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Battery requirements for NPOTA activation with KX3/KXPA100

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Esquer Dave

Battery requirements for NPOTA activation with KX3/KXPA100

Hi folks,
I know this has been asked and discussed before but I can’t seem to get a handle on a clear-cut answer …

I am going to do a SSB NPOTA (National Parks on the Air) activation with my KX3/KXPA100/PX3 on battery power. It has been in the works for a while with a special use permit required by the NPS.

How much battery capacity do I need if I want to run full 100 watts? For planning purposes, I am assuming a 6 hour activation with a (highly optimistic I know) 60 QSOs per hour.

The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do just fine. My concern is the amount of draw I will need to last the 6 hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a QSO. The QSOs varies between 50-80 watts on transmit.

I also know that once I am spotted, I can drop the power down to maybe 75-50 watts to save some battery juice.

I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered? If you have any real-world experience or tips, it is most valuable and appreciated. You can contact me offline at dave dot esquer AT gmail as well.

Thanks,
Dave, K6WDE

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Nr4c

Re: Battery requirements for NPOTA activation with KX3/KXPA100

I think you'll draw a lot more than 8A at 100 watts.

Also note that to get 100 watts from this setup will require a bit more than 14 volts I think. I ran my PS at 14.5 or better to make it. YMMV!

You're gonna get a lot responses on this query, so be prepared.

Your best friend here is going to be AMPHOURS. The more you have the longer you'll be able to keep the voltage drop down. When the voltage drops too low the KX3 will drop the power. You might consider starting st 75 watts and drop a bit when the pileup gets going.

Where at you going. And have your spotters note the park or Unit ID.

Sent from my iPhone
...nr4c. bill

> On Mar 29, 2016, at 4:41 PM, Esquer Dave <[hidden email]> wrote:
>
> Hi folks,
> I know this has been asked and discussed before but I can’t seem to get a handle on a clear-cut answer …
>
> I am going to do a SSB NPOTA (National Parks on the Air) activation with my KX3/KXPA100/PX3 on battery power. It has been in the works for a while with a special use permit required by the NPS.
>
> How much battery capacity do I need if I want to run full 100 watts? For planning purposes, I am assuming a 6 hour activation with a (highly optimistic I know) 60 QSOs per hour.
>
> The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do just fine. My concern is the amount of draw I will need to last the 6 hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a QSO. The QSOs varies between 50-80 watts on transmit.
>
> I also know that once I am spotted, I can drop the power down to maybe 75-50 watts to save some battery juice.
>
> I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered? If you have any real-world experience or tips, it is most valuable and appreciated. You can contact me offline at dave dot esquer AT gmail as well.
>
> Thanks,
> Dave, K6WDE
>
>
>
>
>
> ______________________________________________________________
> 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]

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Fred Townsend-2

Re: Battery requirements for NPOTA activation with KX3/KXPA100

In reply to this post by Esquer Dave

Councilor: LOL if you are looking for precise information from imprecise data. Best I can do is a WAG. If you take your ah rating say 36 and multiply by the battery voltage say 12, we have 432 watt hours. Divide by 2 to account for efficiency losses and we have 216 wH and finally divide by your transmit draw 80 watts and we have 2.7 transmit hours. Does this help? Remember this is a WAG (Wild Assed Guess).
73
Fred, AE6QL

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Esquer Dave
Sent: Tuesday, March 29, 2016 1:42 PM
To: [hidden email]
Subject: [Elecraft] Battery requirements for NPOTA activation with KX3/KXPA100

Hi folks,
I know this has been asked and discussed before but I can’t seem to get a handle on a clear-cut answer …

I am going to do a SSB NPOTA (National Parks on the Air) activation with my KX3/KXPA100/PX3 on battery power. It has been in the works for a while with a special use permit required by the NPS.

How much battery capacity do I need if I want to run full 100 watts? For planning purposes, I am assuming a 6 hour activation with a (highly optimistic I know) 60 QSOs per hour.

The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do just fine. My concern is the amount of draw I will need to last the 6 hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a QSO. The QSOs varies between 50-80 watts on transmit.

I also know that once I am spotted, I can drop the power down to maybe 75-50 watts to save some battery juice.

I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered? If you have any real-world experience or tips, it is most valuable and appreciated. You can contact me offline at dave dot esquer AT gmail as well.

