Hi Don, Good suggestion on the cables.. I swapped them out and whatever I did, it now shows a nice flat SWR on 20m. Perhaps something was loose or maybe the patch cable I was using as seen better days. ? Any idea why it might be showing 3 watts out as opposed to 4? Not that it makes much difference, just worked Serbia, Sardinia and Croatia with 3 watts :) ? 73 & thanks, ? James KB2FCV
-----Original Message----- From: Don Wilhelm <[email protected]> To: james1787 <[email protected]> Cc: elecraft <[email protected]> Sent: Mon, Jan 2, 2012 6:07 pm Subject: Re: [Elecraft] Not sure my KX1 ATU is working correctly James, There is nothing band dependent about the tuner - especially in CAL mode where all the L and C is bypassed. Try the test on 20 meters again. There are times when the KX1 "glitches" on an SWR reading, so if you see 9.9 SWR try it again. Also check your coax connections - make certain your cables are OK, especially if you are using adapters - make certain both male and female UHF connectors are tight (they depend on being tight for the shield path, BNC and N connectors do not have that dependency). Another thing to consider - is the KX1 BNC connector well soldered on the ground side - it takes a LOT of heat (and time) to make a good solder connection between that connector and the board ground.? Make certain you apply heat (use a large iron tip if possible) and be sure the solder actually flows instead of just being "pasted on".? If there is a bad connection at that BNC jack, it could explain an occasional SWR = 9.9 indication. 73, Don W3FPR On 1/2/2012 3:22 PM, [email protected] wrote: Hi Don, I followed your instructions and did the following: I removed my ATU from the KX1 and put the jumper in place. With my shack tuner, using my Icom I tuned it for a perfectly?flat SWR on 20 meters. I moved the coax from my Icom to my KX1. I peaked the 20a and 20b trimmers I moved the coax back to my icom and tuned the shack tuner for 40 meters I moved the coax back to my KX1 and peaked the 40 trimmer I removed the jumper in the KX1 and re-installed the ATU and set it to CAL. I connected the KX1 to my dummy load (Bird ERI-003F 150 watt 50 ohm dummy load) I changed bands on the KX1 to 20m I proceeded to adjust trimmer capacitor C9. I was able to get the voltage to .000 (it had a range from about 2.9 volts and bottomed out at .000). The power meter was only showing about 2.8 watts and the SWR showed 1.0 I connected my icom back up and re-tuned the antenna for 20m I moved the coax from my icom back to my kx1. With the KX1 still in cal, I pressed tune. Now the power was showing about 1.9 watts and 9.9 (infinite) SWR. I moved the from the KX1 to my icom and tuned the antenna for 40m. I changed bands on the KX1 to 40m I moved the antenna from my icom back to the kx1 and made sure it was stil on CAL. I pressed tune and it was showing 2.9 watts out and 1.0 swr. ? These are the results. I'm not sure if I was supposed to see it dip to .000 volts or not. It definitely appears the issue is something with 20m. I wish I had a wattmeter for QRP to see what the power/swr was doing without the ATU on 20m. Also, I have a 13.8 volt supply connected, 3 watts sounds a bit low? ? 73, James KB2FCV ? -----Original Message----- From: Don Wilhelm <[email protected]> To: james1787 <[email protected]> Cc: elecraft <[email protected]> Sent: Mon, Jan 2, 2012 1:30 pm Subject: Re: [Elecraft] Not sure my KX1 ATU is working correctly James, I am not sure from your prblem description whether you have a KX1 receiver problem or a KXAT1 problem or some sort of setup problem with your shack tuner. First thing to do is to peak the KX1 receiver front end, and you remove the tuner (put the jumper in) and connect it to a signal generator or to an antenna that presents close to a 50 ohm load. Do the following things in order: You have a shack tuner, so I suggest you set it for a 1:1 SWR - you can do that with another transmitter or with an antenna analyzer - set it up first for 20 meters. Once you have a 50 ohm signal source connected to the KX1 input, peak the 20A and 20B trimmers for the maximum output from the KX1. Re-tune your shack tuner to 40 meters, then connect the KX1 and peak the 40 meter trimmer - it must be done in that band order, reversing it will only lead to frustration. After having done that, you can remove the jumper and install the KXAT1 and set ATU to CAL First connect a good 50 ohm dummy load and balance (null) the wattmeter with the trimmer capacitor. If you can obtain a good low millivolts reading, that is good - above .010 volts is bad, below .003 volts may be the best you can do. With the KXAT1 still in CAL, again tune your shack tuner to 50 ohms on 20 - now you can compare the KX1 receive with you other receiver. Then set the ATU menu to "tun" and it should tune to less than 1.2 and you should still be able to hear signals at the same level as before Switch your shack tuner to 40 meters and do the same as you did on 20. After doing that, if you still have a problem, ask again. On 1/2/2012 12:34 PM, [email protected] wrote: > Hi Folks, > I just finished putting together my KX1 with the ATU. I am having a problem with it on 20m when using it through my shack tuner (viking matchbox to a dipole up 60-70 ft). As the manual states, I place the tuner into CAL to bypass the tuner. The problem is that it seems kind of quiet. I listen to a loud S-9 signal on my IC-746pro and it is much quieter on the KX1. For kick's I placed it in the tuner-on setting and hit tune. It tuned for a seconds and now it's louder. I tapped the key and it went back to being quiet. > ? > I didn't seem to notice this on 40m last night and made a few QSO's. > ? > Just wondering where I might check to see that everything is ok. I wonder if C9 on the ATU is set correctly? With my DMM I was able to get the voltage down to almost zero. > ? > Thanks& 73, > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
