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[KX3] Hi Curr Warning

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Gary Hawkins

[KX3] Hi Curr Warning

On my last two SOTA outings I've experienced HI CURR warning with the
KX3. I've read this is associated with low battery voltage or low
antenna impedance. I think at one time there was also a software bug
associated with specific settings that was fixed with a firmware release.

My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for
20m. SLA battery, well charged, operating above 12V under load. Antenna
fed from 50ft co-axial cable, 30ft counterpoise connected to ground of
KX3. TX power set to 10W

Both times I was operating on 15 or 10m. ATU was tuned, showing 1:1.0
match.

Does anybody have any idea what is causing the HI CURR warning?

After it happens, TX power reduces to 5W. CMP and ALC bars display - no
matter what I do I can't get these indicators to go in favor of SWR and
RF. Even if I power off the KX3 it still comes up in this display
mode. Finally, for no apparent reason, after five to ten minutes it
then seems to switch back to SWR and RF display.

Looking forward to your input,

Gary
KK6GXD
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DL6OAP

Re: [KX3] Hi Curr Warning

Hi Gary,

The maximum specified output power of the KX3 is 8 Watts on 12, 10 and 6 meters (I think so).
This would explain folding back on 10 but not on 15 meters and certainly does not explain the "display issue".

Greetings

Ralf,DL6OAP

Am 13.12.2013 um 01:36 schrieb Gary Hawkins <[hidden email]>:

> On my last two SOTA outings I've experienced HI CURR warning with the KX3. I've read this is associated with low battery voltage or low antenna impedance. I think at one time there was also a software bug associated with specific settings that was fixed with a firmware release.
>
> My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for 20m. SLA battery, well charged, operating above 12V under load. Antenna fed from 50ft co-axial cable, 30ft counterpoise connected to ground of KX3. TX power set to 10W
>
> Both times I was operating on 15 or 10m. ATU was tuned, showing 1:1.0 match.
>
> Does anybody have any idea what is causing the HI CURR warning?
>
> After it happens, TX power reduces to 5W. CMP and ALC bars display - no matter what I do I can't get these indicators to go in favor of SWR and RF. Even if I power off the KX3 it still comes up in this display mode. Finally, for no apparent reason, after five to ten minutes it then seems to switch back to SWR and RF display.
>
> Looking forward to your input,
>
> Gary
> KK6GXD
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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> Please help support this email list: http://www.qsl.net/donate.html

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Gary Hawkins

Re: [KX3] Hi Curr Warning

In reply to this post by Gary Hawkins

Hi Ron,

Thanks for your response but could you clarify.

On the 12/10m bands I'm not sure of the VSWR of the antenna, but the
VSWR reported by the ATU was 1 to 1, so basically the amp was perfectly
matched and should have been OK. Now the fact that I had the radio set
for 10W rather than 8W on 12/10m might be an issue if the KX3 was over
driving. However, I'd made the assumption that the KX3, knowing it's
band, would just limit automatically - that might not have been correct.

Gary KK6GXD

On 12/12/2013 6:56 PM, Ron D'Eau Claire wrote:

> Not just "low" antenna impedance, but high SWR. The output stage is less
> efficient when the SWR is high so it draws more current to produce the
> requested output.
>
> 73 Ron AC7AC
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Gary Hawkins
> Sent: Thursday, December 12, 2013 4:36 PM
> To: [hidden email]
> Subject: [Elecraft] [KX3] Hi Curr Warning
>
> On my last two SOTA outings I've experienced HI CURR warning with the KX3.
> I've read this is associated with low battery voltage or low antenna
> impedance. I think at one time there was also a software bug associated
> with specific settings that was fixed with a firmware release.
>
> My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for 20m.
> SLA battery, well charged, operating above 12V under load. Antenna fed from
> 50ft co-axial cable, 30ft counterpoise connected to ground of KX3. TX power
> set to 10W
>
> Both times I was operating on 15 or 10m. ATU was tuned, showing 1:1.0
> match.
>
> Does anybody have any idea what is causing the HI CURR warning?
>
> After it happens, TX power reduces to 5W. CMP and ALC bars display - no
> matter what I do I can't get these indicators to go in favor of SWR and RF.
> Even if I power off the KX3 it still comes up in this display mode.
> Finally, for no apparent reason, after five to ten minutes it then seems to
> switch back to SWR and RF display.
>
> Looking forward to your input,
>
> Gary
> KK6GXD
> ______________________________________________________________
> 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
>
>

Gary Hawkins

Re: [KX3] Hi Curr Warning

Hi Gerry,

The unit does not appear to be hot.

