Garmin Etrex30 - external power source cable issue

[John Stonebridge]

Hi there

I've used a Garmin Etrex30 for donkeys years.  Its not the swankiest I know but its got long battery life and I'm quite happy to follow a line rather than have all the bells and whistles.  I also like the fact that its not touchscreen.   

However, with deteriorating eyesight I have recently started using an external power source as I need the backlight on full 100% of the time in order to make out the detail on the screen (I assume this would be a big battery drain with regular 2 * AAs - and I do tend to ride audax distances). 

I use a pebble explorer which sits in a small top tube bag with a standard USB - Micro USB cable.  I noticed on a ride yesterday however that the cable has a tendency to work loose from the GPS unit end which then triggers an on screen prompt me to keep using it with batteries or to switch off. 

I had a look at the unit this morning and Im struggling to see what I could do to make the connection more snug

My only idea so far is to look to secure the USB cable to a brake / gear cable at the point nearest the GPS unit to keep the USB - Micro USB cable up, but I suspect that may only make a marginal difference.  There's no obvious way of providing a clamping effect without obscuring the screen which rather defeats the purpose.

Of course the Etrex30 has the micro USB port on the underside which strikes me as a poor design, once a few potholes + gravity have taken their toll. 
 
Any ideas?     

[JonB]

I switched from an Etrex a few years ago but I never found the backlight to be a significant drain on the battery, although I only had it on the lowest illumination setting. I never bothered with trying to power it from an external source, I just carried spare AAs, most of the time I'd just take 2 but obviously this varied on the length of ride. I used to use the Eneloop rechargable batteries which would easily do a 200.

[JonBuoy]

Wot Jon sez but...

I had this problem on my Garmin 705 and used a low tech solution involving an elastic band.



I have just dug out the cable that I used and it looks like it should work OK on my Etrex 30X.  It covers one of the zoom buttons but it is still usable.



I assume that one of the advantages of having the USB on the bottom is that the unit is less likely to fill up with water when it rains.

NB I have heard about people damaging the USB with all of the jiggling.

[Kim]

I switched from an Etrex a few years ago but I never found the backlight to be a significant drain on the battery, although I only had it on the lowest illumination setting.

I measured it at one point.  I've forgotten the numbers, but it was something like an extra 30% with the backlight on full, and an extra not-a-lot with it on minimum.  Where it really makes a difference is when the battery is nearly depleted, as you can eke out a bit more capacity if you keep the current lower.


The problem with the eTrex is that the mini-USB connector was designed for infrequent desktop use like downloading photos from digital cameras or uploading routes to GPS receivers, and wasn't built to withstand the number of mating cycles that micro-B and USB-C (which appeared after USB charging became more common) were.  The later connectors put the springy part in the plug, so when it wears out you only have to replace a cable, whereas with mini it's in the socket, so when that becomes intermittent it's a real pain.

TBH, I'd avoid using any USB connector on a moving bike if I had the choice.  The great thing about the eTrex, compared to the Edge series, is that removable standard batteries mean you don't have to.

[John Stonebridge]

Thanks all.  I'll give the low-tech elastic band approach a try (my other half recently arrived home with a huge bag of them following an office tidy up as they were being thrown out so thats a  )

If all else fails I'll ditch the external power source and just monitor how quickly I gallop through AA batteries. 

[Cudzoziemiec]

Addressing another point, tangentially relevant, it might not just be your failing eyesight that means you need the backlight on more. I reckon the screen itself darkens with age. Of course my eyes are also older than they were when I bought my Etrex 20, but they're not so bad yet.

[Feanor]

Over the years, I've killed Edge 800s on 3 occasions doing this.
Once by mechanical damage, and twice by drowning.
I was able to repair them, but it's not particularly easy.
So it's not a great thing to do, if you can avoid it.

Newer Garmins have external pogo-pin connectors like a camera flashgun hotshoe, and can connect to external power this way.

[Kim]

Newer Garmins have external pogo-pin connectors like a camera flashgun hotshoe, and can connect to external power this way.

The early eTrexen used something similar for their serial/power connection.  I had an aftermarket cable that would have worked a lot better on a bike than any of the USB connectors.  Mini-B seemed like such a retrograde step.

[Feanor]

My running watch ( a Suunto ) has a linear row of pads, and the cable has a matching row of pins, and a massively strong magnet.
You more-or-less wave the cable in the general direction of the watch, and it clamps on like a small dog humping your leg.

[aidan.f]

ninety degree cables are a 'thing' you can get them in left, right, up and  down