Wall wart for KX3

[Ed Picha]

KX3 gurus:

Has anyone found a wall wart they like for the KX3?  Like most hams, I
have a big box of wall warts, and have tried several different 12 V
adaptors with the KX3.  They all worked ok for general operation, but I
noted that when I added the KXBC3 battery charger option to the KX3, I
really needed an honest 13.8 V or higher to fully charge the internal
batteries.  Most of the warts I tried had outputs less than 13V, and the
few that I found that could supply 13.8 V under load had voltages above
15 V with no load.   I didn't want to take a chance with these by
exceeding the KX3 upper voltage speceven for the short time that it
would take for the adaptor voltage to drop.

My KX3 current drain numbers are (all at 13.8 V):

receive, with backlight:  0.190 A
receive while charging batteries: 0.400 A
transmit, 5W: 1.04 A
transmit, 10W: 1.91 A

So, I guess the ideal adaptor would be capable of 2A at 13.8 V to
support running the radio with no (or fully discharged) batteries at
full power, and would not exceed 15 V with no load.  While I'm wishing,
it would also be smalland lightweight.

Any suggestions?

thanks, 73

ed N9EP
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Don Wilhelm-4]

Ed,

I for one would not trust any radio to a wall-wart power supply unless
it stated on the label that it was regulated.

In most cases, the open circuit voltage will soar, and the KX3 maximum
voltage is 15 volts.  Under the supply's rated load, the voltage will
normally reduce to the voltage on the label, but there is usually a wide
swing between no-load and full-load voltages.

I would suggest a real power supply which is rated at 4 amps or more for
the KX3.

My own KX3 runs off an Astron 30 amp supply and is fused for 10 amps to
protect the wire from any fault.

73,
Don W3FPR
On 12/18/2012 9:17 PM, Ed Picha wrote:

> KX3 gurus:
>
> Has anyone found a wall wart they like for the KX3?  Like most hams, I
> have a big box of wall warts, and have tried several different 12 V
> adaptors with the KX3.  They all worked ok for general operation, but
> I noted that when I added the KXBC3 battery charger option to the KX3,
> I really needed an honest 13.8 V or higher to fully charge the
> internal batteries.  Most of the warts I tried had outputs less than
> 13V, and the few that I found that could supply 13.8 V under load had
> voltages above 15 V with no load.   I didn't want to take a chance
> with these by exceeding the KX3 upper voltage speceven for the short
> time that it would take for the adaptor voltage to drop.
>
> My KX3 current drain numbers are (all at 13.8 V):
>
> receive, with backlight:  0.190 A
> receive while charging batteries: 0.400 A
> transmit, 5W: 1.04 A
> transmit, 10W: 1.91 A
>
> So, I guess the ideal adaptor would be capable of 2A at 13.8 V to
> support running the radio with no (or fully discharged) batteries at
> full power, and would not exceed 15 V with no load.  While I'm
> wishing, it would also be smalland lightweight.

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Christian AK4VV]

Enercell wallwart from Radio Shack is what I use and have been happy with
it.

http://www.radioshack.com/product/index.jsp?productId=3875404&numProdsPerPage=60

73,
Christian
AK4VV
 On Dec 18, 2012 9:17 PM, "Ed Picha" <[hidden email]> wrote:

> KX3 gurus:
>
> Has anyone found a wall wart they like for the KX3?  Like most hams, I
> have a big box of wall warts, and have tried several different 12 V
> adaptors with the KX3.  They all worked ok for general operation, but I
> noted that when I added the KXBC3 battery charger option to the KX3, I
> really needed an honest 13.8 V or higher to fully charge the internal
> batteries.  Most of the warts I tried had outputs less than 13V, and the
> few that I found that could supply 13.8 V under load had voltages above 15
> V with no load.   I didn't want to take a chance with these by exceeding
> the KX3 upper voltage speceven for the short time that it would take for
> the adaptor voltage to drop.
>
> My KX3 current drain numbers are (all at 13.8 V):
>
> receive, with backlight:  0.190 A
> receive while charging batteries: 0.400 A
> transmit, 5W: 1.04 A
> transmit, 10W: 1.91 A
>
> So, I guess the ideal adaptor would be capable of 2A at 13.8 V to support
> running the radio with no (or fully discharged) batteries at full power,
> and would not exceed 15 V with no load.  While I'm wishing, it would also
> be smalland lightweight.
>
> Any suggestions?
>
> thanks, 73
>
> ed N9EP
> ______________________________**______________________________**__
> Elecraft mailing list
> Home: http://mailman.qth.net/**mailman/listinfo/elecraft<http://mailman.qth.net/mailman/listinfo/elecraft>
> Help: http://mailman.qth.net/mmfaq.**htm<http://mailman.qth.net/mmfaq.htm>
> Post: mailto:[hidden email].**net <[hidden email]>
>
> 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:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Christian AK4VV]

Agree.  And an Astron RS-35M does the heavy lifting in my shack.  But a
little wallwart can go a long ways when the Astron isn't in reach.