Gary

On 12/13/2013 4:20 AM, Gerry leary wrote:

> Is the radio getting too hot?
>
> Sent from my iPhone this time
>
>> On Dec 12, 2013, at 9:11 PM, Gary Hawkins <[hidden email]> wrote:
>>
>> Hi Ron,
>>
>> Thanks for your response but could you clarify.
>>
>> On the 12/10m bands I'm not sure of the VSWR of the antenna, but the VSWR reported by the ATU was 1 to 1, so basically the amp was perfectly matched and should have been OK. Now the fact that I had the radio set for 10W rather than 8W on 12/10m might be an issue if the KX3 was over driving. However, I'd made the assumption that the KX3, knowing it's band, would just limit automatically - that might not have been correct.
>>
>> Gary KK6GXD
>>
>>
>>> On 12/12/2013 6:56 PM, Ron D'Eau Claire wrote:
>>> Not just "low" antenna impedance, but high SWR. The output stage is less
>>> efficient when the SWR is high so it draws more current to produce the
>>> requested output.
>>>
>>> 73 Ron AC7AC
>>>
>>> -----Original Message-----
>>> From: [hidden email]
>>> [mailto:[hidden email]] On Behalf Of Gary Hawkins
>>> Sent: Thursday, December 12, 2013 4:36 PM
>>> To: [hidden email]
>>> Subject: [Elecraft] [KX3] Hi Curr Warning
>>>
>>> On my last two SOTA outings I've experienced HI CURR warning with the KX3.
>>> I've read this is associated with low battery voltage or low antenna
>>> impedance. I think at one time there was also a software bug associated
>>> with specific settings that was fixed with a firmware release.
>>>
>>> My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for 20m.
>>> SLA battery, well charged, operating above 12V under load. Antenna fed from
>>> 50ft co-axial cable, 30ft counterpoise connected to ground of KX3. TX power
>>> set to 10W
>>>
>>> Both times I was operating on 15 or 10m. ATU was tuned, showing 1:1.0
>>> match.
>>>
>>> Does anybody have any idea what is causing the HI CURR warning?
>>>
>>> After it happens, TX power reduces to 5W. CMP and ALC bars display - no
>>> matter what I do I can't get these indicators to go in favor of SWR and RF.
>>> Even if I power off the KX3 it still comes up in this display mode.
>>> Finally, for no apparent reason, after five to ten minutes it then seems to
>>> switch back to SWR and RF display.
>>>
>>> Looking forward to your input,
>>>
>>> Gary
>>> KK6GXD
>>> ______________________________________________________________
>>> 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

KE6BB

Re: [KX3] Hi Curr Warning

In reply to this post by DL6OAP

Gary,

The 8 watts that Ralf mentions is correct, but according to the KX3 specifications (Owner's Manual rev. B4, Pg 51), that is possible when using a 13.8 VDC power source. Although I haven't used one for some time, I would be surprised if an SLA battery voltage is that high during transmit. On 15m, It should be able to provide 10w PEP, but only with a 13.8v power supply. Reduce the power setting a few watts, and you may eliminate the problem.

The KX3 works differently than the rigs most of us have used (other than Elecraft rigs). When you set the power control to an output power, you are not adjusting the drive into the finals, but instead, you are telling the microprocessor that you want that much power out. The microprocessor then controls drive to the finals to get that output power. As the battery voltage drops, the KX3 microprocessor increases the current level (drive current) to get the requested power out. It is a closed loop system. Since P = E x I, the current must be increased as the voltage goes down to keep P constant at the value you requested. At some point, the KX3 current monitoring notes that too much current is being drawn, reduces the power output to protect itself, and displays the HI CURR message.

This has been discussed at great length in the Yahoo KX3 group. Not sure if it has on the Elecraft list. I believe someone there put a table together that shows possible out possible vs. power supply voltage. If I can find it I will reproduce it here, with the proper credit, of course.

