w7ay The flat ribbon cables are useless for high speed data.

Apart from the one that failed, I really haven't seen any problems with using the ZWO USB 3 flat cables.
I've run them at 200 FPS for planetary without dropped frames and for 120 second subs no problems. I can't put my finger on any problems the ZWO flat cable has caused in normal operation. I like that the cable is very light and flexible and I do coil them up when they are too long.

Sure, they are not "Space Rated" or made from "Weapons Grade" copper, but nothing on, or under my telescope is perfect.

For me, time and money are limited, so before I spend either on telescope or mount improvements, I ask myself one question, "Will this improve my final images?"

So, if I spend the time finding the "perfect" cable, and spend the money on it and shipping, will I get better subs?

Steve.

@tech@zwo I'll happily use a replacement cable.

    StevenEvan
    Please send the mail again and attach the link of this post then we will know. Thanks!

    Thank you for your answers and indeed this could be the USB cable although the issue did not seem to exist a few months back so it also looks like something got degraded in the ASIAIR Pro itself. I wasn't able to test a different cable and I only have another flat cable from ZWO (provided with another camera I bought). In my next imaging session I will test that other cable and see if that makes any difference.

    Per Chen's post it might not make a difference if the ZWO cable is replaced by another ZWO cable. The problem is also somehow random and difficult to reproduce.

    @w7ay may I ask you if you have a cable reference (such as on Amazon for example) that I could use? If not I will just google things up. Thank you very much! I can't wait to solve this issue that's been crippling my astrophoto sessions.

    • w7ay replied to this.

      Not sure if I mentioned this but whenever the issue appears and the main camera gets disconnected, the EFW filter wheel remains connected all while being attached through the main camera hub. This would speak against a physical problem IMHO. Again I will try with a different cable and will report the observed results.

      @tech@zwo - as a workaround it would be great if a future release of the ASIAIR Pro firmware could reconnect the camera without manual configuration or, at least, keep Cooling active by default. One of the most costly (time-wise) parts of those pesky disconnects is that Cooling goes off and it takes a few minutes after the manual reconnect and the manual switching on of Cooling before the temperature is back to the required value (e.g. -20°C).

      Jan75 may I ask you if you have a cable reference (such as on Amazon for example) that I could use?

      With USB 2.0 Type B to Type A connectors, just look for the Amazon ones that has drawings to show that each USB Data pair is a twisted pair and individually shielded (in the Ethernet world, they are known as STP -- for Shielded Twisted Pair, as opposed to UTP, unshielded twisted pair). Then look for the power carrying pair to have a thicker gauge than the data pair.

      Most of the USB 3 Type B to Type A cables are already pretty thick (necessarily so because they are meant to carry fast data, and with extra data pairs). I have found that as long as I stick to shorter lengths (a meter or two), they all appear to work.

      Don't let the thick cables dangle from your connector, I strain relieve my cables and fold them back towards the telescope mount, and from there towards the ground to a waterproof box at the base of the tripod when I have my electronics. See post 322 on this thread:

      https://bbs.astronomy-imaging-camera.com/d/8149-asiair-user-feedback/188

      Chen

        w7ay Thank you, Chen, this makes a lot of sense to me - I didn't mention it but the USB cables did show some wobbling on the AAP end (in fact, in the dark, I could even see tiny sparkles sometimes - I'm almost sure it's not a great thing!). I also take your advice to heart to secure the cables so they don't dangle and their weight pulls even more on the connectors. I found a 1m USB 3.0 A-B cable on Amazon that looks sturdy and has a round profile (which might mean it has twisted cables in it - sadly the description did not mention anything about them) so I'll use it to do some testing. All my cables are velcro attached to the mount with just enough play to let the mount operate - thank you for the pictures in the other post, quite inspiring.

        • w7ay replied to this.

          Jan75 I could even see tiny sparkles sometimes - I'm almost sure it's not a great thing!

          Ouch! That is not good. In my case, the ASIAIR is inside a waterproof box, strapped to my tri-pier, so no wire movement.

          In your case, I would liberally use Gaffer tape, on top of strain relieving the connector by folding the cable back over the body of the ASIAIR and either tape it or use cable ties. Your velcro idea works too, as you can tell from my pictures of strain relieving the cables to my camera.

