Take a look at /Go mobile at 500 watts-SGC /on the web. It gives lots of
good info. I followed the recommendations, including the recommended
Smart Relay and have run 500 watts mobile since 1999 without any hiccups
with my SG500. I have also used this amp powered by a 100 amp-hr deep
cycle RV battery with 12" large battery leads to the amp for 48 hours of
SSB contesting using a 20 amp charger that was able to keep the battery
voltage up with no loss of rated amp power output--nothing fancy, no
caps, no battery booster.
I tried a MFJ switch mode power supply rated for the amp--it lasted less
than 30 seconds.
73, Jim, K7AJM
On 9/11/2016 7:13 AM, Jim Thomson wrote:
Date: Fri, 09 Sep 2016 08:32:58 -0700
From: Larry Dighera <LDighera@att.net>
To: SGC-SmartPowerCube@yahoogroups.com
Cc: "amps@contesting.com" <amps@contesting.com>
Subject: [Amps] SG-500 and N8XJK Super Booster
Has anyone experience using the N8XJK Super Booster
<http://stores.tgelectronics.org/the-n8xjk-super-booster/> with an SG-500
linear amplifier? The battery booster is rated at 40 amps and 16 volts
maximum.
The SG-500 is rated for an input voltage of 14 VDC and an input range of 10 to
18VDC: <http://www.sgcworld.com/ampProductPage.html>. Has anyone attempted to
run the SG-500 at 18VDC? Can the booster do that without issues?
Is the booster able to deal with the rapidly fluctuating 40 amp load the SG-500
creates during SSB output?
What is the optimal location to connect a 2 farad smoothing capacitor, at the
SG-500's power terminals, or at the power input to the battery booster?
Intuitively, I would think the amplifier's power input would be best, but
thought it couldn't hurt to inquire.
Has anyone experienced timing issues between the booster's RF enable trigger
and the amplifier output?
Best regards,
Larry
WB6BBB
## The rapidly fluctuating ssb load will be between idle current...and 90+
amps.
The average load will be 40A. Any power supply will have to be able to handle
90+ amps on peaks.
That booster device is only rated for 40A CCS.... but you will be trying to
suck 90A + out of it
on peaks on ssb /cw. They don’t state a peak current rating for it. Most dc
to dc converters wont handle
more than their rated CCS current. Ditto with most switching supplies.
## is this for mobile use ? Id suggest just using bigger ga cu wire, or 2 x
big gauge wires in parallel,
to limit V drop. The 2+ farad cap will work good though. You would think
that a battery would be like a large
cap, but they are not. The ESR on a battery is a lot more than you think.
Those big 2+ farad caps are low ESR types.
## IF you locate the cap at the back of the amp, the cap has to be charged or
topped up, between ssb /cw peaks.
So you want minimal V drops from amp to battery...IE: big gauge wireS. IF you
put the cap at the battery, then u
don’t have the problem with v drops between cap + battery. But you still need
big gauge wire to the amp.
## 99% of most cars, with engine on, you will see 14.4 vdc right at the
battery............ but typ only 12.2 vdc at the
battery, with engine OFF. IE: alternators will typ put out 14.4 vdc. Newer
alternators are of the 3 phase variety as of
about 2010+. Alternators built in 2009 or prior use single phase.
## Those unregulated DC to regulated + higher DCV units are common place in
the hot rod world. We use em to
increase the loaded vdc at the fuel pump, which is immersed in the gas tank.
The idea is to reduce the fuel pump duty cycle
by increasing the loaded vdc. Typ they are installed in the trunk....AND
larger gauge wire also installed, back to the battery.
Typ output of the unit is a regulated 17 vdc..and most are of the 20 /40 A
variety. But before we go that route, the fuel
pump duty cycle can be reduced 10-15% simply by increasing wire gauge.
## if u are using this for a mobile application, use bigger gauge wire. Then
add the 2 farad cap. Your problems will start when
the engine is OFF, and you only have 12.2 vdc to start with..then it will drop
from there..and fast with a 90+ A peak load.
## Some have used a 6 vdc deep discharge golf cart battery, in series with a
8 vdc deep discharge golf cart battery.... then at least
you have 14.4 vdc to begin with.
## You may well be able to parallel TWO or three of those battery booster
units you linked to..if they divide the output current equally.
But if just a normal sized car battery used, and eng off, you are gonna suck
it flat no matter what you do. You also require a
135-160+ amp alternator to begin with.
## The 2+ farad caps work good on car audio stuff. Without the caps, the
headlights will dim with each bass thump.
Jim VE7RF
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|