support / Re: Bresser exos 2 mount

« on: November 22, 2017, 19:23:49 »

Hello,

Has somebody tried to adapt stepper motor and astroeq on a Exos 2 Bresser mount. As far as, I read, this mount is very similar (or identical) to a Meade Lx 75.
 suppose the worm gear ratio should be 144:1 ?

Thanks.

I have done and yes it is the same.

8

DIY AstroEQ / Re: DIY PCB and Bluetooth support for Arduino version

« on: October 02, 2017, 09:01:39 »

True, but you only need to use the config utility (USB) when updating the firmware and changing the configuration. You don't need to use it in general running.

The easiest thing to do would be to put a SPDT switch on the RX line of the ATMega. You can use that to select whether the Bluetooth TX pin or the USB IC TX pin connects through to the ATMega.

I was trying to use the VDD line on the USB port to sense when it was connected and do the switchover electrically, but because of the structure of the GPIO pins of the USB-Serial IC (protection diodes), the VDD of the USB doesn't always drop to zero when disconnected - the TX line of the ATMega powers it through the protection diodes. There are solutions, but I haven't had time to investigate.

I have also thought of putting a switch but it didn't seem very practical, there is no space left on the box so it has to be inside. So everytime I want to use USB I have to open the box which can be tricky in the dark.

So I'm guessing you won't be investigating anytime soon . Maybe it is possible to copy it from arduino boards? Because it is possible to use them with both USB and bluetooth without cutting connection.   

9

DIY AstroEQ / Re: DIY PCB and Bluetooth support for Arduino version

« on: October 01, 2017, 22:00:16 »

@Doramason

I never got a chance to get those modules working.

The easiest thing to do from a DIY standpoint is to look how people are using Bluetooth modules with Arduino boards as essentially all you need to do for comms is connect the Bluetooth module up to the UART port on the MCU instead of the USB-Serial IC. Depending on the module you'll also need some level shifting as the MCU runs at 5V and so won't reliably be able to talk to a 3.3V BT module without level shifting.

Yes I have done level shifting with resistors for the HC-05 module's RXD lead, that's how it is connected to Arduino. I'm attaching the schematic I have followed. As I have stated, when I do this with RXD,TXD on the Atmega IC, I can't use the USB connection at the same time while Bluetooth is connected. And config utility only works with USB. You have mentioned a sensing unit which can be used to connect USB while bluetooth module is still connected. Is it possible to add one to the Astroeq? Can you give a basic schematic? 

10

DIY AstroEQ / Re: DIY PCB and Bluetooth support for Arduino version

« on: September 05, 2017, 13:13:33 »

I imagine configuration is not possible because the Bluetooth module will be driving the TX line high so the USB-Serial can't communicate, you'd physically have to disconnect the Bluetooth module to configure via USB or add some sensing circuit. Unfortunately configuration over Bluetooth would not be possible because of the lack of a DTR line needed to reset the chip.

In terms of the purchased AstroEQs, I am actually about to test a prototype Bluetooth module (just waiting for the PCBs to arrive). The AstroEQTooth would simply plug in to the AstroEQ in place of the PIC (USB-Serial chip). I've designed it with a surface mount PIC on it so that you can still use USB without having to take the module out. Plus when you plug in the USB cable it will detect that and automatically disconnect the Bluetooth module allowing control/configuration over USB. There is also an override switch so that the BT can be switched off if not needed to save power.

Hi Tom,

I had the problem also with USB connection not working while HC-05 module is connected to my DIY Astroeq. Hence, I had disconnected it from the board and I have been using the USB cable ever since. But it has the bad habit of disconnecting once in a while in the middle of the night if I accidentally touch it so I prefer a cable-free solution that's why I'm back to bluetooth.

This sensing unit you have mentioned; do you have any schematics for it? Is it something easily can be added with the bluetooth adapter? Does it automatically cut the connection to the bluetooth module every time USB cable is connected?

11

Mount Support / Has anyone tried putting steppers/pulleys on a Losmandy G8?

« on: July 07, 2017, 18:39:15 »

I'm thinking of buying a manual Losmandy G8 mount and putting my current AstroEQ setup on it. However it looks like there isn't enough space on the mount to connect the motors like on the EQ5, especially on RA. I don't want to connect the motors sticking out from the sides with a coupler and planetary gears. But this is just an observation from the photos I have seen. I prefer if someone has better knowledge and enlighten me 

12

Beta Firmware Releases / Re: [Completed] AstroEQ 8.0.3(beta)

« on: May 01, 2017, 12:39:39 »

Hi Tom,

I've downloaded the latest the version to test and I have come across a problem with the goto rate in the config utility. If I enter 600 it is changed to 310, and 800 is changed to 2
I'm guessing something is not right. It used to give quite close numbers.

Could you try the attached version? (copy the attached .exe to replace the one you have)

Thanks Tom, now I can get close numbers.

13

Beta Firmware Releases / Re: [Completed] AstroEQ 8.0.3(beta)

« on: April 30, 2017, 17:51:06 »

Hi Tom,

I've downloaded the latest the version to test and I have come across a problem with the goto rate in the config utility. If I enter 600 it is changed to 310, and 800 is changed to 2
I'm guessing something is not right. It used to give quite close numbers.

14

DIY AstroEQ / Re: How to complie firmware

« on: November 03, 2016, 08:47:37 »

Thanks for the answer Tom. So I'm guessing full steps are not a possibility even with newer firmwares and it is far beyond my capabilities to change. I don't mind the sound or the vibration if I can have higher speeds. The problem why my speed is too low is because of the worm adjustment. If I tighten it to eliminate the end play then motors can't turn that fast. I will try a new set of axial bearings maybe they will improve the situation.

So for the bluetooth, can I just solder the TX/RX of the bluetooth module to atmega and it would work? nothing extra is needed? Like resistors or other components in between? Because I will also do it for my arduino focuser and it requires some resistors. here is the schematic for that. 

15

DIY AstroEQ / Re: How to complie firmware

« on: November 02, 2016, 15:58:44 »

Hi GigiG,

I would like to make some changes to the firmware but I couldn't get a respond from Tom for help I guess he is busy with classes/exams. I hope you can help me with it.

I have a diy astroeq(made with ICs not arduino). I want my motors to run at full step at higher speeds(lets say above 200x sidereal) to have maximum torque. At default motors run at 1/4 microstep which loses some torque so I can't pass a certain speed. Which part of the code should I change and which software should I use? can I do it with arduino software?

another thing I want to add is a bluetooth module like hc-05. I'm guessing additional code needed for that to work plus new pin mapping. have you done it already to your version?