K2 TX alignment problems continue
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K2 TX alignment problems continue
 
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Hi all,
The symptom of my problem is: 1. when setting k2 power to 5 watts, I get a reading of 2.2 amps with abt 0.8v drop 2. when looking at power output with an external wattmeter, 5 watts reflecting on the external wattmeter shows as 3.8 on the k2. Similarly, 10 watts on external wattmeter is reading 6.9 on the k2 at an 2.8 amps. Cranking the rf power all the way clockwise shows 15 watts on k2 and hi pwr message (cal curr set to 3.25) and external wattmeter shows 19 watts. I examined T2 and had it too tight to the RF board so have re-installed with gap. Part 2 alignment works perfectly, part 3 resistance checks okay. I do not have a signal generator that can do 0.14vrms so have not done those receiver checks. In performing the transmit mixer, buffer, etc, tests, the readings do not look right at all. Xmit mixer output (pin 4 at U10) reads 0. Buffer output (pin 6 U9) reads 0.05 Band-pass Filter Output (W6) reads 0.014 T-R switch #1 Output reads 0.012. Any clues or things to test? Neal _______________________________________________ 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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Neal Campbell and Sarah Ferrell wrote:
> The symptom of my problem is: > 1. when setting k2 power to 5 watts, I get a reading of 2.2 amps with > abt 0.8v drop > 2. when looking at power output with an external wattmeter, 5 watts > reflecting on the external wattmeter shows as 3.8 on the k2. Similarly, > 10 watts on external wattmeter is reading 6.9 on the k2 at an 2.8 amps. > Cranking the rf power all the way clockwise shows 15 watts on k2 and hi > pwr message (cal curr set to 3.25) and external wattmeter shows 19 watts. The RF detector seems to be reading low. Check the RF detector components on the RF board: R66, R67, R68, R69, D9. Make sure the resistors are the correct values and the diode is the correct type. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________ 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: K2 TX alignment problems continue
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In reply to this post by Neal Campbell and Sarah Ferrell
Neal:
How sure are you that the wattmeter is reading correctly? What scale are you using to read the output on and are you operating the radio into a dummy load or an antenna? Also where are you measuring the 0.8 volt drop? That sounds like a pretty big drop in voltage with only 2.2 amps of current. One word of note - I have built thirteen K2's and have never seen one that would produce 19 watts output at any setting of the power control or any band. 73 Jim Younce K4ZM _______________________________________________ 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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k4zm wrote:
> I have built thirteen K2's and have never > seen one that would produce 19 watts output at any setting of the power > control or any band. The power output of the K2 is determined by an ALC feedback mechanism. When you set the power control to 5 watts, the ALC circuit increases the drive until the RF detector indicates that 5 watts is being output. If the RF detector indicates that less power is being produced, the ALC circuit will continue to increase drive. Although the RF detector in the basic K2 is not adjustable, the one in the KAT2 is. If you have a KAT2 it's quite easy to adjust the wattmeter circuit to fool the K2 into producing more power than the power control says. I had my K2 making 22 watts on 40 meters a couple of years ago when I was using the basic K2 to drive an external amplifier (now I have a KPA100). -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________ 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: K2 TX alignment problems continue
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In reply to this post by Vic K2VCO
The good news is that I did a diode dance, had the rf probe diode in
D9, had the real d9 substituted for a 4148 and a 4148 in the rf probe. Will swap them around and redo the tests! Neal On Feb 13, 2005, at 6:00 PM, Vic Rosenthal wrote: > Neal Campbell and Sarah Ferrell wrote: > >> The symptom of my problem is: >> 1. when setting k2 power to 5 watts, I get a reading of 2.2 amps with >> abt 0.8v drop >> 2. when looking at power output with an external wattmeter, 5 watts >> reflecting on the external wattmeter shows as 3.8 on the k2. >> Similarly, 10 watts on external wattmeter is reading 6.9 on the k2 at >> an 2.8 amps. Cranking the rf power all the way clockwise shows 15 >> watts on k2 and hi pwr message (cal curr set to 3.25) and external >> wattmeter shows 19 watts. > > The RF detector seems to be reading low. Check the RF detector > components on the RF board: R66, R67, R68, R69, D9. Make sure the > resistors are the correct values and the diode is the correct type. > > -- > 73, > Vic, K2VCO > Fresno CA > http://www.qsl.net/k2vco > _______________________________________________ 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: K2 TX alignment problems continue
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I have retested and the output as shown on the k2 tracks more closely
