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A question on the P3 or actually the Tx Mon

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A question on the P3 or actually the Tx Mon

I placed the DCHF-200 after my antenna tuner. In other words, the DCHF-200 is between my tuner and antenna. When relying on my tuner to match the antenna to the radio My power meter (on the P3) is showing an SWR of a little over 13:1 (which is about right) . My meter on my tuner is showing about 92 watts of power headed down the antenna,but the meter on the P3 is showing over 200 watts. My intended output being 100 watts. Does the DCHF-200 show out-going pwr + reflected pwr? The tuner matches the antenna to the radio, and the tuner meter shows a very very small amt. of reflected power.
I put the DCHF-200 at this location, because if I had the tuner installed in the radio, this is where it would go.

The antenna is a fan dipole trimmed for 40 meters and 20 meters. I am on 3.810 MHz and without the tuner the SWR is about 13.2:1 here. The tuner matches the antenna to the radio with a SWR of very close to 1.0:1. .

AJ4YA
Grady

Thanks.

Sent from my iPad
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Alan Bloom

Re: A question on the P3 or actually the Tx Mon

The P3 shows total forward power. The power delivered to the feedline
is forward minus reflected.

With a 13:1 SWR, 73.5% of the power is reflected and 26.5% is
transmitted. If the transmitted power is 92 watts then the total
forward power should be 347 watts.

Alan N1AL

On 03/05/2017 06:58 PM, Grady Harper via Elecraft wrote:

> I placed the DCHF-200 after my antenna tuner. In other words, the
> DCHF-200 is between my tuner and antenna. When relying on my tuner
> to match the antenna to the radio My power meter (on the P3) is
> showing an SWR of a little over 13:1 (which is about right) . My
> meter on my tuner is showing about 92 watts of power headed down the
> antenna,but the meter on the P3 is showing over 200 watts. My
> intended output being 100 watts. Does the DCHF-200 show out-going
> pwr + reflected pwr? The tuner matches the antenna to the radio, and
> the tuner meter shows a very very small amt. of reflected power. I
> put the DCHF-200 at this location, because if I had the tuner
> installed in the radio, this is where it would go.
>
> The antenna is a fan dipole trimmed for 40 meters and 20 meters. I
> am on 3.810 MHz and without the tuner the SWR is about 13.2:1 here.
> The tuner matches the antenna to the radio with a SWR of very close
> to 1.0:1. .
>
> AJ4YA Grady
>
> Thanks.
>
> Sent from my iPad
> ______________________________________________________________
> 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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Vic Rosenthal

Re: A question on the P3 or actually the Tx Mon

This is one of my pet peeves with the W2 -- it does not have an option for delivered power. Yes, I know how to subtract, but it's beyond trivial to do this in the software, and it would be convenient.

Vic 4X6GP

> On 6 Mar 2017, at 05:32, Alan Bloom <[hidden email]> wrote:
>
> The P3 shows total forward power. The power delivered to the feedline is forward minus reflected.
>
> With a 13:1 SWR, 73.5% of the power is reflected and 26.5% is transmitted. If the transmitted power is 92 watts then the total forward power should be 347 watts.
>
> Alan N1AL
>
>
>> On 03/05/2017 06:58 PM, Grady Harper via Elecraft wrote:
>> I placed the DCHF-200 after my antenna tuner. In other words, the
>> DCHF-200 is between my tuner and antenna. When relying on my tuner
>> to match the antenna to the radio My power meter (on the P3) is
>> showing an SWR of a little over 13:1 (which is about right) . My
>> meter on my tuner is showing about 92 watts of power headed down the
>> antenna,but the meter on the P3 is showing over 200 watts. My
>> intended output being 100 watts. Does the DCHF-200 show out-going
>> pwr + reflected pwr? The tuner matches the antenna to the radio, and
>> the tuner meter shows a very very small amt. of reflected power. I
>> put the DCHF-200 at this location, because if I had the tuner
>> installed in the radio, this is where it would go.
>>
>> The antenna is a fan dipole trimmed for 40 meters and 20 meters. I
>> am on 3.810 MHz and without the tuner the SWR is about 13.2:1 here.
>> The tuner matches the antenna to the radio with a SWR of very close
>> to 1.0:1. .
>>
>> AJ4YA Grady
>>
>> Thanks.
>>
>> Sent from my iPad
>> ______________________________________________________________
>> 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
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>
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> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Arie Kleingeld PA3A-2

K3 RF gain

Inspired by all the info about K3's AGC, I remembered something that
bothered me before.

If I adjust the RF gain, which amplifier(s) in the K3 block diagram am I
adjusting? I can guess but I would like to know for sure.

73,

Arie PA3A

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Robert Cunnings

Re: K3 RF gain

The gain of the first IF amp.

There's a detailed description of the K3's RF gain control on the Clifton
Labs website, titled "Elecraft's K3 Transceiver and Manual Gain Control".
Here's the link:

http://www.cliftonlaboratories.com/elecraft_k3_and_manual_rf_gain_control.htm

Bob NW8L

On Mon, 6 Mar 2017, Arie Kleingeld PA3A wrote:

> Inspired by all the info about K3's AGC, I remembered something that bothered
> me before.
>
> If I adjust the RF gain, which amplifier(s) in the K3 block diagram am I
> adjusting? I can guess but I would like to know for sure.
>
>
> 73,
>
> Arie PA3A