Doc,
That's one monster of a converter! Doc, since you periodically mention
various inverters and power supplies in your posts, I presume that you
have need for such devices. When considering such devices, keep in mind
the following:
1. They draw a LOT of current at 13.6 VDC. In this case, at 5000 watts
output @ 90% efficiency, the input draw will be 408 amps!!! I hope you
have a battery and charging system that can handle that. (I read some of
the review comments at the web site where your link leads to and laughed
my self silly about guys toasting their vehicle alternators. I think they
were a little short-sighted in being able to handle the beast.)
2. The device produces a modified sine wave output and weighs only 21
pounds for a 5 kW device. Those two facts tell me that the heart of the
beast is a high frequency inverter in which a 60 Hz sine wave is
synthesized so that they do not have to use any 60 Hz magnetics. If they
did, the weight would be hundreds of pounds for a 5000 watt unit. You can
be sure that there is a LOT of hash flying around from this thing,
probably on both the input and output connections.
3. They mention EMI, but make no statement about conforming to any
specific standard. Note that concrete drills and other construction tools
don't care much about hash on their power cords.
I've said this before, and I'll say it again: do NOT buy or attempt to
use power supplies and power inverters that are not designed expressly for
communications applications unless you are prepared to tackle the fix
yourself. I saw that this device sells for nearly $600. My guess is that
you'll need several hundred dollars more to spend on the filtering,
especially for the input side. It can be a challenge making inductors for
a filter when you are working with welding cable! The alternative is to
locate this monster well away from any 160m or HF antennas so that its
racket doesn't drive you nuts. I would guess that 50 feet would be a good
start, and you might need to go further than that. You would probably
have to filter the 120V output just to keep from polluting your shack and
home woth noisy power.
Quite frankly, I'd suggest a modern 5000 watt engine-driven alternator as
a better bet for this power level. Cost is about the same and alternator
power is clean. Most gen sets these days have noise suppressed ignition
systems.
On a related topic, I happened to be looking on eHam the other day at some
product reviews on switching power supplies for amateur radio use. It is
a sad thing to say, but some manufacturers just have to shave corners in
anyway they can and thus put the hurt on any buyers who don't pay minute
attention to detail when making a buy. There appears to be at least one
brand of switcher out there (and no, it is not Astron or MFJ) that is
meant for communication applications, but is NOT friendly for HF use! The
manufacturer seems to think that most buyers are running VHF and above
rigs, so the hash that is generated by the switcher is not well-suppressed
within the unit. One buyer spent several dollars adding filtering to make
his unit usable with his HF radios.
I have no connection whatever with Astron, but my SS-30M continues to
power my HF and VHF/UHF gear just fine with no issues. It also did very
well in ARRL lab tests in 2002. There are others that are nearly as good
for noise suppression, but none I have seen that are any better. I use
that switcher both at home and at Field Day. In FD use, the antennas are
right above (or otherwise close) to the power supply and no problems. Go
to the ARRL web site and assuming that you are a member, you can check out
the League's product test of the Astron and several others switchers.
Check it out - good reading!
73, Dale
WA9ENA
kd4e <doc@kd4e.com>
Sent by: rfi-bounces@contesting.com
09/14/2008 08:46 PM
Please respond to
doc@kd4e.com
To
RFI List <rfi@contesting.com>, "tvi-rfi-emi@mailman.qth.net"
<tvi-rfi-emi@mailman.qth.net>
cc
Subject
[RFI] Aims 5000 Watt MSW Power Inverter
Anyone have any experience with this inverter, please?
Aims 5000 Watt MSW Power Inverter:
http://www.invertersrus.com/inv5000w.html
--
Thanks! & 73, doc, KD4E
Free OS : http://www.PuppyLinux.com
Personal: http://kd4e.com
|_|___|_|
| | & | |
{|
/\ {|
/ \ {|
/ \ {|
/ @ \ {|
| |~_|~~~~|
| -| | |
============\ # KD4E
Have an http://ultrafidian.com day!
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|