internal battery - charging

[paulb]

Hello folks

Recently completed a K1, all works well.

A mod here which I know is nqr ( not quite right )
is fitting a simple  internal charger circuit so the batt pack
can be left in situ.

The original cover is also used, with the smaller speaker.
Fit is what could be politely called " snug "

When external 13.5 volts is used, the batts get a very small
charge, about 15 ma. Now here is the tricky bit..when the
K1 is off, but the external supply left plugged in, the charge
rate is approx 200ma.  

Yep I know it's not really correct,  but sure beats taking
the top off to replace cells.

cheers

Paul
zl1ajy

[Mike Morrow-3]

Paul wrote:

>A mod here ... is fitting a simple internal charger circuit so the batt
>pack can be left in situ.
>
>The original cover is also used, with the smaller speaker.  Fit is what
>could be politely called " snug "

By "original cover" I suppose that you actually are refering to the replacement
cover that comes with the KBT1, not the original K1 cover.

>Yep I know it's not really correct, but sure beats taking the top off to
>replace cells.

Maybe not.  The battery pack in the KBT1 is not contained in any way to
prevent corrosive chemical leakage from the rechargeable cells, which
is most likely to occur during charge.

I had a KBT1 installed for 18 months in my K1.  I then removed it completely,
because of the following:

(1)  I disliked the possibility of chemical outgassing and leakage taking place
just above the K1's RF board.
(2)  I also disliked having to remove the pack for charging, yet I could be
comfortable with no lesser approach (see item 1).
(3)  I prefer to use at least 12 vdc as the supply to my K1.  The eight-cell
KBT1 pack is nominally 9.6 vdc.
(4)  I did not like the audio quality from the small KBT1 speaker, compared to
the much larger standard K1 speaker.
(5)  I much preferred the appearance of the original K1 top cover/speaker
assembly, compared to that of the KBT1.

The KBT1 would be much improved if it could be disconnected completely
from the K1's RF circuit board using a male connector mounted ON the RF
board, and a cable with a female connector attached to the KBT1 assembly.
The various disconnects that folks have rigged up allow a loose connector
(sometimes with exposed conductors!) and cable to be floating around in the
K1 after the KBT1 has been removed.  A two-pin male connector ON the RF
board would eliminate this floating cable and connector.

I chose to supply the K1 with an external pack.  I use a 10-cell AA pack
with 2500 mAH cells for short-term operation, and a SLA 4.5 AH, 12.6 vdc,
battery for longer portable operations.  The latter is small, not all that heavy,
and hard to exhaust in a few days, even with heavy continuous operation.

Mike / KK5F
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[paulb]

Hi Mike

The K1 cover is the original supplied with the kit.
Smaller speaker volume is quite a bit lower, but I use a headset so
it's not a big issue for my style of use.

The bracket which the batts/speaker sit in can be slightly
modified to sit lower in the chassis, this allows the kit cover to
sit flat. Looks stock except the front speaker screw holes
are visible. I have put a dyno label accross them with my callsign and
rig serial number...looks ok.

AA batts are sealed but leaks will occur no doubt.
Like I say, it's nqr but sure beats swapping out battery packs.

cheers from downunder

Paul b
zl1ajy
Paul wrote:

>A mod here ... is fitting a simple internal charger circuit so the batt
>pack can be left in situ.
>
>The original cover is also used, with the smaller speaker.  Fit is what
>could be politely called " snug "

By "original cover" I suppose that you actually are refering to the replacement
cover that comes with the KBT1, not the original K1 cover.


(3)
(5)  I much preferred the appearance of the original K1 top cover/speaker
assembly, compared to that of the KBT1.