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KX3 interal battery charger

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K7TV

KX3 interal battery charger

JP wrote: All battery packs, regardless of chemistry, benefit from a
periodic balance/equalize charge.

Do you have any specific recommendation on how often one needs to take out
the NiMH batteries to balance them?

The KX3 battery holders are very solid (good) but I find it difficult to
remove the batteries, as significant force is needed. I have a set of NiMH
in there, and my default plan is to just leave them there for as long as
possible. I hope I can install the charger when it arrives without removing
the batteries. And, I am running on external power whenever I can, so that
the internal batteries won't need to be charged until the internal charger
arrives.

73,

Erik K7TV

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JP O'Connor

Re: KX3 interal battery charger

Hi Erik,

I do not have enough personal experience with these to provide a
suggested guideline based on my own empirical results. Other readers of
this thread may have that knowledge or know of references.

I suspect that if one does not abuse their cells, and if the cells are all
in good shape to begin with, that removing the cells every few months
should suffice.

When I install my KXBC3 I will test and charge a set of AA cells so I have
a baseline set of stats on the cells. Then I will check them after a few
cycles of use and test/charge to see how well they stayed balanced. If
badly out of balance at that point, then frequent balancing (or selection
of a few different cells for better matching) may be needed. I suspect they
will work very well, however, with balancing needed only every few months -
subject to how often they are charged and discharged.

Sorry that I could not be of more help on this. Possibly others can weigh
in for us.

Thanks,
JP

72/73 de WF4Z

On Mon, Jul 2, 2012 at 11:49 PM, Erik Basilier <[hidden email]> wrote:

> JP wrote: All battery packs, regardless of chemistry, benefit from a
> periodic balance/equalize charge.
>
>
>
> Do you have any specific recommendation on how often one needs to take out
> the NiMH batteries to balance them?
>
> The KX3 battery holders are very solid (good) but I find it difficult to
> remove the batteries, as significant force is needed. I have a set of NiMH
> in there, and my default plan is to just leave them there for as long as
> possible. I hope I can install the charger when it arrives without removing
> the batteries. And, I am running on external power whenever I can, so that
> the internal batteries won't need to be charged until the internal charger
> arrives.
>
>
>
> 73,
>
> Erik K7TV
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

N6WN

Re: KX3 interal battery charger

In reply to this post by K7TV

I also found it hard to remove the batteries from the holders.
The 4 slots (2 on each holder) at the end of each holder have retainers.
Either my fingers are starting to age, or these are hard to remove.

Dan
N6WN
---------------------------------
Date: Mon, 2 Jul 2012 20:49:47 -0700
From: "Erik Basilier" <[hidden email]>
Subject: [Elecraft] KX3 interal battery charger
To: <[hidden email]>
Message-ID: <008101cd58ce$e459a580$ad0cf080$@net>
Content-Type: text/plain; charset="us-ascii"

JP wrote: All battery packs, regardless of chemistry, benefit from a
periodic balance/equalize charge.

Do you have any specific recommendation on how often one needs to take out
the NiMH batteries to balance them?

The KX3 battery holders are very solid (good) but I find it difficult to
remove the batteries, as significant force is needed. I have a set of NiMH
in there, and my default plan is to just leave them there for as long as
possible. I hope I can install the charger when it arrives without removing
the batteries. And, I am running on external power whenever I can, so that
the internal batteries won't need to be charged until the internal charger
arrives.

73,

Erik K7TV
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N6WN --- Question everything, even this!

Don Wilhelm-4

Re: KX3 interal battery charger

Dan,

Let me start with a "smart comment" - not all things in life are easy.

The batteries should be hard to remove because of the spring tension -
if it were easy, than the contact pressure would be questionable.

As far as your fingers aging, while that may be true, I don't think that
is a major factor here - it just makes plain sense to have adequate
spring pressure on the battery contacts.

