Re: [Elecraft] ALC issue - K3s
Dick, If you use the AUX cable between the K3S and the KPA500, check the ALC THR setting on the KPA500 to be sure its ALC threshold level is not set too low. Have you tried running the K3S directly into a dummy load to see if the ALC behavior is the same as what you've observed (or run the KPA500 in STBY mode to bypass its PA)? Just wondering if the issue arises in the KPA500 ALC feedback to the K3S rather than directly in the K3S itself? Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3S Fault
The lack of output power on both 10 and 12 meters suggests a problem in either the lowpass filter (post-PA) or bandpass filter (pre-low power PA), which in both instances is common to those two bands. I would check relay activations on the input and output sides of both the BPF and LPF 10/12 meter filter sections to be sure that those filters are being selected. You should try to listen on 10 and 12 meters if you have an external signal source (signal generator or another transmitter into a dummy load with a length of wire for a RX antenna near the dummy load) for those bands - are you able to hear a test signal? And the most obvious suggestion, which I would check first: do you have the proper antenna port selected on the front panel? (ANT 1 or ANT 2) The antenna port selection is band-specific. Presumably, the proper antenna port was selected for the dummy load test you ran? 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2/100 up-date
Art, Don, W3FPR used to do much of this work on K2 transceivers, but he has retired from that role. Dave, W8FGU has assumed Don's role. Alan, W3DVX also provides such services. Both have posted periodically to this forum. There may be others who are experienced K2 upgraders, but these are the folks that come to mind. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] KSB2 problems in K2 transceiver
Mark, Pin 5 of U2 provides ALC threshold voltage to the emitter of Q1 on the KSB2 board. The 5.89 V you measured on Pin 5 suggests that the DAC input register B didn't properly load the data word from the MCU. I would check the solder joints on all U2 pins and Pins 14, 16 and 17 of the MCU socket. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 parts
Check here - options are half-deposit and full deposit. https://elecraft.com/pages/k3-k3s-options 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Testing
Don, I've observed that the rate of new posts has gone down (no scientific estimate, just a gut sense based on daily checks of the forum). I have no speculation as to why. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 upgrade notes not found on Elecraft site...
Chuck, I found an old copy of the K2 firmware update instructions with brief descriptions of prior versions' feature changes using the Wayback Machine (aka archive.org). https://web.archive.org/web/20090822034804/http://elecraft.com/ Once at this archived page, select Manuals and Downloads in the left hand menu, select K2 manuals, and scroll down to the link titled "2.04 K2 Firmware Notes." That lists the features of the Rev 2 firmware succession. The most recent firmware version, I believe, is 2.04R. The instructions for this version have a more limited history of changes. https://web.archive.org/web/20150905061319/http://www.elecraft.com/manual/K2_Rev_2_FW_Rev_J.pdf I hope this helps a bit more........ Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 upgrade notes not found on Elecraft site...
Does this link get you there? https://elecraft.com/pages/k2-mods-and-notes I did not find a list of features incorporated in the various firmware updates. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Sudden loss of K3 RX sensitivity
I must correct my earlier post on Pete's question - faulty memory on my part regarding the actual failed part in LA7NO's K3 T/R switch. It was NOT the PIN diode D25, but was instead the RF choke (RFC30) that provides the DC path to ground that enables the 7T or 7R control voltages to select the signal path through D25. That choke failed open. Mea culpa, and 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] KIO2 Not Working
Richard, What kind of cable did you use to connect the K2's KIO2 RS-232 port to the transverter? As Don, W3FPR has reminded us numerous times, one cannot use a conventional RS-232 (straight thru serial) cable with the KIO2, but one must instead make up the special cable described in the KIO2 manual. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Sudden loss of K3 RX sensitivity
Pete, There was a similar report on the forum last year from Per-Tore, LA7NO. In an extended email conversation we deduced his problems were caused by failed PIN diodes in one of the T/R switches, which ultimately proved to be the case. His K3 also lost TX power, unlike your situation, so you may have lost only the PIN diode in the RX path. There were many other possible causes suggested by others on the forum around that time (late July 2020) - you might read that thread and try the simple fixes first (e.g., twist and re-seat the TMP connectors) before delving into circuit/component failure possibilities. The old thread is here: http://elecraft.365791.n2.nabble.com/Elecraft-K3-problem-td7663573.html#a7663581 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Mr. Mike, Be sure you have the KAT3 internal ATU "enabled" and not bypassed, be sure the proper antenna is selected (ANT 1 or ANT 2) for your random wire, and press (momentary) the ATU TUNE button. The relays will clatter a bit, and you'll see the displayed SWR ratcheting down, maybe up for short time, as a tuning solution is searched. If the SWR isn't low enough for your tastes, press the ATU TUNE button again within 5 seconds of the conclusion of the previous attempt's end, and the ATU will try again, often with slightly improved result. Don't be surprised if you experience RF gremlins in your shack with a random length wire without a counterpoise. Mike, K8CN (hoping to be back at NEAR-Fest next year!) -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3s Not Receiving 80m
Check your RX ANT settings to be sure that you haven't inadvertently selected a non-existent RX antenna. (see bottom paragraph of page 70 in the K3s User Manual). Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] OT - Yagi and OCFD vertical separation
I'll add to Don's guidance this question: If you're NOT using the OCFD for receiving concurrently while transmitting on the Yagi, are you concerned about interaction of the two antennas with regard to pattern distortion of the Yagi by currents induced in the OCFD? If so, then you need a few wavelengths separation at the frequency of interest (20 meters being the lowest frequency for the Yagi). If you don't care about the Yagi's pattern distortion, then don't worry about the separation distance. Many folks hang inverted V antennas for the low bands from the same tower on which Yagis are mounted, often just a few feet down from the Yagi. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 issue or is it?
