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Problems with K3 firmware update

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Kurt Wiksten

Problems with K3 firmware update

I was trying to load new firmware to my K3. Present MCU version 04.51.
When started I got some Err message and the Tx lamp blinked and the K3 screen darkend. I tryed to
switch the power off on the K3 but it did not work so I paniced and switched the power supply off.
I have tryed to switch the power on again but it is not possible.
What do I do?? Please help!
Kurt/SM6BGG

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Dick Dievendorff-4

Re: Problems with K3 firmware update

K3 Utility Help, Troubleshooting, MCU Load failure.

73 de Dick, K6KR

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Kurt
Wiksten
Sent: Thursday, August 14, 2014 10:02 AM
To: [hidden email]
Subject: [Elecraft] Problems with K3 firmware update

I was trying to load new firmware to my K3. Present MCU version 04.51.
When started I got some Err message and the Tx lamp blinked and the K3
screen darkend. I tryed to switch the power off on the K3 but it did not
work so I paniced and switched the power supply off.
I have tryed to switch the power on again but it is not possible.
What do I do?? Please help!
Kurt/SM6BGG

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Kurt Wiksten

Re: Problems with K3 firmware update

In reply to this post by Kurt Wiksten

Thanks to everybody for your advice.
But my problem still not solved, because I am communicating with the K3 via
my Microkeyer2.
Reading the K3 Utility Helpfiles shows that it might be a problem that my
USB to serial connection is
via my Microkeyer2 and the recommendation is to change the cabling so that
the PC is
connected directly to the K3 and that cable does not fit the K3 RS232 port.
I suppose I will have to order the KUSB-cable from Elecraft.
Any other suggestions?
Kurt/SM6BGG

----- Original Message -----
From: "Jim Rogers" <[hidden email]>
To: "Kurt Wiksten" <[hidden email]>
Sent: Thursday, August 14, 2014 7:43 PM
Subject: Re: [Elecraft] Problems with K3 firmware update

> Kurt,
>
> Remember the K3 is basically an SDR and has a computer heart. Make sure
> you have power to the K3. Don't worry about the power switch on the
> front panel, it is not operational until the firmware is in place. The
> flashing TX LED is a good sign, it says the K3 is awaiting the firmware.
> Verify your connections for the firmware upload to the K3 and retry it.
> Once you get the firmware back into the K3, the front panel power switch
> will work again and all will be well.
>
> Jim, W4ATK
>
> On 8/14/2014 12:01 PM, Kurt Wiksten wrote:
>> I was trying to load new firmware to my K3. Present MCU version 04.51.
>> When started I got some Err message and the Tx lamp blinked and the K3
>> screen darkend. I tryed to
>> switch the power off on the K3 but it did not work so I paniced and
>> switched the power supply off.
>> I have tryed to switch the power on again but it is not possible.
>> What do I do?? Please help!
>> Kurt/SM6BGG
>>
>> --
>> I am using the free version of SPAMfighter.
>> SPAMfighter has removed 3975 of my spam emails to date.
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k6dgw

Re: Problems with K3 firmware update

Hi Kurt,

I don't have a Microkeyer but I distinctly remember some list traffic
some time back warning, "Don't try to update firmware through a
Microkeyer." If you look at the block diagram on the Microham web site,
the CAT interface comes from the internal CPU in the Microkeyer.
Assuming my memory is at least partially still intact, I believe that
was the problem, the firmware in the Microkeyer interferes with the K3
handshaking with the K3 Utility during FW loads.

What are your connectors? The K3 is a 2 row female DB9 if I remember
right [it's buried back in the non-wireless part of my station and its
very dark back there]

You can probably get a USB-RS232 adapter locally cheaper than paying
shipping costs. The Elecraft adapter I have uses the Prolific chip set
and runs fine. Some say the FTDI chip set is more reliable.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2014 Cal QSO Party 4-5 Oct 2014
- www.cqp.org

On 8/14/2014 4:02 PM, Kurt Wiksten wrote:
> Thanks to everybody for your advice.
> But my problem still not solved, because I am communicating with the K3
> via my Microkeyer2.

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Don Wilhelm-4

Re: Problems with K3 firmware update

In reply to this post by Kurt Wiksten

Kurt,

Both Microham and Elecraft warn that one should not attempt firmware
downloads through the MicroHam device. Other K3Utility functions work
fine through the Microham device.

