All,
So the K2 yielded up its first sideband QSO this evening. 10M
roundtable of the local ham club. People gave me good reports.
The next step is to organize up some power. The KPA100 is a mighty
elegant package, but I'm having trouble getting my head around the price
tag.
An alternative might be one of those Chinese amp
kits off Ebay. I actually have one in hand. It requires a bit of
redesign to work well. Mostly,
going to a bifilar-transformer power feed and verifying/optimizing the
input and output turns ratios. And providing a proper switched LPF.
- Jerry KF6VB
On 2021-06-30 19:54, Bill Coleman wrote:
The K2SB was absolutely the hardest kit to build out of the entire K2.
There are a lot of parts, and it is a very small board.
On Jun 30, 2021, at 10:06 PM, jerry <je...@tr2.com> wrote:
So I got up at 5:30 this morning and continued stuffing the SSB
adapter card. Finished it up this afternoon.
Trying it out, the CPU came up... CW still worked... But no SSB
transmit, and the SSB receive was very very soft. Had to turn the AF
gain up all the way to hear
anything at all.
My untutored diagnosis - something was wrong with that 7-crystal SSB
filter.
So I pulled the card out, scrubbed it again with IPA, stuck it under
the microscope to look - again - for solder splashes and cold joints.
Scraped off a little something here & there. Also, I had doubts
about the connections to the input & output transformers. So I hit
those again with the soldering iron.
Put the card back in the K2 - and ...Wow! Lively SSB receive! RF out
on transmit!
Still need to align the rig. Piping the output into another ham rig
through a big attenuator - it sounds pretty good. One niggle -
carrier suppression. If it's nulled out for LSB, it's not for USB.
The nulls are in different places on the pot. I guess you set a
compromise position, and make sure the carrier is off the skirts of
the filter, so that can help.
- Jerry KF6VB
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to aa...@arrl.net
Bill Coleman, AA4LR, PP-ASEL Mail: aa...@arrl.net
Web: http://boringhamradiopart.blogspot.com
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com