Barry, can you provide more detail about the K2 settings when you hear the snapping sounds? For example, does this effect occur only in CW mode, or in USB and LSB modes as well? For which filter settings does it occur (both CW and SSB filter settings)? Is your AGC turned ON or OFF? Does the snapping subside if the RF (actually IF) gain is backed off? Does the snapping subside if the AF gain is backed off? Does this phenomenon occur on all bands or just a few bands? Don, W3FPR, will likely have a few possible causes immediately in mind after repairing hundreds of K2 radios over the years! 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3 Problem
Hi Per-Tore, Can you identify which transistor (or other device) on the LPA module is getting hot in transmit mode? The drain terminals of MOSFET PA transistors Q4 and Q5 receive +12V regardless of TX or RX mode, but the gate bias voltages are applied only in TX mode. Unless there's a problem with the bias regulator circuit (U1), the RF amplifier chain on the LPA module should not be getting that warm. It is also possible that one of the RF power transistors may be getting hot because it is no longer making good thermal contact with the bottom cover panel - it would be good to check the tightness of the three screws holding those transistors against the bottom panel. Is it possible for you to carefully extract the LPA module from the main RF board? That requires removal of the rear panel of the bottom cover, and you may need new thermal pads for the RF transistors if those pads are damaged by removal of the cover panel. If you can remove the LPA module, you might try RX mode ONLY with the Power control set to 0 (to ensure that the KPA3 PA is bypassed by its relay K1) and see if your receive sensitivity is restored. The output side of the LPA module is nominally connected only in TX mode to the antenna path via diode D1 on the LPA module, and if the D1 switch is operating properly one would not expect the high attenuation of signals in RX mode. The output of the LPA module is also connected to the input of the 100 W PA module at the same point on the T/R switch circuit, but that module is bypassed by relay K1 on the KPAIO3 board. I'm not yet sure how the overheating of a device on the LPA board is connected to the loss of RX sensitivity. If the diode switch D1 on the LPA module has failed shorted (unlikely), then it would leave the output circuitry of the LPA module bridged across the antenna signal path in RX mode. Keep us posted on what you learn! 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3 problem
Aye, Wes, indeed you did! I wasn't thinking of LO drive levels when I first read your post, but was thinking of common signal paths for TX and RX through the T/R switch and no deeper into the signal processing chain. Let's hope your and Martin's suggestion proves to be the true cause of Per-Tore's issue. Thanks, and 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3 problem
I agree with Martin's simpler hypothesis. The sudden change of behavior in both TX and RX modes could well result from insufficient LO drive to either the 1st or 2nd mixers. Check that possibility before launching into detailed testing of the PIN diode T/R switch. It may be as simple as a loose or corroded TMP connector. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3 problem
Hi Per-Tore, I don't know if there's an easy way to check the PIN diodes in the T/R switch, especially since the SMD components of the switch are mostly on the underside of the RF board. Here's where I would start: 1) Find spots on the RF board (top side) where you can measure the control voltages 7R and 7T. Verify that these change in opposition to each other, i.e. if 7R is high, 7T should be low and vice-versa, when changing from RX mode to TX mode and back. 2) Presuming that both voltages 7R and 7T behave properly in switching from RX to TX mode and back, I would measure the voltage on the drain of Q7, the MOSFET switch, when 7R is high. Assertion of 7R should pull the Q7 drain voltage low, which causes sufficient current to pass through both PIN diodes D26 and D27 to enable the RX signal to pass through, presuming there is not a problem with PIN diode D25. 3) It is possible that the Q7 drain voltage could be pulled low if only one of PIN diodes D26 or D27 functions properly and the other has failed open, so test (2) is not conclusive. 4) If you have a scope with a 10X probe, I would check for presence of RF on the anode of PIN diode D43 when in TX mode - any frequency on the VFO within the scope bandwidth should suffice. D43 must be forward-biased by the 7T voltage in order for RF drive to be coupled to the low power (10 Watt) PA assembly (Z2 on the block diagram). The fact that you have not been able to detect any transmitted power in TX mode whether the 100 watt PA is bypassed or not may indicate that the low power PA is not receiving drive from the mixer. The 7T voltage is supplied to the anode of D43 via the low power PA input connector, but it's unlikely that the simple path internal to the low power PA board is at fault, i.e. 7T is not reaching D43. I haven't had my K3 opened up for many years, nor have I experienced the problem you described, so I can't easily point out where to access the circuit points mentioned above. There is another set of PIN diode switches around the mixer, but I would start with those closest to the low power PA before going further back up the signal processing chain. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3 problem
You might check the PIN diode T/R switch. The high attenuation in RX mode and no output power even when the 100 W PA is bypassed suggest that one or more of the PIN diodes in the T/R switch have failed "open." Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Electrolytic Capacitor failure
Ray, I reported to this forum (ca. February 2019) a similar, though not identical, problem involving my K3/10 while running from an Astron RS-20A supply. My problem occurred in receive mode rather than transmit mode, which made it a bit more difficult to understand because the current demand for my K3 in receive mode is less than 1 A. After finding no problem using an alternate supply (Astron SS-30 or 12 V battery), I ripped my RS-20A apart to test the various parts on either side of the regulator board. To keep a long story short, the problem turned out to be the large electrolytic filter capacitor at the output of the rectifier block (ahead of the regulator board). It had no external signs of leakage or bulging, but its ESR (equivalent series resistance) had risen to perhaps 2-3 ohms. Finding it hard to believe this ESR could present the DC voltage and current oscillations I observed, I did a SPICE simulation of the transformer/rectifier/filter capacitor circuit with a load designed to draw about 1 A. A good capacitor (ESR = 0.05 ohms) showed hardly any DC voltage ripple, whereas the capacitor with 3 ohms ESR showed huge ripple. I didn't get a chance to put a scope on the actual RS-20A regulator input to confirm the simulation result, but it appears that the regulator circuit developed a low-frequency limit cycle oscillation when loaded by the K3/10 at 1 A current, likely due to the high amplitude voltage ripple at the regulator input caused by the elevated ESR of the filter capacitor. The DC bus voltage reported by the K3 toggled between two values, 13.6 V and 12.7 V. Motto of this story: even if an electrolytic doesn't appear bad externally, suspect increased ESR and replace it. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] S6 noise floor?