73,
Don W3FPR

On 7/3/2012 9:32 PM, Daniel B. Curtis wrote:

> I also found it hard to remove the batteries from the holders.
> The 4 slots (2 on each holder) at the end of each holder have retainers.
> Either my fingers are starting to age, or these are hard to remove.
>
> Dan
> N6WN
> ---------------------------------
> Date: Mon, 2 Jul 2012 20:49:47 -0700
> From: "Erik Basilier" <[hidden email]>
> Subject: [Elecraft] KX3 interal battery charger
> To: <[hidden email]>
> Message-ID: <008101cd58ce$e459a580$ad0cf080$@net>
> Content-Type: text/plain; charset="us-ascii"
>
> JP wrote: All battery packs, regardless of chemistry, benefit from a
> periodic balance/equalize charge.
>
>
>
> Do you have any specific recommendation on how often one needs to take out
> the NiMH batteries to balance them?
>
> The KX3 battery holders are very solid (good) but I find it difficult to
> remove the batteries, as significant force is needed. I have a set of NiMH
> in there, and my default plan is to just leave them there for as long as
> possible. I hope I can install the charger when it arrives without removing
> the batteries. And, I am running on external power whenever I can, so that
> the internal batteries won't need to be charged until the internal charger
> arrives.
>
>
>
> 73,
>
> Erik K7TV
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

N6WN

Re: KX3 interal battery charger

Thanks Don,
The two batteries inside each holder are easy to take out. The two
batteries on the outside of each holder are more difficult. It is not a
function of the spring tension ... Probably assuming the spring tension is
the same for each battery, it is the shape of the holder.

That said, the fix is to put a silk ribbon under the outside batteries ...
As has been suggested.

Dan
N6WN
On Jul 3, 2012 7:20 PM, "Don Wilhelm" <[hidden email]> wrote:

> Dan,
>
> Let me start with a "smart comment" - not all things in life are easy.
>
> The batteries should be hard to remove because of the spring tension - if
> it were easy, than the contact pressure would be questionable.
>
> As far as your fingers aging, while that may be true, I don't think that
> is a major factor here - it just makes plain sense to have adequate spring
> pressure on the battery contacts.
>
> 73,
> Don W3FPR
>
> On 7/3/2012 9:32 PM, Daniel B. Curtis wrote:
>
>> I also found it hard to remove the batteries from the holders.
>> The 4 slots (2 on each holder) at the end of each holder have retainers.
>> Either my fingers are starting to age, or these are hard to remove.
>>
>> Dan
>> N6WN
>> ------------------------------**---
>> Date: Mon, 2 Jul 2012 20:49:47 -0700
>> From: "Erik Basilier" <[hidden email]>
>> Subject: [Elecraft] KX3 interal battery charger
>> To: <[hidden email]>
>> Message-ID: <008101cd58ce$e459a580$**ad0cf080$@net>
>> Content-Type: text/plain; charset="us-ascii"
>>
>> JP wrote: All battery packs, regardless of chemistry, benefit from a
>> periodic balance/equalize charge.
>>
>>
>>
>> Do you have any specific recommendation on how often one needs to take out
>> the NiMH batteries to balance them?
>>
>> The KX3 battery holders are very solid (good) but I find it difficult to
>> remove the batteries, as significant force is needed. I have a set of NiMH
>> in there, and my default plan is to just leave them there for as long as
>> possible. I hope I can install the charger when it arrives without
>> removing
>> the batteries. And, I am running on external power whenever I can, so that
>> the internal batteries won't need to be charged until the internal charger
>> arrives.
>>
>>
>>
>> 73,
>>
>> Erik K7TV
>> ______________________________**______________________________**__
>> Elecraft mailing list
>> Home: http://mailman.qth.net/**mailman/listinfo/elecraft<http://mailman.qth.net/mailman/listinfo/elecraft>
>> Help: http://mailman.qth.net/mmfaq.**htm<http://mailman.qth.net/mmfaq.htm>
>> Post: mailto:[hidden email].**net <[hidden email]>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>
>

N6WN --- Question everything, even this!

Jim Low man

Re: KX3 interal battery charger

Hopefully someone will find that the batteries don't need to be removed
frequently
for conditioning. I have eight Eneloop 1,900 mAh batteries ready to go.

For the most part, I will probably use an external battery when
operating portable
for any length of time. I just received an 18 Ah battery and have four
7 Ah ones
as well.

