Question on KPA-1500 Operation

[Elecraft mailing list]

Can someone answer this question?

Thanks,

N2TK, Tony

 

 

Here's a question for you:

 

Scenario:  KPA-1500 **NOT** interfaced to a radio.

 

Set Up:  KPA-1500 ATU in bypass.  Mode is Operate.

 

Test:

 

1.  Put amp on 14 MHz band by pushing the button.

2.  Monitoring on another radio connected to no antenna.

3.  Put transmitter on 14025 kHz and send a C on the paddle or via memory keyer.

 

Question:

 

On the separate RX, was the first dash in the C clipped?

 

4.  Move the transmitter and separate RX to 14050 kHz.

5.  Send another C on the paddle or memory keyer.

 

Question:

 

Was the first dash in the C clipped?

 

My reason for asking:  Doing this test with the SPE 2K-FA results in first dash of the C being clipped.

Why is this important:  In SO2V when CQing on VFO-A, and S&P on VFO-B, the 2K-FA's firmware

sees the 14025 RF and adjusts the internal ATU for that frequency EVEN IF THE ATU IS BYPASSED.

When a spot in VFO-B is called, if VFO-B is in another ATU segment, EVEN IF THE ATU IS BYPASSED,

the amp goes into bypass, realigns the ATU for the new segment, and then goes back into operate,

the result being that the first character of the transmission of VFO-B is clipped.  Many times when I

dump my call in on VFO-B to answer a CQ on that frequency, the guy comes back "?" since my N is

clipped into something unrecognizable.

 

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[Dick Dievendorff-4]

I’ll check when I get back home. We shouldn’t be clipping anything related to ATU if the ATU is bypassed, or if the ATU settings required are already set. We have to interrupt to change ATU relays if the ATU is not bypassed and different ATU setting is needed.

73 de Dick, K6KR

Sent from my iPhone

> On Aug 25, 2020, at 14:06, N2TK via Elecraft <[hidden email]> wrote:
>
> Can someone answer this question?
>
> Thanks,
>
> N2TK, Tony
>
>
>
>
>
> Here's a question for you:
>
>
>
> Scenario:  KPA-1500 **NOT** interfaced to a radio.
>
>
>
> Set Up:  KPA-1500 ATU in bypass.  Mode is Operate.
>
>
>
> Test:
>
>
>
> 1.  Put amp on 14 MHz band by pushing the button.
>
> 2.  Monitoring on another radio connected to no antenna.
>
> 3.  Put transmitter on 14025 kHz and send a C on the paddle or via memory keyer.
>
>
>
> Question:
>
>
>
> On the separate RX, was the first dash in the C clipped?
>
>
>
> 4.  Move the transmitter and separate RX to 14050 kHz.
>
> 5.  Send another C on the paddle or memory keyer.
>
>
>
> Question:
>
>
>
> Was the first dash in the C clipped?
>
>
>
> My reason for asking:  Doing this test with the SPE 2K-FA results in first dash of the C being clipped.
>
> Why is this important:  In SO2V when CQing on VFO-A, and S&P on VFO-B, the 2K-FA's firmware
>
> sees the 14025 RF and adjusts the internal ATU for that frequency EVEN IF THE ATU IS BYPASSED.
>
> When a spot in VFO-B is called, if VFO-B is in another ATU segment, EVEN IF THE ATU IS BYPASSED,
>
> the amp goes into bypass, realigns the ATU for the new segment, and then goes back into operate,
>
> the result being that the first character of the transmission of VFO-B is clipped.  Many times when I
>
> dump my call in on VFO-B to answer a CQ on that frequency, the guy comes back "?" since my N is
>
> clipped into something unrecognizable.
>
>
>
> ______________________________________________________________
> 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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Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]