A thread about robust USB cables for touring

[Polar Bear]

Take two:  ( My original attempt to raise this thread failed  )

I have a device to convert my SON output to standard USB.   I'd like a quality bit of cable to connect either my Garmin or my Portapow (mini usb) or my htc Desire HD (micro usb).   I can also carry a usb wall wart allowing me to charge devices from mains where available so short leads are not necessarily ideal.

Thoughts and recommendations please?

... a thread about sensible USB cables for touring would be interesting...  I've just invested in some nice Startech ones with short lengths and right-angular connectors for the purpose.  I'm not sure USB connectors (especially the micro ones) really come in 'robust' though.

[Feline]

Take two:  ( My original attempt to raise this thread failed   )

I have a device to convert my SON output to standard USB.   I'd like a quality bit of cable to connect either my Garmin or my Portapow (mini usb) or my htc Desire HD (micro usb).   I can also carry a usb wall wart allowing me to charge devices from mains where available so short leads are not necessarily ideal.

Thoughts and recommendations please?

... a thread about sensible USB cables for touring would be interesting...  I've just invested in some nice Startech ones with short lengths and right-angular connectors for the purpose.  I'm not sure USB connectors (especially the micro ones) really come in 'robust' though.

If you are only using a USB cable for charging and not to connect to a PC then it only needs the black and red power wires inside to be connected and not the data ones (green and white). It is therefore relatively easy to shorten any USB cable you like by soldering the red and black wires back together and then tape up the join with self amalgamating tape. I have one of these I made myself to connect my Garmin to Dahon Reecharge while both are on the bike. It is pretty robust. I used a bog standard Garmin cable to make this out of.

I should probably add that it is necessary to alter the cable if you want to use a Garmin 705 while you charge it because the data cables send it into PC mode which means you can't use it. If you leave the green and white data cables disconnected inside the shortened cable then it works fine

[TimO]

If you want the cable to be as robust as possible, you're probably better off getting cables as close to the dimensions that you want, and not shortening them.  If you shorten a cable, you'll introduce small nicks in the wire, and hard solder points, both of which will encourage breakages (we use thermal strippers at work to avoid this sort of problem on spacecraft cabling).

As Kim says, I'm not sure that any USB connectors really come in rugged, and since the places you plug them into won't be particularly ruggedised either, it probably wouldn't be a vast help anyway.

[Biggsy]

In what way is an average cheapo USB cable not robust enough for touring?

The only problem I can think of it water ingress at the connections - but that's a problem for the devices - perhaps helped with some self amalgamating rubber tape or heat shrink tubing.

[Polar Bear]

I have found that the plug ends on cheapo cables have a tendency to fall apart at the most inopportune of moments.

[TimO]

I have found that the plug ends on cheapo cables have a tendency to fall apart at the most inopportune of moments.

I've yet to have any USB connector fail (full sized, mini or micro), although they don't tend to get used as heavily as things like power jacks, which I have had fail from time to time (although normally it's fracturing of the cable just behind the connector, not the connector per se).

[Feline]

I think I would be tempted just to pack a spare, since they are not heavy or bulky.
I have noticed that the cable that came with my Garmin is more robust than an identical cable I have that came with my digital camera and one I just randomly bought as a spare. I suppose this reflects the type of use of the 2 gadgets one being fragile and one a chunky waterproof sat nav.

[Polar Bear]

I've yet to have any USB connector fail ...

Unfortunately I have.   I seek robustness and reliability.

I have noticed that the cable that came with my Garmin is more robust than an identical cable I have that came with my digital camera and one I just randomly bought as a spare. I suppose this reflects the type of use of the 2 gadgets one being fragile and one a chunky waterproof sat nav.