72/73 de Jim - AD6CW

On 7/3/2012 7:30 PM, Daniel B. Curtis wrote:

> Thanks Don,
> The two batteries inside each holder are easy to take out. The two
> batteries on the outside of each holder are more difficult. It is not a
> function of the spring tension ... Probably assuming the spring tension is
> the same for each battery, it is the shape of the holder.
>
> That said, the fix is to put a silk ribbon under the outside batteries ...
> As has been suggested.
>
> Dan
> N6WN
>

Greg Troxel

Re: KX3 interal battery charger

In reply to this post by JP O'Connor

(resent because the list rejected PGP-signed mail)

In "balance" vs "equalize", I also hear about equalization charge to 12V
SLA batteries without access to individual cells. PbAcid cells have a
higher charge/discharge marginal ratio as they get full, so a mild
overcharge should tend to cause all cells to be fully charged. NiMH is
almost certainly similar, especially during low-rate overcharge as is
typical, so I'd expect that all cells end up full.

To understand the KXBC3 behavior, it seems that one should use a Maha
C9000 or equivalent to measure/record the capacity ("refresh/analyze")
of all the cells, and then put then in the KX3 and use them for a while,
and then when the KX3 says they are charged pull them and do a discharge
measurement followed by a refresh/analyze. I'll report back later :-)
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JP O'Connor

Re: KX3 interal battery charger

The balance charging operation requires access to each cell and requires a
smart charger that is appropriately programmed for the specific chemistry
and for the balance operation. The idea is to be sure that each cell is
properly and fully charged without overcharging or damaging any of the
other cells in the pack. This is quite common with the all the various
lithium chemistries, and when using NiCd or NiMh smart chargers that charge
each cell independently. Most of the inexpensive consumer NiCd
and/or NiMh chargers do not treat each cell independently. Only the more
expensive models include the test/refresh modes. Although NiCd and NiMh
cells are often overcharged by many slow chargers, apparently that is not
the best practice when performed on a regular basis. Thus, the smart
chargers.

If I am understanding correctly, a PbAcid (e.g. SLA) equalize charge
operation does not have access to each cell and instead is an operation
that uses a carefully controlled "overcharge" function, within the safe
"operating envelope" of the battery, to bring up the lagging cells without
damaging the stronger cells.

It sounds like equalize and balance are two different operations, intended
for different cell chemistry and charging styles.

Starting with a fresh set of Eneloop (white label 1,900 mAh or black XX
label 2,500 mAh) or other brand of "pre-charged" or low self-discharge
(LSD) NiMh batteries that have had at least one test/refresh cycle
performed, the need for removing the batteries from the KX3 for a
test/refresh cycle should be VERY infrequent as long as they are not abused
significantly. As Jim mentioned, hopefully this won't be too often. Who
knows, even with heavy use, maybe the batteries won't need to be removed
for over a year - or two. Yes, Greg, I plan to do things exactly as you
stated: check after a few months, but then pretty much leave them alone in
the radio for a long while as I see how things work out. I will be
interested to hear from folks here on the reflector as experience is gained.

With the traditional non-LSD high capacity NiMh batteries, the need for
test/refresh may be a bit more frequent. For example, the Energizer 2600
mAh (?) AA cells are notorious for extremely rapid self-discharge and may
need a bit more care and feeding.
72/73 de JP WF4Z

On Wed, Jul 4, 2012 at 3:25 PM, Greg Troxel <[hidden email]> wrote:

>
> In "balance" vs "equalize", I also hear about equalization charge to 12V
> SLA batteries without access to individual cells. PbAcid cells have a
> higher charge/discharge marginal ratio as they get full, so a mild
> overcharge should tend to cause all cells to be fully charged. NiMH is
> almost certainly similar, especially during low-rate overcharge as is
> typical, so I'd expect that all cells end up full.
>
> To understand the KXBC3 behavior, it seems that one should use a Maha
> C9000 or equivalent to measure/record the capacity ("refresh/analyze")
> of all the cells, and then put then in the KX3 and use them for a while,
> and then when the KX3 says they are charged pull them and do a discharge
> measurement followed by a refresh/analyze. I'll report back later :-)
>

mzilmer

Re: KX3 interal battery charger

There are other ways to achieve charge parity (balance). One of them is the multi-cell charge controller. An example for LiPo chemistries is the AAT 3663. Datasheet is available at www.analogictech.com. Doesn't help with AA's, but there is probably an equivalent out there for lower voltage single cells.

Looks to me like Greg is correct about the difference between balancing and equalizing. Xantrex / Trace refers only to "equalizing" with their controlled overcharge on solar charge controllers. EQ is used with FLAs to "stir the pot" and disturb sulfation on the Pb plates, and the process basically allows the sulfates to debond from the lead. With FLAs, I run an EQ for two hours about five times a year.