          USB connectors are designed for use on a desk top and at room temperature. Most of them are nor spec'ed to below 0ºC, and temperature would affect the connection integrity too. I also use silicone insulated zip wires that don't stiffen in the cold.

          Speaking of velcro I recently asked deepskydad to make me some 3D printed strain relief rings for the 3 different ZWO camera diameters that I have, and he has already prototyped one and made a YouTube video :-)

          https://www.youtube.com/watch?v=QV9MLETaBTA

          If that ring does not hold the wires securely, nothing will :-).

          Chen

            w7ay Haha I know right! Seriously speaking, this discussion has been eye-opening to me on this issue that I've been neglecting (being focused on the more "noble" parts of the setup first): quality and stability of physical connections. Deep Sky Dad's video (thanks for pointing me to it) also shows that he used round profile (presumably twisted wire) USB cables, not those supplied with the camera. His rig does look sturdy but indeed I think I will just use the velcro for starters.

            Still waiting on my USB 3.0 cable delivery before I can test it in lieu of the ZWO flat ones and see if the issue is still present or not.

            4 days later

            So I was able to run two tests, one without tracking, just to create daytime darks, and one as a live session shooting an actual target. I didn't have any disconnects in those sessions. I am not saying the issue is solved because it was so random that after just two tests I cannot yet rule out that it happens again but it is clearly promising: the round profile (most probably twisted pair) USB cable seems to have made a difference. Thank you, @w7ay Chen! I also secured both ends of the cable with strong velcros so the connectors remained stable.

            Reporting after 5 different shoots totaling a few hours - not a single disconnection observed. So it WAS the cable, I confirm. Big thanks to @w7ay ! 😄

            2 months later

            I know I am late the the party here guys, but I am on my first night with the ASIAIR Pro, and I can't even get the 120 Mini Guidescope in focus before I get a "Lost Connection" error and have the hard-reboot the ASIAIR Pro to get it to recognise the camera again - pretty frustrating. I had the main 2600MC disconnect once also.

            @w7ay - I read your cable advice with interest and I'll be going to buy a new set of data cables. Can I presume the actual power cables (5.5 x 2.5 barrel connectors) are ok?

            I found this excellent website which seems to stock quality cables in the UK, and I think they have US site too.

            https://www.digikey.co.uk/en/products/filter/usb-cables/455?s=N4IgjCBcoMwJwCYqgMZQGYEMA2BnApgDQgD2UA2iACxgAcVAbLSALrEAOALlCAMqcAnAJYA7AOYgAvsQC0EaCDSRBAVyKkK4WnFYdukEFOkgkkSgFVeAIQAEAYUwAjbPlaSgA

            https://www.digikey.co.uk/en/products/filter/usb-cables/455?s=N4IgjCBcoMwJwCYqgMZQGYEMA2BnApgDQgD2UA2iACxgAcAbAAwDsIxNDCEAusQA4AXKCADKAgE4BLAHYBzEAF9iAWgjQQaSBICuRUhXC04IXiEHDFSkEkiUAqiIBCAAgDCmAEbZ8JhUA

            On a connected note, and I know this is not an iOptron forum, but is there any advice on how to wire up and power:

            iOptron CEM40
            ASIAIR Pro
            ZWO 120 Mini Guide Cam
            ZWO 2600MC-Pro
            ZWO EAF 5V (no power lead, just USB)
            2 x Dew Heater Straps

            There are so many options on what to power what from where...

            In a quirk the ASIAIR can not control a new CEM iOptron mount if it is connected directly to it - the ASIAIR needs to be connected to the mount VIA the 2600MC Camera USB hub.

            • w7ay replied to this.

              mrflib Can I presume the actual power cables (5.5 x 2.5 barrel connectors) are ok?

              Most hobby astronomy devices use 5.5x2.1mm axial connectors. The 2.5mm ones can carry more current, but the center pin will be too loose when the plugs are plugged into a 2.1mm jack.

              Chen

              mrflib I found this excellent website which seems to stock quality cables in the UK, and I think they have US site too.

              Not only do they have a US site, they are headquartered in the USA.

              Their name came from their beginning -- suppling amateur radio hobbyists (I am one) with digital keyers (the stuff that automatically generate a series of dots and dashes so that you don't have to create individual dots and dashes yourself with a simple Morse code key.)