As others have noted, ferrites will help attenuate RFI ** IF ** you own the offending source and can choke it for radiation or choke your own wiring against common-mode pickup. However, I find that RFI generators over which I have no control are the predominant sources at my QTH after all the local offenders are quenched, e.g. arcs on tie wires or transformer connections in the electricity distribution wiring in my neighborhood and beyond, and RF egress from defected coax sheaths in the cable distribution network. Interestingly, the local power company RFI hunter told me that he works hand in glove with the cable companies because the cable customers report TV, internet and telephone interference that is traced to power line arc generators making ingress to the cable network - both utilities find the weak points in their respective systems. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] [K3] Spontaneous HI CUR, audio reduction in RX mode - UPDATE
I may have found the cause of the anomalous HI CUR warning in **receive** mode, thanks to my big orange Maine coon cat, Mr. Opie. In rubbing his chin on the VFO B knob while I was listening last night, he rotated the control to the 12V DC bus voltage display, which I then noticed was oscillating between 13.6 V and 12.7 V. When I checked the DC bus current display, it was oscillating between 0.4 A and 2.1 A - clearly something was amiss. Tonight I checked the terminal voltage on my Astron RS20-A linear supply, and found it to be stable at 13.7 V with no load (K3 turned off), but then it dropped to 13.4 V with the K3 'on' in receive mode. I again checked the K3's internal volt/ammeter readings and found the same periodic oscillation in each one. Curious to know if the oscillation was due to an interaction with the supply regulator, I swapped out the RS20-A for my Astron SS-30 SMPS, which I normally use with my K2/100 setup. Lo and behold, the DC bus oscillations ceased! I have not yet spent enough time listening using the alternate power supply to know if the HI CUR warnings will also cease, but will do so over the coming week. Fortunately, I don't have to watch the K3 display because the HI CUR condition also reduces headphone audio substantially, which gets my immediate attention. Kudos to Mr. Opie for his uncanny sense of what might reveal a potential cause of the spontaneous HI CUR warnings in receive mode. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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
Re: [Elecraft] K3 Erratic Power Output
Larry, there's a good chance that the SWR bridge (FWD/REFL power measurement) on the K3 RF Board has a problem with the level scaling feature that switches on when you command a transmit power level above 12 watts. Check the K3 RF Board schematic (here I'm presuming you have the K3 rather than the K3S, but I think the SWR bridge circuits are similar), page 4 of the schematic package, on the far right hand side for the SWR bridge circuit. Near the LM358 op amp voltage followers (outputs labeled VFWD and VREFL) you'll see a pair of voltage dividers that are enabled by logic signals /FSCL and /RSCL for higher output power levels. I'm going out on a limb here, but if /FSCL is not grounded when you command an output power greater than 12 watts, the voltage follower on the FWD power branch may saturate and effectively remove the feedback signal that the power control loop requires to operate properly. The /FSCL signal is generated at the output of one flip-flop in an 8-bit shift register - if that output won't pull down to ground R53, the lower arm of the voltage divider in the FWD power level scaling circuit, that may inhibit the necessary scaling of input voltage to the follower to keep it from saturating. The fact that the power control loop appears to work smoothly at commanded power levels less than the 13 watts indicates that the SWR bridge rectifier diodes are still functioning properly. The jump to more than 100 watts output when you command a power level just slightly greater than 13 watts tells me the power control loop is getting different FWD power information than what it expects to see. Probing the SMD device leads to check that /FSCL is properly asserted when you cross the 12 watt threshold? I'll leave that one to the pros! 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode
Thanks, Keith, for the pointer on audio IC U1 on the DSP board. Visual inspection shows no obvious sign of overheating on the IC or the DSP board itself. Will have to find a thermometer with a fine tip probe to measure surface temperature on U1 though - household thermometers I have are too large to fit into that space. 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode
With thanks to Björn SM7IUN and Mike VP8NO for pointing me to the firmware revision notes, I checked my installed firmware and the K3 Utility and find them to be fully up to date. I'll go quiet on this issue until I've had a chance to reload the firmware and open the case to explore the board connectors. I appreciate the guidance from those with better memories of firmware revision notes! 73, Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode
I believe I found a potential answer in the K3 manual (to my embarrassment, I should have looked there first, eh?) under the Troubleshooting section, Receive mode: "HI CUR or SPKRS=1 warning: HI CUR may indicate a shorted left speaker channel; the K3 will reduce AF gain." Funny thing is that I don't use the internal speaker, just headphones connected via the rear panel PHONES jack, and have never plugged anything into the external speaker jack...I guess I'll unbutton the case and see if any wiring is awry. The intermittency of the HI CUR warning in receive mode is puzzling - if there's a shorted audio channel, I would think it would stay shorted unless my headphones have an intermittent short on one side. Thanks, too, to Joe, 4Z7JBA, for his offline suggestion of another potential cause for the observed behavior in receive mode. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
[Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode
Over the past several weeks, and especially during the NA Sprint CW contest last Saturday night, I've noticed spontaneous brief flashing of the HI CURR warning *in receive mode*, which is accompanied by an immediate reduction in headphone audio (though not complete loss of audio). It is as though the receiver's RF attenuator was switched in after the HI CURR warning was flashed. My K3/10 is up to date on all firmware and has a serial number in the 66XX range if I recall properly. I have yet to discern any correlation with transmit mode behavior, which has never displayed a HI CURR warning. My gut instinct is that this may be one of those pin corrosion symptoms, especially since I've had some strange responses to front panel button presses that are not repeatable. The receive audio seems to come back, but I can't tell why or when in relation to anything I've done with the radio controls Has anyone else seen the HI CURR warning displayed only in receive mode with accompanying loss of receive signal strength? I've searched the archives and found plenty of discussion about HI CURR warnings, but nothing quite matches my K3's observed behavior in receive mode. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] CW AGC settings
Don, W3FPR wrote a succinct tutorial about AGC settings on his web page www.w3fpr.com under the title "Noisy" K3. I had left my AGC settings for CW contesting at the default values until reading Don's guidance, and once I reset the AGC threshold and slope parameters I had much better CW contesting experiences. Mike, K8CN -- Sent from: http://elecraft.365791.n2.nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Uninterruptible Power Supply for K3S (power line arc noise)
John,
Power line arc noise can happen anywhere, even in a semi-rural area like
your neighborhood (I used to live in Acton MA). There are many web
resources for learning how to identify and track down power line arc
sources. Here are some things I've learned by hard experience.
A good, though not infallible, indication of a power line arc source for
your noise is to check the bands during or shortly after a rain storm. Most
arc sources are quenched temporarily by rain if they're exposed to the
elements. When I first began tracking down noise sources at my QTH several
years ago, I found that keeping a log of baseline noise levels (using the
S-meter indication with the K3 in AM mode, widest filter you have) on all
bands versus time of day and weather conditions was helpful in establishing
any correlation with precipitation or neighbors' activities. I would also
add comments about the qualitative audio signature of the noise ("buzz",
"raspy", "intermittent buzz" - you get the idea).
