Dr_Ju_ju

A loose\iffy connection, may well be the cause of your problems.

Also how brave are you ?? As it looks to be close to working, I'd be stripping the camera down & checking all the connections etc. granted there probably not that many, but I'm pat special attention to the imaging chip assembly....

Have you installed Magic Lantern ? if so there are multiple additional choices there....

have you set a countdown ?? & check battery

Yes, that is my understanding, it replaces any external device, but as I don't have one, I can't say for sure....

You'll also then have the PC\USB port connection, so can definitely forget the handset.... I'm almost tempted to get the updated mobo\faceplate as well....

I think that may be a better starting point.... Its also relatively easy to source and easy to change.

Its not Mechanical limiting, Len's point that they could be across the 270ohm resistors, would indicate that the system is current limiting (stepper motors work on current pulses NOT voltage per se), so that at the requested higher slew rates, the appropriate current is not being delivered by the driver chips....

Don't be fooled by current drawn, the published value is just an indication of the maximum the mount will draw when slewing, as this is the time both motors are working 'flat out', and in normal operation will be consuming a lot less.... What you have to ensure is that when the maximum current is being drawn, the supplied voltage doesn't drop below approx. 11v. I've also inadvertently run my mount off a 19v Samsung monitor supply, with no ill effects...

IF you are saying they found a short on the Output side of the chips, and he tested for a short with the motors connected, then he was seeing the motor coil winding resistance which is quite low..... To Identify the capacitors, you'd need a magnifying glass to read what is printed on the capacitor, and yes it will be there.... I still don't know what caused you to start looking at the motherboard in the first place, no movement ??? Just saw your post above, and if it works at slow slew rates and tracking ?? I'd be more inclined to look at the power supply side of the board, where there is an on board regulator, which may well have issues, (I blew one on mine).

Surface mount caps are easy to replace, if you have a good soldering iron with small bits, I do it all the time.... But you still haven't answered why do you think they are blown, what doesn't work ??

Why do you think they are blown, as they are just simple suppressor caps, even available on eBay, or Farnell\RSComponents.....

To my mind, if it doesn't perform to its published specification, then it doesn't matter what the supplier says, its not fit for purpose & should\must be repaired and or replaced.... Other than that, there are tuning services available, or youtube instruction videos for stripping & tuning.

I always keep the originals, then I keep all intermediary files till I've produced an image I'm happy with, but after that they get dumped, as I have the originals all intermediaries can be re-created..

You'll soon need to get a SAN solution e.g. something like this https://www.synology.com/en-uk/products/series/enthusiast fitted with 4\8 TB disks, but will obviously depend on your pocket depth. This then just sits on your network and you can store all the images directly to it.... I have 2 16 TB stores, a Synology Diskstation and a Netgear ReadyNAS, with a smaller Buffalo for use @ star parties....

First off, don't panic.... next thing, do you have another computer that you can plug it into ? also with a different USB3 cable ? if so, install the latest ZWO drivers (v3.0.0.7) & ASIStudio, all available from https://astronomy-imaging-camera.com/software-drivers then do some simple testing there....

How old is it ?? if still in warranty period the supplier may be able to do something...

See PM.....

I'm using a ZWO camera, but for me the Readout noise is set to 1.2

Yes, I do it all the time, when I use that mount, at star parties, or some ad-hoc solar imaging, all easily controlled via either a Windows computer, and even using a Rock64Pro running Indi\Ekos. ..

Nope

There are differences between a v3 handset for the EQ3 & AZ EQ6, and they are NOT interchangeable, I know as I also have both types of mount... It's another reason I only keep the handsets in a draw for sentimental reasons...

Personally, I'd put the handset away and connect the mount directly to the PC using the adaptor. BUT, having said that, as you are using a Prolific based device, you could well have issues with it if the Prolific chip isn't genuine or you are using a new'ish driver. In both cases you will see the same symptoms you describe. I believe the driver to use is "PL2303_DriverInstaller_v1180_20170406" which should then allow a connection. I used to use Prolific devices, but because of the issues you are seeing, I've moved onto using FTDI adaptors, which just work, even if the chips are clones. I make up my own adaptors using these https://www.ebay.co.uk/itm/FTDI-FT232RL-USB-to-Serial-adapt-module-USB-TO-TTL-RS232-Arduino-Cable-6Pin-xe/233513335661 and either fit or rewire an RJ45 standard network cable.

What adaptor were\are you using to connect your PC directly to the mount\handset ?? is it Prolific based or FTDI ??

just above the marked ring, with small thumb screws, there are three equally spaced holes, which allow access to the grub screws.....