Mark
KE6BB

From: Ralf Wilhelm<[hidden email]>
Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎2‎:‎24‎ ‎AM
To: Gary Hawkins <[hidden email]>
CC: [hidden email] <[hidden email]>
Subject: Re: [Elecraft] [KX3] Hi Curr Warning

Hi Gary,The maximum specified output power of the KX3 is 8 Watts on 12, 10 and 6 meters (I think so).This would explain folding back on 10 but not on 15 meters and certainly does not explain the "display issue".GreetingsRalf,DL6OAPAm 13.12.2013 um 01:36 schrieb Gary Hawkins <[hidden email]>:> On my last two SOTA outings I've experienced HI CURR warning with the KX3. I've read this is associated with low battery voltage or low antenna impedance. I think at one time there was also a software bug associated with specific settings that was fixed with a firmware release.> > My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for 20m. SLA battery, well charged, operating above 12V under load. Antenna fed from 50ft co-axial cable, 30ft counterpoise connected to ground of KX3. TX power set to 10W> > Both times I was operating on 15 or 10m. ATU was tuned, showing 1:1.0 match.> > Does anybody have any idea what is causing the HI CURR
warning?> > After it happens, TX power reduces to 5W. CMP and ALC bars display - no matter what I do I can't get these indicators to go in favor of SWR and RF. Even if I power off the KX3 it still comes up in this display mode. Finally, for no apparent reason, after five to ten minutes it then seems to switch back to SWR and RF display.> > Looking forward to your input,> > Gary> KK6GXD> ______________________________________________________________> 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 listHome: http://mailman.qth.net/mailman/listinfo/elecraftHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:[hidden email] list hosted by:
http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.html
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Don Wilhelm-4

Re: [KX3] Hi Curr Warning

In reply to this post by Gary Hawkins

The KX3 and all other Elecraft transceivers that use a similar power
control mechanism will attempt to maintain the requested power output.

If the power supply voltage drops, the current must increase to maintain
the requested power output.
That often means that the High Current threshold will be reached even
though everything is OK.
So check the supply voltage if you see High Current indicated -
especially if operating on an external battery.

73,
Don W3FPR

On 12/13/2013 10:59 AM, Gary Hawkins wrote:

> Hi Gerry,
>
> The unit does not appear to be hot.
>
> Gary
>
> On 12/13/2013 4:20 AM, Gerry leary wrote:
>> Is the radio getting too hot?
>>
>> Sent from my iPhone this time
>>
>>> On Dec 12, 2013, at 9:11 PM, Gary Hawkins <[hidden email]> wrote:
>>>
>>> Hi Ron,
>>>
>>> Thanks for your response but could you clarify.
>>>
>>> On the 12/10m bands I'm not sure of the VSWR of the antenna, but the
>>> VSWR reported by the ATU was 1 to 1, so basically the amp was
>>> perfectly matched and should have been OK. Now the fact that I had
>>> the radio set for 10W rather than 8W on 12/10m might be an issue if
>>> the KX3 was over driving. However, I'd made the assumption that the
>>> KX3, knowing it's band, would just limit automatically - that might
>>> not have been correct.
>>>
>>> Gary KK6GXD
>>>
>

Gary Hawkins

Re: [KX3] Hi Curr Warning

In reply to this post by KE6BB

Hi Mark,

I have revision C2 of the manual and, if I remember correctly, the
important power voltage setting is >11V for full power. That being
said, if 13.8V is what is required this may explain what's going on.
The SLA nominal voltage is marginal. I'm going to purchase some
Lifepo/Lipo batteries to both reduce weight in pack and provide a
slightly higher nominal voltage.

I'm not a member of the Yahoo KX3 user group - perhaps I should join.
If you do find the table you referenced I'd love to see it.