Simple preliminary source location techniques (once you've eliminated
anything in your own home or yard) include using the AM radio in your car on
a careful drive around your neighborhood to find candidate sources. This is
not particularly selective - you'll hear other interferers in addition to
true arc sources, and you'll want to tune to an unoccupied AM channel - I
use channels high in the AM broadcast band.
My preferred method once I've identified some candidate arc source sites is
to use an inexpensive handheld VHF/UHF scanner with a rubber-duck antenna
and a switchable attenuator. You don't need a fancy lab-grade attenuator -
I find that a home-made 6 dB or 20 dB fixed resistor attenuator (50 ohm,
shielded box) is sufficient. I tune the scanner to an open channel in the
aircraft band (around 135 MHz; it automatically switches to AM detection in
that band, which is necessary to do direction-finding based on signal
strength - FM detection won't work), and walk around the suspect site. Turn
off the squelch completely and set the audio gain at a fixed, comfortable
listening level (I use open-ear headphones for safety as I walk on roads).
I hold the rubber-duck antenna in the horizontal orientation and sweep it in
an arc to either side of my body. The rubber-duck has a pattern null off
the ends, and the reduction in audible noise is very evident if you're close
to the arc source. You can resolve the 180 degree direction ambiguity of
the null by using your body as an additional shielding attenuator - the
difference in audio levels is your clue as to which null direction is the
true one. You will find that you'll need to insert one of the fixed
attenuators between the rubber-duck and the scanner antenna port if you're
very close to the arc source - otherwise it will be difficult to perceive a
null. I've used this technique successfully to locate multiple arc sources
in my own neighborhood over the past few years. The one drawback is that one
cannot hear the arc noise at VHF if one is more than a couple hundred yards
from the arc source unless you use a small handheld Yagi antenna. It's easy
to make a 3 element Yagi for VHF - there are several simple, inexpensive
designs out there to be found.
As Jim, K9YC will likely point out, you may also be hearing switch-mode
power converters that have a much different noise signature than arc noise.
If you can borrow a P3 panadapter from a nearby friend, it is an excellent
tool for distinguishing types of noise. There are many other RF noise
emitters - look at the archives of the Elecraft forum for some examples -
the list of offending devices is too long to include here.
One can, of course, purchase commercial DF'ing units that offer more
features. However, you may already have the basic DF'ing tools in hand, or
you may borrow them from a local ham until you find that you have a
recurring need for this set of tools.
It's likely that your local electric utility has a person trained in finding
arc noise sources, but they love it when you can identify the specific pole
on which you have found the likely source!
73,
Mike, K8CN
Durham NH
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Re: [Elecraft] K2 #7261 receive 20m
Hi Don, Does the slow recovery problem occur only on 20 meters, or is it present on every band? Does the problem still exist if you turn the AGC totally off? 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-7261-receive-20m-tp7592031p7592033.html Sent from the Elecraft mailing list archive at Nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K2 filters?
Gavin, The K2 uses a single voltage-variable capacitance (varicap) diode-tuned crystal filter on the main RF board, and the filter bandwidths are programmable by the user within a moderate range. A separate fixed bandwidth crystal filter is present on the KSB2 SSB option board if installed. A "no additional equipment" procedure for adjusting the variable bandwidth filter is described in the K2 manual, but most operators use a computer-based spectrum analysis tool (e.g. Spectrogram) to visualize the filter passband while the tuning adjustment is being made. Check out Don, W3FPR's web page (http://w3fpr.com/) for a link to the free versions of Spectrogram and tips on adjusting the K2 filter settings for different modes and desired bandwidths. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Elecraft-K2-filters-tp7589831p7589832.html Sent from the Elecraft mailing list archive at Nabble.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Dual Pass Band
Lee, Ed, W0YK, has a commentary on this very subject in the current issue of NCJ (subscription required). Perhaps he will weigh in directly here, but his recommendation was to use the normal filter rather than dual passband. This is not an issue unique to the K3. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Dual-Pass-Band-tp7582564p7582570.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Antenna and battery for KX1
Hi Phil, Shorten the radiator to 44 feet, but leave the counterpoise alone for now. The 65 foot length is nearly a perfect half-wave on 40 meters and will present a very high impedance, possibly beyond the range of your tuner. The shortening won't help you on 80 meters, but if you can lengthen the radiator to 88 feet you'll be in better shape for 80 meters. Is your counterpoise on the ground or elevated? Do you have additional coax to the radiator or just run the wire directly to your KX1? 73, Mike, K8CN Durham NH -- View this message in context: http://elecraft.365791.n2.nabble.com/Antenna-and-battery-for-KX1-tp7577712p7577713.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K3 #7554 dead, please help!