If you have a real serial port on the computer, that is the preferred
connection, otherwise a good USB to serial adapter is the best answer.
The preferred adapter is one using an FTDI chip. Others may work (and I
can also recommend EdgePort).

BTW - there are counterfeit FTDI and Prolific USB to serial adapters on
the market. Both Prolific and FTDI have created new drivers for Windows
7 and above that detect those counterfeits and render them unusable - so
steer clear of bargain priced adapters whose instructions tell you to
turn off Windows updates and run their 'special' drivers.

The Elecraft KUSB cable uses an authentic FTDI chip. I have also had
success with a Keyspan adapter that was supplied for testing by a customer.

73,
Don W3FPR

On 8/14/2014 7:02 PM, Kurt Wiksten wrote:

> Thanks to everybody for your advice.
> But my problem still not solved, because I am communicating with the
> K3 via my Microkeyer2.
> Reading the K3 Utility Helpfiles shows that it might be a problem that
> my USB to serial connection is
> via my Microkeyer2 and the recommendation is to change the cabling so
> that the PC is
> connected directly to the K3 and that cable does not fit the K3 RS232
> port.
> I suppose I will have to order the KUSB-cable from Elecraft.

Joe Subich, W4TV-4

Re: Problems with K3 firmware update

Every microHAM Users Manual includes a specific warning *NOT* to
upload *any* transceiver firmware via the microHAM device. The
microHAM device constantly polls the transceiver for frequency and
mode. Those polls are not compatible with firmware uploads.

73,

... Joe, W4TV

On 2014-08-14 7:30 PM, Don Wilhelm wrote:

> Kurt,
>
> Both Microham and Elecraft warn that one should not attempt firmware
> downloads through the MicroHam device. Other K3Utility functions work
> fine through the Microham device.
>
> If you have a real serial port on the computer, that is the preferred
> connection, otherwise a good USB to serial adapter is the best answer.
> The preferred adapter is one using an FTDI chip. Others may work (and I
> can also recommend EdgePort).
>
> BTW - there are counterfeit FTDI and Prolific USB to serial adapters on
> the market. Both Prolific and FTDI have created new drivers for Windows
> 7 and above that detect those counterfeits and render them unusable - so
> steer clear of bargain priced adapters whose instructions tell you to
> turn off Windows updates and run their 'special' drivers.
>
> The Elecraft KUSB cable uses an authentic FTDI chip. I have also had
> success with a Keyspan adapter that was supplied for testing by a customer.
>
> 73,
> Don W3FPR
>
> On 8/14/2014 7:02 PM, Kurt Wiksten wrote:
>> Thanks to everybody for your advice.
>> But my problem still not solved, because I am communicating with the
>> K3 via my Microkeyer2.
>> Reading the K3 Utility Helpfiles shows that it might be a problem that
>> my USB to serial connection is
>> via my Microkeyer2 and the recommendation is to change the cabling so
>> that the PC is
>> connected directly to the K3 and that cable does not fit the K3 RS232
>> port.
>> I suppose I will have to order the KUSB-cable from Elecraft.
>
> ______________________________________________________________
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>

N7US

Re: Problems with K3 firmware update

I connected an A/B switchbox to switch the radio between the MKII and a
serial port on the computer (or an Edgeport US/serial box). It has been
easy to switch the K3/P3 to the serial port for firmware updates.

73, Jim N7US

-----Original Message-----

Every microHAM Users Manual includes a specific warning *NOT* to upload
*any* transceiver firmware via the microHAM device. The microHAM device
constantly polls the transceiver for frequency and mode. Those polls are
not compatible with firmware uploads.

73,

... Joe, W4TV

On 2014-08-14 7:30 PM, Don Wilhelm wrote:

customer.

>
> 73,
> Don W3FPR
>
> On 8/14/2014 7:02 PM, Kurt Wiksten wrote:
>> Thanks to everybody for your advice.
>> But my problem still not solved, because I am communicating with the
>> K3 via my Microkeyer2.
>> Reading the K3 Utility Helpfiles shows that it might be a problem
>> that my USB to serial connection is via my Microkeyer2 and the
>> recommendation is to change the cabling so that the PC is connected
>> directly to the K3 and that cable does not fit the K3 RS232 port.
>> I suppose I will have to order the KUSB-cable from Elecraft.

Joe Subich, W4TV-4

Re: Problems with K3 firmware update

On 2014-08-14 9:00 PM, Jim N7US wrote:
> I connected an A/B switchbox to switch the radio between the MKII and
> a serial port on the computer (or an Edgeport US/serial box).