Best regards,

Gary

On 12/13/2013 8:18 AM, Mark Petiford wrote:

> Gary,
>
> The 8 watts that Ralf mentions is correct, but according to the KX3
> specifications (Owner's Manual rev. B4, Pg 51), that is possible when
> using a 13.8 VDC power source. Although I haven't used one for some
> time, I would be surprised if an SLA battery voltage is that high
> during transmit. On 15m, It should be able to provide 10w PEP, but
> only with a 13.8v power supply. Reduce the power setting a few watts,
> and you may eliminate the problem.
>
> The KX3 works differently than the rigs most of us have used (other
> than Elecraft rigs). When you set the power control to an output
> power, you are not adjusting the drive into the finals, but instead,
> you are telling the microprocessor that you want that much power out.
> The microprocessor then controls drive to the finals to get that
> output power. As the battery voltage drops, the KX3 microprocessor
> increases the current level (drive current) to get the requested power
> out. It is a closed loop system. Since P = E x I, the current must be
> increased as the voltage goes down to keep P constant at the value you
> requested. At some point, the KX3 current monitoring notes that too
> much current is being drawn, reduces the power output to protect
> itself, and displays the HI CURR message.
>
> This has been discussed at great length in the Yahoo KX3 group. Not
> sure if it has on the Elecraft list. I believe someone there put a
> table together that shows possible out possible vs. power supply
> voltage. If I can find it I will reproduce it here, with the proper
> credit, of course.
>
>
> Mark
> KE6BB
>
> From: Ralf Wilhelm<[hidden email]>
> Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎2‎:‎24‎ ‎AM
> To: Gary Hawkins <[hidden email]>
> CC: [hidden email] <[hidden email]>
> Subject: Re: [Elecraft] [KX3] Hi Curr Warning
>
> Hi Gary,
>
> The maximum specified output power of the KX3 is 8 Watts on 12, 10 and
> 6 meters (I think so).
> This would explain folding back on 10 but not on 15 meters and
> certainly does not explain the "display issue".
>
> Greetings
>
> Ralf,DL6OAP
>
> Am 13.12.2013 um 01:36 schrieb Gary Hawkins <[hidden email]>:
>
> > On my last two SOTA outings I've experienced HI CURR warning with
> the KX3. I've read this is associated with low battery voltage or low
> antenna impedance. I think at one time there was also a software bug
> associated with specific settings that was fixed with a firmware release.
> >
> > My setup consists of KX3, with ATU, 1/4 wavelength vertical cut for
> 20m. SLA battery, well charged, operating above 12V under load.
> Antenna fed from 50ft co-axial cable, 30ft counterpoise connected to
> ground of KX3. TX power set to 10W
> >
> > Both times I was operating on 15 or 10m. ATU was tuned, showing
> 1:1.0 match.
> >
> > Does anybody have any idea what is causing the HI CURR warning?
> >
> > After it happens, TX power reduces to 5W. CMP and ALC bars display -
> no matter what I do I can't get these indicators to go in favor of SWR
> and RF. Even if I power off the KX3 it still comes up in this display
> mode. Finally, for no apparent reason, after five to ten minutes it
> then seems to switch back to SWR and RF display.
> >
> > Looking forward to your input,
> >
> > Gary
> > KK6GXD
> > ______________________________________________________________
> > 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
>

KE6BB

Re: [KX3] Hi Curr Warning

In reply to this post by Gary Hawkins

Gary,I didn't find the table, but I did find two relevant posts:
This was the problem reported by one poster:
>>During xmit at modest power 8 - 9 watts, I occasionally see a msg flash on the display that shows "hi curr". It seems that when that happens, the xmit power gets reset to 5.0 watts. I have the battery charger option installed and NiMH batteries in the unit, but have been running from an external 12v gel cell.Sounds quite similar to your experience. There was a response from Myron, WV0H, who has done considerable testing on his KX3:>>8-9V will allow you 3W on any band.>>9-11V will allow you 5W on any band.>>11-13V will allow you 10W on 160-15m, 8W on 12-6m, and HI CURR if you exceed 2.5A.>>13-15V will allow you 12W on 160-15m and HI CURR if you exceed 3.0A, or if on 12-6m HI CURR
if you exceed 2.5A. >>If the HI CURR warning shows up, expect to see the power setting throttled back.I have tested some of these data points and my results are very similar to Myron's. In addition, I took a look at some SLA datasheets, and would be very surprised if the voltage at the KX3 during transmit stays above 11v for long. The discharge curve (NOT the same thing as the resting curve, or the charge curve) for SLA's is pretty steep. Combine that with the relatively high internal resistance of the cells, cable/connector drop, and the KX3's reverse polarity protection, and the voltage at the KX3's Power Amplifier tends to get knocked down a lot. I ran successfully ran SLA's for a while after receiving my KX3, but only at 5w and below.I suspect your decision to move to Lifepo/Lipo cells is the right answer if you want to stay in the 8-10 watt range. There are lots of folks using them successfully for that reason.MarkKE6BBFrom: Gary
[hidden email]>Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎9‎:‎04‎ ‎AMTo: Mark Petiford [hidden email]>; [hidden email] [hidden email]>Subject: Re: [Elecraft] [KX3] Hi Curr WarningHi Mark,I have revision C2 of the manual and, if I remember correctly, theimportant power voltage setting is >11V for full power. Thatbeing said, if 13.8V is what is required this may explain what'sgoing on. The SLA nominal voltage is marginal. I'm going topurchase some Lifepo/Lipo batteries to both reduce weight in packand provide a slightly higher nominal voltage. I'm not a member of the Yahoo KX3 user group - perhaps I shouldjoin. If you do find the table you referenced I'd love to see it.Best regards,Gary
______________________________________________________________
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KE6BB

