ATU TUN power levels


Mike Kopacki
 

Thanks, Bob. I understand it now!

Thanks,
Mike

On Nov 29, 2022, at 8:35 PM, Bob McGraw - K4TAX <rmcgraw@...> wrote:

Mike:
My Cady is the first printing, Revision 1.4.   I didn't think about different versions. 
For 10 watts of power for the ATU TUNE, set the CONFIG menu TUN PWR to NOR.
For 5 watts of power for the ATU TUNE, set the CONFIG menu TUN PWR to some other value.  I use 20 watts. 

73
Bob, K4TAX


Bob McGraw - K4TAX
 

Mike:
My Cady is the first printing, Revision 1.4.   I didn't think about different versions. 
For 10 watts of power for the ATU TUNE, set the CONFIG menu TUN PWR to NOR.
For 5 watts of power for the ATU TUNE, set the CONFIG menu TUN PWR to some other value.  I use 20 watts. 

73
Bob, K4TAX


Mike Kopacki
 

Bob, maybe we have different versions of the Cady manual?  Page 174 is about connecting a PC with the K3 serial port cable.  I do see what you are saying on Page 167 though.  My original question was about what internally was making the switch from 5 to 10 watts which Wayne explained.

I have the third edition...

Thanks,
Mike NJ2OM


Bob McGraw - K4TAX
 

In the Fred Cady book, page 174 has the table in which one item is TUN PWR.  The box to the right of that does explain how 5 watts or 10 watts is selected.  In order to have 10 watts of tune power one must have TUN PWR set to NOR.

That's the way I read the description and that is the way I have confirmed my radio works.

73
Bob, K4TAX


 

My comments apply to ATU TUNE, not regular TUNE, which as Bob noted is controlled by CONFIG MENU: TUNE PWR.

Wayne

On Nov 28, 2022, at 6:00 PM, Mike Kopacki <mikekopacki@...> wrote:

Wow thanks, Wayne!

Thanks,
Mike

On Nov 28, 2022, at 8:56 PM, Bob McGraw - K4TAX <rmcgraw@...> wrote:

With the KPA3 in NOR, I find the ATU TUNE power to be 5.0 watts. With the KPA3 in BYP, I find the ATU TUNE power to also be 5.0 watts. Now with the TUNE PWR set to NOR, I find the ATU TUNE power to be 10 watts.


73
Bob, K4TAX


Mike Kopacki
 

Bob, P. 174 doesn’t say anything about tuning….

Thanks,
Mike

On Nov 28, 2022, at 9:00 PM, Mike Kopacki via groups.io <mikekopacki@...> wrote:

Wow thanks, Wayne!

Thanks,
Mike

On Nov 28, 2022, at 8:56 PM, Bob McGraw - K4TAX <rmcgraw@...> wrote:

With the KPA3 in NOR, I find the ATU TUNE power to be 5.0 watts.  With the KPA3 in BYP, I find the ATU TUNE power to also be 5.0 watts.    Now with the TUNE PWR set to NOR, I find the ATU TUNE power to be 10 watts.


73
Bob, K4TAX


Mike Kopacki
 

Wow thanks, Wayne!

Thanks,
Mike

On Nov 28, 2022, at 8:56 PM, Bob McGraw - K4TAX <rmcgraw@...> wrote:

With the KPA3 in NOR, I find the ATU TUNE power to be 5.0 watts.  With the KPA3 in BYP, I find the ATU TUNE power to also be 5.0 watts.    Now with the TUNE PWR set to NOR, I find the ATU TUNE power to be 10 watts.


73
Bob, K4TAX


Bob McGraw - K4TAX
 
Edited

With the KPA3 in NOR, I find the ATU TUNE power to be 5.0 watts.  With the KPA3 in BYP, I find the ATU TUNE power to also be 5.0 watts.    Now with the TUNE PWR set to NOR, I find the ATU TUNE power to be 10 watts.

See page 174 in the Fred Cady manual, TUN PWR

73
Bob, K4TAX


 

5 Watts is used for the early ATU tuning phases to avoid the need to roll back drive due to reflected power. When we get to the fine-tune phase where SWR is known to be 3:1 or better, we switch to 10 watts. This improves resolution of the bridge a bit, allowing us to accurately measure down to 1.0:1.

73,
Wayne
N6KR

On Nov 28, 2022, at 5:33 PM, Mike Kopacki <mikekopacki@...> wrote:

The K3S owner's manual and the Fred Cady manual both say that when the [ATU TUN] button is tapped, the output power is either 5 or 10 watts and is controlled internally. I can't find anything, anywhere, that says what determines whether it is 5 or 10 watts. Anyone know the answer and where it is written?

Thanks,
Mike NJ2OM


Mike Kopacki
 

The K3S owner's manual and the Fred Cady manual both say that when the [ATU TUN] button is tapped, the output power is either 5 or 10 watts and is controlled internally.  I can't find anything, anywhere, that says what determines whether it is 5 or 10 watts.  Anyone know the answer and where it is written?

Thanks,
Mike NJ2OM