Martin, I presume you have also finished building a K2 since you posted in response to Stan, AE7UT's earlier comment about his K2's receive sensitivity? Did you perform all of the preliminary alignment steps in the "Alignment and Test, Part II" that should yield a working 40 meter receiver? Please clarify where you are in the overall test procedures for the K2. Thanks, and 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-7446-is-alive-and-made-my-first-QSO-tp7576940p7576950.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 almost deaf on 40 meters only
Hi Stan, You didn't indicate other options besides the DSP module that are installed in your K2, but here are some possible gremlins in order of decreasing likelihood of being the culprit: 1) Check the ATT/PRE switch when on 40 meters to be sure the ATT is not switched on. 2a) If you have the KAT2 auto-tuner installed, check the ANT1/2 switch to be sure you have not inadvertently selected the wrong antenna port for your 40 meter antenna. 2b) Presuming that cause #2 is not the culprit, tune the auto-tuner while the K2 is on 40 meters and connected to a good 50 ohm dummy load. Disconnect the dummy load and repeat the XG3 test. (Alternatively, you could place the KAT2 into Bypass mode - see the KAT2 manual for details) 3) If you have the K160RX module installed, go into the MENU and select the RANT parameter while you're on 40 meters - verify that RANT is "OFF". 4) Although very unlikely, one of the filter components or a relay in the 40 meter lowpass or bandpass filter sections may have a bad solder joint that finally was jostled loose in the last week. You can follow the signal tracing directions in the K2 manual if you've exhausted possibilities #1 - #3 above and need to check for an actual physical disconnection on the RF board. I'm curious to know of your findings.. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-almost-deaf-on-40-meters-only-tp7576624p7576625.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Ham fests
Gary, The ARRL maintains a hamfest database which is searchable by U.S. state, ZIP code, ARRL Section and Division, and date range: http://www.arrl.org/hamfests/search CQ Magazine also has a listing, but apparently not in a searchable format: http://www.cq-amateur-radio.com/cq_hamfest_events. QRZ.com maintains a forum devoted to hamfests, which is also searchable: http://forums.qrz.com/forumdisplay.php?12-Hamfest-and-Convention-Calendar Not all hamfest-sponsoring organizations list with one of the entities noted, and there may be other lists of which I'm unaware. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Ham-fests-tp7576478p7576480.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] [K2] Diode types for connecting both paddle & straight key
Steve, Virtually any diodes should work in this setting. If you have volts of RF on your straight key/paddle/computer keying lines, the change to a conventional silicon diode with its slightly higher offset voltage won't give you any freedom from false triggering. Are you experiencing RF feedback issues with your existing setup? I've used 1N4148 diodes in my K2/10 computer keying line without problem for several years, but that's only because I had an abundance of them in my parts bin. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-Diode-types-for-connecting-both-paddle-straight-key-tp7575425p7575474.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 Resistance Checks
Tom, You're not the first to encounter this particular anomaly. Don, W3FPR had these suggestions for another builder, the link to which I've included below. http://elecraft.365791.n2.nabble.com/K2-RF-Board-resistance-check-failure-U6-Pin-8-tt7559095.html#a7559102 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-Resistance-Checks-tp7573139p7573141.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Low P, 160M only
Jeremy, Is the problem you cited a recent change in the behavior of your K2? Also, do you have the KAT2 installed? Since the problem occurs on 160 meters only, and even when using a dummy load, I wonder if the 80 meter/160 meter alignment procedure (see K160RX manual) needs to be repeated? The Lo P message could be displayed if you accidentally placed the K2 into "Test" mode, i.e. disabled the transmitter, then attempted to key the rig, but this would also be apparent on other bands too. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Low-P-160M-only-tp7572970p7572978.html Sent from the Elecraft mailing list archive at Nabble.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] [OT] Obsolescence of serial ports
Those who've dealt with issues in USB to serial port conversion will appreciate Bill Wong's commentary in Electronic Design: http://electronicdesign.com/blog/s-obsolete-not 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/OT-Obsolescence-of-serial-ports-tp7572401.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Elecraft FTP server unreachable?
Problem resolved! Turned out to be an overly aggressive firewall in a router on my home network, about which I had forgotten since I set it up years ago. Loosened the screws on the firewall temporarily, successfully upgraded K3 firmware, and battened the hatches again once done. The K3 Utility help file did mention a possible need to "negotiate" with the firewall in the event of an FTP timeout, but I was originally thinking only of the firewall on the host PC for the K3. Just wanted to report back in case others should encounter a similar difficulty. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Elecraft-FTP-server-unreachable-tp7569154p7569171.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Elecraft FTP server unreachable?
Thanks for checking, Knut. I had used that URL. When I ping it, there's no response here either. Guess I'll do more local diagnostics.. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Elecraft-FTP-server-unreachable-tp7569154p7569159.html Sent from the Elecraft mailing list archive at Nabble.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] Elecraft FTP server unreachable?
I've tried accessing the FTP server for a firmware upgrade via the K3 Utility, Firefox, and IE, but no response. I checked my firewall settings to be sure the FTP server is a trusted site, but still no connection. What have I overlooked? 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Elecraft-FTP-server-unreachable-tp7569154.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] [K2] POWER control has no effect on actual transmit power
Ben, It sounds like re-heating of the solder connections on both sides of C121 is in order. The fact that your RF voltage on terminal 3 of T1 has the proper ratio to that on terminal 1 implies that T1's solder joints are OK. The absence of RF on the driver (Q6 base circuit) side of C121 could be due to a very low impedance being presented there, but this would have been reflected in a much lower voltage reading at terminal 3 of T1 ** if ** C121 was properly connected. I would hesitate to operate the transmitter without the heat sink attached even for brief periods of time. Good luck, and 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-POWER-control-has-no-effect-on-actual-transmit-power-tp7564692p7564709.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2: Modulation on CW signal
Hi Christophe, The VCO shield kit may be found here: http://www.elecraft.com/order_form_parts.htm#K2%20Parts Look at the first line labeled K2VCOSHLDKT. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-Modulation-on-CW-signal-tp7564439p7564518.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] resistances test K2
Hi Christophe, Your resistance values are fine. These control board resistance checks are intended to reveal low resistance paths that should not be present (for example, solder bridges), and your measured values are far from short circuits! Enjoy the building of your K2. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/resistances-test-K2-tp7564509p7564517.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] k3 filter install
James, The full procedure is a bit long for an email, but please see page 46 in the current version of the K3 Owners Manual, which is available under Manuals and Downloads at the Elecraft web page. All of the filter setup functions are accessed through the CONFIG menus. There are 3 key steps to follow: (1) Tell the K3 where to find the new filter (slot FLx), its bandwidth and its frequency offset; for the 8 pole filters such as your KFL3A-400 there is 0.00 frequency offset, (2) Enable the filter for receive mode, and (3) Activate filter loss compensation (typically 1-2 dB for the 400 Hz 8-pole filter). You shouldn't need to alter the Transmit Crystal Filter Selection settings if you have already done this procedure with the stock 2.7 kHz 5-pole filter. Enjoy the new filter! 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/k3-filter-install-tp7563719p7563779.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Detection ob BY-1 Iambic Keyer with K2
Hi OM, I presume you're using the BY-1 alone without an external keyer? If so, tap the K2's MENU button, scroll through the Main Menu options until you reach INP (for the key/paddle INPut), then hold EDIT (same button), then select PDLn if your paddle is wired "normally." Tap the MENU button twice to exit the configuration mode. Use PDLr if dot/dash sides are reversed from what you expect. See page 99 of the K2's Rev. I manual for more detail. Hope this helps! 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Detection-ob-BY-1-Iambic-Keyer-with-K2-tp7563519p7563529.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] KAT2 high SWR problem..?