Re: [KX3] Hi Curr Warning

Sorry about the post with only one big paragraph. Sometimes when I trim the post in Yahoo's Win8 e-mail client, it removes the formatting, too.

Mark
KE6BB

From: Mark Petiford<[hidden email]>
Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎10‎:‎39‎ ‎AM
To: Gary Hawkins <[hidden email]>; <[hidden email]>
Subject: Re: [Elecraft] [KX3] Hi Curr Warning

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Help: http://mailman.qth.net/mmfaq.htm
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Gary Hawkins

Re: [KX3] Hi Curr Warning

In reply to this post by KE6BB

Hi Mark,

Thanks, this seems to be the best explanation as to why the Hi Cur
warning is happening.

I'm now trying to decide whether to go for LifePo or LiPo. I like fact
LiPo have higher voltage per cell thus creating a nominal working
voltage around 14.8V but I will likely go for LifePo (nominal working
voltage 13.2V) since they seem a lot safer during charging process.

Gary
KK6GXD

On 12/13/2013 10:01 AM, Mark Petiford wrote:

> Gary,
>
> I didn't find the table, but I did find two relevant posts:
>
> This was the problem reported by one poster:
>
> >>During xmit at modest power 8 - 9 watts, I occasionally see a msg
> flash on the display that shows "hi curr". It seems that when that
> happens, the xmit power gets reset to 5.0 watts. I have the battery
> charger option installed and NiMH batteries in the unit, but have been
> running from an external 12v gel cell.
>
> Sounds quite similar to your experience. There was a response from
> Myron, WV0H, who has done considerable testing on his KX3:
>
> >>8-9V will allow you 3W on any band.
> >>9-11V will allow you 5W on any band.
> >>11-13V will allow you 10W on 160-15m, 8W on 12-6m, and HI CURR if
> you exceed 2.5A.
> >>13-15V will allow you 12W on 160-15m and HI CURR if you exceed 3.0A,
> or if on 12-6m HI CURR
> if you exceed 2.5A.
> >>If the HI CURR warning shows up, expect to see the power setting
> throttled back.
>
> I have tested some of these data points and my results are very
> similar to Myron's. In addition, I took a look at some SLA datasheets,
> and would be very surprised if the voltage at the KX3 during transmit
> stays above 11v for long. The discharge curve (NOT the same thing as
> the resting curve, or the charge curve) for SLA's is pretty steep.
> Combine that with the relatively high internal resistance of the
> cells, cable/connector drop, and the KX3's reverse polarity
> protection, and the voltage at the KX3's Power Amplifier tends to get
> knocked down a lot. I ran successfully ran SLA's for a while after
> receiving my KX3, but only at 5w and below.
>
> I suspect your decision to move to Lifepo/Lipo cells is the right
> answer if you want to stay in the 8-10 watt range. There are lots of
> folks using them successfully for that reason.
>
> Mark
> KE6BB
>
> From: Gary [hidden email]>
> Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎9‎:‎04‎ ‎AM
> To: Mark Petiford [hidden email]>; [hidden email]
> [hidden email]>
> Subject: Re: [Elecraft] [KX3] Hi Curr Warning
>
> Hi Mark,
>
> I have revision C2 of the manual and, if I remember correctly,
> theimportant power voltage setting is >11V for full power. Thatbeing
> said, if 13.8V is what is required this may explain what'sgoing on.
> The SLA nominal voltage is marginal. I'm going topurchase some
> Lifepo/Lipo batteries to both reduce weight in packand provide a
> slightly higher nominal voltage.
>
> I'm not a member of the Yahoo KX3 user group - perhaps I shouldjoin.
> If you do find the table you referenced I'd love to see it.
>
> Best regards,
>
> Gary
>