Thanks,
Dave, K6WDE

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lstavenhagen

Re: Battery requirements for NPOTA activation with KX3/KXPA100

In reply to this post by Esquer Dave

I've looked at this too, given that I'm /P almost 100% of the time now and have considered various QRO options. Unfortunately, I've yet to find a QRO solution that doesn't involve something semi-permanently mounted in my truck. Either a deep-cycle AGM or a high capacity LiFEPO4 in the spare battery tray under the hood with long heavy cables is about the best I've been able to come up with.

If I keep it at 10 watts or less, though, I can actually carry it a short distance (and of course its easily transportable in the vehicle). My K3 and K3S, for instance, will run a good 4 or 5 hours on my 9AH AGM batt, though less than that with a lot of transmitting. The K2 would run all day on the same batt....

So that might be required in your case too? Eg. a YellowTop 12V deep cycle in the vehicle or an equivalent LiFE 12V... Sorry, I know that's not much help, but I'm kind of in the same boat hi hi.

73,
LS
W5QD

Grant Youngman

Re: Battery requirements for NPOTA activation with KX3/KXPA100

In reply to this post by Fred Townsend-2

SSB is low duty cycle. Even if you have processing cranked way up, with 80 watts out peak, your average power won't be any where near this level. And you do have to stop talking and listen, fetch a beverage, visit the nearest shrubs, right? :)

I think you'd easily do 6 hours with what you have -- and have a good bit of battery left over.

Grant NQ5T

Sent from my iPhone

> and we have 216 wH and finally divide by your transmit draw 80 watts and we have 2.7 transmit hours.

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Igor Sokolov-2

Re: Battery requirements for NPOTA activation withKX3/KXPA100

In reply to this post by Esquer Dave

I have experimented with LiFePo4 batteries feeding KX3/KXPA100 in contest
environment where duty cycle is about 50% for TX. For SSB the current draw
is a bit higher then for CW. 25Ah battery lasted 4 to 4.5 hour with 100 W in
the beginning and dropping to 50-60W out in the end of the cycle. For SLA of
the same capacity you will probably have half of that time. With 2x 60W
solar panels added to the mix I get between 6 to 8 hours in semi sunny
weather. I have ended up with a pair of LiFePo4 25Ah each (about 2 Kg each)
which allow full day of operation. Again if you use SLA instead of LiFePo4
you will need at least 100 Ah.

73, Igor UA9CDC

----- Original Message -----
From: "Esquer Dave" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, March 30, 2016 1:41 AM
Subject: [Elecraft] Battery requirements for NPOTA activation
withKX3/KXPA100

> Hi folks,
> I know this has been asked and discussed before but I can’t seem to get a
> handle on a clear-cut answer …
>
> I am going to do a SSB NPOTA (National Parks on the Air) activation with
> my KX3/KXPA100/PX3 on battery power. It has been in the works for a while
> with a special use permit required by the NPS.
>
> How much battery capacity do I need if I want to run full 100 watts? For
> planning purposes, I am assuming a 6 hour activation with a (highly
> optimistic I know) 60 QSOs per hour.
>
> The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do
> just fine. My concern is the amount of draw I will need to last the 6
> hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max
> current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a
> QSO. The QSOs varies between 50-80 watts on transmit.
>
> I also know that once I am spotted, I can drop the power down to maybe
> 75-50 watts to save some battery juice.
>
> I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered?
> If you have any real-world experience or tips, it is most valuable and
> appreciated. You can contact me offline at dave dot esquer AT gmail as
> well.
>
> Thanks,
> Dave, K6WDE
>
>
>
>
>
> ______________________________________________________________
> 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]

Igor Sokolov-2

Operating temperature range ( second attempt)

In reply to this post by Grant Youngman

There were no responce to the initial message so I post it again:

I have both K3 and KX3 and I sometimes use them outside in a field
operation. Here in Russia we have one funny QRP contest called "Frost-red
nose" where extra points are given for low temperature environment during
field operation. The contest happens in January when in some places
temperatures can be down to minus 30 C. I did not find temperature
requirements for K3/KX3 in the specs. Can somebody give me a hint or may be
share own experience. What would be the lowest temperature where the rig
will still perform adequately?

73, Igor UA9CDC

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Robert Nobis - N7RJN

Re: Operating temperature range ( second attempt)

You should directly contact the Elecraft factory for this. However, as I recall, the K3 and KX3 are designed to operate over an operating temperature rating: 0 – 50 °C.

