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KX3 and KPA-500

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George Rebong

KX3 and KPA-500

I would like to try this combination and wonder how many watts will I get out in the KPA-500.
Happy Thanks Giving

73
George

Sent from my iPad 3G
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Phil Genera

Re: KX3 and KPA-500

I don't have that particular combination, but a coworker does and posted
some photos of it:
https://plus.google.com/113939332173985992126/posts/FSZR2wwzP2n

He says he gets 220w out.

--
Phil
kj6pon

On Thu, Nov 28, 2013 at 12:34 PM, George Rebong <[hidden email]> wrote:

> I would like to try this combination and wonder how many watts will I get
> out in the KPA-500.
> Happy Thanks Giving
>
> 73
> George
>
> Sent from my iPad 3G
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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k6dgw

Re: KX3 and KPA-500

In reply to this post by George Rebong

On 11/28/2013 12:34 PM, George Rebong wrote:
> I would like to try this combination and wonder how many watts will I
> get out in the KPA-500. Happy Thanks Giving

27W from my K3 gives me 500W out of the KPA500 on 10m. That's ~13dB.
If your KX3 delivers 10W, you should see ~200W out.

gain[dB] = 10*log[P1/P0]

P1 = P0*10^[gain/10]

73,

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

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Dick Dievendorff-4

Re: KX3 and KPA-500

In reply to this post by George Rebong

The KPA500 provides between 12 to 14 dB gain depending on the amp and the
band.

FCC rule 97.317(a)(2) limits the gain of FCC-certified commercially sold
amplifiers for the amateur market to 15 dB of gain.

My KPA500 has about 12 dB of gain on 20 meters and about 13.5 dB of gain on
10 meters.

At 12 dB, on 20 meters, my amp requires 31 watts of K3 exciter power to
deliver 500 watts out.

As it's (pretty close to) a linear amplifier, you can scale the input and
output power linearly from that.
3.1 watts should deliver 50 watts.
6.2 watts should deliver 100 watts.
10 watts should deliver about 160 watts.

The KXPA100 has similar gain, up to its 100 watt specified maximum.

73 de Dick, K6KR

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of George Rebong
Sent: Thursday, November 28, 2013 12:34 PM
To: [hidden email]
Subject: [Elecraft] KX3 and KPA-500

I would like to try this combination and wonder how many watts will I get
out in the KPA-500.
Happy Thanks Giving

73
George

Sent from my iPad 3G
______________________________________________________________
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Nr4c

Re: KX3 and KPA-500

In reply to this post by George Rebong

I'm getting about 250 watts with ~7.5 watts drive. Works great. However it takes more than 10 watts to get good tune action on the KAT500.

...bill nr4c

Sent from my Verizon Wireless 4G LTE DROID

George Rebong <[hidden email]> wrote:

>I would like to try this combination and wonder how many watts will I get out in the KPA-500.
>Happy Thanks Giving
>
>73
>George
>
>Sent from my iPad 3G
>______________________________________________________________
>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
>

chrisrut

Re: KX3 and KPA-500

In reply to this post by George Rebong

Hi George.

I use a KX3 with a KPA500 as my everyday rig.

With the KX3 set for maximum output (12W) into resonant antennas (SWRs
<1.5:1) in the CW portions of the band I see from 160W on 20M up to
about 220W on 10M. I don't use SSB often enough to recall, but they in
a similar range.

Thus the real-world and the math agree.

Operationally, the auto-band changing of the amp allows me to QSY and
transmit without thinking about the amp - it just tracks nicely.
However, I -do- usually give the amp a single dit in STBY mode to get
the band right. No sense hot-switching everything needlessly.

73 Chris NW6V

> On Thu, Nov 28, 2013 at 12:34 PM, George Rebong <[hidden email]> wrote:
>
>> I would like to try this combination and wonder how many watts will I get
>> out in the KPA-500.
>> Happy Thanks Giving
>>
>> 73
>> George
>>
>> Sent from my iPad 3G

Robert Friess

Re: KX3 and KPA-500

Chris,

You don't have to go to STBY and send a dit for a band change to avoid hot
switching. When the need to bandswitch is detected, the KPA500
automatically goes to BYPASS, performs the band change, and then switches
itself back in line all within a small fraction of a second.

Bob, N6CM

On Fri, Nov 29, 2013 at 1:41 PM, Chris Rutkowski <[hidden email]>wrote:

> Hi George.
>
> I use a KX3 with a KPA500 as my everyday rig.
>
> With the KX3 set for maximum output (12W) into resonant antennas (SWRs
> <1.5:1) in the CW portions of the band I see from 160W on 20M up to
> about 220W on 10M. I don't use SSB often enough to recall, but they in
> a similar range.
>
> Thus the real-world and the math agree.
>
> Operationally, the auto-band changing of the amp allows me to QSY and
> transmit without thinking about the amp - it just tracks nicely.
> However, I -do- usually give the amp a single dit in STBY mode to get
> the band right. No sense hot-switching everything needlessly.
>
> 73 Chris NW6V
>
> > On Thu, Nov 28, 2013 at 12:34 PM, George Rebong <[hidden email]>
> wrote:
> >
> >> I would like to try this combination and wonder how many watts will I
> get
> >> out in the KPA-500.
> >> Happy Thanks Giving
> >>
> >> 73
> >> George
> >>
> >> Sent from my iPad 3G
> ______________________________________________________________
> 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
>

chrisrut

Re: KX3 and KPA-500

Bob,

Of course, you're right. I knew that - somewhere in my head. :-) I'm
sure I read it in a post or in the manual.

Guess it's a case of old habits dying hard; I find a low-key,
low-power dit to make sure everything is on the green -before- I need
it in a pile-up, reassuring. Largely unnecessary, it's true; but
reassuring none-the-less. It's not a big deal to me one way or the
other.

But thanks for the reminder.

73 Chris NW6V

On Fri, Nov 29, 2013 at 1:58 PM, Robert Friess <[hidden email]> wrote:

> Chris,
>
> You don't have to go to STBY and send a dit for a band change to avoid hot
> switching. When the need to bandswitch is detected, the KPA500
> automatically goes to BYPASS, performs the band change, and then switches
> itself back in line all within a small fraction of a second.
>
> Bob, N6CM
>
>
> On Fri, Nov 29, 2013 at 1:41 PM, Chris Rutkowski <[hidden email]>
> wrote:
>>
>> Hi George.
>>
>> I use a KX3 with a KPA500 as my everyday rig.
>>
>> With the KX3 set for maximum output (12W) into resonant antennas (SWRs
>> <1.5:1) in the CW portions of the band I see from 160W on 20M up to
>> about 220W on 10M. I don't use SSB often enough to recall, but they in
>> a similar range.
>>
>> Thus the real-world and the math agree.
>>
>> Operationally, the auto-band changing of the amp allows me to QSY and
>> transmit without thinking about the amp - it just tracks nicely.
>> However, I -do- usually give the amp a single dit in STBY mode to get
>> the band right. No sense hot-switching everything needlessly.
>>
>> 73 Chris NW6V
>>
>> > On Thu, Nov 28, 2013 at 12:34 PM, George Rebong <[hidden email]>
>> > wrote:
>> >
>> >> I would like to try this combination and wonder how many watts will I
>> >> get
>> >> out in the KPA-500.
>> >> Happy Thanks Giving
>> >>
>> >> 73
>> >> George
>> >>
>> >> Sent from my iPad 3G
>> ______________________________________________________________
>> 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
>
>