Author Topic: Garmin 705 Extending Battery life  (Read 14496 times)

Garmin 705 Extending Battery life
« on: 22 March, 2009, 07:29:41 pm »
I've had great results from my 705 on 200k Audax rides and now want to use it for a 300 - but fear the battery, at 12-15 hours, just won't go the distance.

I was thinking of getting one of these - Garmin Edge 305 Portable AA Battery Charger uses TipExchange and have two questions:

- has anyone used one on the road with a 705?
- I hear that some people find that when they put their 705 on charge away from the mains charger, the unit thinks it is linked to a computer and won't work as it should (which would rather limit a recharger's usefulness when rolling along...) - Any wisdom out there????

Liam

Jaded

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Re: Garmin 705 Extending Battery life
« Reply #1 on: 22 March, 2009, 07:37:37 pm »
OK - I bought one of these and I've not had to use it in anger yet, like you I've found that the battery is fine for a (slow) 200km.

However, they send you one with the batteries side by side. It is quite flimsy and more importantly, you cannot get rechargeables into it and close the lid. I brought this up with them and they sent me a replacement, which has the batteries arranged in two side by side lengthways pairs. It is much better built too.

My plan would be to run the Garmin off the batteries to stat with, then go to the internal battery afterwards. Or carry more AA rechargeables with me.
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #2 on: 22 March, 2009, 07:48:48 pm »
I bought a battery pack called Lil Sync for my 205 and it does work with my 605. You're right about the 605/705 thinking it's connected to a PC so you have to get a power only USB cable. I had a selection and tried them all and found one that supplied power but didn't send the 605 into PC mode. The USB cable from a Free Loader, solar power pack, also does power only. Check them out as they may sell the cable separately.

Jaded

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Re: Garmin 705 Extending Battery life
« Reply #3 on: 22 March, 2009, 08:21:28 pm »
Just to add, when you plug this adaptor in the Garmin lights up, so I have to turn the back light off again. It behaves as an external power source. The plug for it projects quite a way out the back of the unit, at least as much as the computer USB plug. So, if you can't get your computer lead plugged in when the 705 is mounted on the bike, you'll have to change the mount to be able to use this battery pack.

You can get other TipExchange converters, I have one for the iPod/iPhone too, so the battery pack will get me out of a problem with a flat phone too.
It is simpler than it looks.

yello

Re: Garmin 705 Extending Battery life
« Reply #4 on: 23 March, 2009, 09:32:54 am »
However, they send you one with the batteries side by side. It is quite flimsy and more importantly, you cannot get rechargeables into it and close the lid. I brought this up with them and they sent me a replacement, which has the batteries arranged in two side by side lengthways pairs. It is much better built too.

I found this too but just assumed that that was they way they were built and thought no more of it. So good on yer Jaded for being pro-active!  :thumbsup: I just use mine with std alkalines... and rubber bands to keep it together!

Jaded

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Re: Garmin 705 Extending Battery life
« Reply #5 on: 24 March, 2009, 12:07:37 am »
Here's the Garmin mounted, and the battery connector shown




This is the 'new' battery holder, resting on the top tube for the photo



Finally the 'old' battery holder, clearly showing that I can't shut the rechargeables in!


It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #6 on: 24 March, 2009, 12:19:54 am »
I have the Gomadic one you have linked to. (In a 305) it works fine as an external power source (light does not come on when connected but battery meter shows that device is charging).

However, it is not able to accommodate Ansmann re-chargeables. Also, the battery springs are very weak.


Jaded

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Re: Garmin 705 Extending Battery life
« Reply #7 on: 24 March, 2009, 09:43:25 am »
The other one os a Gomadic too, they just don't seem to advertise it. I guess the margin on it is way less, as it is much better built. Also a better shape for fixing to a tube etc.
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #8 on: 24 March, 2009, 10:12:13 am »
Thanks guys

I have bought the 4 battery Gomdaic but now feel that the dinky version looks much neater!!!! 

Hope it's waterproof as it look like its going to be soggy on Saturday

L

Jaded

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Re: Garmin 705 Extending Battery life
« Reply #9 on: 24 March, 2009, 10:20:45 am »
Liam, they are both 4 battery.
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #10 on: 24 March, 2009, 10:31:50 am »
... and do you run it all day or just dig it out when the internal battery on the Garmin is getting low?

Liam

vorsprung

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Re: Garmin 705 Extending Battery life
« Reply #11 on: 24 March, 2009, 10:38:01 am »
hmm I know I am not an electronic genius but

1) There is a cheap and reliable DC-DC 5v regulator called a 7805.  In various flavours but the one I have in mind does up to an amp
2) USB spec calls for "5 +/- 0.25 volts" and up to 500ma
3) A schmidt hub will do up to 500ma.  And it isn't busy in the day
5) USB sockets are widely available as salvage on last years equipment




Jaded

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  • Formerly known as Jaded
Re: Garmin 705 Extending Battery life
« Reply #12 on: 24 March, 2009, 10:39:48 am »
... and do you run it all day or just dig it out when the internal battery on the Garmin is getting low?