As did I ... COM1 on the motherboard goes to a 4 port switch. Two of
the ports go to two ports switches on each K3/P3. The third port goes
to the cable for the XG3 and the fourth port goes to a AA5AU style
CW/PTT/FSK interface for general testing.

73,

... Joe, W4TV

On 2014-08-14 9:00 PM, Jim N7US wrote:

> I connected an A/B switchbox to switch the radio between the MKII and a
> serial port on the computer (or an Edgeport US/serial box). It has been
> easy to switch the K3/P3 to the serial port for firmware updates.
>
> 73, Jim N7US
>
>
>
> -----Original Message-----
>
> Every microHAM Users Manual includes a specific warning *NOT* to upload
> *any* transceiver firmware via the microHAM device. The microHAM device
> constantly polls the transceiver for frequency and mode. Those polls are
> not compatible with firmware uploads.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 2014-08-14 7:30 PM, Don Wilhelm wrote:
>> Kurt,
>>
>> Both Microham and Elecraft warn that one should not attempt firmware
>> downloads through the MicroHam device. Other K3Utility functions work
>> fine through the Microham device.
>>
>> If you have a real serial port on the computer, that is the preferred
>> connection, otherwise a good USB to serial adapter is the best answer.
>> The preferred adapter is one using an FTDI chip. Others may work (and
>> I can also recommend EdgePort).
>>
>> BTW - there are counterfeit FTDI and Prolific USB to serial adapters
>> on the market. Both Prolific and FTDI have created new drivers for
>> Windows
>> 7 and above that detect those counterfeits and render them unusable -
>> so steer clear of bargain priced adapters whose instructions tell you
>> to turn off Windows updates and run their 'special' drivers.
>>
>> The Elecraft KUSB cable uses an authentic FTDI chip. I have also had
>> success with a Keyspan adapter that was supplied for testing by a
> customer.
>>
>> 73,
>> Don W3FPR
>>
>> On 8/14/2014 7:02 PM, Kurt Wiksten wrote:
>>> Thanks to everybody for your advice.
>>> But my problem still not solved, because I am communicating with the
>>> K3 via my Microkeyer2.
>>> Reading the K3 Utility Helpfiles shows that it might be a problem
>>> that my USB to serial connection is via my Microkeyer2 and the
>>> recommendation is to change the cabling so that the PC is connected
>>> directly to the K3 and that cable does not fit the K3 RS232 port.
>>> I suppose I will have to order the KUSB-cable from Elecraft.
>
>
>
>
> ______________________________________________________________
> 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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>

KY7K

Re: Problems with K3 firmware update

In reply to this post by N7US

I did the same. Check thrift stores for a RS-232 switch if you don’t already have one. I picked mine for 25 cents at the local thrift store.
scl

>
> On 2014-08-14 9:00 PM, Jim N7US wrote:
>> I connected an A/B switchbox to switch the radio between the MKII and a
>> serial port on the computer (or an Edgeport US/serial box). It has been
>> easy to switch the K3/P3 to the serial port for firmware updates.
>>
>> 73, Jim N7US
>>
>>
>>
>> -----Original Message-----
>>
>> Every microHAM Users Manual includes a specific warning *NOT* to upload
>> *any* transceiver firmware via the microHAM device. The microHAM device
>> constantly polls the transceiver for frequency and mode. Those polls are
>> not compatible with firmware uploads.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>> On 2014-08-14 7:30 PM, Don Wilhelm wrote:
>>> Kurt,
>>>
>>> Both Microham and Elecraft warn that one should not attempt firmware
>>> downloads through the MicroHam device. Other K3Utility functions work
>>> fine through the Microham device.
>>>
>>> If you have a real serial port on the computer, that is the preferred
>>> connection, otherwise a good USB to serial adapter is the best answer.
>>> The preferred adapter is one using an FTDI chip. Others may work (and
>>> I can also recommend EdgePort).
>>>
>>> BTW - there are counterfeit FTDI and Prolific USB to serial adapters
>>> on the market. Both Prolific and FTDI have created new drivers for
>>> Windows
>>> 7 and above that detect those counterfeits and render them unusable -
>>> so steer clear of bargain priced adapters whose instructions tell you
>>> to turn off Windows updates and run their 'special' drivers.
>>>
>>> The Elecraft KUSB cable uses an authentic FTDI chip. I have also had
>>> success with a Keyspan adapter that was supplied for testing by a
>> customer.
>>>
>>> 73,
>>> Don W3FPR
>>>
>>> On 8/14/2014 7:02 PM, Kurt Wiksten wrote:
>>>> Thanks to everybody for your advice.
>>>> But my problem still not solved, because I am communicating with the
>>>> K3 via my Microkeyer2.
>>>> Reading the K3 Utility Helpfiles shows that it might be a problem
>>>> that my USB to serial connection is via my Microkeyer2 and the
>>>> recommendation is to change the cabling so that the PC is connected
>>>> directly to the K3 and that cable does not fit the K3 RS232 port.
>>>> I suppose I will have to order the KUSB-cable from Elecraft.
>>
>>
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
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>>
> ______________________________________________________________
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Steve - KY7K
[hidden email]
Get OUT and play radio!