73,

Bob Nobis - N7RJN
[hidden email]

> On Mar 29, 2016, at 21:20, Igor Sokolov <[hidden email]> wrote:
>
> There were no responce to the initial message so I post it again:
>
> I have both K3 and KX3 and I sometimes use them outside in a field
> operation. Here in Russia we have one funny QRP contest called "Frost-red
> nose" where extra points are given for low temperature environment during
> field operation. The contest happens in January when in some places
> temperatures can be down to minus 30 C. I did not find temperature
> requirements for K3/KX3 in the specs. Can somebody give me a hint or may be
> share own experience. What would be the lowest temperature where the rig
> will still perform adequately?
>
> 73, Igor UA9CDC
>
> ______________________________________________________________
> 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]
>

kevinr@coho.net

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

This may not be applicable to the K3 but I have used the K2 below 32 F.
My K2 has the 100 watt amp with a built in fan. The fan got confused
and stayed on. The algorithm to adjust the fan speed did not understand
a negative Celsius temperature. With the fan blowing my fingers got
pretty numb and kept sending more dits than desired :)
73,
Kevin. KD5ONS

On 3/29/2016 9:20 PM, Igor Sokolov wrote:

> There were no responce to the initial message so I post it again:
>
> I have both K3 and KX3 and I sometimes use them outside in a field
> operation. Here in Russia we have one funny QRP contest called "Frost-red
> nose" where extra points are given for low temperature environment during
> field operation. The contest happens in January when in some places
> temperatures can be down to minus 30 C. I did not find temperature
> requirements for K3/KX3 in the specs. Can somebody give me a hint or
> may be
> share own experience. What would be the lowest temperature where the rig
> will still perform adequately?
>
> 73, Igor UA9CDC
>
> ______________________________________________________________
> 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]
>

Brendon Whateley

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

Hi Igor,

I think that some have operated at low temperatures in some winter
competitions -- the US North East gets pretty darn cold -- similar to what
you are talking about. I looked and easily found similar questions to
yours, but no answers!

The two things I'd be concerned about are the batteries and any
electrolytic components that may be damaged by extreme low temperatures.
The LCD screen will also stop working at low temperature, but I've never
broken one by freezing -- but perhaps I was just lucky!

I think batteries will have issues before most of the electronics. I'd
suggest building a small insulated (expanded foam?) enclosure to hold the
radio and battery. You could then stick some chemical hand warmers into the
container and keep everything at a reasonable temperature. Look at how the
"space balloon" people do things, they may have some tips. Alternatively
keep the batteries in an inside pocket of your clothing.

An email to the Elecraft guys may give some guidelines for temperatures
that may damage components... but apart from those, I'd just give it a try!

Good luck and let us know what you find out, so that we can answer the
question next time it comes up. (I live in California at the moment and our
harsh winter temperatures barely touch freezing at night!)

- Brendon
KK6AYI

On Tue, Mar 29, 2016 at 9:20 PM, Igor Sokolov <[hidden email]> wrote:

> There were no responce to the initial message so I post it again:
>
> I have both K3 and KX3 and I sometimes use them outside in a field
> operation. Here in Russia we have one funny QRP contest called "Frost-red
> nose" where extra points are given for low temperature environment during
> field operation. The contest happens in January when in some places
> temperatures can be down to minus 30 C. I did not find temperature
> requirements for K3/KX3 in the specs. Can somebody give me a hint or may be
> share own experience. What would be the lowest temperature where the rig
> will still perform adequately?
>
> 73, Igor UA9CDC
>
> ______________________________________________________________
> 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]
>

Igor Sokolov-2

Re: Operating temperature range ( second attempt)

Thanks Brendon,Bob and Kevin. I am not worried about batteries. My LiFePo4
were tested at minus 20 C and the drop in capacity is insignificant. Looks
like nobody tested K3 or KX3 at below freezing temperatures so I will have
to be the first :) A bit scary...

73, Igor UA9CDC
----- Original Message -----
From: "Brendon Whateley" <[hidden email]>
To: "Igor Sokolov" <[hidden email]>
Cc: "Elecraft Reflector Reflector" <[hidden email]>
Sent: Wednesday, March 30, 2016 6:50 PM
Subject: Re: [Elecraft] Operating temperature range ( second attempt)