Liam

Oh, I'm on the steep learning acent at the moment. (The one that the altimeter can't assess properly!  ;D)
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #13 on: 24 March, 2009, 10:42:42 am »
... and do you run it all day or just dig it out when the internal battery on the Garmin is getting low?
Sorry to jump in here.
I've had my 605 going for 12.5 hours and there were still a couple of bar indicators to go. Mostly I use my battery pack to recharge when I'm camping. I have used the battery pack, with my 205, to run/charge as I was riding and once with the 605 when I thought it might run out of internal power 20 miles from home.

Re: Garmin 705 Extending Battery life
« Reply #14 on: 24 March, 2009, 10:45:31 am »
1) There is a cheap and reliable DC-DC 5v regulator called a 7805.  In various flavours but the one I have in mind does up to an amp
2) USB spec calls for "5 +/- 0.25 volts" and up to 500ma
3) A schmidt hub will do up to 500ma.  And it isn't busy in the day
5) USB sockets are widely available as salvage on last years equipment
Already available hub powered chargers, mostly German origin.

Re: Garmin 705 Extending Battery life
« Reply #15 on: 24 March, 2009, 10:47:25 am »
The solution is to keep lobbying Garmin to produce a version of the Edge series which takes AA batteries.

I can get 60 hours out of my eTrex with a pair of Lithium AAs in it. 40 hours or so with a pair of 2700mAh rechargeables.

The reason I haven't bought an Edge is simply because of the non replaceable batteries, if they had that it'd be the perfect cycling GPS.
"Yes please" said Squirrel "biscuits are our favourite things."

Re: Garmin 705 Extending Battery life
« Reply #16 on: 24 March, 2009, 10:54:08 am »
The reason I haven't bought an Edge is simply because of the non replaceable batteries, if they had that it'd be the perfect cycling GPS.
I think it is perfect, or at least very close, for cycling. The cycling that I do anyway.   ;)
Do you want a GPS for cycling or audaxing? If I audaxed then I think I would find the lack of battery changing a drawback.

Re: Garmin 705 Extending Battery life
« Reply #17 on: 24 March, 2009, 11:05:49 am »
I think it is perfect, or at least very close, for cycling. The cycling that I do anyway.   ;)
Do you want a GPS for cycling or audaxing? If I audaxed then I think I would find the lack of battery changing a drawback.

Exactly. I want it for Audaxing which is a pretty niche market. Since I don't rely on mapping (only preplanned routes) then the 605/705 are over the top for my needs, a 305 that takes AA batteries is what I need, but a 605/705 without purchased maps (or just importing OSM) would be nice for the colour display.
"Yes please" said Squirrel "biscuits are our favourite things."

Jaded

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  • Formerly known as Jaded
Re: Garmin 705 Extending Battery life
« Reply #18 on: 25 March, 2009, 11:27:13 am »
An update on the battery pack situation.

I've just got a (very expensive and very rare) USB mini extension cable. The means I can put the battery pack in my rack bag and run the cable to the GPS. It also means that the plug is no longer fouled by the (bar) stem. I was worried that this would eventually result in failure of the USB mini socket on the GPS.

(edited for rubbish  ;D)
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #19 on: 25 March, 2009, 11:38:06 am »
The alternative could have been a tri-bag mounted just behind the stem although I'm not 100% sure that the battery pack would fit in it (I have a similar one I use as an emergency phone charger or to put a bit of charge in my Garmin Forerunner as it only lasts 8 hours, will check whether it fits later on). Still might not be ideal as it may put too much force on the cable where it exits the box and cause it to break.

Like this one:

Tri Bag All Weather - Bikes & Cycles Online - Tredz.co.uk
"Yes please" said Squirrel "biscuits are our favourite things."

Jaded

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  • Formerly known as Jaded
Re: Garmin 705 Extending Battery life
« Reply #20 on: 25 March, 2009, 11:42:09 am »
Ah. I put my route sheet there!
It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #21 on: 25 March, 2009, 11:43:39 am »
I think the problem with the Tri Bag is cable length.

Size-wise the bag is about 20 mm longer than 2 AAs placed end to end so either version of the Gomadic would fit.

Re: Garmin 705 Extending Battery life
« Reply #22 on: 25 March, 2009, 12:32:21 pm »
Ah ha - the obvious thing I didn't check!  Looking at the photo in a previous posting it looks as if the cable from the pack is only 15cm... which, unextended, would make anything but taping to the headset difficult.  Am I right?

L

Jaded

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  • Formerly known as Jaded
Re: Garmin 705 Extending Battery life
« Reply #23 on: 25 March, 2009, 12:35:56 pm »
Flexible portion of cable from the 4 wide pack is 16cm
Flexible portion of cable from the 2 side by side pack is 14cm


It is simpler than it looks.

Re: Garmin 705 Extending Battery life
« Reply #24 on: 25 March, 2009, 01:08:02 pm »
Thanks... now, what other pointless tasks can I set you?

Liam