[Elecraft] K3-Front panel shut down question.

[Lu Romero]

Don:

Depends on the UPS...

in the case of APC, the "Back-Ups" models are "Standby"
types, and yes, the inverters only run when the AC fails and
power is being drawn by the batteries.

However, in the case of APC "Smart-UPS", "Back-UPS Pro" and
TrippLite "SmartPro" models, these are "Line Interactive"
types and the inverter is ALWAYS on, when AC is on, it
charges the battery, but when AC is off it powers the AC
output.

In all cases of the above, some, mostly the less expensive
APC models, are "Modified Sine Wave" which is a rather nasty
looking stepped square wave like waveform with lots of
harmonics.  TrippLite UPS's, at least the SmartPro models I
use at work, are very close if not identical to true sine
wave output.  Check with a scope before placing these
anywhere near a receiver. 

I learned this the hard way with a company surplus APC 1kw
unit that I brought home, re-batteried and put into service
on my shack PC's.  This UPS made 40 and 80 meters unuseable.
 Removing it and replacing it with a pair of APC 500w
Back-Ups (the cheap $40 Office Depot ones) cured the problem
while on AC power.

I agree; If you want to do an "orderly" shutdown, a simple
STANDBY mode UPS will allow you to do this. If you want to
keep transmitting, the West Mountain PowerGate is a great
solution.  See your local Server Farm Administrator and buy
him/her lunch so he/she will think of you when he/she
replaces the Farm's UPS batteries every couple of years on a
set schedule.  

Recently pulled sealed AGM-type ex-UPS batteries will still
have a couple of years life left in them when replaced by
these guys.  They are great for this duty... They are the
size of a automobile wet cell, maybe a little bigger, but
bring your hand cart, these suckers are really, really
heavy! :)

BTW, Im getting used to the "backwards" SPAN control on my
P3; mentally uncoupling WIDTH from SPAN helped.  I will have
my feeble mind retrained probably by the end of my NAQP SSB
shift from my club this weekend... :)

-lu-w4lt-

----------------

Message: 6
Date: Thu, 18 Aug 2011 14:42:25 -0400
From: Don Wilhelm <w3fpr at embarqmail.com>
Subject: Re: [Elecraft] K3-Front panel shut down question.
To: elecraft at mailman.qth.net
Message-ID: <4E4D5D11.2030403 at embarqmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Someone also mentioned that the UPS might generate some hash
- BUT that 
would only be true if the AC is removed from the UPS.  Under
normal 
conditions with AC present, the inverter is not active.

It was not the initial question, but -- if you want to keep
transmitting 
after an outage, you will have to implement the large
battery solutions 
that have been mentioned.

73,
Don W3FPR