> Hi Igor,
>
> I think that some have operated at low temperatures in some winter
> competitions -- the US North East gets pretty darn cold -- similar to what
> you are talking about. I looked and easily found similar questions to
> yours, but no answers!
>
> The two things I'd be concerned about are the batteries and any
> electrolytic components that may be damaged by extreme low temperatures.
> The LCD screen will also stop working at low temperature, but I've never
> broken one by freezing -- but perhaps I was just lucky!
>
> I think batteries will have issues before most of the electronics. I'd
> suggest building a small insulated (expanded foam?) enclosure to hold the
> radio and battery. You could then stick some chemical hand warmers into
> the
> container and keep everything at a reasonable temperature. Look at how the
> "space balloon" people do things, they may have some tips. Alternatively
> keep the batteries in an inside pocket of your clothing.
>
> An email to the Elecraft guys may give some guidelines for temperatures
> that may damage components... but apart from those, I'd just give it a
> try!
>
> Good luck and let us know what you find out, so that we can answer the
> question next time it comes up. (I live in California at the moment and
> our
> harsh winter temperatures barely touch freezing at night!)
>
> - Brendon
> KK6AYI
>
> On Tue, Mar 29, 2016 at 9:20 PM, Igor Sokolov <[hidden email]> wrote:
>
>> There were no responce to the initial message so I post it again:
>>
>> I have both K3 and KX3 and I sometimes use them outside in a field
>> operation. Here in Russia we have one funny QRP contest called
>> "Frost-red
>> nose" where extra points are given for low temperature environment during
>> field operation. The contest happens in January when in some places
>> temperatures can be down to minus 30 C. I did not find temperature
>> requirements for K3/KX3 in the specs. Can somebody give me a hint or may
>> be
>> share own experience. What would be the lowest temperature where the rig
>> will still perform adequately?
>>
>> 73, Igor UA9CDC
>>
>> ______________________________________________________________
>> 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]
>>
>

N1EU

Re: Operating temperature range ( second attempt)

No, many of SOTA activators have used a KX3 below freezing. We just
haven't used one at -30C (-22F) like you originally mentioned.

73, Barry N1EU

On Wed, Mar 30, 2016 at 11:02 AM, Igor Sokolov <[hidden email]> wrote:

> Thanks Brendon,Bob and Kevin. I am not worried about batteries. My LiFePo4
> were tested at minus 20 C and the drop in capacity is insignificant. Looks
> like nobody tested K3 or KX3 at below freezing temperatures so I will have
> to be the first :) A bit scary...
>
> 73, Igor UA9CDC
> ----- Original Message ----- From: "Brendon Whateley" <
> [hidden email]>
> To: "Igor Sokolov" <[hidden email]>
> Cc: "Elecraft Reflector Reflector" <[hidden email]>
> Sent: Wednesday, March 30, 2016 6:50 PM
> Subject: Re: [Elecraft] Operating temperature range ( second attempt)
>
>
>
> Hi Igor,
>>
>> I think that some have operated at low temperatures in some winter
>> competitions -- the US North East gets pretty darn cold -- similar to what
>> you are talking about. I looked and easily found similar questions to
>> yours, but no answers!
>>
>> The two things I'd be concerned about are the batteries and any
>> electrolytic components that may be damaged by extreme low temperatures.
>> The LCD screen will also stop working at low temperature, but I've never
>> broken one by freezing -- but perhaps I was just lucky!
>>
>> I think batteries will have issues before most of the electronics. I'd
>> suggest building a small insulated (expanded foam?) enclosure to hold the
>> radio and battery. You could then stick some chemical hand warmers into
>> the
>> container and keep everything at a reasonable temperature. Look at how the
>> "space balloon" people do things, they may have some tips. Alternatively
>> keep the batteries in an inside pocket of your clothing.
>>
>> An email to the Elecraft guys may give some guidelines for temperatures
>> that may damage components... but apart from those, I'd just give it a
>> try!
>>
>> Good luck and let us know what you find out, so that we can answer the
>> question next time it comes up. (I live in California at the moment and
>> our
>> harsh winter temperatures barely touch freezing at night!)
>>
>> - Brendon
>> KK6AYI
>>
>> On Tue, Mar 29, 2016 at 9:20 PM, Igor Sokolov <[hidden email]> wrote:
>>
>> There were no responce to the initial message so I post it again:
>>>
>>> I have both K3 and KX3 and I sometimes use them outside in a field
>>> operation. Here in Russia we have one funny QRP contest called "Frost-red
>>> nose" where extra points are given for low temperature environment during
>>> field operation. The contest happens in January when in some places
>>> temperatures can be down to minus 30 C. I did not find temperature
>>> requirements for K3/KX3 in the specs. Can somebody give me a hint or may
>>> be
>>> share own experience. What would be the lowest temperature where the rig
>>> will still perform adequately?
>>>
>>> 73, Igor UA9CDC
>>>
>>> ______________________________________________________________
>>> 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]
>

Richard Fjeld-2

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

Hi Igor,

I live in Minnesota and our temps get down similar to yours. I have not
tried my
K3 in those temps, but I have had mobile rigs in early days of solid
state and when
first turned on, nothing would happen for a few minutes until they
warmed up.
Newer circuit designs may have changed that.

