[Elecraft] K3: power out & V, A readings

[Joe Subich, W4TV]

> Okay, so then did voltage (and amp) readings using the K3 
> itself. Watts are also read from the K3.
> 
> Receive:  13.6  /  0.75

13.6 is a little low.  I would touch up the trimmer on the 
regulator to make the voltage 13.9 or 14.0 on receive.  The 
K3 and particularly any accessory connected to the +12V jack 
will be much happier. 

> 10 / 13.1  /  3.61
> 12 / 13.1  /  3.88
> 13 / 13.3  /  7.48   (KPA kicks in)
> 20 / 13.3  /  8.64

Note the voltage comes back up when the KPA kicks in (the 
current through Q2 drops from about 3.8A to around 2.3A). 
All of these track what I have been seeing. 

73, 

   ... Joe, W4TV 
  



> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of DOUGLAS ZWIEBEL
> Sent: Sunday, December 21, 2008 1:53 PM
> To: Elecraft Reflector
> Subject: [Elecraft] K3: power out & V, A readings
> 
> 
> Well, prompted by the interesting discourse here, I decided 
> to ignore my bulk and get on the floor to make some 
> measurements at the PS (RS35A).
> 
> K3 on Receive: 13.60 volts
> K3 at 120 watts output:  13.59 volts
> 
> Hmmmm.
> 
> Okay, so then did voltage (and amp) readings using the K3 
> itself. Watts are also read from the K3.
> 
> Receive:  13.6  /  0.75
> 
> Xmit :
> watts output / voltage / amps (xmit is CW, key down)
> 0.0 / 13.4  /  1.75
> 1.0 / 13.4  /  2.14
> 2.0 / 13.4  /  2.49
> 3.0 / 13.3  /  2.66
> 4.0 / 13.3  /  2.84
> 5.0 / 13.3  /  2.96
> 10 / 13.1  /  3.61
> 12 / 13.1  /  3.88
> 13 / 13.3  /  7.48   (KPA kicks in)
> 20 / 13.3  /  8.64
> 30 / 13.2  /  10.21
> 40 / 13.2  /  11.38
> 50 / 13.1  /  12.45
> 60 / 13.1  /  13.20
> 70 / 13.1  /  14.07
> 80 / 13.1  /  14.83
> 90 / 13.1  /  15.64
> 100 / 13.0  /  16.40
> 110 / 13.0  /  16.97
> 120 / 12.9 flickering to 13.0  /  17.66
> 
> Well, the Astron appears to be VFB after about 3 decades of 
> service.  :-)
> 
> So...do these numbers tell us anything?
> 
> de Doug KR2Q