KX1 Serial #01872
Locked
 
|
I managed to get my unit built up and installed in a bout 8 hours or so.
Everything went very well by following the check list to the letter. I caught myself installing a cap in the wrong position just once but some quick work with a bit of solder wick took care of that. This is just a basic KX1 with no options yet. Alignment and testing for 40 meters sounds great but 20 meters I have to take my AF volume quite high before I hear the noise. I could copy stations on 20 meters last night just fine but had to crank the AF volume pot to about 3/4 volume before I heard the noise floor. Is this normal? I took the unit to work to use some of the nicer test gear to see if it was simply a lack of a good tweeker. I put a sig gen on the input with a carrier set at 14.100mhz @ -100dbm and was able to hear the signal just fine with the AF pot cranked up around 3/4 of the way. Tweeking on the 20A 20B cap's I was able to get things cranked up as high as they would go. Does this sound like expected behavior with the large difference between apparent noise level between 20M and 40M? Thanks and 73, Justin KL1RL _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
> Justin
> You said you had -100dbm - was that before or after peaking the caps? > I think mine will copy 1uv from my XG-1 which -107dbm so you seem to > be in the ball park. > I could go recheck really quick but i'm pretty sure I heard the CW with the sig gen set to around -110dbm after peaking the caps. I'm mainly concerned about the need for a high AF volume before hearing the noise floor. Granted the floor is going to be very low coming from the sig gen but I noticed this on the windom at home as well. I guess my main question is should I be making a large adjustment to the volume level when switching from 40 meters to 20 meters? Perhaps it's just new rig jitters hi hi > 73 John > WA8KNE > > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
Do be sure your earphone has at least -100 or better dbm sensitivity. I
won't buy one unless is better than -108. I have a set that does -120. Bill K9YEQ -----Original Message----- Subject: [Elecraft] Re: KX1 Serial #01872 > Justin Perhaps it's just new rig jitters hi hi > 73 John > WA8KNE _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
In reply to this post by Justin Burket
Justin,
The KX1 is relatively quiet, and the sensitivity of your headphones has a lot to do with how much the AF gain has to be advanced before you can hear the noise floor of the receiver. The important factor is not how loud the noise floor is, but how far above the noise floor is the signal. Since you have a calibrated signal generator, I suggest that you can easily observe the signal with Spectrogram (or other audio spectrum analyzer) if you connect the KX1 headphone output to a computer line-in jack - with the KX1, I usually expect to see a -120dBm signal well above the noise floor on any band - some bands will show an MDS better than -130dBm and other bands a bit worse. How is the transmit power on 20 compared to 40 meters. If the 20 meter output is significantly lower (below 3 watts), you may want to spread the turns of L2 a bit to raise the LFP cutoff frequency. The receive signal will also be reduced if the LPF cutoff is set too low. 73, Don W3FPR Justin Burket wrote: > I managed to get my unit built up and installed in a bout 8 hours or so. > Everything went very well by following the check list to the letter. I > caught myself installing a cap in the wrong position just once but some > quick work with a bit of solder wick took care of that. > > This is just a basic KX1 with no options yet. Alignment and testing for > 40 meters sounds great but 20 meters I have to take my AF volume quite > high before I hear the noise. I could copy stations on 20 meters last > night just fine but had to crank the AF volume pot to about 3/4 volume > before I heard the noise floor. Is this normal? > > I took the unit to work to use some of the nicer test gear to see if it > was simply a lack of a good tweeker. I put a sig gen on the input with a > carrier set at 14.100mhz @ -100dbm and was able to hear the signal just > fine with the AF pot cranked up around 3/4 of the way. Tweeking on the > 20A 20B cap's I was able to get things cranked up as high as they would > go. > > Does this sound like expected behavior with the large difference between > apparent noise level between 20M and 40M? > > Thanks and 73, > Justin KL1RL > > > > > > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
«
Return to Elecraft
|
1 view|%1 views
| Free forum by Nabble | Edit this page |