I put my Active 10 onto a phone charger. It did not overheat of blow up, so I tried the same with the Active 12. No short term problems.
Maybe the battery will not last as long but I do no see any reason why not.
I will use the Satmap charger at hone and my phone charge on holiday which will save me abt 8 oz in my pack

I have also bought a USB Sonic toothbrush from Boots which is very light!

I have spoken to SATMAP technical help. The reason companies tell you to only use their specific charger is because they know that some people might otherwise use an unsuitable one. If the advice in the previous post is followed correctly there is no problem in swapping chargers about. Just take care!

I am still being cautious and I will experiment on my old Active 10 when I get back from Pembrokeshire next week.

John
Thanks for the feedback
I contacted GPS training with my question and they say:

"It is fine to use an alternative charger if it is of the same output rating as the Satmap charger (5V, 0.6A)

In short, when replacing an external power supply or charger:
Make sure that the voltage matches.
Make sure that the new supply is rated to provide the same amperage or more.
Make sure that the connectors match, both in physical form and in polarity"

ENDS

Now this accords with my knowledge of physics and it must be right. But I am still hoping to hear from someone who has tried this before I try it myself!

My Satmap 12 has now been returned from Satmap following the repair to the broken joystick. And I must say that it's a completely different beast! They appear to have replaced many other components in addition to the joystick. The joystick is now a joy-to-use; I now realise that the old joystick hadn't worked properly from day one. Previously 'sticky' buttons now operate freely. The return note says Components Repaired: "Front Clam, Inner Screen Cover, USB Rubber Seal, Joystick Extender, Main Frame Seal, Software Upgrade".
There's also a test results table:
Time to First Lock1 00:01:24 Time to First Lock 2 00:01:13 Time to First Lock3 00:01:11
Max Signal to Noise Ratio 44 Average Signal to Noise Ratio 40

As mentioned earlier, I intended testing to see whether the S12 can be fully turned off after plugging into the charger (not just turning the screen off). I have now performed this test & I can confirm that the S12 can be fully turned off once connected to the charger and that the battery does fully charge. Test this for youselves though as I wouldn't want to be responsible for your non-charged devices. This looks like the end for accidental battery run-down following disconnection from the charger.
I had never been able to reset the unit from the 'frozen' state except by removing the battery. However, some notes from Raymond Wilkes (thanks Ray) hinted at a solution to this. I had previously tried to reset the 'frozen' unit by pressing the power switch, but with out success. Ray's notes said that this switch could reset the unit (but without saying how long to press it for). Realising that the S12 is of course a computer, I tried the 10 second power reset approach; a 'hung' or 'frozen' PC or computer can be powered off by holding the power button for between 5 to 10 seconds. The next time that the S12 'froze', I held the power button for 10 seconds and low & behold, it reset itself. If it 'freezes' again, I'll try this approach again.

Another test that I will perform will be temperature resilience. In the past few months, my S12 has 'frozen' on several occasions. Each time the external temperature was just below freezing & I was wearing the unit outside my clothing around my neck. On one similar day I carried the unit inside my rucksac & it didn't 'freeze' on that occasion. I have the waterproof rubber casing, so I'll put it in the fridge and see what happens. Satmap claim that it will work down to minus 10deg C so I'll see what happens.

Thank for this John - it had also occurred to me and Battery Univ also say its OK
But I suspect SATMAP are being overcautious. It is also awkward that the battery can only be charge in the Active 12, not convenient for topping up a spare as swapping is so fiddly. But I would not like a touchscreen GPS so I will have to put up with these various problems.

Ray, thinking about your intention to only use one USB charger for your three devices, it occurs to me that your safest option would be to use the Satmap charger for this purpose. My thinking is that it would present no incompatibility risk with the S12 (obviously) and would appear to present less incompatibility risk with your two phones (I've charged my phone from many different chargers). Whereas using a phone charger might present a much higher risk if used with the S12, especially as that has a much larger battery with attendant higher explosive & fire power.

