Elecraft

[K3] Power control sensitivity with KPA500

Classic

List

Threaded

3 messages Options

N7US

[K3] Power control sensitivity with KPA500

I've only had my KPA500 for a couple of weeks. It seems to have so much
gain that adjusting the K3's power control takes a very fine touch to drive
the amplifier to the desired 500W without overshooting. It's too easy for
me to add 50W of KPA500 output when I really want, say, 10w or 20W, but
maybe I'm being too finicky.

I normally use the per-band tune menu option so it's only a problem when
adjusting the drive, of course.

I'd appreciate having a K3 menu item to adjust the sensitivity of the power
control.

73, Jim N7US

______________________________________________________________
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

Don Wilhelm-4

Re: [K3] Power control sensitivity with KPA500

Jim,

If you want more precise power control at levels below 100 watts, why
not put the KPA500 into standby?
The KPA500 has approximately 15 dB of gain, so the resolution in power
output is 15 dB (31.62 times) worse than the power resolution on the 100
watt K3.

With the KPA500 in standby, the sensitivity of the power knob will be
31.62 times better than with the KPA500 active.

73,
Don W3FPR

On 4/27/2013 10:03 PM, Jim McDonald wrote:

> I've only had my KPA500 for a couple of weeks. It seems to have so much
> gain that adjusting the K3's power control takes a very fine touch to drive
> the amplifier to the desired 500W without overshooting. It's too easy for
> me to add 50W of KPA500 output when I really want, say, 10w or 20W, but
> maybe I'm being too finicky.
>
> I normally use the per-band tune menu option so it's only a problem when
> adjusting the drive, of course.
>
> I'd appreciate having a K3 menu item to adjust the sensitivity of the power
> control.
>
>

______________________________________________________________
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

k6dgw

Re: [K3] Power control sensitivity with KPA500

In reply to this post by N7US

Hmmmm ... strange.

Mine isn't at all sensitive and once set, I never really touch it. One
thing ... like most Elecraft rigs, the instantaneous power out of the K3
will adjust on the first couple of dots or dashes [or syllables] to a
new setting. If I change the K3 drive setting, even by one watt, the
KPA500 usually hits 700W on the first dot or dash. After that, it
settles back immediately. The amp is a bit conservatively designed :-),
I've run mine on RTTY at 550W for a whole contest. I think it's just
the internal ALC working.

One thing I would like is instead of the K3 telling me the amp is in
standby or operate, it tells me the power the K3 is going to deliver
when I first tap the key after changing the amp status. The per-band
tune function has not worked for me on very rare occasions. I'm sure
it's pilot error, just don't know what I've done when it happens.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2013 Cal QSO Party 5-6 Oct 2013
- www.cqp.org

On 4/27/2013 7:03 PM, Jim McDonald wrote: