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KPA500 Attenuation in Operate

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Jack Satterfield

KPA500 Attenuation in Operate

This one has me scratching my head, when switching KPA500 from standby to
operate the receiver signal drops about 30db otherwise it is operating
Normally.

Suggestions appreciated

Jack

W4GRJ

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george allen

Re: KPA500 Attenuation in Operate

If the KPA500 is not tuned to the frequency you listening to, the signal strength will be way down as the radio is not tuned to the antenna. Transmit to tune the antenna, and the signal will come back up. When in standby or off, the tuner is out of the circuit so the antenna match MAY be some what better.

I too, see this in my shack. For example, tuner is on automatic, last tranmit band was 20mtrs, and I listen to 40 mtrs...signal way down. Transmit, the tuner tunes, and the signal strength is normal.

If you have your K3 connected to the tuner to supply frequency info to the tuner, and you have "trained" the tuner to preset tuning for frequencies you use, this should not happen.

In my case I am using a Flex6700 with the tuner...freq info not sent to the tuner, so this is common for me.

Sent from my iPad

> On Apr 24, 2016, at 7:12 AM, Jack Satterfield <[hidden email]> wrote:
>
> This one has me scratching my head, when switching KPA500 from standby to
> operate the receiver signal drops about 30db otherwise it is operating
> Normally.
>
> Suggestions appreciated
>
> Jack
>
> W4GRJ
>
> ______________________________________________________________
> 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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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Jack Satterfield

Re: KPA500 Attenuation in Operate

I really don't understand your comments since there is no tuner in the KPA500
Jack
W4GRJ

On Apr 24, 2016, at 10:14 AM, george allen <[hidden email]> wrote:

If the KPA500 is not tuned to the frequency you listening to, the signal strength will be way down as the radio is not tuned to the antenna. Transmit to tune the antenna, and the signal will come back up. When in standby or off, the tuner is out of the circuit so the antenna match MAY be some what better.

I too, see this in my shack. For example, tuner is on automatic, last tranmit band was 20mtrs, and I listen to 40 mtrs...signal way down. Transmit, the tuner tunes, and the signal strength is normal.

If you have your K3 connected to the tuner to supply frequency info to the tuner, and you have "trained" the tuner to preset tuning for frequencies you use, this should not happen.

In my case I am using a Flex6700 with the tuner...freq info not sent to the tuner, so this is common for me.

Sent from my iPad

george allen

Re: KPA500 Attenuation in Operate

Oooops, sorry Jack...was thinking of the KAT500 antenna tuner. I have both the KAT500 tuner and the KPA500 amp. I have not seen your issue with the amp....but, do see a similar issue with the tuner.

Sent from my iPad

> On Apr 24, 2016, at 10:17 AM, Jack <[hidden email]> wrote:
>
> I really don't understand your comments since there is no tuner in the KPA500
> Jack
> W4GRJ
>
> On Apr 24, 2016, at 10:14 AM, george allen <[hidden email]> wrote:
>
> If the KPA500 is not tuned to the frequency you listening to, the signal strength will be way idown as the radio is not tuned to the antenna. Transmit to tune the antenna, and the signal will come back up. When in standby or off, the tuner is out of the circuit so the antenna match MAY be some what better.
>
> I too, see this in my shack. For example, tuner is on automatic, last tranmit band was 20mtrs, and I listen to 40 mtrs...signal way down. Transmit, the tuner tunes, and the signal strength is normal.
>
> If you have your K3 connected to the tuner to supply frequency info to the tuner, and you have "trained" the tuner to preset tuning for frequencies you use, this should not happen.
>
> In my case I am using a Flex6700 with the tuner...freq info not sent to the tuner, so this is common for me.
>
> Sent from my iPad
>
>> On Apr 24, 2016, at 7:12 AM, Jack Satterfield <[hidden email]> wrote:
>>
>> This one has me scratching my head, when switching KPA500 from standby to
>> operate the receiver signal drops about 30db otherwise it is operating
>> Normally.
>>
>> Suggestions appreciated
>>
>> Jack
>>
>> W4GRJ
>>
>> ______________________________________________________________
>> 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]

Jack Satterfield

Re: KPA500 Attenuation in Operate

Ok...here is the solution, Craig at Elecraft immediately suggested I check R7 on the LPF board. Good suggestion since it was missing...he is sending me R7 smt which should fix the problem.
Jack
W4GRJ

On Apr 24, 2016, at 10:46 AM, george allen <[hidden email]> wrote:

Oooops, sorry Jack...was thinking of the KAT500 antenna tuner. I have both the KAT500 tuner and the KPA500 amp. I have not seen your issue with the amp....but, do see a similar issue with the tuner.

Sent from my iPad