I always turn mine off after charging has stated and it is always ok the next morning, ok insofar as it works all the next day. Yes it is very annoying that there is no 'full' indicator
On the original topic I got back to Battery university quoting Satmap's warning from the manual
they said:
"Recommending (strongly in this case) to only use OEM chargers is very common and makes sense. As a manufacturer you have no control over other chargers and need to safeguard your customers equipment".
Which contradicts what they said earlier!
t is entirely possible that Satmap's warning is right, but also possible they are just playing ultra safe. Which is what I will do unless I find out its not necessary
So I will do some more digging and report back if I find anything useful. I was hoping some adventurous LDWA member had tried it and found out if it was OK or not.
One cycling usergp member had found 8v will blow up a 5v item, no surprise there. And they recommended not using a charger from a £1 shop. Well you wouldn't.

Louise, yes, I too have a Satmap 12 (S12). I am aware that it does turn itself on when plugged into the charger. I always then turn the screen off and then wait for hours & hours while it charges. My next experiment will be to actually turn it off again once charging starts in order to see if will actually complete its charge cycle when turned off. Unfortunately I can't do this at the moment as my unit's away with Satmap having its broken joystick repaired. Ho Hum.
Battery life management with the S12 has always been problematic. I'm never sure how long to leave it plugged into the charger. I feel that it's a design shortcoming that neither the charger nor S12 give a visual indication that charging is complete; it's always hit or miss. I'm not sure if it's the charger or the S12 that determines when the battery is fully charged and switches off the current. Almost all other chargeable electronic devices that I possess have some sort of indicator (red light, green light, light off etc) to show when charging is complete. I find it annoying that the S12 doesn't do the same.
When it works, I find the S12 to be a good device, but it has so many quirks & idiosyncrasies that I'm repeatedly annoyed by it.

Question/comment for John Penifold/in relation to the post on 4th March - indicating that devices should be switched off when charging. Just wanted to highlight that the Satmap automatically switches on when it starts charging [and you have to remember to switch it off after charging]. It is actually impossible to charge it without it switching on.

John
You are absolutely right I was hoping someone with expert knowledge would say it was OK!

I emailed the recommended Battery University after going through the articles and not knowing what to conclude.
I put:

I would like to know if I can use a standard phone charger 5v 2A on any device which has a 5v input. I have several gadgets and phones which are 5V and either 1 or 2 A input. On hiking trips I could carry 8 ounces less if I could use one charger! They are all less than 3 year sold and I think they are all Lithium batteries
I have read some your articles but not sure what it all means

They said

"If we are talking USB, then yes you can interchange USB powered devices with an "USB" charger. USB is a "Standard" and this will work for the majority of "USB" devices".

So I think I will chance it now, but thanks for the link which got me on the trail

What do you think now? - the stuff in the articles certainly put me off, but then there was the simple e-mail reply!

John, thanks for bringing this up.

Looking at my AAA rechargeable battery collection as used in the head torch, they're all Ni-MH, but of different makes. With older cameras, I have previously recharged different makes of alkaline AAs, before that rechargeable lead-acid AAs. I take the point regarding safety and will take more care not to leave them (the AAAs) unattended when on charge (and more care as to where I leave them). One of my chargers does indicate when charged, the other not, so I'll stop using that one.

I don't know what type of batteries are used in most makes of GPS-enabled devices, phones, iPods and tablets (or e-cigarettes). If they're Lithium or Li-on, I'd draw people's attention to the following.

Iain.

++++++++++++++++

Extracts from batteryspace.com:

IMPORTANT SAFETY INSTRUCTIONS AND WARNINGS For LI-ION/POLYMER BATTERIES

* Lithium Polymer and Li-ion batteries are volatile. Failure to read and follow the below instructions may result in fire, personal injury and damage to property if charged or used improperly.

* Li-Ion and Polymer battery & packs may explode and cause fire if misuse or defective.

* Use specific Lithium Polymer/Li-ion charger only. Do not use a NiMH or NiCd charger- Failure to do so may a cause fire

* Never charge batteries unattended. When charging LiPo/Li-ion batteries you should always remain in constant observation to monitor the charging process

* Batteries that lose 20% of their capacity must be removed from service and disposed of properly.


IMPORTANT SAFETY INSTRUCTIONS AND WARNINGS For NIMH BATTERIES

* Please always use a smart charger (with automatic power cut-off function) [for] charging NiMH battery. Charging [an] NiMH battery without attention [so it becomes overcharged] may cause [the] battery [to] explode.