Gil, When you say you completed your KAT2 build, did you complete all of the final calibration steps, specifically the bridge null adjustment (p. 16 of the KAT2 manual) and the power calibration adjustment (p. 17)? I would be surprised if you could make those adjustments successfully and yet have the low output power you indicated into a good 50 ohm dummy load - a problem with T1 connections would be revealed during one or both of those adjustments if that were the source of difficulty. Be sure that you also have selected on the K2 front panel the correct antenna port (Ant 1/2) to which your dummy load is attached. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/KAT2-high-SWR-problem-tp7563004p7563023.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] BL2 w/Multi-Band Dipole
Hi David, An 18 inch jumper cable won't produce a dramatic shift in feedpoint impedance over that presented by a direct connection (via a double male BNC) to the K1/K2 ATU even on 10 meters. If an adequate SWR can be obtained by the ATU (VSWR less than 2.0) with the coax jumper in place on the bands of interest (you may need to try the two different balun ratios), you can be happy. If you want to see the possible difference in the impedances presented to the ATU for any given impedance at the BL2 BNC connector, the TLW program, written by Dean, N6BV and supplied with recent editions of the ARRL Antenna Book, will calculate for you the transformed impedance at the end of an arbitrary length of feedline. It's not necessary in your practical situation, but it is interesting and educational if you've not worked much with feedlines. The only concern with the direct connection is the case when there may be repetitive movement of the 450 ohm window/ladder line; you'll want to have some separate strain relief to prevent repeated flexure of the BNC female connector. The ATU connectors on my K2 are well-secured to the case, but the connector bodies are plastic. For an indoor shack environment you should have no problem either way. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/BL2-w-Multi-Band-Dipole-tp7429655p7430371.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] BL2 w/Multi-Band Dipole
Hi David, An 18 inch jumper cable won't produce a dramatic shift in feedpoint impedance over that presented by a direct connection (via a double male BNC) to the K1/K2 ATU even on 10 meters. If an adequate SWR can be obtained by the ATU (VSWR less than 2.0) with the coax jumper in place on the bands of interest (you may need to try the two different balun ratios), you can be happy. If you want to see the possible difference in the impedances presented to the ATU for any given impedance at the BL-2 BNC connector, the TLW program, written by Dean, N6BV and supplied with recent editions of the ARRL Antenna Book, will calculate for you the transformed impedance at the end of an arbitrary length of feedline. It's not necessary in your practical situation, but it is interesting and educational if you've not worked much with feedlines. The only concern with the direct connection is the case when there may be repetitive movement of the 450 ohm window/ladder line; you'll want to have some separate strain relief to prevent repeated flexure of the BNC female connector. The ATU connectors on my K2 are well-secured to the case, but the connector bodies are plastic. For an indoor shack environment you should have no problem either way. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/BL2-w-Multi-Band-Dipole-tp7429655p7430359.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Transmitter Alignment
Which parts of the alignment do you wish to do with a scope? I found it useful only for the final alignment of the LC filters in transmit mode because I don't have a sensitive QRP-level wattmeter. I used a modest old scope (Tek 2215) with a 10X probe, a BNC tee, and a good dummy load (Bird TermaLine). The rest of the alignment can be done adequately with just a DMM and the prescribed methods of the K2 manual, but filter alignment and BFO settings can be improved upon by using Spectrogram or any other audio spectrum analysis tool - there are lots of postings on this issue in the forum archives. I ran my K2 very happily for 4 years after using only the K2 manual's procedures for alignment, then re-did them last summer with Spectrogram. I can't claim any dramatic performance improvements except that I could see where the filter passbands were actually located. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Transmitter-Alignment-tp7406224p7407085.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 cannot calibrate dial
Hi Bartek, Glad all worked out well with the re-alignment - enjoy your K2! 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-cannot-calibrate-dial-tp7366847p7370745.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 cannot calibrate dial
Hi Bartek, Presuming that you can see some response (frequency display change) when you vary C22, you might try the following procedure: 1) Re-set C22 to its mid-point setting (the default option in the Alignment and Test, Part II, p. 63 of the Rev. H manual) 2) Repeat the PLL Reference Oscillator Range Test, (also page 63) 3) Repeat the VCO Alignment (page 64) and especially note the VCO control voltage measurements, which should be within the indicated range (here I'm presuming you have access to a DMM). 4) Repeat the BFO Test (page 65) and especially verify that the BFO High and Low frequencies as well as the BFO Range are within specifications. (It was at this stage in my own K2 test and alignment that I found a problem with an intermittent connection to L33 and an insufficiently low BFO Low frequency). A measurement of the 4.0 MHz Reference Oscillator frequency with an independent, well-calibrated counter is a worthwhile step. However, if the BFO frequency range is not within the specifications, you may find this to be the source of your problem. You may find that in performing N6KR's 4.0 MHz Reference Oscillator alignment procedure, step 2, (I did this with the 10.0 MHz WWV signal) that you can't get the last 4 digits of the VCO and BFO frequencies to agree when you adjust C22, which may stem from inadequate or offset tuning ranges for either of these oscillators. Let us know what you find! 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-cannot-calibrate-dial-tp7366847p7367309.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 cannot calibrate dial
Hi Bartek, I suggest you try W3FPR's dial calibration method if you have not done so already. You can find it at Don's web page http://w3fpr.com/ under the left side menu, "Setting the K2 Dial Calibration." If you only adjust C22 and do not run CAL FCTR, CAL BFO, and CAL FIL as described by N6KR and W3FPR, you will not have reset the stored DAC values from which the actual frequency display is computed. I finally tried Don's method this past summer after using my K2 for nearly 4 years -- it made a huge difference from my initial hasty calibration in the excitement of putting the rig on the air for the first time! 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-cannot-calibrate-dial-tp7366847p7366886.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Voltage reading on K2 display low
Ed, A 2 V drop sounds excessive - the internal series protective diode in the positive 12 V supply line does reduce the voltage sensed by the K2's internal voltmeter, but not by more than 0.5V under normal conditions. Are you reading the voltage on the K2 display in TX or RX mode? What is the indicated current draw on the K2 display in each mode? 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Voltage-reading-on-K2-display-low-tp7361749p7361804.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Accessory Build order
Fred, Having gone partially through this process recently, I would vouch for Don's recommendation that you do first what most adds to your desired operating capabilities. I would add only one small caveat though - the KAT2 installation requires removal of the heat sink portion of the bottom cover if you did not install its connector on the RF board when you built the K2, whereas the other options you listed do not require the heat sink removal. As you may know from reading this forum, hasty removal of the heat sink cover will cause the PA transistor mounting hardware and shoulder washers to fall out. I installed a K160RX module along with a KAT2 module while I had the heat sink removed, but I postponed the installation of other already built options for those snow days to come. Do be sure to carefully re-seat the heat sink cover and check the PA transistors for short circuits as directed in the K2 manual after re-assembly. 73, Mike K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Accessory-Build-order-tp6987212p6988474.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 volume
