Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's a
300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from it. NO
WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out on
contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i presumed
it would be ) as the lap takes about 60w maybe and the transmitter 100w at
times.

Anyway, if someone can please explain why a 300w inverter won't run 160w of
gear i will be very happy.

Thanks

Gary
VK3LCD

"Gary Smith" wrote in message
...
Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's a
300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from it.
NO WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out on
contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i presumed
it would be ) as the lap takes about 60w maybe and the transmitter 100w at
times.

Anyway, if someone can please explain why a 300w inverter won't run 160w
of gear i will be very happy.

It's not so much that it won't RUN the gear, the gear simply won't be very
usable.

The output from these type of inverters is a very strange waveform, a sort
of three step square wave with a ring at each step. And all that noise shows
up in your receiver AND in your transmitter. The filtering in the rig is
just not designed to deal with the complex, harmonic rich waveform at the
output of the inverter. I've even tried running the output through an
isolation transformer, but it did no good at all. You may be able to make it
look somewhat like a sine wave if you could find a proper transformer to
make a tuned tank at 50 Hz, but no telling what voltage you would be getting
out of it. The voltage on my 300 watt 120V/60Hz inverter is 380V peak to
peak (190V peak) with so much garbage in it that my frequency counter can't
even SEE the 60 Hz component.

Gary Smith wrote:
Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's
a 300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from
it. NO WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out
on contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i
presumed it would be ) as the lap takes about 60w maybe and the
transmitter 100w at times.

Anyway, if someone can please explain why a 300w inverter won't run 160w
of gear i will be very happy.

Thanks

Gary
VK3LCD
That radio will run directly on 12 VDC; why the inverter?

http://www.rigpix.com/icom/ic725.htm

Gary Smith wrote:
Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's
a 300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from
it. NO WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out
on contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i
presumed it would be ) as the lap takes about 60w maybe and the
transmitter 100w at times.

Anyway, if someone can please explain why a 300w inverter won't run 160w
of gear i will be very happy.

Thanks

Gary
VK3LCD

That's nuts. 12 VDC to 240 VAC back to 12 VDC for a laptop? Surely
there's a more elegant (in its simplicity) solution.

"Dave" wrote in message
...
Gary Smith wrote:
Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's
a 300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from
it. NO WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out
on contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i
presumed it would be ) as the lap takes about 60w maybe and the
transmitter 100w at times.

Anyway, if someone can please explain why a 300w inverter won't run 160w
of gear i will be very happy.

Thanks

Gary
VK3LCD

That's nuts. 12 VDC to 240 VAC back to 12 VDC for a laptop? Surely
there's a more elegant (in its simplicity) solution.

Probably because the radio likes to see 13.8 not 12.3 v. Big problem when
you do portable OPs. A lot of the laptops need 17-19v too.

There are inverters out there clean enough for that, designed to convert
10-whatever volts to 13.8 regulated for $600 on up. Some that will take
care of the battery charging and automatic battery revert too.

The biggest problem to look out for is ground loops. You could easily wind
up with the Battery negative at ground potential along with antenna and
neutral and have some low voltage component or personnel wind up DEAD with
much anguish left to the survivors.

IF you have designed around that to keep from blowing things up in the heat
of the contest don't expect the 300 watt supply to be able to hack it. If
it doesn't trip right off, you might be OK. But then you still might have
noise and you will have to keep your batteries up some how and if someone
plugs something in you didn't plan for then there's that Death problem
again.

In article ,
"Gary Smith" wrote:

Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's a
300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from it. NO
WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out on
contests and running the laptop and ssb hf rig from it.

Gary-

This is one of those things you can try and see if it will work!

Instead of estimating the power your equipment needs, you need to find a
way measure it. I measured power consumed of an HF rig putting out 100
Watts CW, and found the actual AC consumption was about 350 Watts.

JB-

As far as needing 13.8 Volts instead of 12.3, there is a product on the
market designed just for that problem. One version was published in QST
several years ago, and may be currently marketed by the original author.
Another variation is the MFJ-4416.

Fred
K4DII

On Sep 26, 11:07*pm, Fred McKenzie wrote:
In article ,
*"Gary Smith" wrote:

Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's a
300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from it. NO
WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out on
contests and running the laptop and ssb hf rig from it.

Gary-

This is one of those things you can try and see if it will work!

Instead of estimating the power your equipment needs, you need to find a
way measure it. *I measured power consumed of an HF rig putting out 100
Watts CW, and found the actual AC consumption was about 350 Watts.

JB-

As far as needing 13.8 Volts instead of 12.3, there is a product on the
market designed just for that problem. *One version was published in QST
several years ago, and may be currently marketed by the original author. *
Another variation is the MFJ-4416.

Fred
K4DII

Gee yes: Just because the final amp. of a transmitter is rated 100
watts DC input and may put out 70% of that as RF doesn't mean the
whole unit 'uses' 100 watts!
If it is a tube unit with tubes to heat and standby and a receiever
portion it could easily be consuming several times100 watts. Measure
it!

On Sep 20, 6:42*pm, "JB" wrote:
"Dave" wrote in message

...





Gary Smith wrote:
Hi all, i purchased a 12vdc to 240vac inverter for using my laptop. it's
a 300 watt model fromm Jaycar.
I asked the person running the shop if i could run my 100w IC725 from
it. NO WAY was the reply.

I was thinking of running the DSE D-3800 power supply from it when out
on contests and running the laptop and ssb hf rig from it.
I just wanted to know if it was capable of handling that (which i
presumed it would be ) as the lap takes about 60w maybe and the
transmitter 100w at times.

Anyway, if someone can please explain why a 300w inverter won't run 160w
of gear i will be very happy.

Thanks

Gary
VK3LCD

That's nuts. *12 VDC to 240 VAC back to 12 VDC for a laptop? *Surely
there's a more elegant (in its simplicity) solution.

Probably because the radio likes to see 13.8 not 12.3 v. *Big problem when
you do portable OPs. *A lot of the laptops need 17-19v *too.

There are inverters out there clean enough for that, designed to convert
10-whatever volts to 13.8 regulated *for $600 on up. * Some that will take
care of the battery charging and automatic battery revert too.

The biggest problem to look out for is ground loops. *You could easily wind
up with the Battery negative at ground potential along with antenna and
neutral and have some low voltage component or personnel wind up DEAD with
much anguish left to the survivors.

IF you have designed around that to keep from blowing things up in the heat
of the contest don't expect the 300 watt supply to be able to hack it. *If
it doesn't trip right off, you might be OK. *But then you still might have
noise and you will have to keep your batteries up some how and if someone
plugs something in you didn't plan for then there's that Death problem
again.- Hide quoted text -

- Show quoted text -

Ive never had problems running my 100w PEP ICOM on 12 volts. I suppose
it puts out a little less power. Never measured it on 12 volts.


Jimmie