I would worry about the condensation that forms when the radio is
brought into the warmth again.

73, Dick, n0ce

On 3/29/2016 11:20 PM, Igor Sokolov wrote:
> There were no responce to the initial message so I post it again:
>
> I have both K3 and KX3 and I sometimes use them outside in a field
> operation.

______________________________________________________________
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Nels Anderson

Re: Battery requirements for NPOTA activation with KX3/KXPA100

In reply to this post by Esquer Dave

Having recently done several NPOTA activations I'll share my experience.
I have a non-Elecraft radio permanently mounted in my truck (my nice K3
station stays home), run about 100 watts into a typical screwdriver
antenna. I ran off the single battery in my truck, which is good for
about 50 to 60 amp hours (non-AGM battery).

In past years I've done contests where I hunt and pounce and have gone 4
or more hours without killing the battery. NPOTA is way different! The
last time I went out, not thinking about the duty cycle difference, I
operated about 2 to 2.5 hours and when I went to start the truck the
battery was dead. In that time I'd made 176 QSOs, so don't think that 60
QSOs per hour is optimistic...it's easily accomplished if conditions are
good. And that means you'll be transmitting a lot.

So, I killed a car battery in 2 or so hours. If you want to operate 6
hours you're going to need roughly the equivalent of 3 standard car
batteries. Not very scientific I know, but a reasonable estimate I think.

I'm now looking to install a second battery in the truck, as I want to
do more NPOTA activations...

73 Nels K1UR

On 3/29/2016 4:41 PM, Esquer Dave wrote:

> Hi folks,
> I know this has been asked and discussed before but I can’t seem to get a handle on a clear-cut answer …
>
> I am going to do a SSB NPOTA (National Parks on the Air) activation with my KX3/KXPA100/PX3 on battery power. It has been in the works for a while with a special use permit required by the NPS.
>
> How much battery capacity do I need if I want to run full 100 watts? For planning purposes, I am assuming a 6 hour activation with a (highly optimistic I know) 60 QSOs per hour.
>
> The PX3 will be powered by a separate LiFePo 4.8 aH battery, it will do just fine. My concern is the amount of draw I will need to last the 6 hours. With an inline (Hobby King) HK-010 Power Analyzer, I see a max current (KX3/KXPA100 combo) of about 8 amps and about 80 watts during a QSO. The QSOs varies between 50-80 watts on transmit.
>
> I also know that once I am spotted, I can drop the power down to maybe 75-50 watts to save some battery juice.
>
> I have 2 12v-18aH SLA batteries at the ready, am I woefully underpowered? If you have any real-world experience or tips, it is most valuable and appreciated. You can contact me offline at dave dot esquer AT gmail as well.
>
> Thanks,
> Dave, K6WDE
>
>
>
>
>
> ______________________________________________________________
> 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]

John Hendricks-2

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

I have operated my K1 (after cap modification by Elecraft) & KX1 at -
40 C & F with only my fingers suffering from the cold. When I did temp compensation on my KX3 I took it down to -10 C. I know KL7EDK in Fairbanks AK may operate on the Yukon Quest with a KX3 which gets very very cold.

John K7JLT

Igor Sokolov <[hidden email]> wrote:

>There were no responce to the initial message so I post it again:
>
>I have both K3 and KX3 and I sometimes use them outside in a field
>operation. Here in Russia we have one funny QRP contest called "Frost-red
>nose" where extra points are given for low temperature environment during
>field operation. The contest happens in January when in some places
>temperatures can be down to minus 30 C. I did not find temperature
>requirements for K3/KX3 in the specs. Can somebody give me a hint or may be
>share own experience. What would be the lowest temperature where the rig
>will still perform adequately?
>
>73, Igor UA9CDC
>
>______________________________________________________________
>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]

Igor Sokolov-2

Re: Operating temperature range ( second attempt)

In reply to this post by N1EU

Barry, what was the lowest temperature you have used your KX3 without
noticeable deterioration of performance?

