[Elecraft] Supply Voltage Range Elecraft K2 transceiver

[Chip Stratton]

As a better and even safer solution, Use LiFePO4 cell x 4 pack for no mote
than 14 Volts from the pack. . Fully charged each cell is 3.3 to 3.5 volts.
At 2.5 volts they are depleted. This type of Lithium rechargeable us also
far more tolerant of overcharging and overdischarge than original LiPo
technology. It is far less prone to catching fire or exploding with
physical or electrical abuse  It is a little more expensive, and not quite
the same power density as regular LiPo, but still beats Lead acid.

I use these for my K2 and KX1 with good results.

Chip
AE5KA

On Thursday, January 12, 2012, Vic K2VCO <k2vco.vic at gmail.com> wrote:
> Would it work to use 4 cells with a couple of series diodes to reduce the
voltage?
>
> On 1/12/2012 1:49 AM, rolf wrote:
>> Elecraft specifies the voltage supply range for the K2 transceiver to
9-15
>> Volts.
>>
>> This range is suitable for lead or nickel batteries. Using Lithium
>> rechargeable batteries it gets somewhat problematic. The voltage range
with
>> a single Lithium Ion (or Li-Polymer) Cell is from 4.2 V (fully charged)
to 3
>> V (lower limit). Using in  a power supply  battery pack 4 cells in
series,
>> the voltage ranges from 16.8 V (max) to 12 V (min). With the K2 as a
load to
>> the battery pack the maximum voltage drops fast down to the plateau
voltage
>> of about 14.5 V. The upper voltage of 16.8 V, however, exceeds the
maximum
>> supply voltage as given by Elecraft.
>>
>> Using 3 Lithium Cells in series, the voltage range will be from 12.6 V
to 9
>> V. This is within the specified  supply voltage of the K2. However, this
>> voltage range is not very suitable for getting the  maximum RF output.
>>
>> Question: Keeping the RF power output and the DC Current of the K" below
the
>> maximum limit, is it possible to apply a supply voltage exceeding 16 V
>> without causing a failure to the electronic components in the K2?
>>
>> Especially for portable operation the use of Li-batteries reduces the
weight
>> in the "rucksack" considerably.
>>
>> Any answer is appreciated.
>>
>> Thanks and 73, Rolf, DL3AO
>>
>>
>>
>> --
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http://elecraft.365791.n2.nabble.com/Supply-Voltage-Range-Elecraft-K2-transceiver-tp7179694p7179694.html
>> Sent from the Elecraft mailing list archive at Nabble.com.
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>
> --
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco/
>
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