              I tend to use Mouser Electronics more often since they are closer (in Texas) to me, and ground shipping is faster. Mouser was acquired by Berkshire Hathaway -- Warren Buffet's holding company -- a few years ago. I still use Digi-Key for parts that Mouser does not stock.

              Chen

                w7ay

                I've found replacement USB cables taking your advice looking at shielding, AWG and datasheets. Unfortunately, they're all quite a bit longer than I need so I don't really know about cable management. Any tips on this? Can they be bunched up or coiled? Everything is shielded and 24AWG+.

                I have a 3D printer and some CAD skills, but not really design skills - perhaps I can come up with something.

                In case anyone else stumbles on this thread in the future, these are the cables I'm looking at (USB only).

                I am struggling to find quality DC/DC 2.1mm power cables less than 2m in length. 2m length would really mess with the cable management. Any tips on that? Can these cables be coiled also?

                Cheers mate.

                • w7ay replied to this.

                  mrflib Unfortunately, they're all quite a bit longer than I need so I don't really know about cable management. Any tips on this?

                  You should be able to find USB cables of various lengths at Amazon. The power runs are not a problem since you can just cut to what you need and assemble the ends.

                  By the way, for major runs, I use PowerPoles and only reduce to the 5.5mm/2.1mm when it is needed at the devices.

                  Prettiness is not a problem, the electrons won't know any difference. But length definitely is. Use the shortest cable that you can find.

                  And be sure to strain relief the ends. Do not allow the connect jacks to be the ones securing the ends of the cable. Velcro or cable tie the cable ends to some solid anchor and only then plug them the jacks. Here is an example of what I did:

                  You can actually see a dab of Gorilla glue seeping out of the end of the power connector. I had to ream out the original holes so that the connector would take a 18 AWG twisted pair. The glue both fills up any void to help reduce any moisture.

                  A few months ago I had deepskydad.com 3D print some camera rings to hold the cables instead of using velcro and this is what they look like. Pavle told me to he might be offering them for the public (he had in the past done a number of custom things for me, like focusing rings for a Sigma 135ART lens), but since you have a printer, you can fashion your own:

                  Good luck.
                  Chen

                  mrflib I am struggling to find quality DC/DC 2.1mm power cables less than 2m in length. 2m length would really mess with the cable management.

                  I assemble my own 5.5mm/2.1mm terminated cables using 18 AWG pairs and silicone insulation, like this:

                  https://www.amazon.com/gp/product/B0779QRR58

                  The wires on this one looks like 18 AWG, unlike some of Amazon stuff that is advertized as 18AWG but are really more like 22 AWG. The silicone insulation prevents the cable from becoming stiff in the cold. The same brand is on Amazon with longer spools and various AWG.

                  CCheck tables on the web on the resistance per meter for stranded copper wires. Since we tend to run about 5A through the wires, the IR drop can eat you alive with longer cable runs, eespecially if they are thinner than 18AWG. Remember that for each meter of power cable, you need to double the resistance from the power cables for both the power and the return.

                  By the way, for the PowerPole connectors, I use the custom crimping tools instead of soldering -- which can cause the cable ends to become brittle over time.

                  Chen

                  8 days later

                  Found this on Etsy(see link), might be of interest to anyone reading this thread and thinking about cable management and strain reliving the USB cables. If link doesn’t work search ASIAIR on Etsy, the shop has 2-3 varieties/options.

                  https://etsy.me/3uDq0VG

                  2 years later

                  I am having the same issue with my new asi2600mc pro. I am running the AM5,Asiair plus, and asi2600mc pro with separate zwo 12v 5a power adapters. I can't get past 5-10 images taken without the main camera disconnecting. I am posting a new report on this.

                    JSTAR0057 I can't get past 5-10 images taken without the main camera disconnecting.

                    Do you mean the main camera disconnects every 5-10 images?
                    We recommend that you try replacing the USB cable.

                    Try using shorter USB cables as they have a stronger signal. Make sure you are using the right ports USB2 for USB2, USB3 for USB3, and make sure they plugs are tight. I kept losing connect to my guide scope because a) i used wrong USB port, and b) USB-C wasn't plugged in tight enough.

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