Re: [Elecraft] K1 Low Power on 20M band once ATU is installed...fixed!
Michael, C13 is the Transmit Offset capacitor adjustment. It is quite possible that there was a bit of oxidation between the rotor and the fixed plate which was cleared by rotating the trimmer. 73, Don W3FPR On 2/27/2016 11:03 PM, n2...@aol.com wrote: Well it is finally fixed. When I went to listen to the signal on my K3 I noticed the frequency was off around 500 Hz or so. Tried to adjust the sidetone pitch and nothing happened - test mode audio was weak and frequency would not change with C13. I moved C13 back and forth a little and the tone came in nice and strong - with a adjustable pitch. Re-installed ATU and now a full 5.5 Watts on 20 Meters using a 3 cell Li-Po (12.2 Vdc)! Looks like a defective C13 or cold solder joint. The owner of this K1 will be happy when he hears this news! 73's Michael n2zdb __ 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
Re: [Elecraft] K1 Low Power on 20M band once ATU is installed...
Michael, One possibility is a bad relay or a relay mounted backwards or a relay with a poorly soldered connection. You cannot reliably check the inductor relays without removing one lead of the inductors. Do that first. Then in menu ATU CLP you should have continuity through all the inductor relays. L0 is the state where no inductors are selected, similarly, C0 is the state where no capacitors are selected. I can draw no conclusions from the relative power output between 40 and 20 meters. You will have to lift one lead of all the inductors and see if there is end to end (input to output) conductivity. You should be able to do that with a DC ohmmeter. If you do not have end to end continuity, you can check each of the relays that short out the inductors to see which is the problematic one. 73, Don W3FPR On 2/27/2016 9:53 PM, Michael via Elecraft wrote: Still have not figured out what's wrong with my newly built K1 w/ ATU. For some reason everything is fine on the 40 M band but once I switch to 20 M the power output drops way down. On the low part of the band the power output is much higher but still too low. I went thru all the C and L parameters in the ATU menu and checked the TX output power and SWR. Here is what I found: http://n2zdb.com/K1problem20M.jpg Since there are 4 inductors and 5 capacitors what does L0 and C0 represent? Figuring there was a problem with an inductor - I added a short between all the inductors at the relays (pins 3 to 4). This did not make a difference. However when a wire was added to K1 pin 4 to k4 pin 3 the power did come up a couple of Watts. I need an EXPERT to figure this out...does anyone have any ideas? 73's Michael n2zdb __ 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 w3...@embarqmail.com __ 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
Re: [Elecraft] K1 Low Power on 20M band once ATU is installed...
Michael, Did you change the jumper next to the BNC jack when you installed the KAT1? If you failed to do that, the K1 would show a low power even though it was actually developing full power output. Make sure the ATU menu is set to CAL P. If you are measuring power output with an external wattmeter, then check the soldering of the KAT1 toroid leads. You should not see any enamel on the solder side of the board and you should see a bit of tinned lead above the board. 73, Don W3FPR On 2/13/2016 11:11 PM, Michael via Elecraft wrote: I just built a new K1 and had some problems with the output power. To make a long story short I ended up having to lower the values of R5 and R11... This brought the power levels up on the 40 M band from 1.5 to 6.5 Watts and on the 20 M band from 0.5 to 5.5 Watts. Figured all was well now until I installed the new ATU For some reason my output power on the 20M band into a 50 Ohm dummy load is only around 0.7 Watts now with the ATU installed. If I remove it - it goes back up to normal! Any ideas? Thanks, Michael n2zdb __ 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 w3...@embarqmail.com __ 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