Gary Hawkins

Re: [KX3] Hi Curr Warning

Hi Gerry,

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capacity
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collision over charged or short circuit; hi thermal stability of phases
up to 500C
3.2V per cell, thus 4 cell pack nominal voltage 13.2V

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Even higher performance, 210mah/g - very light weight for capacity
Shorter Cycle Life: up to 500 recharges.
Unstable Chemistry: can explode or catch fire during charging. Can only
use with specialized chargers
Used extensively with RC vehicles requiring light weight - high current
discharge
3.7V per cell, thus 4 cell pack nominal voltage 14.8V

Both are possibilities for portable operation with KX3 (LiPo need a
little voltage reduction circuitry to keep it under 15V at full
charge). Both much lighter an equivalent Sealed Lead Acid battery.

See this page for further details -
http://www.batteryspace.com/hi-powerli-popacks.aspx.

Hope this helps,

Gary

On 12/15/2013 3:32 PM, Gerry leary wrote:

> Can anyone tell me the differences between the two types of batteries mentioned in this email?
>
> Sent from my iPhone this time
>
>> On Dec 15, 2013, at 3:50 PM, Gary Hawkins <[hidden email]> wrote:
>>
>> Hi Mark,
>>
>> Thanks, this seems to be the best explanation as to why the Hi Cur warning is happening.
>>
>> I'm now trying to decide whether to go for LifePo or LiPo. I like fact LiPo have higher voltage per cell thus creating a nominal working voltage around 14.8V but I will likely go for LifePo (nominal working voltage 13.2V) since they seem a lot safer during charging process.
>>
>> Gary
>> KK6GXD
>>
>>
>>> On 12/13/2013 10:01 AM, Mark Petiford wrote:
>>> Gary,
>>>
>>> I didn't find the table, but I did find two relevant posts:
>>>
>>> This was the problem reported by one poster:
>>>
>>>>> During xmit at modest power 8 - 9 watts, I occasionally see a msg flash on the display that shows "hi curr". It seems that when that happens, the xmit power gets reset to 5.0 watts. I have the battery charger option installed and NiMH batteries in the unit, but have been running from an external 12v gel cell.
>>> Sounds quite similar to your experience. There was a response from Myron, WV0H, who has done considerable testing on his KX3:
>>>
>>>>> 8-9V will allow you 3W on any band.
>>>>> 9-11V will allow you 5W on any band.
>>>>> 11-13V will allow you 10W on 160-15m, 8W on 12-6m, and HI CURR if you exceed 2.5A.
>>>>> 13-15V will allow you 12W on 160-15m and HI CURR if you exceed 3.0A, or if on 12-6m HI CURR
>>> if you exceed 2.5A.
>>>>> If the HI CURR warning shows up, expect to see the power setting throttled back.
>>> I have tested some of these data points and my results are very similar to Myron's. In addition, I took a look at some SLA datasheets, and would be very surprised if the voltage at the KX3 during transmit stays above 11v for long. The discharge curve (NOT the same thing as the resting curve, or the charge curve) for SLA's is pretty steep. Combine that with the relatively high internal resistance of the cells, cable/connector drop, and the KX3's reverse polarity protection, and the voltage at the KX3's Power Amplifier tends to get knocked down a lot. I ran successfully ran SLA's for a while after receiving my KX3, but only at 5w and below.
>>>
>>> I suspect your decision to move to Lifepo/Lipo cells is the right answer if you want to stay in the 8-10 watt range. There are lots of folks using them successfully for that reason.
>>>
>>> Mark
>>> KE6BB
>>>
>>> From: Gary [hidden email]>
>>> Sent: ‎Fri, ‎Dec‎ ‎13‎, ‎2013 at ‎9‎:‎04‎ ‎AM
>>> To: Mark Petiford [hidden email]>; [hidden email] [hidden email]>
>>> Subject: Re: [Elecraft] [KX3] Hi Curr Warning
>>>
>>> Hi Mark,
>>>
>>> I have revision C2 of the manual and, if I remember correctly, theimportant power voltage setting is >11V for full power. Thatbeing said, if 13.8V is what is required this may explain what'sgoing on. The SLA nominal voltage is marginal. I'm going topurchase some Lifepo/Lipo batteries to both reduce weight in packand provide a slightly higher nominal voltage.
>>>
>>> I'm not a member of the Yahoo KX3 user group - perhaps I shouldjoin. If you do find the table you referenced I'd love to see it.
>>>
>>> Best regards,
>>>
>>> Gary
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>>
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Tighe Kuykendall

