Posted by
N6JW on
Aug 10, 2010; 8:45pm
URL: http://elecraft.85.s1.nabble.com/Elecraft-Power-supply-tp5388972p5404591.html
"How much would you be willing to pay" for an internal
uninterruptible PS in the P3?
Let's see: Working from what we already know . . .
Gamma Research HPS-1a is $169
According to Ron AC7AC there is only 4x4x6" space available in the P3,
so keeping that as a limiting factor, even the following LiFePO4 battery
pack would fit in:
Powerizer's 12.8v (working; 14.6v peak; 10v cutoff) 9.9aH (127WH at
21amp) LiFePO4 battery pack (4S3P) 2lbs, 4.3x3.3x3.4" [since LiFePO4
batteries allow full power operation through more than 95% of its capacity,
this pack would allow for significant operational time at 100w. Also note
this technologies reputation for safety (no fire or explosion risk), 10+ year
lifespan with thousands of full discharge/charge cycles, and quick recharge
times.] Current Price = $154 [$139 in quantity]
Of course, one might not need anything nearly as large as this battery
pack for the intended function! Powerizer also lists a 6.6aH pack for $75.
So one could reasonably surmise that it should be possible to sell an
internal P3 PS along the lines suggested for somewhere between $175 to
$350. At anything like these prices, I would buy it without hesitation.
73
John
N6JW
WILLIS COOKE-2 wrote
How much would you be willing to pay? $300, $500?
Willis 'Cookie' Cooke
K5EWJ
JOHN SAID
Elecraft could design a small (RFI
quiet) switching PS which would constantly recharge an
appropriately sized LiFePO4 battery pack, which in turn would
supply the power needed by the K3/P3 combo (i.e. 25 amps).
In effect this would replace the large caps in the HPS-1a
design, with the LiPo battery. Bottom line: a universal voltage
uninterruptible internal PS.
I agree, and more to the point -- I would buy one.
eric
VA7DZ