xanthic Posted March 9, 2015 Share Posted March 9, 2015 I've been using a QHY5-II for guiding for a while now and everything was working fine until I upgraded the kit enough so that I can do most things remotely. I've got a decent 15m active USB cable (with repeater in the middle) and the QHY5-II drops out intermittantly, either just locking up or disconnecting. The cable works fine for running everything else without problems, Atik460, Lakeside focuser, mount and filterwheel. Has anyone had the same problem and overcome it? Link to comment Share on other sites More sharing options...
Guest peepshow Posted March 9, 2015 Share Posted March 9, 2015 When I worked outdoors I connected my DSLR camera with a 5M cable to a laptop in a hut. It wouldn't download the images. As I only really needed about 3M length I took a gamble and cut 2M off the USB lead and resoldered the join. It worked OK then. If you don't need all that 15M on your cable you could try shortening it as I did......... ..........I shan't buy you a new one though if it doesn't work. Enquire if any other nuts like me have attempted to do this. Link to comment Share on other sites More sharing options...
Guest knocker Posted March 9, 2015 Share Posted March 9, 2015 (edited) Leigh USB can only run to 5m before drop out hence needing the leads with a repeater in the wiring which you say yours has! -- HOWEVER this is a guide if you are well over 6-7m then it may well not work it depends on the device at the opposite end to the laptop / PC I have QHY5L-II + the QHY USB lead 1.7m Connected to a 5m USB extension (without active repeater) Which is connected to a powered USB HUB Then a 1.5m USB lead to Laptop Unfortunately I have yet to test this out over a nights viewing BUT I have tested it using the full path described above as I have only just finished the build (outside remote scope station) and have been testing the kit out in sittu in the shed, So now that I have seen this post I am thinking what a good idea it was for me to get 2 of these http://www.ebay.co.uk/itm/201169769190?_trksid=p2059210.m2749.l2649&var=500369287049&ssPageName=STRK%3AMEBIDX%3AIT As I knew it may well not work but at the moment its been fine My advise would be to use 2 x 5m with repeaters like the ones above + QHY lead and try that out If the 15m has the repeater in the middle then that's 7.5 which might just be to much for the QHY to handle it might all so be the QHY lost the star or there is a loose connection which means the port will drop out Edited March 9, 2015 by knocker Link to comment Share on other sites More sharing options...
Guest knocker Posted March 9, 2015 Share Posted March 9, 2015 Leigh Have a look at this http://www.eastmidlandsstargazers.org.uk/topic/9110-guide-cameras/#entry102050 It looks like the repeater may be the issue All so my USB hub is powered via the USB port from the laptop NOT Mains Link to comment Share on other sites More sharing options...
xanthic Posted March 9, 2015 Author Share Posted March 9, 2015 (edited) This is an active USB cable that has 2 repeaters along it's length, one in the middle and one at the far end. Last night I was using all my other USB devices without issues using two 10 metre cables chained together (1 repeater per cable). I've done some digging around and it seems I'm not the only one who has had problems with this setup. I'd be interested to see how you get on with yours. I was able to run if for 30 mins last week before it stopped and I was using EZPlanetary so there was no direct connection to the guiding software. Edited March 9, 2015 by xanthic Link to comment Share on other sites More sharing options...
+Graham Posted March 9, 2015 Share Posted March 9, 2015 I have heard this before with the QHY 5 and active repeater cables. It would seem they dont mix that well. I use a mains powered hub on mine an have had no issues (as yet ) Link to comment Share on other sites More sharing options...
Smithysteve Posted March 9, 2015 Share Posted March 9, 2015 Hi Leigh, as per Neil's (Knocker) earlier post, the following info are general rules, (most of this is available on Wikipedia etc.) The USB 1.1 standard specifies that a standard cable can have a maximum length of 5 meters with devices operating at Full Speed (12 Mbit/s), and a maximum length of 3 meters with devices operating at Low Speed (1.5 Mbit/s). There are several other speed too :-) USB 2.0 provides for a maximum cable length of 5 meters for devices running at Hi Speed (480 Mbit/s). The main reason for these limits is the maximum allowed round-trip delay of about 1.5 μs. If USB host commands are unanswered by the USB device within the allowed time, the host assumes the command is lost. The USB 2.0 spec requires that cable delay be less than 5.2 ns per meter, which is close to the maximum achievable transmission speed for standard copper wire transmission systems. Also there are several types of USB cable, they don't all work on all levels of USB (1.1, 2.0, 3.0 etc). Similarly network cables are limited to 100m, and RS232 serial cables about 15m (50ft in my day). Less is better. :-) try to ensure the cable types are compatible and as short as possible to avoid drop out. Link to comment Share on other sites More sharing options...