73,
Christian
AK4VV
 On Dec 18, 2012 9:33 PM, "Don Wilhelm" <[hidden email]> wrote:

> Ed,
>
> I for one would not trust any radio to a wall-wart power supply unless it
> stated on the label that it was regulated.
>
> In most cases, the open circuit voltage will soar, and the KX3 maximum
> voltage is 15 volts.  Under the supply's rated load, the voltage will
> normally reduce to the voltage on the label, but there is usually a wide
> swing between no-load and full-load voltages.
>
> I would suggest a real power supply which is rated at 4 amps or more for
> the KX3.
>
> My own KX3 runs off an Astron 30 amp supply and is fused for 10 amps to
> protect the wire from any fault.
>
> 73,
> Don W3FPR
> On 12/18/2012 9:17 PM, Ed Picha wrote:
>
>> KX3 gurus:
>>
>> Has anyone found a wall wart they like for the KX3?  Like most hams, I
>> have a big box of wall warts, and have tried several different 12 V
>> adaptors with the KX3.  They all worked ok for general operation, but I
>> noted that when I added the KXBC3 battery charger option to the KX3, I
>> really needed an honest 13.8 V or higher to fully charge the internal
>> batteries.  Most of the warts I tried had outputs less than 13V, and the
>> few that I found that could supply 13.8 V under load had voltages above 15
>> V with no load.   I didn't want to take a chance with these by exceeding
>> the KX3 upper voltage speceven for the short time that it would take for
>> the adaptor voltage to drop.
>>
>> My KX3 current drain numbers are (all at 13.8 V):
>>
>> receive, with backlight:  0.190 A
>> receive while charging batteries: 0.400 A
>> transmit, 5W: 1.04 A
>> transmit, 10W: 1.91 A
>>
>> So, I guess the ideal adaptor would be capable of 2A at 13.8 V to support
>> running the radio with no (or fully discharged) batteries at full power,
>> and would not exceed 15 V with no load.  While I'm wishing, it would also
>> be smalland lightweight.
>>
>
> ______________________________**______________________________**__
> Elecraft mailing list
> Home: http://mailman.qth.net/**mailman/listinfo/elecraft<http://mailman.qth.net/mailman/listinfo/elecraft>
> Help: http://mailman.qth.net/mmfaq.**htm<http://mailman.qth.net/mmfaq.htm>
> Post: mailto:[hidden email].**net <[hidden email]>
>
> 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:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Bill Frantz]

I have been using the Jameco's #319920, 15V regulated wall-wart
from <http://www.jameco.com> for my Small Wonder Labs PSK-20 as
recommended by the kit's designer. I have not noticed any noise
from the wall wart on 20 meters, the only band supported by the PSK-20.

The wall wart is rated at 18 watts. The PSK-20 has a 5 watt
transmitter, so I don't know if it will run a KX3 at full power.

Because the rated voltage of the wall wart is the same as the
KX3's maximum voltage, I would feel safer putting a diode in
series with it to drop the voltage below the KX3's maximum. A
single diode should give about 14.3 to 14.5 volts, within the
KX3's specification and above the 13.8 volts needed for battery charging.

Cheers - Bill, AE6JV

On 12/18/12 at 6:17 PM, [hidden email] (Ed Picha) wrote:

>Has anyone found a wall wart they like for the KX3?

-----------------------------------------------------------------------
Bill Frantz        | gets() remains as a monument | Periwinkle
[phone]      | to C's continuing support of | 16345
Englewood Ave
www.pwpconsult.com | buffer overruns.             | Los Gatos,
CA 95032

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Josh Lehan]

On 12/18/2012 06:17 PM, Ed Picha wrote:

> Has anyone found a wall wart they like for the KX3?  Like most hams, I
> have a big box of wall warts, and have tried several different 12 V
> adaptors with the KX3.  They all worked ok for general operation, but I
> noted that when I added the KXBC3 battery charger option to the KX3, I
> really needed an honest 13.8 V or higher to fully charge the internal
> batteries.  Most of the warts I tried had outputs less than 13V, and the
> few that I found that could supply 13.8 V under load had voltages above
> 15 V with no load.   I didn't want to take a chance with these by
> exceeding the KX3 upper voltage speceven for the short time that it
> would take for the adaptor voltage to drop.

I had great luck with an old Toshiba laptop's power supply, that I
bought cheaply at a surplus shop (Halted Electronics).

It was from a time before laptop power supplies became "smart", so
there's only 2 leads coming out of it: the DC power.  I cut off the old
Toshiba connector and just connected the bare wires to the supplied
Elecraft connector that also has bare wires, after testing it for
polarity.  The power supply gives a rock solid 15VDC, and it's rated up
to 3A.  My KX3 has no trouble at all when transmitting at the full 12W
power level.  However, I don't have the KXBC3 option, so don't know how
it performs with that.  The model number on it is Toshiba PA2450U.