with the watt meter. On 40m with the k2 showing 10 watts, I am seeing 2.6 amps. When I push it to the maximum, it shows between 14 and 16 watts depending on the band. I have set cal cur to 3.25amps. When I crank it to full output, after abt 10 seconds I see the mpu reset (drops out of xmit and the elecraft name appears in the lcd). Is this a sign of trouble or some safety logic to keep it out of 'full carrier' mode for long? I have aligned all the bands per the procedure and it acted normally (peaking a decent amount based on the can/capacitor. 73 Neal On Feb 13, 2005, at 9:07 PM, Neal Campbell and Sarah Ferrell wrote: > The good news is that I did a diode dance, had the rf probe diode in > D9, had the real d9 substituted for a 4148 and a 4148 in the rf probe. > > Will swap them around and redo the tests! > > Neal > > On Feb 13, 2005, at 6:00 PM, Vic Rosenthal wrote: > >> Neal Campbell and Sarah Ferrell wrote: >> >>> The symptom of my problem is: >>> 1. when setting k2 power to 5 watts, I get a reading of 2.2 amps >>> with abt 0.8v drop >>> 2. when looking at power output with an external wattmeter, 5 watts >>> reflecting on the external wattmeter shows as 3.8 on the k2. >>> Similarly, 10 watts on external wattmeter is reading 6.9 on the k2 >>> at an 2.8 amps. Cranking the rf power all the way clockwise shows 15 >>> watts on k2 and hi pwr message (cal curr set to 3.25) and external >>> wattmeter shows 19 watts. >> >> The RF detector seems to be reading low. Check the RF detector >> components on the RF board: R66, R67, R68, R69, D9. Make sure the >> resistors are the correct values and the diode is the correct type. >> >> -- >> 73, >> Vic, K2VCO >> Fresno CA >> http://www.qsl.net/k2vco >> > > _______________________________________________ > 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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Neal Campbell and Sarah Ferrell wrote:
> I have retested and the output as shown on the k2 tracks more closely > with the watt meter. On 40m with the k2 showing 10 watts, I am seeing > 2.6 amps. > > When I push it to the maximum, it shows between 14 and 16 watts > depending on the band. This is normal. > I have set cal cur to 3.25amps. When I crank it to full output, after > abt 10 seconds I see the mpu reset (drops out of xmit and the elecraft > name appears in the lcd). Is this a sign of trouble or some safety logic > to keep it out of 'full carrier' mode for long? No, it shouldn't do this. if the CAL CUR setting is exceeded, you will get a Hi Cur indication but the MPU should not reset. What are you using for a power supply? -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco _______________________________________________ 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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The ARRL Handbook says that a cheap way to get a voltage calibration
standard is to use a brand new D cell. It is supposed to have a voltage of 1.56 Volts. Assuming that one wanted to use a set of D cells as a voltage standard (say for checking a DMM), is there a way to store them to minimize the rate at which the voltage runs down? Can one store them in a refrigerator or freezer? Does it do any harm? Does it do any good? 73, Steve Kercel AA4AK _______________________________________________ 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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Steve,
I don't have a direct answer to your question - I do believe that information is old and tha actual voltage depends on the battery type (zinc/carbon, alkalyne, etc), BUT --- Look on my website www.qsl.net/w3fpr for an easy to build calibrator for your DMM. 73, Don W3FPR > -----Original Message----- > > The ARRL Handbook says that a cheap way to get a voltage calibration > standard is to use a brand new D cell. It is supposed to have a > voltage of > 1.56 Volts. Assuming that one wanted to use a set of D cells as a voltage > standard (say for checking a DMM), is there a way to store them > to minimize > the rate at which the voltage runs down? Can one store them in a > refrigerator or freezer? Does it do any harm? Does it do any good? > > 73, > > Steve Kercel > AA4AK > > _______________________________________________ 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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Don:
That is really cool. I'm definitely figuring to build one of those. 73, Steve At 12:35 AM 2/14/2005 -0500, W3FPR - Don Wilhelm wrote: >Steve, > >I don't have a direct answer to your question - I do believe that >information is old and tha actual voltage depends on the battery type >(zinc/carbon, alkalyne, etc), BUT --- >Look on my website www.qsl.net/w3fpr for an easy to build calibrator for >your DMM. > >73, >Don W3FPR > > > -----Original Message----- > > > > The ARRL Handbook says that a cheap way to get a voltage calibration > > standard is to use a brand new D cell. It is supposed to have a > > voltage of > > 1.56 Volts. Assuming that one wanted to use a set of D cells as a voltage > > standard (say for checking a DMM), is there a way to store them > > to minimize > > the rate at which the voltage runs down? Can one store them in a > > refrigerator or freezer? Does it do any harm? Does it do any good? > > > > 73, > > > > Steve Kercel > > AA4AK > > > > _______________________________________________ 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 Don Wilhelm-3
