Sourcing - long USB cable?

erick (Eric) · #1 10-03-2009, 10:35 AM

I did a bit of a search but it was inconclusive. Before I try harder, thought I'd see if I could pick some brains/experience.

I'd like a longer cable to connect my Pentax K100D (scope-mounted) to laptop (on table nearby). Five metres would be good, maybe I could live with three. (currently have three short cables in series.)

At laptop end, it is the standard male A-Type USB plug. At the camera end it is a male micro USB plug. (not the mini).

Anyone have a source? Anywhere in Melbourne where I can walk in, try and buy?

Thanks
Eric

Dennis · #2 10-03-2009, 10:42 AM

Hi Eric

I use a USB extender cable similar to this one.

Mine is only 1.8metres long as that is all I require. I understand that USB can be used up to 5 metres before you require a repeater to boost the signal.

Cheers

Dennis

rogerg (Roger) · #3 10-03-2009, 11:00 AM

I'd just get an extension cable from a local computer or officeworks type store. 3 or 5m. HOWEVER .. a word of caution about length...

I at first had a 5m cable extending my canon's standard 1m cable. This worked 99% of the time but I did sometimes have drop-outs or strange unexplainable behavior. Having strange things going wrong in the middle of the night is frustrating and time wasting so I changed my setup to include a powered hub, so I now have:

PC <---5m cable---> Powered USB Hub <---1m camera cable---> camera

The powered hub is positioned at the telescope and powered by a 12v -> 5v converter. This way I get no drop-outs.

You can get extension cables which effectively have a powered hub at the end but in actual fact it draws its power from the USB cable it self. This usually works fine, but I suspect that in some situations this might leave the device(s) plugged on to the cable with perhaps insufficient power. Just a guess. I think DSE have them.

Also, if you just add a 3m cable to your existing 1m cable then you shouldn't have any problems.

Roger.

ozstockman (Mike) · #4 10-03-2009, 10:55 PM

Hi Eric,

check Dick Smith. They should have 5m USB active cable

I am using two of them and they work fine. Just be aware that you cannot put any other USB cable between this active cable and your laptop USB port as it'll be over 5m which is a limit for USB. However you can connect this active cable to your laptop, then connect any another USB cable(s) to this active cable and finally connect it to your camera.
Also if an extension cable is built well it may be possible to connect up to 6 active cables to reach 30m in length.

The whole idea of these active cables that they pick almost degraded signal at the end of the extension, burst it and repeat it further for another 5 meters.

cheers,

Mike

erick (Eric) · #5 10-03-2009, 11:00 PM

OK, tell you what I have done. It's hard to get anything with the micro USB plug - still a bit too new. So I picked up a basic 5m USB extension cable on the proviso that I could return it and swap for a 3m.

I've tried it on two computers now and it works. Woo-hoo! 80cm cable from camera --> 5m extn cable --> computer. No problem moving files up and down from the DSLR. I think that is all I need, thanks all.

Kal (Andrew) · #6 11-03-2009, 07:09 PM

Not exactly on topic but an interesting tidbit - at work the other day I saw someone connect 7 USB extension cables end to end - would have been a total cable length of maybe 7-8 metres or so. The barcode scanner on the end of it all still worked OK!

mrsnipey · #7 11-03-2009, 10:13 PM

Erick, I know you've already solved your problem but just remember - Ebay is your friend.
I bought a number of 5m USB extension cables a while ago and they work perfectly. Nice and cheap too.

rogerg (Roger) · #8 11-03-2009, 11:35 PM

Quote:

Originally Posted by Kal

Not exactly on topic but an interesting tidbit - at work the other day I saw someone connect 7 USB extension cables end to end - would have been a total cable length of maybe 7-8 metres or so. The barcode scanner on the end of it all still worked OK!

I'm not too surprised it would work for some devices... but cable length is very dependent on the particular device with USB. I bet if you put a canon DSLR on the end and tried downloading an image it'd die. Talking to a RS232 converter/telescope over that length would likely work though.

Roger.

erick (Eric) · #9 11-03-2009, 11:51 PM

Quote:

Originally Posted by mrsnipey

Erick, I know you've already solved your problem but just remember - Ebay is your friend.
I bought a number of 5m USB extension cables a while ago and they work perfectly. Nice and cheap too.

I did a trawl of ebay and didn't quickly spot a USB type A plug to a micro USB plug. The only computer shop I had time to stop in didn't know of one - so I bought the std 5m USB Type A plug to socket cable. $15 - fair enough.