xanthic Posted March 9, 2015 Author Share Posted March 9, 2015 I appreciate the specs say 5 metres but this is an active cable not a passive. I suspect the camera just doesn't like being run over that type of cable and I'll probably have to switch to a different model. Link to comment Share on other sites More sharing options...
red dwalf Posted March 10, 2015 Share Posted March 10, 2015 i`m not a massive fan of active repeater cables, they have there place but i`ve found anything over 5 meters and your in trouble, they seem to work one night and not the next, some equipment works fine with them and others not at all, one way to maybe get around the situation is to setup as before with shortest cables possiable with maybe a laptop outside running the kit and then use team viewer, which is free, to remotely access the setup. my guide camera was so slow with active usb cables, but what did help me on my old desktop pc was to fit a usb 2 pci card to the rear of the computer, i plugged the guide camera into that and used a non active 5 meter usb cable with a 1.2 meter printer cable plugged into that and it now flies, i use it for planetary imaging as well and at full frame does just over 17 fps easy, before i was getting 3 or 4 fps on a good day. Orion 1 Link to comment Share on other sites More sharing options...
xanthic Posted March 10, 2015 Author Share Posted March 10, 2015 I was trying to get away from having the laptop outside but might have to go back to that unless something like a Lodestar works ok over a longer cable. Link to comment Share on other sites More sharing options...
Sheila Posted March 10, 2015 Share Posted March 10, 2015 I have worked with both short (non active) and long active cables and had no trouble with either. BUT i use a lodestar so this may answer the problem or not, cant see why it would make a difference but I have no issues with the 15m active USB Orion 1 Link to comment Share on other sites More sharing options...
red dwalf Posted March 10, 2015 Share Posted March 10, 2015 have you tried using 2 cables ? dedicated one for the qhy only. Link to comment Share on other sites More sharing options...
xanthic Posted March 10, 2015 Author Share Posted March 10, 2015 I've tried a dedicated cable and made sure it's on a separate bus to the other kit. And a USB2 port too, to make sure there are no compatibility issues. All suggestions gratefully received Link to comment Share on other sites More sharing options...
Daz Type-R Posted March 10, 2015 Share Posted March 10, 2015 All suggestions gratefully received Visual ??????? Then you wont have all these problems..... (Sorry, I`m not helping). Link to comment Share on other sites More sharing options...
xanthic Posted March 11, 2015 Author Share Posted March 11, 2015 Who says I don't do a bit of visual now and then! Link to comment Share on other sites More sharing options...
Sheila Posted March 11, 2015 Share Posted March 11, 2015 Who says I don't do a bit of visual now and then! :o Link to comment Share on other sites More sharing options...
Orion Posted March 14, 2015 Share Posted March 14, 2015 I bought several 5m active cables for my canon 1100d to a 2005 dell inspiron 6000 xp laptop in the house. Ive tried it with 1x5m and works fine. 2-3 cables, there was the odd disconnection in APT. I did notice the tightness of the connections is not consistent, with one feeling too slippy, as if the slightest movement might cause them to start to loosen or even pull apart from a trip over the cable. Not sure if this less tight connection would make a difference. But I prefer my cables to home hard and won't pull apart with gentle force. The slippy connection would pull apart with gentle force. Is there a way to tighten the connection? Such as a crimper tool, or what is needed to be done, pliers? Link to comment Share on other sites More sharing options...
Smithysteve Posted March 14, 2015 Share Posted March 14, 2015 Hi Derek, I am an electrician and have worked with data cables for donkeys years! I would not tamper with the contacts, if it works don't mend it :-) I would bind the two suspect cables together with tape, tyraps (zip ties), or heat shrink sleeving if you can afford for them to be a more permanent connection. Link to comment Share on other sites More sharing options...