> Look on my website www.qsl.net/w3fpr for an easy to build calibrator for > your DMM. > > 73, > Don W3FPR I looked at Don's neat little project, and really like it. However, I just don't have time to scratch-build right now. Out of curiosity, I did an EBay search for "voltage reference standard" and found a guy named Joe Geller at gellerlabs.com. He sells an assembled calibrator that is NIST traceable when delivered. They start at about $25.00 and go up, but all are under $100. They are available in 2.5, 5, and 10 volt models. If I remember correctly, his claim for accuracy is about 0.1%. For a few dollars more, he will use a chip that doubles that accuracy. I ordered the basic model to test and/or calibrate my used HP 3466A. I will put out a report on how I like it when it gets here! Dan Allen KB4ZVM K2 S/N 1757 _______________________________________________ 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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Maxim has a nice family of references (MAX6126) speced at 0.02% in several
voltage values. It's around $6 but they'll send you a free sample. http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3623 73/Bob - W5BIG =========================================================== ----- Original Message ----- From: "Dan Allen" <[hidden email]> To: <[hidden email]>; "Stephen W. Kercel" <[hidden email]>; "Elecraft Reflector" <[hidden email]> Sent: Monday, February 14, 2005 8:58 PM Subject: Re: [Elecraft] Calibration Standard > > > Look on my website www.qsl.net/w3fpr for an easy to build calibrator for > > your DMM. > > > > 73, > > Don W3FPR > > I looked at Don's neat little project, and really like it. > > However, I just don't have time to scratch-build right now. > > Out of curiosity, I did an EBay search for "voltage reference standard" > found a guy named Joe Geller at gellerlabs.com. He sells an assembled > calibrator that is NIST traceable when delivered. They start at about > $25.00 and go up, but all are under $100. They are available in 2.5, 5, and > 10 volt models. If I remember correctly, his claim for accuracy is about > 0.1%. For a few dollars more, he will use a chip that doubles that > accuracy. > > I ordered the basic model to test and/or calibrate my used HP 3466A. I will > put out a report on how I like it when it gets here! > > Dan Allen > KB4ZVM > K2 S/N 1757 > _______________________________________________ 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 dlajr
Well, I received my 5 volt calibration standard from Joe Geller at
gellerlabs.com today. I upgraded to the KQ chip. The papers with it shows that it is calibrated to +/- 10 microvolts. On a 5 volt scale, that is +/- 2ppm. The initial calibration is then +/- 0.0002%! I connected it to my Alinco DM-330MV switching power supply locked at 13.8 volts. I then tested my Sears Craftsman 82002 autoranging multimeter. It displayed 5.04 volts. That is an error of 4 parts in 500, or 8 parts in 1000, or 0.8%. Next, I tested my HP 3466A bench-top DMM. It displayed 5.000 volts both autoranging and with the range manually set. I bought the HP meter used off of EBay for the purpose of aligning my K2. The K2 has always seemed to be dead on (or spot on as our British friends say), and I guess I now know why! The calibration standard from Joe Geller is a beautiful piece of work. I think it is well worth $25! Dan Allen KB4ZVM K2 S/N 1757 _______________________________________________ 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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A couple of general questions to the reflector regarding voltage meter
calibration: 1) if the meter is spot-on on one scale, can one assume it is so on all scales (or all autoranges)? I suspect the answer is no, but am surely willing to hear the word of those who know. 2) if the meter reads, say, 5.05 when it is measuring 5 volts, giving an absolute error of .05 volts and a relative error of 1%, is it the absolute error or relative error that is relevant. That is, when measuring 100 actual volts, will one get 100.05 or 101 volts (modified, of course, by the issues entailed in question 1)? I suspect the answer is "relative," but again, I would love to get the word from the experts. thanks, dave belsley, w1euy On Feb 18, 2005, at 10:41 PM, Dan Allen wrote: > Well, I received my 5 volt calibration standard from Joe Geller at > gellerlabs.com today. > > I upgraded to the KQ chip. The papers with it shows that it is > calibrated to +/- 10 microvolts. On a 5 volt scale, that is +/- 2ppm. > The initial calibration is then +/- 0.0002%! > > I connected it to my Alinco DM-330MV switching power supply locked at > 13.8 volts. > > I then tested my Sears Craftsman 82002 autoranging multimeter. It > displayed 5.04 volts. That is an error of 4 parts in 500, or 8 parts > in 1000, or 0.8%. > > Next, I tested my HP 3466A bench-top DMM. It displayed 5.000 volts > both autoranging and with the range manually set. > > I bought the HP meter used off of EBay for the purpose of aligning my > K2. The K2 has always seemed to be dead on (or spot on as our British > friends say), and I guess I now know why! > > The calibration standard from Joe Geller is a beautiful piece of work. > I think it is well worth $25! > > Dan Allen > KB4ZVM > K2 S/N 1757 > > _______________________________________________ > 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 dlajr
I have a like new K2 serial no. 349X for sale. It included the KSB2 and KAT2
adapters and all paperwork. It works great! I want to build another and that is why I am selling. This is the second I have built. I am a retired electronics instructor and have built many, many kits and homebrew items. It is very well built and works great. $825 shipped in the US. Richard Cash W4UGM (864) 463-4205 _______________________________________________ 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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