K2 Pwr Out Problems

[David VK2NU]

Hi All,

My K2 seems to have developed a power output problem.

Set-up is a QRP K2, with SSB, internal ATU and KIO2 options.

I get full power output on CW OK, but only get a Max of about 1w RF output on SSB.

If I remove the top lid, and therefore disconnect the internal ATU and KIO2, I then get full output on SSB and CW.

I've also tried just plugging in the ATU and leaving the KIO2 out of line, and this seems to give full output??

Could there be a problem on the KIO2 that is causing me to loose SSB output?? Leaving the KIO2 inline but turning it on and off in the menu does not effect things.

Any ideas..

Thanks

David, VK2NU
______________________________________________________________
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]

David,

While it is quite unusual, there indeed could be a problem with the
KIO2.  Plug in the KIO2 and check the voltage at KIO2 J2 pin 7.  It
should be from 4.5 to 6 volts (that voltage comes from the KSB2 board).  
You should see the same voltage at Control Board P4 pin 7.
If the voltage is lower than expected, unplug the KIO2 and again check
the voltage at CB P4 pin 7.  Did it increase?  If so, then examine the
KIO2 for the solder bridge that is causing it.
Note that the KIO2 has no circuits in the path for this "EXT ALC" signal
- the KIO2 is simply a conduit for the wiring coming from KIO2 J1 pin
4.  It could also be that your K2 to computer cable has a solder bridge
between pins 3 and 4 which could cause the same condition.

73,
Don W3FPR

David Douglass wrote:

> Hi All,
>
> My K2 seems to have developed a power output problem.
>
> Set-up is a QRP K2, with SSB, internal ATU and KIO2 options.
>
> I get full power output on CW OK, but only get a Max of about 1w RF output on SSB.
>
> If I remove the top lid, and therefore disconnect the internal ATU and KIO2, I then get full output on SSB and CW.
>
> I've also tried just plugging in the ATU and leaving the KIO2 out of line, and this seems to give full output??
>
> Could there be a problem on the KIO2 that is causing me to loose SSB output?? Leaving the KIO2 inline but turning it on and off in the menu does not effect things.
>
> Any ideas..
>
> Thanks
>
> David, VK2NU
> ______________________________________________________________
> 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
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.791 / Virus Database: 271.1.1/2781 - Release Date: 03/31/10 02:32:00
>
>  

______________________________________________________________
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