73, Igor UA9CDC
----- Original Message -----
From: "Barry N1EU" <[hidden email]>
To: "Elecraft Reflector Reflector" <[hidden email]>
Sent: Wednesday, March 30, 2016 8:23 PM
Subject: Re: [Elecraft] Operating temperature range ( second attempt)

> No, many of SOTA activators have used a KX3 below freezing. We just
> haven't used one at -30C (-22F) like you originally mentioned.
>
> 73, Barry N1EU
>
> On Wed, Mar 30, 2016 at 11:02 AM, Igor Sokolov <[hidden email]> wrote:
>
>> Thanks Brendon,Bob and Kevin. I am not worried about batteries. My
>> LiFePo4
>> were tested at minus 20 C and the drop in capacity is insignificant.
>> Looks
>> like nobody tested K3 or KX3 at below freezing temperatures so I will
>> have
>> to be the first :) A bit scary...
>>
>> 73, Igor UA9CDC
>> ----- Original Message ----- From: "Brendon Whateley" <
>> [hidden email]>
>> To: "Igor Sokolov" <[hidden email]>
>> Cc: "Elecraft Reflector Reflector" <[hidden email]>
>> Sent: Wednesday, March 30, 2016 6:50 PM
>> Subject: Re: [Elecraft] Operating temperature range ( second attempt)
>>
>>
>>
>> Hi Igor,
>>>
>>> I think that some have operated at low temperatures in some winter
>>> competitions -- the US North East gets pretty darn cold -- similar to
>>> what
>>> you are talking about. I looked and easily found similar questions to
>>> yours, but no answers!
>>>
>>> The two things I'd be concerned about are the batteries and any
>>> electrolytic components that may be damaged by extreme low temperatures.
>>> The LCD screen will also stop working at low temperature, but I've never
>>> broken one by freezing -- but perhaps I was just lucky!
>>>
>>> I think batteries will have issues before most of the electronics. I'd
>>> suggest building a small insulated (expanded foam?) enclosure to hold
>>> the
>>> radio and battery. You could then stick some chemical hand warmers into
>>> the
>>> container and keep everything at a reasonable temperature. Look at how
>>> the
>>> "space balloon" people do things, they may have some tips. Alternatively
>>> keep the batteries in an inside pocket of your clothing.
>>>
>>> An email to the Elecraft guys may give some guidelines for temperatures
>>> that may damage components... but apart from those, I'd just give it a
>>> try!
>>>
>>> Good luck and let us know what you find out, so that we can answer the
>>> question next time it comes up. (I live in California at the moment and
>>> our
>>> harsh winter temperatures barely touch freezing at night!)
>>>
>>> - Brendon
>>> KK6AYI
>>>
>>> On Tue, Mar 29, 2016 at 9:20 PM, Igor Sokolov <[hidden email]> wrote:
>>>
>>> There were no responce to the initial message so I post it again:
>>>>
>>>> I have both K3 and KX3 and I sometimes use them outside in a field
>>>> operation. Here in Russia we have one funny QRP contest called
>>>> "Frost-red
>>>> nose" where extra points are given for low temperature environment
>>>> during
>>>> field operation. The contest happens in January when in some places
>>>> temperatures can be down to minus 30 C. I did not find temperature
>>>> requirements for K3/KX3 in the specs. Can somebody give me a hint or
>>>> may
>>>> be
>>>> share own experience. What would be the lowest temperature where the
>>>> rig
>>>> will still perform adequately?
>>>>
>>>> 73, Igor UA9CDC
>>>>
>>>> ______________________________________________________________
>>>> 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]
>>
> ______________________________________________________________
> 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]

Igor Sokolov-2

Re: Operating temperature range ( second attempt)

In reply to this post by Richard Fjeld-2

Thank you Dick. Condensation inside the rig is a known problem. I will sure
take care not to switch it on before it is dried out inside.

----- Original Message -----
From: "Richard Fjeld" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, March 30, 2016 8:26 PM
Subject: Re: [Elecraft] Operating temperature range ( second attempt)

> Hi Igor,
> I would worry about the condensation that forms when the radio is brought
> into the warmth again.
>
> 73, Dick, n0ce
>
> On 3/29/2016 11:20 PM, Igor Sokolov wrote:
>> There were no responce to the initial message so I post it again:
>>
>> I have both K3 and KX3 and I sometimes use them outside in a field
>> operation.
>
> ______________________________________________________________
> 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]

N1EU

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

The coldest I've operated is probably about 20F (-7C). I've never seen any
cold related issues with the KX3.

73, Barry N1EU

On Wed, Mar 30, 2016 at 12:38 PM, Igor Sokolov <[hidden email]> wrote:

> Barry, what was the lowest temperature you have used your KX3 without
> noticeable deterioration of performance?
>
> 73, Igor UA9CDC
> ----- Original Message ----- From: "Barry N1EU" <[hidden email]>
> To: "Elecraft Reflector Reflector" <[hidden email]>
> Sent: Wednesday, March 30, 2016 8:23 PM
> Subject: Re: [Elecraft] Operating temperature range ( second attempt)
>
>
> No, many of SOTA activators have used a KX3 below freezing. We just
>> haven't used one at -30C (-22F) like you originally mentioned.
>>
>> 73, Barry N1EU
>>
>> On Wed, Mar 30, 2016 at 11:02 AM, Igor Sokolov <[hidden email]> wrote:
>>
>> Thanks Brendon,Bob and Kevin. I am not worried about batteries. My LiFePo4
>>> were tested at minus 20 C and the drop in capacity is insignificant.
>>> Looks
>>> like nobody tested K3 or KX3 at below freezing temperatures so I will
>>> have
>>> to be the first :) A bit scary...
>>>
>>> 73, Igor UA9CDC
>>> ----- Original Message ----- From: "Brendon Whateley" <
>>> [hidden email]>
>>> To: "Igor Sokolov" <[hidden email]>
>>> Cc: "Elecraft Reflector Reflector" <[hidden email]>
>>> Sent: Wednesday, March 30, 2016 6:50 PM
>>> Subject: Re: [Elecraft] Operating temperature range ( second attempt)
>>>
>>>
>>>
>>> Hi Igor,
>>>
>>>>
>>>> I think that some have operated at low temperatures in some winter
>>>> competitions -- the US North East gets pretty darn cold -- similar to
>>>> what
>>>> you are talking about. I looked and easily found similar questions to
>>>> yours, but no answers!
>>>>
>>>> The two things I'd be concerned about are the batteries and any
>>>> electrolytic components that may be damaged by extreme low temperatures.
>>>> The LCD screen will also stop working at low temperature, but I've never
>>>> broken one by freezing -- but perhaps I was just lucky!
>>>>
>>>> I think batteries will have issues before most of the electronics. I'd
>>>> suggest building a small insulated (expanded foam?) enclosure to hold
>>>> the
>>>> radio and battery. You could then stick some chemical hand warmers into
>>>> the
>>>> container and keep everything at a reasonable temperature. Look at how
>>>> the
>>>> "space balloon" people do things, they may have some tips. Alternatively
>>>> keep the batteries in an inside pocket of your clothing.
>>>>
>>>> An email to the Elecraft guys may give some guidelines for temperatures
>>>> that may damage components... but apart from those, I'd just give it a
>>>> try!
>>>>
>>>> Good luck and let us know what you find out, so that we can answer the
>>>> question next time it comes up. (I live in California at the moment and
>>>> our
>>>> harsh winter temperatures barely touch freezing at night!)
>>>>
>>>> - Brendon
>>>> KK6AYI
>>>>
>>>> On Tue, Mar 29, 2016 at 9:20 PM, Igor Sokolov <[hidden email]> wrote:
>>>>
>>>> There were no responce to the initial message so I post it again:
>>>>
>>>>>
>>>>> I have both K3 and KX3 and I sometimes use them outside in a field
>>>>> operation. Here in Russia we have one funny QRP contest called
>>>>> "Frost-red
>>>>> nose" where extra points are given for low temperature environment
>>>>> during
>>>>> field operation. The contest happens in January when in some places
>>>>> temperatures can be down to minus 30 C. I did not find temperature
>>>>> requirements for K3/KX3 in the specs. Can somebody give me a hint or
>>>>> may
>>>>> be
>>>>> share own experience. What would be the lowest temperature where the
>>>>> rig
>>>>> will still perform adequately?
>>>>>
>>>>> 73, Igor UA9CDC
>>>>>
>>>>> ______________________________________________________________
>>>>> 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]
>>>
>>> ______________________________________________________________
>> 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]
>>
>
>

Igor Sokolov-2

Re: Operating temperature range ( second attempt)

In reply to this post by John Hendricks-2

Thanks Jerry. +8F (-13 C) is the lowest mentioned here so far for KX3. I
will have to wait till next winter to try temperatures lower then that. Now
it only gets down to minus 8C in the night and day temperatures are all
above freezing.