Hi Ian, Do you have access to a RF signal generator, or can you build the crystal oscillator source shown in the troubleshooting section of the K2 manual? I've found the receiver signal tracing protocol described there to be helpful. The RF probe supplied with the K2 is useful if you have a good high input resistance DMM. There are several possible sources of unintended signal attenuation along the path from antenna connector to audio output, so more experiments will be required to deduce the section(s) in which problems may exist. You mentioned using an ATU with your longwire antenna -- if it's the KAT2 inside the K2, did you check to be sure that your antenna port selection in the menu is for the connector to which the antenna is actually connected? Do you notice a difference in audio signal levels on different bands or is the audio output uniformly low on all bands? 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-volume-tp6699863p6700080.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] I tried Support without a word in return -- so I'll try this
Rick, Presuming that you've already taken Don's customary advice (check all solder joints and re-heat anything that looks suspicious) in the vicinity of the 1st crystal filter, I would verify that one of the other crystals (X1 through X4) hasn't been inadvertently placed into one of the slots for X7 through X11 (the 1st variable bandwidth filter) or X5/X6 (the post-IF amp filter), and I would carefully check the varactors D29 through D34 to be sure they're the correct diodes. If these checks don't reveal anything amiss, I would repeat the BFO Test and BFO Alignment (more often referred to as CAL FIL) from the Part II Alignment and Test procedures to be sure that your BFO tuning range and BFO frequency settings for the various filters FL1 through FL4 haven't effectively put the down-converted RF signal on the skirts of the 1st crystal filter's passband. Since you have an external RF signal source, you could use Spectrogram to check the position of a known input frequency at the antenna when it's mixed down to the audio range -- if you don't see the spike in the audio spectrum inside the filter's response passband, that's a good indication of the BFO frequency being incorrectly set. All of this presumes that you have an independent means (i.e., good external counter) to check the frequency of the RF input signal and that you observe a peak in the audio response when the K2 frequency display matches the RF input frequency (CW mode, not USB or LSB). Don may have other suggestions based on his extensive knowledge of common K2 maladies. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Re-I-tried-Support-without-a-word-in-return-so-I-ll-try-this-tp6650837p6651015.html Sent from the Elecraft mailing list archive at Nabble.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] WTB: K160RX module
If anyone has a surplus K160RX module for the K2 that you're willing to sell, please contact me privately at K8CN (at) arrl (dot) net. Thanks! Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-WTB-K160RX-module-tp6631966p6631966.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 Front Panel assembly question
Hi Ron, Check Figure 5-9 on page 27 of the rev. H manual - the spacers are used only temporarily to set the height of the backlight assembly prior to soldering its pins in place. I suppose any other means you might devise to keep the backlight 1/8 inch off the front panel board and parallel to it would be acceptable (presuming you can extract the spacer after the backlight pins are soldered :) ). Don, W3FPR may have a better suggestion. 73, Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-Front-Panel-assembly-question-tp6485680p6489056.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Will the K2 noise blanker help with this QRM?
Owen, Unless I'm reading the waterfall spectrum frequency scale incorrectly, the line spacing you see on 80M is suspiciously close to 60 Hz. Do you observe this same interference line spacing across the 80M band, or only in the vicinity of 3580 kHz? The audio file sounds like the noise I experience here in the northeast U.S. during much of the year, except immediately after a strong rainstorm, which suggests an arc source on the nearby utility distribution system in my own situation -- your source(s) may be different. While there are many possible methods of 60 Hz power line interference coupling into your setup, most involve some form of common-mode coupling. A good tutorial on this issue is Jim, K9YC's article, which has been frequently cited in this forum: http://www.audiosystemsgroup.com/RFI-Ham.pdf . Another widely cited article is that by Chuck, W1HIS: http://www.yccc.org/Articles/W1HIS/CommonModeChokesW1HIS2006Apr06.pdf . Others have weighed in on the feasibility of attenuating the interference with DSP, but I would start by trying to eliminate possible sources of 60 Hz noise within your own household. Try running your K2 from a battery source while turning off individual power circuits at your breaker panel (if accessible to you), and see if the noise disappears. Of course it's essential to enlist the support of other members of the household before you begin turning off their favorite gadgets! The interference sources may well be outside your own apartment, yet within your building, in which case greater diplomatic skill is required. Your 40M noise source sounds qualitatively different to me from that on 80M, and the waterfall spectrum display is obviously different from that you observed on 80M. It would appear that you may be dealing with at least two different sources of interference. 73, and good luck! Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Will-the-K2-noise-blanker-help-with-this-QRM-tp5864463p5871947.html Sent from the [K2] mailing list archive at Nabble.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
Re: [Elecraft] Nabble down
Nabble appears to have adopted a modified form of URL for its reflector groups. The link from the Nabble main page to the Elecraft reflector is now http://elecraft.365791.n2.nabble.com/. The current link from the Elecraft page is http://n2.nabble.com/Elecraft-f365791.topics.html, which results in the Error 500 response from Nabble. Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Nabble-down-tp5461647p5461997.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] Nabble down
The link from the Elecraft reflector page appears to be broken. I went to Nabble directly and clicked on the Elecraft link there, and the reflector came up correctly. Mike, K8CN -- View this message in context: http://elecraft.365791.n2.nabble.com/Nabble-down-tp5461647p5461718.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] [OT]Grounding Antenna when not in use
Guy's story reminds me of an experience in my teenage days when I had a tri-band, 2 element cubical quad on a 40 foot tower. I had made a crude grounding rack for the separate feedlines using nails appropriately spaced in a scrap 2x4 to hang the PL-259s, and the nails were grounded to the mains ground with some wire braid stripped from old coax. I returned home from a family vacation one summer to find the PL-259s welded to the nails. There was no sign of other damage, so there must have been a relatively gentle surge induced by lightning. I don't recommend my grounding technique (I was 14 or 15 and pretty naive about lightning-induced currents), but I still disconnect feedlines (and ground them!) religiously. Mike, K8CN -- View this message in context: http://n2.nabble.com/Re-OT-Grounding-Antenna-when-not-in-use-tp4768946p4770901.html Sent from the Elecraft mailing list archive at Nabble.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
Re: [Elecraft] K2 working on 40M
I'll add hearty congratulations as well. L33 is indeed the tricky part (don't ask me how I know, but Don's advice to re-heat suspicious solder joints comes to mind) and you've done well to leap this hurdle. You'll be golden from here on! 73, Mike K8CN lstavenhagen wrote: > > > Again, I didn't seem to run into any trouble. My first kit and all I'm > expecting to have busted something but so far all OK (even the install of > L33 hi hi). Maybe I'll mess something up putting in the transmitter and > the rest of the RX in the next build phase, who knows hi. > > > -- View this message in context: http://n2.nabble.com/K2-working-on-40M-tp4554916p4559205.html Sent from the [K2] mailing list archive at Nabble.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
Re: [Elecraft] Nabble
John, I, too, suffered this apparent loss of access to Nabble2 without any changes locally. I found that I only needed to click on the Elecraft link on the upper left corner to bring out the full forum listing. 73, Mike, K8CN Durham, NH -- View this message in context: http://n2.nabble.com/Nabble-tp734023p737110.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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
Re: [Elecraft] K2: squeezing rig causing frequency change...