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Arlen Fletcher

[KX3] KX3 Supply Voltage reading low

Greetings all!

My KX3 has the set of internal NiMH batteries and currently reads 9.9v while idling (I haven’t charged the batteries recently). When I power the KX3 from an external 12V SLA battery - which reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling. I might expect the KX3 to report slightly less than 12.2V if there is a diode on the supply input (I haven’t checked the schematics), but 2V seems like a significant difference. I’d welcome any feedback from the list on this issue.

Thanks!

73, Arlen - AA7F
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Elecraft mailing list

Re: [KX3] KX3 Supply Voltage reading low

Re: …reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling.

Arlen,

My first thoughts are that you need to fully charge the battery. I don’t have a lot of experience with lead acid batteries, though.

The input diode (CMS04 if my memory is correct) should only account for about 0.2v at KX3 receive current levels. I haven't looked at the schematic for a long time, so I can’t remember what else is in the path from the connector to where the internal voltage reading is measured, but I seem to recall at least one FET (on/off switch) and a current sensor.

The 12.2v is getting pretty close to the no-load fully discharged 1.95v per cell, and the 10.2v is pretty close to the 1.75v per cell of a fully discharged SLA battery. At these voltages, the discharge curves are getting pretty steep, so the addition of the KX3 receive current could cause the extra drop you are seeing.

Of course the problem could also lie in the power cable, connectors, or even inside the SLA battery itself. A check with a fresh, fully charged SLA battery will help isolate the problem. You will see voltage drop along the cable, even with a freshly charged battery, but 2 volts total sounds a bit high. I just pulled out an SLA that I haven’t used for a while, but it has been charged recently, and the voltage difference between the battery voltage (no load read by a cheap DMM) and the KX3 display (while in receive) was less than 1 volt.

Hope this helps.

Mark
KE6BB
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GM4JJJ

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by Arlen Fletcher

Arlen,

I wonder if what you are seeing on the display is the internal battery pack voltage rather than the external power supply voltage, either are selectable from the menu. The internal pack may increase slightly when the load is removed if you are running from external batteries.

Sorry if as we say over here if "I am teaching my grandmother how to suck eggs" :-)

73

David Anderson GM4JJJ

> On 15 Aug 2014, at 17:34, Arlen Fletcher <[hidden email]> wrote:
>
>
> Greetings all!
>
> My KX3 has the set of internal NiMH batteries and currently reads 9.9v while idling (I haven’t charged the batteries recently). When I power the KX3 from an external 12V SLA battery - which reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling. I might expect the KX3 to report slightly less than 12.2V if there is a diode on the supply input (I haven’t checked the schematics), but 2V seems like a significant difference. I’d welcome any feedback from the list on this issue.
>
> Thanks!
>
> 73, Arlen - AA7F
> ______________________________________________________________
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Arlen Fletcher

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by Elecraft mailing list

Hi Mark,

Thanks for the response!

I’m guessing that perhaps you’re considering that the voltage of the SLA is sagging when it’s running the KX3. I wondered that too - so I measured across the terminals of the SLA while it was powering the KX3. It still measured 12.2V, so it wasn’t sagging. The battery (and it’s little charger) report it as being fully charged - though I’m dubious about the accuracy of the little wall-wart charger. :-)

Arlen
AA7F

On Aug 15, 2014, at 11:42 AM, [hidden email] wrote:

