KX3 PS Voltage Display Accuracy?

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

KX3 PS Voltage Display Accuracy?

GeorgeP1111
I have a external TalentCell 12v Li-Ion 12800mAh Battery Pack that I have been testing on my KX3.  At the same connection point as the battery (KX3 9-15vdc Power Input) I have my Fluke 177 multi-meter and a EB_M05 that I use to plot the battery pack voltage discharge.  I noticed that the Fluke 177 and EB_M05 will both read the same battery pack voltage but the KX3 voltage display shows about 0.2v lower on Receive and about 0.6v lower on Transmit, as if there was a series diode involved with the display voltmeter.  The KX3 10w output is rolled back to 5w when the KX3 voltage display drops below 10.0v.  So at this point on transmit where the KX3 is displaying PS 10.0v, the Fluke and EB_M05 are showing 10.6v.  If the KX3 were displaying the same as the Fluke (10.6v) I would have a additional 0.6v @ 2000ma available to support the “Use higher power at 10 V only when necessary to complete critical communications”.



George

WD0AKZ



---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
______________________________________________________________
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
Message delivered to [hidden email]
Reply | Threaded
Open this post in threaded view
|

Re: KX3 PS Voltage Display Accuracy?

John Oppenheimer
On 6/11/19 3:34 PM, George Pasek wrote:
> as if there was a series diode involved with the display voltmeter.

Hi George,

KKX3 uses a series Schottky doide for reverse voltage protection. The
KX3 displays voltage after the diode.

John KN5L
______________________________________________________________
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
Message delivered to [hidden email]
Reply | Threaded
Open this post in threaded view
|

Re: KX3 PS Voltage Display Accuracy?

Nr4c
In reply to this post by GeorgeP1111
I believe the KX3 does have a diode in the line.

Bottom line, the radio doesn’t care what your Fluke says, it uses its own voltmeter and acts on it. I owned a KX3 for a while and felt a bit behind as the radio was introduced with NiMH  battery technology just as LiPO battery technology was just coming into full bloom. If the voltage range were just bumped up to 16-17 Volts. A nice 4X? Pack would be great. A 3X pack is barely enough.

Think the KX2 is now a better deal. But my portable days are over. Sadly.

Sent from my iPhone
...nr4c. bill


> On Jun 11, 2019, at 4:34 PM, George Pasek <[hidden email]> wrote:
>
> I have a external TalentCell 12v Li-Ion 12800mAh Battery Pack that I have been testing on my KX3.  At the same connection point as the battery (KX3 9-15vdc Power Input) I have my Fluke 177 multi-meter and a EB_M05 that I use to plot the battery pack voltage discharge.  I noticed that the Fluke 177 and EB_M05 will both read the same battery pack voltage but the KX3 voltage display shows about 0.2v lower on Receive and about 0.6v lower on Transmit, as if there was a series diode involved with the display voltmeter.  The KX3 10w output is rolled back to 5w when the KX3 voltage display drops below 10.0v.  So at this point on transmit where the KX3 is displaying PS 10.0v, the Fluke and EB_M05 are showing 10.6v.  If the KX3 were displaying the same as the Fluke (10.6v) I would have a additional 0.6v @ 2000ma available to support the “Use higher power at 10 V only when necessary to complete critical communications”.
>
>
>
> George
>
> WD0AKZ
>
>
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

______________________________________________________________
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
Message delivered to [hidden email]