USB Cable type in retractable adapters - Page 1
Forum section: electronics / repair

author: Harimake
author_rank: Contributor
timestamp: August 10, 2022, 04:44:15 am
content: I'm looking for a thin flexible flat USB 1.1 - 2 cable. One side USB-A, the other - pigtale. Not shielded, just four wires.The best match would be the type that's in retractable USB cables like these:Does anyone know what type of cable this is?

author: Harimake
author_rank: Contributor
timestamp: August 11, 2022, 08:03:37 pm
content: Anyone? Any guesses?I'm just trying to figure out the type of cable used here...

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2022, 08:15:45 pm
content: It looks like some kind of flat 4 core cable - similar to what is used for phone / modem flying leads in the UK (I don't know about the US). Try a search for modem cable. Without a screen and controlled impedance, it won't meet the USB spec, but it is probably ok for USB1.1.I think the fitting of the molded on USB connectors would have been a custom job for that particular item, I suspect that you won't find a USB-A cable with anything other than standard round USB cable - but who knows what you may be able to find from China. Maybe you can source some more of those retracting reels, dismantle them and cut the other plug off (don't know your application and volume) - as I say, non-compliance (including EMC) may be an issue.

author: Harimake
author_rank: Contributor
timestamp: August 11, 2022, 08:31:22 pm
content: I think I know what you mean by modem cables. In fact I have a few of them laying around from the good old days. Those are quite a bit larger and stiffer.These ones are much thinner and very flexible. Almost looks like rubber casing.I can buy those retractable things from China really cheap and source the cables out (need just a few).The problem is that they are much shorter than what I need...Hoping to find out what they are called and see if there is anything in bulk on aliexpress.Here's a good short close up video to help understand the scale:Here's a close up of the cable:

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2022, 08:45:46 pm
content: Sorry, I've seen really thin flexible cable in retractable modem ones in the past, but not seen anything ribbed like that. Beware (assuming you find some) that increasing the length significantly may give you increasing issues with signal integrity and voltage drop.P.S. I see three ribs. Maybe it's Vbus and Gnd in the outer ones and twisted pair signal in the middle one (hopefully).

author: Harimake
author_rank: Contributor
timestamp: August 11, 2022, 08:48:17 pm
content: Yes, I totally get it. This isn't even used for USB protocol. I believe they are using some very slow serial protocol and just using USB connectors for convenience... Length wasn't an issue in the original implementation.

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2022, 08:55:29 pm
content: (I added a P.S. above, probably not relevant now - although twisted Rx and Tx wouldnotbe good!).Personally I would avoid re-using USB connectors for non-USB applications, that way lies misery! I would go for RJ11 connetors, You ought to be able to source those pre-terminated much easier... or even crimp them yourself.

author: Harimake
author_rank: Contributor
timestamp: August 11, 2022, 08:59:18 pm
content: Oh, if only I had control over this... This thing goes into equipment with USB ports beings used for non-USB data transfer.