> Re: …reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling.
>
> Arlen,
>
> My first thoughts are that you need to fully charge the battery. I don’t have a lot of experience with lead acid batteries, though.
>
> The input diode (CMS04 if my memory is correct) should only account for about 0.2v at KX3 receive current levels. I haven't looked at the schematic for a long time, so I can’t remember what else is in the path from the connector to where the internal voltage reading is measured, but I seem to recall at least one FET (on/off switch) and a current sensor.
>
> The 12.2v is getting pretty close to the no-load fully discharged 1.95v per cell, and the 10.2v is pretty close to the 1.75v per cell of a fully discharged SLA battery. At these voltages, the discharge curves are getting pretty steep, so the addition of the KX3 receive current could cause the extra drop you are seeing.
>
> Of course the problem could also lie in the power cable, connectors, or even inside the SLA battery itself. A check with a fresh, fully charged SLA battery will help isolate the problem. You will see voltage drop along the cable, even with a freshly charged battery, but 2 volts total sounds a bit high. I just pulled out an SLA that I haven’t used for a while, but it has been charged recently, and the voltage difference between the battery voltage (no load read by a cheap DMM) and the KX3 display (while in receive) was less than 1 volt.
>
> Hope this helps.
>
> Mark
> KE6BB

Arlen Fletcher

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by GM4JJJ

David,

I wasn’t aware of the ability to choose which supply (internal Vs. external) was being reported! Thanks for bringing that to my attention. I’ll bet you’re exactly right - that the internal battery voltage rises a bit when external power is supplied. I’ll check this out as soon as I get home this evening.

73

Arlen, AA7F

On Aug 15, 2014, at 12:53 PM, David Anderson <[hidden email]> wrote:

> Arlen,
>
> I wonder if what you are seeing on the display is the internal battery pack voltage rather than the external power supply voltage, either are selectable from the menu. The internal pack may increase slightly when the load is removed if you are running from external batteries.
>
> Sorry if as we say over here if "I am teaching my grandmother how to suck eggs" :-)
>
> 73
>
> David Anderson GM4JJJ
>
>> On 15 Aug 2014, at 17:34, Arlen Fletcher <[hidden email]> wrote:
>>
>>
>> Greetings all!
>>
>> My KX3 has the set of internal NiMH batteries and currently reads 9.9v while idling (I haven’t charged the batteries recently). When I power the KX3 from an external 12V SLA battery - which reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling. I might expect the KX3 to report slightly less than 12.2V if there is a diode on the supply input (I haven’t checked the schematics), but 2V seems like a significant difference. I’d welcome any feedback from the list on this issue.
>>
>> Thanks!
>>
>> 73, Arlen - AA7F
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Don Wilhelm-4

Re: [KX3] KX3 Supply Voltage reading low

Arlen,

As far as I know, there is no selection for observing the battery
voltage vs. the external voltage. The displayed voltage should be the
higher of the internal batteries or the external batteries. There is a
diode drop, so expect a reduction of 0.3 volts from the measurement at
the battery.

I suspect that the battery charger is dragging down the voltage from
your SLA battery (inside the KX3).
As another guess, the cable from the battery to the KX3 may be suffering
from poor connections that are causing a significant voltage drop by the
time the voltage reaches the KX3. It would be nice (and informative) to
measure the voltage at the K3 end of the power cable with your DMM (with
the KX3 turned on).

Is this an older KX3 or a relatively new one? The reason I ask is
because the early KX3s did not glue the power connector to the PC board
and could cause a separation of the connector voltage to the KX3 board.
That can also result in a high resistance where the connector is
soldered to the board (and produce a significant voltage drop.

I would suggest that you remove one or more of the batteries and see
what the voltage reading from the external battery may be. That will
eliminate any concern that the voltage of the internal batteries is
'dragging down' the voltage from the external supply.

I would also recommend that you use an external 13.8 volt supply rated
at 5 or 6 amps if you can to see what the voltage reading results might
be. A fully charged SLA battery showing 12.2 volts open circuit is not
fully charged, and the internal resistance of the partially discharged
battery may be giving you confusing measurements.

73,
Don W3FPR

On 8/15/2014 6:12 PM, Arlen Fletcher wrote:
> David,
>
> I wasn’t aware of the ability to choose which supply (internal Vs. external) was being reported! Thanks for bringing that to my attention. I’ll bet you’re exactly right - that the internal battery voltage rises a bit when external power is supplied. I’ll check this out as soon as I get home this evening.
>
>

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Don Wilhelm-4

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by Arlen Fletcher

Arlen,

I just measured the terminal voltage of several SLA and AGM batteries.
After not being charged for over a week, they all measured in excess of
13 volts. So my conclusion is that your wall-wart charger is not fully
charging your battery.
A normal float charge for an SLA battery should be at 13.8 volts - and
even that is not perfect because the best charging voltage varies with
temperature. A good 3 stage charger designed for charging SLA batteries
is the best to use, and those are a bit more expensive than the
"wall-wart" chargers, but worthwhile if you consider the life of your
SLA batteries important.