Matt Zilmer, W6NIA
KX3 #6 / FT

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of JP O'Connor
Sent: Thursday, July 05, 2012 8:58 AM
To: Greg Troxel
Cc: [hidden email]
Subject: Re: [Elecraft] KX3 interal battery charger

The balance charging operation requires access to each cell and requires a smart charger that is appropriately programmed for the specific chemistry and for the balance operation. The idea is to be sure that each cell is properly and fully charged without overcharging or damaging any of the other cells in the pack. This is quite common with the all the various lithium chemistries, and when using NiCd or NiMh smart chargers that charge each cell independently. Most of the inexpensive consumer NiCd and/or NiMh chargers do not treat each cell independently. Only the more expensive models include the test/refresh modes. Although NiCd and NiMh cells are often overcharged by many slow chargers, apparently that is not the best practice when performed on a regular basis. Thus, the smart chargers.

If I am understanding correctly, a PbAcid (e.g. SLA) equalize charge operation does not have access to each cell and instead is an operation that uses a carefully controlled "overcharge" function, within the safe "operating envelope" of the battery, to bring up the lagging cells without damaging the stronger cells.

It sounds like equalize and balance are two different operations, intended for different cell chemistry and charging styles.

Starting with a fresh set of Eneloop (white label 1,900 mAh or black XX label 2,500 mAh) or other brand of "pre-charged" or low self-discharge
(LSD) NiMh batteries that have had at least one test/refresh cycle performed, the need for removing the batteries from the KX3 for a test/refresh cycle should be VERY infrequent as long as they are not abused significantly. As Jim mentioned, hopefully this won't be too often. Who knows, even with heavy use, maybe the batteries won't need to be removed for over a year - or two. Yes, Greg, I plan to do things exactly as you
stated: check after a few months, but then pretty much leave them alone in the radio for a long while as I see how things work out. I will be interested to hear from folks here on the reflector as experience is gained.

With the traditional non-LSD high capacity NiMh batteries, the need for test/refresh may be a bit more frequent. For example, the Energizer 2600 mAh (?) AA cells are notorious for extremely rapid self-discharge and may need a bit more care and feeding.
72/73 de JP WF4Z

On Wed, Jul 4, 2012 at 3:25 PM, Greg Troxel <[hidden email]> wrote:

>
> In "balance" vs "equalize", I also hear about equalization charge to
> 12V SLA batteries without access to individual cells. PbAcid cells
> have a higher charge/discharge marginal ratio as they get full, so a
> mild overcharge should tend to cause all cells to be fully charged.
> NiMH is almost certainly similar, especially during low-rate
> overcharge as is typical, so I'd expect that all cells end up full.
>
> To understand the KXBC3 behavior, it seems that one should use a Maha
> C9000 or equivalent to measure/record the capacity ("refresh/analyze")
> of all the cells, and then put then in the KX3 and use them for a
> while, and then when the KX3 says they are charged pull them and do a
> discharge measurement followed by a refresh/analyze. I'll report back
> later :-)
>

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Edward R Cole

Re: KX3 interal battery charger

In reply to this post by K7TV

JP WF4Z wrote:
=snip
If I am understanding correctly, a PbAcid (e.g. SLA) equalize charge
operation does not have access to each cell and instead is an operation
that uses a carefully controlled "overcharge" function, within the safe
"operating envelope" of the battery, to bring up the lagging cells without
damaging the stronger cells.

It sounds like equalize and balance are two different operations, intended
for different cell chemistry and charging styles.
=snip

Yes, the PbAcid battery bank at my former employment used a PS that
had both float and equalize voltage settings (which were set to the
specific brand-model per their specs). Equalize raised charge
voltage about 0.35v from float and was applied across all batteries
as a bank and not each individually.

Purpose of "balance" and "equalize" seems the same though
accomplished differently (make all cells equal in voltage).

Equalize had both voltage setting and charge timer so it would resume
float at conclusion. These are not cheap units! We had one for 12v
and one for 48v (master battery system for our UPS units).

I do not expect to run internal batteries in my KX3 (except on a rare
flight somewhere). Probably just use AA alkaline's. But opening the
KX3 to change batteries is a delicate operation due to the flex and
power wires. I might opt to make a small gel-cell package with a
power connector, instead.

