[Elecraft] Elecraft K2/100 lives!!!
After more than 6 years off and on (more off, than on), Elecraft K2/100 s/n 4276 lives!!! The final test was FD 2010 operating from the Uncle Bill's Radio Club for Kids (UBRCK) field day site, under callsign NJ1E. The rig successfully logged more than 35+ contacts under the hand of several kids who were being exposed to Ham Radio for the first time. Needless to say, we weren't going for score. Just to have fun. Slade Smith KC4WVL PeoplePC Online A better way to Internet http://www.peoplepc.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
[Elecraft] K2 Transmitter Power Issue, K2 s/n 4276
K2 s/n 4276 Firmware Revision(s): 2.04P 1.09 Finally had time to open up the rig and check the soldering and check the placement of the components on the back of the control board. Still no change. When transmitting, again the power output fluctuates rapidly and the current draw fluctuates as well. Help! 73 de KC4WVL William Smith - Original Message - From: "Don Wilhelm" To: "kc4wvl" Cc: Sent: Tuesday, December 11, 2007 17:01 Subject: Re: [Elecraft] K2 Transmitter Power Issue > William, > > Check the soldering carefully, particularly on the Control Board. Also > check and re-check the placement of the components mounted on the back > of the Control Board (they are part of the power control circuits). > > Check soldering, then re-check the soldering, and when that is finished, > check the soldering. > > Good luck in finding it. > 73, > Don W3FPR > > kc4wvl wrote: > > K2 s/n 4276 > > Firmware Revision(s): 2.04P 1.09 > > > > I am having a problem with output power stability. Example: Power set to 5 watts. When transmitting (into a dummy load), power out is all over the place, from as low as .2 watts to as high as 12 watts. This fluctuation is very rapid. Measured current (at the P/S) fluctuates with the power output fluctuation. > > > > Can anyone give me an indication of any possible cause and solution? > > > > Thanks. > > > > 73's de KC4WVL > > William Smith > > > > ___ > > Elecraft mailing list > > Post to: Elecraft@mailman.qth.net > > 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 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
[Elecraft] K2 Transmitter Power Issue
K2 s/n 4276 Firmware Revision(s): 2.04P 1.09 I am having a problem with output power stability. Example: Power set to 5 watts. When transmitting (into a dummy load), power out is all over the place, from as low as .2 watts to as high as 12 watts. This fluctuation is very rapid. Measured current (at the P/S) fluctuates with the power output fluctuation. Can anyone give me an indication of any possible cause and solution? Thanks. 73's de KC4WVL William Smith ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K2 s/n 4276 Output Power Instability
K2 s/n 4276 Firmware Revision(s): 2.04P 1.09 After having a previous issue with the VCO alignment (p. 61), construction went forward without a hitch. At this point, I figured that any gremlins had been banished. Not so. Another pesky gremlin has reared it's ugly head. During transmitter alignment, the initial 40 meter alignment went down in accordance with the manual's expectations. Receiver pre-alignment was straight forward. Alignment of 20 and 30 meter transmit went fine, then from that point on, it all went downhill and the current issue began. Regardless of which band or power setting, on entering TUNE, the power out readings rapidly vary across the entire scale. These rapidly changing readings are also reflected on my Diamond SK-600 power/SWR meter as well as the readigs on the current meter of the power supply. After a brief bit of time, the power out will sometimes stop fluctuating and settle down to the requested power setting. Might this be a problem with U-6, on the control board? I would appreciate any insight of the possible cause of this issue and suggestions of any possible sollutions. 73's William Smith KC4WVL ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] s/n 4276 VCO Alignment issue: SOLVED
K2 s/n 4276 Original Issue: Reported in March 2003. "VCO Alignment (p61) VFO set at 4000 kHz @R30 left side = 0.018 vdc L30 verified as a 4.7 uH "T005Z" C72 verified as a 270 pF "271" Rewound T5 verified primary = 16 turns verified secondary = 4 Adjusting L30 has no effect on R30 voltage reading." * VCO Alignment issue solved!! Family responsibilities had the project in the shelf for over 2 years. I finally was able to continue construction this past summer. I discovered after studying the circuit diagram and other details that I had a possible problem with U6. Specifically with U6B. When checking inputs and outputs, U6A's inputs and output were all as the DC Voltage Tables predicted. On the otherhand, U6B had good inputs but the output was almost non-extistant. After checking other components (that could be loading down the circuit). As my K2 is no longer under warranty, I made a quick call to Mouser and a few days later, I had a replacement part in hand. After installation, L30 now adjusts the voltage reading at R30. Construction then proceeded at a rapid pace, such that all that is left is final alignment and test. Amazing how a 40 cent part can stop the train in it's tracks. As I have the KPA100, construction has begun and proceeds at a steady pace. Thanks to all those who responded to my original request for help. :-) 73's William Smith KC4WVL ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: s/n 4276 VCO Alignment issue
K2 s/n 4276 VCO Alignment (p61) VFO set at 4000 kHz L30 verified as a 4.7 uH "T005Z" Adjusting L30 has no effect on R30 voltage reading. * At TP3, there is a 12100.93 kHz signal present. At TP1, there is a 7717.86 kHz signal present. R30 is only 0.019v Visually inspected all components, verified that all are the correct values and no components are installed backwards. Solder joints look ok. No solder bridges or un-soldered connections found. Changing bands does not change the reading at R30. Visually inspected D16 and D17, both appear OK. RFC15 is 8.5 ohms U6-1 during PLL test, goes from 0.006v to 7.63v U6-5 is steady at 4.004v RFC14 leads look good and has 10 turns. RFC15, C91 and C88 reinspected and appear ok. T5 looks like the photo. Tried spreading and compressing the windings. No change in voltage readings at R30. Other measurements: U6-1 = 7.65v U6-5 = 4.004v U6-6 = 4.88v U6-7 = 0.019v U6-8 = 8.05v U4-16 = 4.88v Please advise. Thank You William Smith KC4WVL ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] VCO Alignment issue
K2 s/n 4276 VCO Alignment (p61) VFO set at 4000 kHz @R30 left side = 0.018 vdc L30 verified as a 4.7 uH "T005Z" C72 verified as a 270 pF "271" Rewound T5 verified primary = 16 turns verified secondary = 4 Adjusting L30 has no effect on R30 voltage reading. Please advise. Thank You William Smith KC4WVL ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