73,
Don W3FPR

On 8/15/2014 6:03 PM, Arlen Fletcher wrote:

> Hi Mark,
>
> Thanks for the response!
>
> I’m guessing that perhaps you’re considering that the voltage of the SLA is sagging when it’s running the KX3. I wondered that too - so I measured across the terminals of the SLA while it was powering the KX3. It still measured 12.2V, so it wasn’t sagging. The battery (and it’s little charger) report it as being fully charged - though I’m dubious about the accuracy of the little wall-wart charger. :-)
>
> Arlen
> AA7F
>
> On Aug 15, 2014, at 11:42 AM, [hidden email] wrote:
>
>> Re: …reads 12.2V on my Fluke DMM - the KX3 reports 10.2V while idling.
>>
>> Arlen,
>>
>> My first thoughts are that you need to fully charge the battery. I don’t have a lot of experience with lead acid batteries, though.
>>
>> The input diode (CMS04 if my memory is correct) should only account for about 0.2v at KX3 receive current levels. I haven't looked at the schematic for a long time, so I can’t remember what else is in the path from the connector to where the internal voltage reading is measured, but I seem to recall at least one FET (on/off switch) and a current sensor.
>>
>> The 12.2v is getting pretty close to the no-load fully discharged 1.95v per cell, and the 10.2v is pretty close to the 1.75v per cell of a fully discharged SLA battery. At these voltages, the discharge curves are getting pretty steep, so the addition of the KX3 receive current could cause the extra drop you are seeing.
>>
>> Of course the problem could also lie in the power cable, connectors, or even inside the SLA battery itself. A check with a fresh, fully charged SLA battery will help isolate the problem. You will see voltage drop along the cable, even with a freshly charged battery, but 2 volts total sounds a bit high. I just pulled out an SLA that I haven’t used for a while, but it has been charged recently, and the voltage difference between the battery voltage (no load read by a cheap DMM) and the KX3 display (while in receive) was less than 1 volt.
>>
>> Hope this helps.
>>
>> Mark
>> KE6BB
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GM4JJJ

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by Don Wilhelm-4

Don & Arlen,

Yes it has two voltage monitoring settings, PS and then BT.
I have a power supply connected, PS is 14.2V and BT is 10.5V
I disconnect power supply and PS is 10.0V and BT is 10.0V

Hope that clarifies.

73

David Anderson GM4JJJ

> On 16 Aug 2014, at 00:38, Don Wilhelm <[hidden email]> wrote:
>
>
> As far as I know, there is no selection for observing the battery voltage vs. the external voltage. The displayed voltage should be the higher of the internal batteries or the external batteries. There is a diode drop, so expect a reduction of 0.3 volts from the measurement at the battery.
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GM4JJJ

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by Don Wilhelm-4

Arlen Fletcher

Re: [KX3] KX3 Supply Voltage reading low

In reply to this post by GM4JJJ

Thanks Don and David for spending all the CPU cycles on my problem! It turns out the 2V drop was due to operator impedance - or a loose nut behind the controls, etc., etc. I was indeed monitoring the internal battery voltage instead of the external battery. {heavy sigh} So, now I’ll go back to my shack and ponder my ignorance for awhile.

Thanks again to everyone that took time to read and/or respond.

73

Arlen, AA7F

On Aug 16, 2014, at 12:25 PM, David Anderson <[hidden email]> wrote:

> Don & Arlen,
>
> Yes it has two voltage monitoring settings, PS and then BT.
> I have a power supply connected, PS is 14.2V and BT is 10.5V
> I disconnect power supply and PS is 10.0V and BT is 10.0V
>
> Hope that clarifies.
>
> 73
>
> David Anderson GM4JJJ
>
>> On 16 Aug 2014, at 00:38, Don Wilhelm <[hidden email]> wrote:
>>
>>
>> As far as I know, there is no selection for observing the battery voltage vs. the external voltage. The displayed voltage should be the higher of the internal batteries or the external batteries. There is a diode drop, so expect a reduction of 0.3 volts from the measurement at the battery.