Thanks, Bert (nice call)
I started out to share some info with Ian, and things got interesting at my qth.
Some of your measurements are similar to mine. Here are the details of what I
found in case a person is interested:
I used a piece of red/black paired wire from my Astron to my homebrew
distribution. Without disconnecting it, I think it looks a size smaller than
the wire to the K3. I also looked at the fuse holder (buss type) and the wire
on it looks smaller as well. I'm going to replace both with heavier wire.
As for my distribution, I use ground blocks for AC power panels and mount them
in plastic outlet boxes. I solder the ends of my wires before I tighten the
screws down on them. I am not opposed to bypassing the distribution blocks if
need be.
I checked all my manuals for schematics, and finally downloaded them. I
printed out the first six pages. I can see that the 12V out jack is not part
of the ammeter sensing, so the P3 current can be ignored when using the K3
ammeter.
A couple replies said the current draw will vary by band. That is good to know.
I wonder if you made your measurements on the 75/80 meter band as I did. I'm
curious about your mention of the 18 amps tapering down to 14 amps thing.
I need to do as you did and measure the voltage with my DVM at the PS, the
distribution blocks, and the K3 terminals.
>From your readings, I can tell the voltage drop is not nearly as great as it
>appeared by the K3 meter. Using the K3 readings, I have 0.5 volt lower than
>you on key down, and that is acceptable. I should be able to correct that.
And yes, as you said, 'everything works just fine'.
Thanks much,
Rich, n0ce
----- Original Message -----
From: n...@aol.com
To: elecraft@mailman.qth.net
Sent: Wednesday, December 26, 2012 11:56 AM
Subject: Re: [Elecraft] New Output Power Issue, and a new question
First of all, regarding a DC power distribution "strip": I used a RigRuner
4009 and found that there was
a significant voltage drop from the power source (Astron RS-35M) to the K3.
Having taken measurements
with a DVM, I concluded that the largest drop was from the distribution
strip to the K3. A simple solution
was to power the K3 from the larger "main" wire pair that fed the
distribution strip.
Then, to satisfy my own curiosity, I made the following meaurements today
using the DVM then I took readings with the internal K3 "meter":
DVM measurements: 13.773 VDC at the RS-35 terminals
13.735 VDC at K3 connector in RX mode
13.599 VDC at K3 connector in TX-Tune mode
(10W out)
12.860 VDC at K3 connector in TX mode
(100W out)
K3 "meter" readings: 13.6 VDC in RX mode
13.1 VDC in TX-Tune mode (10W out)
12.4 VDC in TX mode (100W out)
What's interesting is that the K3 "meter" current indication decreases with
time when I
make the test in TX mode (100W out), starting at about 18.2 Amps or so,
then going down, down,
down to 14.something when I let up on the hand key. I kept the key down
just 15 or 20 seconds,
not wanting to tempt fate!!! Power output stayed at 100W throught the
procedure. Hmmmm....
I'm satisfied with those readings: everything works just fine!
Bert, N4CW
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