Re: [KX3] Hi Curr Warning

In reply to this post by Don Wilhelm-4

Similar issue here for a while.

When I first built the KX3 it calibrated out using the KX3 utility
fine. Several months later (Summer 2013) I was at the bench and re-ran
the calibrations using a power supply and dummy load. Cal failed on 10m
with High Current. I upgraded firmware and checked everything I could
think of including doing the calibrations manually. Called Elecraft
support to discuss and decided I should check all mechanical connections
inside the KX3. I disassembled and tightened everything. Still no luck
to date with the calibration above 10M. Luckily I don't operate the KX3
on 10/6m much, so living with a 5W limit is tolerable. Although a
solution would be nice.

Tighe
NK4I

On 12/13/13 11:25 AM, Don Wilhelm wrote:

> The KX3 and all other Elecraft transceivers that use a similar power
> control mechanism will attempt to maintain the requested power output.
>
> If the power supply voltage drops, the current must increase to
> maintain the requested power output.
> That often means that the High Current threshold will be reached even
> though everything is OK.
> So check the supply voltage if you see High Current indicated -
> especially if operating on an external battery.
>
> 73,
> Don W3FPR
>
> On 12/13/2013 10:59 AM, Gary Hawkins wrote:
>> Hi Gerry,
>>
>> The unit does not appear to be hot.
>>
>> Gary
>>
>> On 12/13/2013 4:20 AM, Gerry leary wrote:
>>> Is the radio getting too hot?
>>>
>>> Sent from my iPhone this time
>>>
>>>> On Dec 12, 2013, at 9:11 PM, Gary Hawkins <[hidden email]>
>>>> wrote:
>>>>
>>>> Hi Ron,
>>>>
>>>> Thanks for your response but could you clarify.
>>>>
>>>> On the 12/10m bands I'm not sure of the VSWR of the antenna, but
>>>> the VSWR reported by the ATU was 1 to 1, so basically the amp was
>>>> perfectly matched and should have been OK. Now the fact that I had
>>>> the radio set for 10W rather than 8W on 12/10m might be an issue if
>>>> the KX3 was over driving. However, I'd made the assumption that the
>>>> KX3, knowing it's band, would just limit automatically - that might
>>>> not have been correct.
>>>>
>>>> Gary KK6GXD
>>>>
>>
>
> ______________________________________________________________
> 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

Tighe Kuykendall

Re: [KX3] Hi Curr Warning

Sorry about the empty message. Not sure what happened.

Wanted to close the loop on this. Thanks to those that responded off-list.

I was running MCU 1.57 firmware which is where I was seeing high current
warnings. I hadn't noticed the changes in MCU 1.61 but just upgraded to
MCU 1.79 and can now complete the calibration. All good now!

73, Tighe

Tighe Kuykendall
NK4I | www.NK4I.com <http://www.NK4I.com> | Follow Me on Twitter: @NK4I
ARRL Life Member, NAQCC #6467

On 12/21/13, 9:25 AM, Tighe Kuykendall wrote:

> Similar issue here for a while.
>
> When I first built the KX3 it calibrated out using the KX3 utility
> fine. Several months later (Summer 2013) I was at the bench and
> re-ran the calibrations using a power supply and dummy load. Cal
> failed on 10m with High Current. I upgraded firmware and checked
> everything I could think of including doing the calibrations
> manually. Called Elecraft support to discuss and decided I should
> check all mechanical connections inside the KX3. I disassembled and
> tightened everything. Still no luck to date with the calibration
> above 10M. Luckily I don't operate the KX3 on 10/6m much, so living
> with a 5W limit is tolerable. Although a solution would be nice.
>
> Tighe
> NK4I
>