PS: I made a makeshift mounting bracket for my KX3 that attaches to
the 4-40 tapped holes used for the paddles (which I did not
purchase). Simple flat aluminum plate that I bent up 15-degrees to
view the display directly. Plate screws into my wooden radio
shelfs. I cut a 13/16 inch hole in the plate to "port" the speaker.

73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-?
DUBUS Magazine USA Rep [hidden email]
"Kits made by KL7UW" http://www.kl7uw.com/kits.htm
======================================
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stan levandowski

Re: KX3 interal battery charger

In reply to this post by K7TV

Outstanding creativity, Ed! Now I can get my KX3 up off my operating
desk. Another example of how beneficial this list can be! I'm on the
way out to the garage to dust off the brake. However, I am going to
make a couple extra bends so I can mount the KX3 *below* my lowest shelf
but still *off* the desk. Many, many thanks!

Stan WB2LQF

> PS: I made a makeshift mounting bracket for my KX3 that attaches to
> the 4-40 tapped holes used for the paddles (which I did not purchase).
> Simple flat aluminum plate that I bent up 15-degrees to view the
> display directly. Plate screws into my wooden radio shelfs. I cut a
> 13/16 inch hole in the plate to "port" the speaker.
>
______________________________________________________________
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JP O'Connor

Re: KX3 interal battery charger

In reply to this post by Edward R Cole

Thanks for that explanation, Ed. I have limited experience with the lead
acid battery systems, so I wasn't sure.

On those rare occasions when you do use internal batteries, remember the
alkalines limit you to 3W maximum and even then will have limited life.
Based on your anticipated usage plan, that may be enough. Be sure to remove
them right after your trip since they often leak. The Energizer Ultimate
Lithium, though much more expensive, will allow a bit higher output if you
wish, and will last a lot longer. Again, the best choice depends upon the
individual need.

A few folks have talked about the possibility of replacing the AA cell
holders and rigging their own internal battery pack with a higher density
power source. Given the limited space, it will be interesting to see what
creative solutions are found to provide internal power... and if any
provision is or can be made to recharge the pack without opening the radio.
We shall see!

72/73 de JP WF4Z

On Thu, Jul 5, 2012 at 2:37 PM, Edward R. Cole <[hidden email]> wrote:

> JP WF4Z wrote:
> =snip
> If I am understanding correctly, a PbAcid (e.g. SLA) equalize charge
> operation does not have access to each cell and instead is an operation
> that uses a carefully controlled "overcharge" function, within the safe
> "operating envelope" of the battery, to bring up the lagging cells without
> damaging the stronger cells.
>
> It sounds like equalize and balance are two different operations, intended
> for different cell chemistry and charging styles.
> =snip
>
> Yes, the PbAcid battery bank at my former employment used a PS that
> had both float and equalize voltage settings (which were set to the
> specific brand-model per their specs). Equalize raised charge
> voltage about 0.35v from float and was applied across all batteries
> as a bank and not each individually.
>
> Purpose of "balance" and "equalize" seems the same though
> accomplished differently (make all cells equal in voltage).
>
> Equalize had both voltage setting and charge timer so it would resume
> float at conclusion. These are not cheap units! We had one for 12v
> and one for 48v (master battery system for our UPS units).
>
> I do not expect to run internal batteries in my KX3 (except on a rare
> flight somewhere). Probably just use AA alkaline's. But opening the
> KX3 to change batteries is a delicate operation due to the flex and
> power wires. I might opt to make a small gel-cell package with a
> power connector, instead.
>
> PS: I made a makeshift mounting bracket for my KX3 that attaches to
> the 4-40 tapped holes used for the paddles (which I did not
> purchase). Simple flat aluminum plate that I bent up 15-degrees to
> view the display directly. Plate screws into my wooden radio
> shelfs. I cut a 13/16 inch hole in the plate to "port" the speaker.
>
>
>
>
>
>
>
> 73, Ed - KL7UW, WD2XSH/45
> ======================================
> BP40IQ 500 KHz - 10-GHz www.kl7uw.com
> EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-?
> DUBUS Magazine USA Rep [hidden email]
> "Kits made by KL7UW" http://www.kl7uw.com/kits.htm
> ======================================
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

JP O'Connor

Re: KX3 interal battery charger

In reply to this post by mzilmer

Yes, that appears to be an example of the type of charge controller chips
utilized in the types of balancing chargers mentioned earlier in this
thread. For example, the iCharger 106B+ that I use can handle up to 8 cell
packs in balance charge mode for a variety of different chemistries.

