Re: K3- Higher Power on Transverter bands??

[Bruce Beford-2]

Hi, Roger.
 
What's in a name? Herein lies some of the confusion. On the K3, the 100W amp
is the KPA3, not KPA100 (K2 amp). As to your problem, would it not be more
efficient to use the low level output available from the KXV3(a) to drive
your transverter? This would eliminate the waste of all that power in the
dummy load, and provide a cleaner output, as the K3 LPA board (12w amp) is
not used, I believe.
 
Good luck,
Bruce, N1RX
 
> I should have said that it is a K3 I have.
 
> Is it possible to change the cut-in point of the KPA100 ??  Mine seems
fixed
> at 13 watts.
 
> The problem is (ref page 39 - Using Transverters) is that you cannot set
XVn
> PWR to more than 12 watts.  Thus you cannot get the clean signal from the
> KPA100.
 
> Roger - G4BVY
 

 

______________________________________________________________
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

[G4BVY]

Hi Bruce
Thanks for clearing up the confusion that I caused.

Yes, your solution of the low power out is really the way to go.

However (!!) I am resurrecting my old 70cms system for the European VHF
Field Day this weekend.  That was designed many many years ago to work with
the then availability of 10 watt transceivers.  To gut the system to
interface at low power is one step to far in the time available!

I guess the easy solution is just to use 28MHz at a clean 13 watts drive and
accept that the display (and the logging programme) will show 28.200 rather
than 432.200 !!

Roger - G4BVY

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Bruce Beford
Sent: 29 June 2011 08:42
To: [hidden email]
Subject: Re: [Elecraft] K3- Higher Power on Transverter bands??

Hi, Roger.
 
What's in a name? Herein lies some of the confusion. On the K3, the 100W amp
is the KPA3, not KPA100 (K2 amp). As to your problem, would it not be more
efficient to use the low level output available from the KXV3(a) to drive
your transverter? This would eliminate the waste of all that power in the
dummy load, and provide a cleaner output, as the K3 LPA board (12w amp) is
not used, I believe.
 
Good luck,
Bruce, N1RX
 
> I should have said that it is a K3 I have.
 
> Is it possible to change the cut-in point of the KPA100 ??  Mine seems
fixed
> at 13 watts.
 
> The problem is (ref page 39 - Using Transverters) is that you cannot
> set
XVn
> PWR to more than 12 watts.  Thus you cannot get the clean signal from
> the KPA100.
 
> Roger - G4BVY
 

 

______________________________________________________________
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

______________________________________________________________
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

[Bruce Beford-2]

Ah, I see. Time is always the enemy, isn't it? 8-)
Have fun this weekend in the VHF Field Day!
73,
Bruce, N1RX
 
 
> However (!!) I am resurrecting my old 70cms system for the European VHF
> Field Day this weekend.  That was designed many many years ago to work
with
> the then availability of 10 watt transceivers.  To gut the system to
> interface at low power is one step to far in the time available!

 

______________________________________________________________
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

[Geoffrey Mackenzie-Kennedy]

Hi Roger,

I should have twigged that you were using a K3 not a K2, so many thanks to
Bruce N1RX for his comment.

The low power drive solution would be the best option IF you had the time,
provided of course that the IMD contributed by any additional amp if
required in the transverter was insignificant.

Good luck this weekend!

73,
Geoff
GM4ESD


On June 29, 2011 at 09:10 Z, Roger Dixon wrote:

> Hi Bruce
> Thanks for clearing up the confusion that I caused.
>
> Yes, your solution of the low power out is really the way to go.
>
> However (!!) I am resurrecting my old 70cms system for the European VHF
> Field Day this weekend.  That was designed many many years ago to work
> with
> the then availability of 10 watt transceivers.  To gut the system to
> interface at low power is one step to far in the time available!
>
> I guess the easy solution is just to use 28MHz at a clean 13 watts drive
> and
> accept that the display (and the logging programme) will show 28.200
> rather
> than 432.200 !!
>
> Roger - G4BVY

______________________________________________________________
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