Yet another KX-1 Question
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Yet another KX-1 Question
 
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I've been following the discussion on low power output from the KX-1
with interest. My problem is a little different, though. With a 12V gel cell, mine outputs 3.5 - 4 W on 40m, but I'm getting a watt or less out on 20m. Receiver sensitivity seems lower, too. I've tried readjusting the trimmers, but that didn't seem to help much. 73! Dan KB6NU ---------------------------------------------------------- CW Geek and MI Affiliated Club Coordinator Read my ham radio blog at www.kb6nu.com LET'S GET MORE KIDS INTO HAM RADIO! _______________________________________________ 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 |
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Dan,
I agree on the receiver sensitivity. I aligned my 2 band KX-1 with a -103 dBm signal. When I used a -73 dBm signal (standard S9), I got 4-5 bars on the S-meter for 40 and 20. Perfect! After building and installing the KXB3080 and doing all the RX alignments, I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. I expect the KX1 20m circuitry was compromised to pull it down to 80m. Just thought I'd share. 73, Glen, NK1N K1 #2144 KX1 #1516 Dan KB6NU <[hidden email]> wrote: I've been following the discussion on low power output from the KX-1 with interest. My problem is a little different, though. With a 12V gel cell, mine outputs 3.5 - 4 W on 40m, but I'm getting a watt or less out on 20m. Receiver sensitivity seems lower, too. I've tried readjusting the trimmers, but that didn't seem to help much. 73! Dan KB6NU ---------------------------------------------------------- CW Geek and MI Affiliated Club Coordinator Read my ham radio blog at www.kb6nu.com LET'S GET MORE KIDS INTO HAM RADIO! _______________________________________________ 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 |
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In reply to this post by Dan Romanchik KB6NU
Dan,
The trimmers will only change the receiver front end tuning, they will not have any effect on transmit. For transmit power output problems, the first thing to check is the Low Pass filter inductors. As a first step, make them look like the inductor diagrams in the manual, then use small 'tweaks' from there. Also check T1 for the proper number of turns on both windings. Remove the tuner (install jumper) and operate the KX1 directly into a 50 ohm dummy load when testing for power output. Monitor the power output with an RF Probe (or 'scope) connected across the dummy load. Unless you have some major error in the transmit components (wrong resistor or capacitor values), there is little that can go wrong with the transmit path. You can signal trace through the transmmit stages with an RF Probe comparing the RF Voltage levels on 40 meters with those on 20 meters to see where the signal is significantly lower on 20. 73, Don W3FPR > -----Original Message----- > > I've been following the discussion on low power output from the KX-1 > with interest. My problem is a little different, though. With a 12V > gel cell, mine outputs 3.5 - 4 W on 40m, but I'm getting a watt or > less out on 20m. Receiver sensitivity seems lower, too. I've tried > readjusting the trimmers, but that didn't seem to help much. > > 73! > > Dan KB6NU > _______________________________________________ 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 |
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In reply to this post by Glen Johnstone
Glen,
The receiver front end was changed, but I do not believe it was compromised in adding 80 meters. It is likely you have something wrong there. I have found the typical receive sensitivity improved on all bands after installation of the KXB8030. No drastic improvement, but definitely not worse than the 2/3 band receiver front end. 73, Don W3FPR > -----Original Message----- > > I agree on the receiver sensitivity. I aligned my 2 band KX-1 > with a -103 dBm signal. When I used a -73 dBm signal (standard > S9), I got 4-5 bars on the S-meter for 40 and 20. Perfect! > > After building and installing the KXB3080 and doing all the RX > alignments, I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. > > I expect the KX1 20m circuitry was compromised to pull it down to 80m. > > Just thought I'd share. 73, > Glen, NK1N > K1 #2144 > KX1 #1516 > _______________________________________________ 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 |
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Fair enough. I will take a closer look and report back. Many thanks.