On Thu, Jul 5, 2012 at 12:15 PM, Matthew Zilmer <[hidden email]>wrote:

> There are other ways to achieve charge parity (balance). One of them is
> the multi-cell charge controller. An example for LiPo chemistries is the
> AAT 3663. Datasheet is available at www.analogictech.com. Doesn't help
> with AA's, but there is probably an equivalent out there for lower voltage
> single cells.
>
> Looks to me like Greg is correct about the difference between balancing
> and equalizing. Xantrex / Trace refers only to "equalizing" with their
> controlled overcharge on solar charge controllers. EQ is used with FLAs to
> "stir the pot" and disturb sulfation on the Pb plates, and the process
> basically allows the sulfates to debond from the lead. With FLAs, I run an
> EQ for two hours about five times a year.
>
> Matt Zilmer, W6NIA
> KX3 #6 / FT
>
>
> -----Original Message-----
> From: [hidden email] [mailto:
> [hidden email]] On Behalf Of JP O'Connor
> Sent: Thursday, July 05, 2012 8:58 AM
> To: Greg Troxel
> Cc: [hidden email]
> Subject: Re: [Elecraft] KX3 interal battery charger
>
> The balance charging operation requires access to each cell and requires a
> smart charger that is appropriately programmed for the specific chemistry
> and for the balance operation. The idea is to be sure that each cell is
> properly and fully charged without overcharging or damaging any of the
> other cells in the pack. This is quite common with the all the various
> lithium chemistries, and when using NiCd or NiMh smart chargers that charge
> each cell independently. Most of the inexpensive consumer NiCd and/or NiMh
> chargers do not treat each cell independently. Only the more expensive
> models include the test/refresh modes. Although NiCd and NiMh cells are
> often overcharged by many slow chargers, apparently that is not the best
> practice when performed on a regular basis. Thus, the smart chargers.
>
> If I am understanding correctly, a PbAcid (e.g. SLA) equalize charge
> operation does not have access to each cell and instead is an operation
> that uses a carefully controlled "overcharge" function, within the safe
> "operating envelope" of the battery, to bring up the lagging cells without
> damaging the stronger cells.
>
> It sounds like equalize and balance are two different operations, intended
> for different cell chemistry and charging styles.
>
> Starting with a fresh set of Eneloop (white label 1,900 mAh or black XX
> label 2,500 mAh) or other brand of "pre-charged" or low self-discharge
> (LSD) NiMh batteries that have had at least one test/refresh cycle
> performed, the need for removing the batteries from the KX3 for a
> test/refresh cycle should be VERY infrequent as long as they are not abused
> significantly. As Jim mentioned, hopefully this won't be too often. Who
> knows, even with heavy use, maybe the batteries won't need to be removed
> for over a year - or two. Yes, Greg, I plan to do things exactly as you
> stated: check after a few months, but then pretty much leave them alone in
> the radio for a long while as I see how things work out. I will be
> interested to hear from folks here on the reflector as experience is gained.
>
> With the traditional non-LSD high capacity NiMh batteries, the need for
> test/refresh may be a bit more frequent. For example, the Energizer 2600
> mAh (?) AA cells are notorious for extremely rapid self-discharge and may
> need a bit more care and feeding.
> 72/73 de JP WF4Z
>
>
> On Wed, Jul 4, 2012 at 3:25 PM, Greg Troxel <[hidden email]> wrote:
>
> >
> > In "balance" vs "equalize", I also hear about equalization charge to
> > 12V SLA batteries without access to individual cells. PbAcid cells
> > have a higher charge/discharge marginal ratio as they get full, so a
> > mild overcharge should tend to cause all cells to be fully charged.
> > NiMH is almost certainly similar, especially during low-rate
> > overcharge as is typical, so I'd expect that all cells end up full.
> >
> > To understand the KXBC3 behavior, it seems that one should use a Maha
> > C9000 or equivalent to measure/record the capacity ("refresh/analyze")
> > of all the cells, and then put then in the KX3 and use them for a
> > while, and then when the KX3 says they are charged pull them and do a
> > discharge measurement followed by a refresh/analyze. I'll report back
> > later :-)
> >
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