73, Igor UA9CDC
----- Original Message -----
From: "Jerry Curry" <[hidden email]>
To: "John K7JLT" <[hidden email]>
Cc: "Igor Sokolov" <[hidden email]>; "Mailman" <[hidden email]>
Sent: Wednesday, March 30, 2016 9:54 PM
Subject: Re: [Elecraft] Operating temperature range ( second attempt)

I’ve run my KX3 at +8F with no problems but that was SSB. I’ve not done any
temp compensation on it. Also,
the radio was ‘warm’ +60F when started but was outside in the cold at +8F
for about 5 hours. It may have generated enough heat internally to help and
I’m not sure if a cold soaked radio would operate the same from a cold
start. Great little radio!!

Jerry
KL7EDK

> On Mar 30, 2016, at 8:32 AM, John K7JLT <[hidden email]> wrote:
>
> I have operated my K1 (after cap modification by Elecraft) & KX1 at -
> 40 C & F with only my fingers suffering from the cold. When I did temp
> compensation on my KX3 I took it down to -10 C. I know KL7EDK in
> Fairbanks AK may operate on the Yukon Quest with a KX3 which gets very
> very cold.
>
> John K7JLT
>
> Igor Sokolov <[hidden email]> wrote:
>
>> There were no responce to the initial message so I post it again:
>>
>> I have both K3 and KX3 and I sometimes use them outside in a field
>> operation. Here in Russia we have one funny QRP contest called
>> "Frost-red
>> nose" where extra points are given for low temperature environment during
>> field operation. The contest happens in January when in some places
>> temperatures can be down to minus 30 C. I did not find temperature
>> requirements for K3/KX3 in the specs. Can somebody give me a hint or may
>> be
>> share own experience. What would be the lowest temperature where the rig
>> will still perform adequately?
>>
>> 73, Igor UA9CDC
>>
>> ______________________________________________________________
>> 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]

John Hendricks-2

Re: Operating temperature range ( second attempt)

In reply to this post by Igor Sokolov-2

When I did the temp compensation the radio had cold soaked over night. The only problem that I remember was a slow display. I ran the radio up to 110F, 43C (radio out in the sun).

John K7JLT

Igor Sokolov <[hidden email]> wrote:

>Thanks Jerry. +8F (-13 C) is the lowest mentioned here so far for KX3. I
>will have to wait till next winter to try temperatures lower then that. Now
>it only gets down to minus 8C in the night and day temperatures are all
>above freezing.
>
>73, Igor UA9CDC
>----- Original Message -----
>From: "Jerry Curry" <[hidden email]>
>To: "John K7JLT" <[hidden email]>
>Cc: "Igor Sokolov" <[hidden email]>; "Mailman" <[hidden email]>
>Sent: Wednesday, March 30, 2016 9:54 PM
>Subject: Re: [Elecraft] Operating temperature range ( second attempt)
>
>
>I’ve run my KX3 at +8F with no problems but that was SSB. I’ve not done any
>temp compensation on it. Also,
>the radio was ‘warm’ +60F when started but was outside in the cold at +8F
>for about 5 hours. It may have generated enough heat internally to help and
>I’m not sure if a cold soaked radio would operate the same from a cold
>start. Great little radio!!
>
>Jerry
>KL7EDK
>
>
>> On Mar 30, 2016, at 8:32 AM, John K7JLT <[hidden email]> wrote:
>>
>> I have operated my K1 (after cap modification by Elecraft) & KX1 at -
>> 40 C & F with only my fingers suffering from the cold. When I did temp
>> compensation on my KX3 I took it down to -10 C. I know KL7EDK in
>> Fairbanks AK may operate on the Yukon Quest with a KX3 which gets very
>> very cold.
>>
>> John K7JLT
>>
>> Igor Sokolov <[hidden email]> wrote:
>>
>>> There were no responce to the initial message so I post it again:
>>>
>>> I have both K3 and KX3 and I sometimes use them outside in a field
>>> operation. Here in Russia we have one funny QRP contest called
>>> "Frost-red
>>> nose" where extra points are given for low temperature environment during
>>> field operation. The contest happens in January when in some places
>>> temperatures can be down to minus 30 C. I did not find temperature
>>> requirements for K3/KX3 in the specs. Can somebody give me a hint or may
>>> be
>>> share own experience. What would be the lowest temperature where the rig
>>> will still perform adequately?
>>>
>>> 73, Igor UA9CDC
>>>
>>> ______________________________________________________________
>>> 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]
>