It is small and lightweight.  It plugs into a 2-prong outlet, not a
3-prong, so I'm assuming it's not grounded.  The only problem is that it
might cause interference/noise.  However, I couldn't notice any.  Where
I'm at, there's a constant buzzing noise all over 40 meters, but the
noise blanker feature of the KX3 seems to solve that.  It's not caused
by this power supply, though: I unplugged it, but the noise remained.

Josh
K6JSH
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[KXBill]

I got a PS for a Respirator from MPJ.  A 12v 4.16 amp unit.  
Runs the K2. and KX3  
It's quite, RF wise.  Take a look at their web site and you will see 16 volt units available.
http://www.mpja.com/Desktop-Power-Supplies/products/475/

Ciao

de w7kxb-Bill . .

> Date: Tue, 18 Dec 2012 20:17:55 -0600
> From: [hidden email]
> To: [hidden email]
> Subject: [Elecraft] Wall wart for KX3
>
> KX3 gurus:
>
> Has anyone found a wall wart they like for the KX3?  
     
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[ke9uw]

I use this one...14 volts, 4 amps. The plug on it fits the KX3 and the open ckt voltage is 14 vdc exactly.

http://www.ebay.com/itm/KSAS065-65W-Adapter-power-supply-Output-14Vdc-4A-2-1mm-plug-NEW-FREE-SHIP-/261135859531?pt=US_Monitor_Power_Supplies&hash=item3ccce8ff4b

Chuck, KE9UW
Lionel Trains, TCA, LCCA, LRRC
aka Jack, BMW Motorcycles BMWMOA #224

________________________________________
From: [hidden email] [[hidden email]] on behalf of Ed Picha [[hidden email]]
Sent: Tuesday, December 18, 2012 8:17 PM
To: [hidden email]
Subject: [Elecraft] Wall wart for KX3

KX3 gurus:

Has anyone found a wall wart they like for the KX3?  Like most hams, I
have a big box of wall warts, and have tried several different 12 V
adaptors with the KX3.  They all worked ok for general operation, but I
noted that when I added the KXBC3 battery charger option to the KX3, I
really needed an honest 13.8 V or higher to fully charge the internal
batteries.  Most of the warts I tried had outputs less than 13V, and the
few that I found that could supply 13.8 V under load had voltages above
15 V with no load.   I didn't want to take a chance with these by
exceeding the KX3 upper voltage speceven for the short time that it
would take for the adaptor voltage to drop.

My KX3 current drain numbers are (all at 13.8 V):

receive, with backlight:  0.190 A
receive while charging batteries: 0.400 A
transmit, 5W: 1.04 A
transmit, 10W: 1.91 A

So, I guess the ideal adaptor would be capable of 2A at 13.8 V to
support running the radio with no (or fully discharged) batteries at
full power, and would not exceed 15 V with no load.  While I'm wishing,
it would also be smalland lightweight.

Any suggestions?

thanks, 73

ed N9EP
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Jim Sheldon]

I have one from MPJA that puts out 12.0 volts @ 4 amps which, as it turns out, is not enough voltage to charge batteries in the KX3 using the internal charger so seeing this one I checked on it further and found a link to the manufacturer's spec sheet.  It looks pretty good.  The supply has over voltage and overcurrent protection, 4.1 amps @ 14 volts and the spec lists it 14.0-14.9 volts so still within the KX3's safe range, especially if it puts out 14.0 like Chuck's does.  

Certainly cheap enough as well, $8.59 with free shipping.  (The MPJA supply was $12.95 plus shipping.) I did order one from eBay and I'll report back to the list after I get it and run some power/RFI tests on it.  From the Mfr. spec sheet, it has very low RF emissions and the output lead is Ferrite choked so hopefully it will be either extremely quiet or any RFI will be out of the ham bands.  Both of them are made in China (what isn't these days except for our favorite Elecraft gear?) however, the quality is very good on the MPJA box and from the pictures, the one from eBay is as well.  

On the MPJA supply, it was originally intended for a respirator used to treat "Sleep Apnea" so it is medical grade and extremely quiet RF wise.  I didn't find any noticeable birdies in any of the ham bands from it and planned to test it further when I saw this post. Hopefully this one on the auction site is just as quiet.  It is certainly a little cheaper than the one from MPJA and it will have enough voltage to operate the KX3 to it's full output as well as charge batteries.  The MPJA one will give 12 watts out, but it's just a bit wimpy in the voltage department for charging batteries.

Neither of these are really "Wall Warts" in the true sense of the words but certainly small and light enough to be considered extremely portable.

Jim - W0EB

> I use this one...14 volts, 4 amps. The plug on it fits the KX3 and
> the open ckt voltage is 14 vdc exactly.
>
> http://www.ebay.com/itm/KSAS065-65W-Adapter-power-supply-Output-
> 14Vdc-4A-2-1mm-plug-NEW-FREE-SHIP-
> /261135859531?pt=US_Monitor_Power_Supplies&hash=item3ccce8ff4b
>
> Chuck, KE9UW
> Lionel Trains, TCA, LCCA, LRRC
> aka Jack, BMW Motorcycles BMWMOA #224
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html