* When charging NiMH battery, please always put the battery in a wire-proof place to avoid any accident happen[ing]

* Suggest you change NiMH batteries and packs at least every six months, otherwise NiMH battery will reduce capacity or [become] dead.

Ray, I'm getting the impression that despite all the information that I've provided (technical stuff & safety stuff), you're still hoping that somebody is going to say "Go ahead Ray, what you want to do is perfectly safe".
All I can say is that in article after article, the common warning coming through is "Make sure when you're buying batteries and chargers to match them up". This is what Satmap have already done for us, so question them about it.

Thanks for the responses
Given that these batteries can explode or catch fire if misused, then safety is paramount.
They are also expensive so I would not want to damage them or shorten their lives
But all my chargers say the output is 5V, the only difference is that the current varies
One charger instruction said if you overloaded the batteries would take longer to charge, not that any harm would come.

Hopefully another LDWA member who has tried it put will get back!

Iain, unless you were a complete expert and knew all the technical specifications of all the components involved, you wouldn't be able to tell whether a particular combination was a safety issue or an inefficiency issue. Always better to err on the side of caution.
I have personally seen the effects of using the wrong charger on an e-cigarette (not mine I add); a hotel fire was narrowly avoided by their new fire detection system. See my photos here: https://www.flickr.com/photos/john_pp/albums/72157641398599034.
Here's a video of a Lion battery overcharge: https://www.youtube.com/watch?v=ixIOEPnsgbI.
I'm not familiar with rechargeable AA and AAA lead-acid batteries. Do you mean NiMH (Nickel Metal Hydride) or NiCd (Nickel Cadium)?
The original question wasn't about battery performance but battery safety.

It's not clear (to me) whether the technical description of charger incompatibilities means that attempting to use other charger(s) is unwise on grounds of safety (overheating, significant damage to battery or device components ?) or merely inefficiency (completeness of charge, charge time, charge leakage ?). If the latter, there might be a trade-off between convenience and acceptable battery performance over shorter periods such as single days.

The manufacturers of rechargeable AA and AAA lead-acid batteries typically insist that different makes should not be combined together when under charge. Other than leaving them on charge for too long (not all chargers indicate when ready), this does not seem to create problems. I've tried charging singly, in combination and with other types (both makes and sizes), without noticeably different results.

For GPS-enabled hand-held devices, battery performance may depend more on whether or not GPS 'roaming' can be, or is automatically, switched off when not in use than it does on the charger which is used.

That same article also explains why it's important to turn off the Satmap (or any other type of portable device) while being charged.
Here's the extract to save you having to scan the whole article:

"A portable device should be turned off during charge. This allows the battery to reach the set voltage threshold and current saturation point unhindered. A parasitic load confuses the charger by depressing the battery voltage and preventing the current in the saturation stage to drop low enough by drawing a leakage current. A battery may be fully charged, but the prevailing conditions will prompt a continued charge, causing stress."

Here's the extract about non-compatibility of charger types:

"While the traditional lithium-ion has a nominal cell voltage of 3.60V, Li-phosphate (LiFePO) makes an exception with a nominal cell voltage of 3.20V and charging to 3.65V. Relatively new is the Li-titanate (LTO) with a nominal cell voltage of 2.40V and charging to 2.85V. (See BU-205: Types of Lithium-ion.)

Chargers for these non-cobalt-based Li-ions are not compatible with regular 3.60-volt Li-ion. Provision must be made to identify the systems and provide the correct voltage charging. A 3.60-volt lithium battery in a charger designed for Li-phosphate would not receive sufficient charge; a Li-phosphate in a regular charger would cause overcharge."

Ray,
I have been researching this (with great difficulty, not knowning the correct key words to use) and have finally found an authoritative source.
It would appear that you should NOT use a different charger, especially on the Satmap LiPol batteries.
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

When I go on a trip I do not want to take 3 chargers, one for my Satmap, on for my phone and another for my wife's phone.
But each device is insistent that you should only use the supplied charger and no other.
I do not see why this should be the case.
Has anyone used a standard phone charger for a Satmap?