Guest knocker Posted March 14, 2015 Share Posted March 14, 2015 I bought several 5m active cables for my canon 1100d to a 2005 dell inspiron 6000 xp laptop in the house. Ive tried it with 1x5m and works fine. 2-3 cables, there was the odd disconnection in APT. I did notice the tightness of the connections is not consistent, with one feeling too slippy, as if the slightest movement might cause them to start to loosen or even pull apart from a trip over the cable. Not sure if this less tight connection would make a difference. But I prefer my cables to home hard and won't pull apart with gentle force. The slippy connection would pull apart with gentle force. Is there a way to tighten the connection? Such as a crimper tool, or what is needed to be done, pliers? With the cost of 5m USB cable I would just get a new pair (or 1) I mean its done then no worriers Its the sort of lead that's like a spare light bulb you will always need it Link to comment Share on other sites More sharing options...
Allan the Plumber Posted March 15, 2015 Share Posted March 15, 2015 Just to add my 2 penny's worth I have 3 active usb cables wrapped in a loom running from mount to summer house each of these cables has 2 active repeaters built in total length 15m I run the mount QHYII camera Atik filter wheel and hitecastro auto focuser through a powered hub into usb cable then to laptop the other 2 cables are one solely for the Atik 314l and the other to the lakeside motor focuser! This set up allows me to either disconnect an item if it crashes with out effect the other programs and hardware running also I now try and leave things pluged in apart from where they're pluged into the hardware this for me (touch wood) seems to be working fine and I am not getting the issues I originally had with my active usb cables due to length etc Link to comment Share on other sites More sharing options...
+Graham Posted March 15, 2015 Share Posted March 15, 2015 I have been doing a bit more digging into this and have come across some interesting facts about the QHY5ll. It would seem because it runs at the extremities of the USB 2 bandwidth any drop off in the signal due to duff connections or cable length will cause it to 'drop out' The manufactures advice is to keep the cable run as short as possible or to use only their recommended repeater type cables. Link to comment Share on other sites More sharing options...
Guest knocker Posted March 15, 2015 Share Posted March 15, 2015 Nice Allen, That's pretty much how my setup is running all be it not more then 10m from device to laptop, I have a dedicated 4 port HUS hub on the tripod legs fixed which leads to a USB/240v outside mains box which then leads under the ground to the shed (cabin) inlet which connects to a second USB HUB inside which is connected to the laptop. As you say the less I need to unplug at the end the better, Link to comment Share on other sites More sharing options...
Guest knocker Posted March 15, 2015 Share Posted March 15, 2015 I have been doing a bit more digging into this and have come across some interesting facts about the QHY5ll. It would seem because it runs at the extremities of the USB 2 bandwidth any drop off in the signal due to duff connections or cable length will cause it to 'drop out' The manufactures advice is to keep the cable run as short as possible or to use only their recommended repeater type cables. Good advice Graham but I would just add this spanner to the works USB is a STANDARD and as such all USB repeaters should in theory be set to that standard but as we all know that's never the case My advice to anyone out there with USB issues is set the device up on a dedicated port first direct to the laptop so a 1m lead test that then add length 1 part at a time test that doing this you will eventually come across the cause of the drop outs if any in which case you will know what to upgrade or swap out Link to comment Share on other sites More sharing options...
xanthic Posted March 15, 2015 Author Share Posted March 15, 2015 I have been doing a bit more digging into this and have come across some interesting facts about the QHY5ll. It would seem because it runs at the extremities of the USB 2 bandwidth any drop off in the signal due to duff connections or cable length will cause it to 'drop out' The manufactures advice is to keep the cable run as short as possible or to use only their recommended repeater type cables. That's something I've come across too. Webcams seem to use a lot of bandwidth and even running it via EZPlanetary I've not been able to run it for long periods of time successfuly. Unfortunately I can't currently have anything shorter than 15 metres so I've made an early upgrade and purchased a Lodestar. Link to comment Share on other sites More sharing options...
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