Gina

Well, there shouldn't be but testing on the ohms setting with my DMM shows a short between the +12v power line and the +3.3v data supply line on the HAT. No connection to other GPIO lines such as Gnd or +5v. Later :- Found it! A very thin track on the top of the board started at the end of the +3.3v rail and went along the edge of the board to a pad on the other edge going past where the +12v supply runs. The solder evidently spread to the track resulting in a connection to the +3.3v line. I just hope the RPi isn't damaged. Now to find out.

There is no electrical connection between the GPIO and the power circuits on the HAT - the signals are opto-coupled.

There's a fault with the HAT on the GPIO connector - PSU is current limiting at 5A. I didn't leave the power on for more than a couple of seconds. Unplugged the HAT and tried with just the RPi and current was normal. I shall need to investigate. I guess it was expecting too much for everything to work straight off!!! The ASC will not be ready for deployment today!

Wiring complete (I think) except for extra dew heater - now testing. Firstly, with just the RPi powered from the back converter and bench PSU with just the camera connected via USB. WiFi isn't working but Ethernet connection works. Camera is working and I have focused by hand. Next, I'll attach the HAT and test other functions.

Mine's on my living room table being worked on. I'll be a few hours yet before it's ready to go outside.

Slowly making progress with the wiring. Connector for fan soldered to HAT PCB and wired up. Power wires crimped to ring tags for bolting through the base. Buck converter wired to RPi. Focus motor connector wired to motor and Peltier TEC connected. Having a break to cool off!! It's hot. 28°C here with 45% RH indoors.

New camera support is fine and the lens is at the correct height in the dome. Have camera unit installed with Peltier TEC and waterblock with water pipes connected. Been connecting up but more to do.

There's a shadow but no leg 🤣

Yes indeed.

But they might not dig it right. Might be round instead of square, want it here and they dig it there... etc...

Currently printing a new camera support to fit the new box.

It works out that this box is 3mm deeper than the one I 3D printed so only minor changes are needed to fit the parts in the new box.

Hole cut in lid for the dome with large holesaw on my battery drill, or more precisely for the lens and light to come in.

Could do, yes.

I have already decided to take the water pipes straight out the side. Little chance of freezing with circulating water. I could add a water heater to the reservoir connected to a froststat. And yes, seems sensible to put the electronics inside the box. To take down and indoors means unscrew the bolts on the bracket holding mast to observatory wall, disconnect power cable and one water pipe from the submersible pump. Otherwise, there's a multicore cable and USB cable plus water pipe.

I have a number of decisions to make. The water pipes come out of the side of the waterblock - do I just take them straight out of the side of the box then round in a curve and into the mast pipe, or a sharper bend up round and down inside the box and through the bottom. Do I put the electronics in the box and provide a small fan for air circulation. Reduces the number of connections down the mast to the observatory. Hot weather cooling from the water cooling system - would also keep internal temperature above the outside air and help stop dew on the outside of the dome. May still need dew heater.

The box has arrived and looks alright. I won't say perfect because the seal is in the form of a piece of spongy rubbery string so will have a join. I think I can get round this though by cutting the ends with a craft knife to form a mitre join with silicone sealant. The top is flat so attaching the dome shouldn't be any problem. Next to see how everything fits in and design internal 3D printed parts.

I'm pretty sure the INDI people will sort out running INDIserver and INDI drivers on the RPi 4 in Ubuntu Mate or other suitable OS. I shall be buying an RPi 4 soonish and once I have INDI running on it I'll write a tutorial as I did for the RPi 3B. I have a few other things I'm working on at present but certainly expect to try the RPi 4 in due course. Meanwhile, if others get all this working first I shall be very interested.

I went for Ubuntu Mate as there's a script for it to install INDI etc. in one go. Much less work installing all the bits. Just run the script and answer a couple of questions.

It's not that simple - the display unit also connects to the GPIO. Oh wait, I could replace the back-to-back standard HDMI with a cable.

Ah! I see - that's not good. Didn't notice that. In that case I will need a new cable or adapter and the dedicated display of the RPi 3B won't work with RPi 4

I've always used the HDMI port for display for setting up the RPi. I have HDMI input on my main monitor, a couple of TVs with HDMI and a dedicated RPi LCD display that uses HDMI. I prefer nice big screens as my eyes are not so good with small displays.

I shall probably glue the dome to the lid. The main seal between lid and box will provide access to the works.

Decided to order a box and stop messing about! This box from Amazon, due to arrive tomorrow. 200mm x 120mm x 75mm. Bigger than I need but beggars (buyers) can't be choosers! I might change my mind again and put the electronics (RPi etc.) inside rather than in a box inside my observatory - I'll think about it.

I can't afford a proper cooled astro camera unless I sell some astro kit though it has to be said the the ASC will get far more use than any other astro kit. I shall have a good think about this. I would like to do more astro imaging with lenses and telescopes. Anyway, selling telescopes has the problem of carriage. As I've said, the problem I have with my present ASC is sealing the casing and I'm going to look into the possibility of buying a sealable enclosure. I don't think I want to mess about with pressurising the enclosure - water cooling is bad enough.