Which indicates that there are differing qualities of cable.   I was hoping this would be the case.   Now I need to find where the heavier duty jobbies can be obtained from   

[Feline]

I think you need to go for ones like these with rubberised mouldings where the connectors join the cable for strength


Philips - USB 2.0 cable A/5-Pin mini B connectors 3 m Black - SWU2173/10 - PC cables and adapters (USB) - Cables and connectors - Accessories

[Kim]

If you are only using a USB cable for charging and not to connect to a PC then it only needs the black and red power wires inside to be connected and not the data ones (green and white).

Only partially true:

The USB charging standard makes use of the data lines to identify a device as a 'dumb charger'.  Such a device (typically a wall-wart, but also battery packs and the like) will join the data lines together through a token low-value resistor (IIRC the spec says 120ohm).

A power-hungry device like a phone can then tell it's connected to a charger with more than the USB standard 500mA current limit available and can charge at a decent rate.  This avoids the need for a microcontroller to act as a USB host and do the full power level negotiation, as would happen when plugged into a computer.

Typically, a device following the spec will refuse to charge or only charge at a very low current if connected to a power source with the data lines left floating.  Of course, not all devices follow the spec - some are cheap and nasty and make assumptions, and some don't pull enough current to have to bother.

Apple, in their infinite capacity for evil, have their own variation of the standard, where they put specific voltages on the data lines to identify an Apple charger.  Hence various iProducts may be extra-fussy about what they charge from.


Oh, and FWIW: the colours in a USB cable *are* standardised as Feline says, but I have come across (cheap, nasty) cables with non-standard colours.

[Feline]

My Garmin Edge is unusable whilst charging with a cable with intact data cables in it. That's why I had to demolish and fettle a cable for it. I actually connected the data cables together inside it at the device end and left them unconnected at the USB end.

[Kim]

I have found that the plug ends on cheapo cables have a tendency to fall apart at the most inopportune of moments.

I've yet to have any USB connector fail (full sized, mini or micro), although they don't tend to get used as heavily as things like power jacks, which I have had fail from time to time (although normally it's fracturing of the cable just behind the connector, not the connector per se).

The usual failure modes I've seen for USB connectors are wiggle-related solder death at the device end, and plugs being crushed out of shape by shoes or wheely office chairs.  The former is 'game over' in a touring context, the latter doesn't seem particularly likely.  I've yet to have a plug come apart on me - they're usually fairly solid moulded things - I'd expect the cable to fail first.

Right-angle (or indeed left-angle, it seems you can get both kinds) plugs are an obvious way of reducing cable bend radius issues in some circumstances - I've just invested in some for my phone, mainly so it will sit on my desk at a sensible angle, but also to reduce sticky-outyness if I have it connected to a charger in a bag.

At the end of the day, anything's better than those tiny Nokia DC plugs  

[Kim]

My Garmin Edge is unusable whilst charging with a cable with intact data cables in it. That's why I had to demolish and fettle a cable for it. I actually connected the data cables together inside it at the device end and left them unconnected at the USB end.

Fair point.  Note you're effectively following the dumb charging standard there, which makes me wonder what the Reecharge is doing differently.  Maybe they actually put a USB host in it to allow devices to follow power availability.  That would be a bit clever...

[Feline]

My TomTom in the car has a right angled bend in it's cable (incidentally this is mini USB just like the Garmin) but I trod on it in the car foot well one day and bent it so it no longer works. Fortunately the cable from my old in car Garmin fitted so I use that one now.
It is actually quite handy that if I have driven to an Audax I can plug the Garmin Edge in to the TomTom car cable to make it save the course, turn itself off and charge itself back up. It seems to me this is a good way of getting your data nicely stored at the end of a ride, and in theory you could then start a new data file if you did another ride.

[Valiant]

Make your own and use armoured cable? Shouldn't cost any more than £10-15. You can also get lock plugs, someone like Neutrick will do them.

[Kim]

While I'm a big fan of indestructable Neutrik connectors (I still lack an excuse for using an Ethercon for anything), they're not much use when you have an existing gadget that won't mate with them.

(I've just looked, and they do a similar USB-inna-XLR-alike-shell series, but unsurprisingly, only in the full-size A and B connectors.)