73, Glen Don Wilhelm <[hidden email]> wrote: Glen, The receiver front end was changed, but I do not believe it was compromised in adding 80 meters. It is likely you have something wrong there. I have found the typical receive sensitivity improved on all bands after installation of the KXB8030. No drastic improvement, but definitely not worse than the 2/3 band receiver front end. 73, Don W3FPR > -----Original Message----- > > I agree on the receiver sensitivity. I aligned my 2 band KX-1 > with a -103 dBm signal. When I used a -73 dBm signal (standard > S9), I got 4-5 bars on the S-meter for 40 and 20. Perfect! > > After building and installing the KXB3080 and doing all the RX > alignments, I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. > > I expect the KX1 20m circuitry was compromised to pull it down to 80m. > > Just thought I'd share. 73, > Glen, NK1N > K1 #2144 > KX1 #1516 > _______________________________________________ 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 |
RE: Yet another KX-1 Question
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In reply to this post by Glen Johnstone
Glen, NK1N wrote:
I agree on the receiver sensitivity. I aligned my 2 band KX-1 with a -103 dBm signal. When I used a -73 dBm signal (standard S9), I got 4-5 bars on the S-meter for 40 and 20. Perfect! After building and installing the KXB3080 and doing all the RX alignments, I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. I expect the KX1 20m circuitry was compromised to pull it down to 80m. ------------------------------------- Just the opposite Glen. The receiver front end circuitry was redesigned to operate very efficiently across the 80-20 meter range. The original KXB3080 uses a simple capacitively-coupled input circuit. The KXB3080 mod replaces this with a transfomer-coupled input. I wouldn't suggest how effective looking at the "S-Meter" is for evaluating receiver performance. I haven't tried it. Running actual SN+N/N sensitivity tests, I found the end result was actually slightly *better* receiver performance on all four bands. Ron AC7AC _______________________________________________ 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 |
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Ron,
Thanks for the info. You are correct about the testing. I wouldn't have even done my test except it 'sounded' low. I'll be troubleshooting tonight. I may have miswound T2 or goofed on a component sub or better yet, soldered 'em to the wrong pads. I'll post my findings. 73, Glen, NK1N PS. I know you meant "origanal KX1". Ron D'Eau Claire <[hidden email]> wrote: Glen, NK1N wrote: I agree on the receiver sensitivity. I aligned my 2 band KX-1 with a -103 dBm signal. When I used a -73 dBm signal (standard S9), I got 4-5 bars on the S-meter for 40 and 20. Perfect! After building and installing the KXB3080 and doing all the RX alignments, I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. I expect the KX1 20m circuitry was compromised to pull it down to 80m. ------------------------------------- Just the opposite Glen. The receiver front end circuitry was redesigned to operate very efficiently across the 80-20 meter range. The original KXB3080 uses a simple capacitively-coupled input circuit. The KXB3080 mod replaces this with a transfomer-coupled input. I wouldn't suggest how effective looking at the "S-Meter" is for evaluating receiver performance. I haven't tried it. Running actual SN+N/N sensitivity tests, I found the end result was actually slightly *better* receiver performance on all four bands. Ron AC7AC _______________________________________________ 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 |
RE: Yet another KX-1 Question
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Yep. Too many times typing KXB3080 <G>.
73, Ron -----Original Message----- From: Glen Johnstone [mailto:[hidden email]] Sent: Monday, June 26, 2006 8:14 AM To: Ron D'Eau Claire; [hidden email] Subject: RE: [Elecraft] Yet another KX-1 Question Ron, Thanks for the info. You are correct about the testing. I wouldn't have even done my test except it 'sounded' low. I'll be troubleshooting tonight. I may have miswound T2 or goofed on a component sub or better yet, soldered 'em to the wrong pads. I'll post my findings. 73, Glen, NK1N PS. I know you meant "origanal KX1". _______________________________________________ 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 |
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In reply to this post by Glen Johnstone
OK. As promised. My findings!
All component values were correct. All soldering was done to the correct pads. All the joints looked good....until.... I took a really close look at T2's leads. On the bottom they looked great but on the top (really hard to see) they were not bonding to the pad. Either I didn't strip off enough enamel or shoved the lead in too far or both. Anyway, you folks were correct. I applied a little heat, a little more solder, waited a few seconds and voila'... You can guess the outcome. Thanks for assist! 72, Glen, NK1N ----- Original Message ----- From: "Glen Johnstone" <[hidden email]> To: "Ron D'Eau Claire" <[hidden email]>; <[hidden email]> Sent: Monday, June 26, 2006 11:14 AM Subject: RE: [Elecraft] Yet another KX-1 Question > Ron, > > Thanks for the info. You are correct about the testing. I wouldn't have > even done my test except it 'sounded' low. > > I'll be troubleshooting tonight. I may have miswound T2 or goofed on a > component sub or better yet, soldered 'em to the wrong pads. I'll post my > findings. > > 73, > Glen, NK1N > > PS. I know you meant "origanal KX1". > > Ron D'Eau Claire <[hidden email]> wrote: > Glen, NK1N wrote: > I agree on the receiver sensitivity. I aligned my 2 band KX-1 with a -103 > dBm signal. When I used a -73 dBm signal (standard S9), I got 4-5 bars on > the S-meter for 40 and 20. Perfect! > > After building and installing the KXB3080 and doing all the RX alignments, > I find the -73 dBm signal barely lights 2 bars on 20. Hmmm. > > I expect the KX1 20m circuitry was compromised to pull it down to 80m. > > ------------------------------------- > > Just the opposite Glen. > > The receiver front end circuitry was redesigned to operate very > efficiently > across the 80-20 meter range. The original KXB3080 uses a simple > capacitively-coupled input circuit. The KXB3080 mod replaces this with a > transfomer-coupled input. > > I wouldn't suggest how effective looking at the "S-Meter" is for > evaluating > receiver performance. I haven't tried it. Running actual SN+N/N > sensitivity > tests, I found the end result was actually slightly *better* receiver > performance on all four bands. > > Ron AC7AC > > _______________________________________________ > 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 _______________________________________________ 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 |
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