Steve, If memory serves me correctly, L33 (the BFO coil on the underside of the main RF board) has very little clearance to the bottom cover, and I found the same mild detuning when pressing on the bottom cover. Mike, K8CN K2/10 #5569 Steve Kallal wrote: > > I was trying to calibrate the frequency on my K2/100 and noticed that > the received beat frequency changed when attaching the top cover (the > KPA100 option). After putting the mounting screws back in, I noticed the > frequency will again change when squeezing the top and bottom covers > towards each other with my fingers. The change is about 50 to 100 Hz or > so. > > Is this normal? Somewhat I don't think so, but hadn't paid attention > before. I've been monitoring WWV on 10 MHz in CW mode beating against > the spot tone. There is constant carrier to beat against, and I that's > how I noticed the beat frequency changed. > > In the meanwhile I will tighten everything down again. > > 73, > > Steve N6VL > K2/100 #2289 > > ___ > 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 > > -- View this message in context: http://n2.nabble.com/K2%3A-squeezing-rig-causing-frequency-change...-tp527949p528002.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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
Re: [Elecraft] K2: A small milestone!
TF3KX wrote: > > > Now, do you give any insights on how this was achieved? Working contests, > odd hours, simply lots of time on the air, using announcements of > DXpeditions, clusters, studying propagation, etc.? > > 73 - Kristinn, TF3KX > > > Hi Kristinn, Although I've been a ham for 41 years, I was totally unfamiliar with QRP until late August 2007 when I completed the K2 construction and put it on the air. Thus, my observations about how this small (and I do emphasize small) achievement came about will not be great secrets revealed to those who have practiced QRP for many years. Indeed, I have local friends with more than 250 countries worked QRP, so this advice from a "newbie" is given rather self-consciously: (1) Location helps, and don't be afraid of contests. The Northeast U.S. has easy access to the many countries of EU on several bands. I had not even thought of attempting QRP DXCC until a brief entry into the CQ WW CW test last fall convinced me that I could work DX in QRP mode. I've not yet begun a thorough log analysis to see how the long doublet helped, but my recollection is that I worked more than 50 DXCC entities on the 20 meter attic dipole, and many of them in that single contest. I attribute this good fortune to location and to the skilled contesters on the other end who worked hard to dig my signal from the QRN/QRM. The ARRL DX test this spring added another 20 or so entities with just 9 hours of activity -- contests definitely are more time-efficient as a harvesting tool! (2) Study propagation. I had only been casually active on the bands before completing the K2, and my knowledge of best times/bands to reach certain parts of the world was superficial. I began listening more frequently with the K2, even if only for a few minutes, at various times during the day on several bands just to hear what might be coming in. If a station seemed loud, I would try a call. Eventually I built up a sense of just how loud a DX station needed to be so that I might have a chance to be heard there. I didn't take advantage of propagation prediction tools, but would have done so had I not been more concerned with using limited hobby time for on-air listening/making QSOs. (3) Re-arrange schedules if possible. I didn't have a lot of on-air time available to me because of work and family responsibilities, but I did shift those around as best I could to take advantage of propagation patterns that became evident over time. I didn't consider the hours odd -- I tried to be active in the early mornings for grey line propagation into the South Pacific, weekend mid-mornings to EU, mid-to late afternoons for Africa and the Middle East when I could get away early, and early evenings for whatever was still open in the Z-0300Z interval. Can't recall doing any really late night operation even during contests -- those other duties still beckoned the next morning! (4) Use DX spotting clusters off-line. I didn't use clusters in real-time, and still don't do so. However, I did find them to be a tremendous help in discerning when, and on which bands, to be on the air for particular DX regions. I looked for reporter callsigns from the Northeast U.S. to learn what they were working at various times of the day and on which bands they were finding DX entities of interest to me. If I hoped to find a regularly active DX station from a particular region, I would search for that callsign in the cluster archives and determine the most probable bands and times-of-day to listen for that station. (5) Put up more than one antenna if you have room. Both of my antennas run North/South. I could reliably work NZ/AU stations on 40 meter grey line propagation, but battled to pull out a few Caribbean stations that should have been easy pickings. I'll be adding an East/West oriented wire this summer! (6) Be persistent - QRP builds character! I say this from experience: after fighting for large portions of several weekends over the span of nearly 3 months to put up the long doublet high and in the clear above many overhanging tree branches, I learned a new patience and persistence that I didn't have previously. The same may be said of the on-air experience -- I kept calling, refined my timing of calls in pileups, and tried the trick of calling slightly off frequency from the previous station who worked the entity I was chasing. Eventually the log filled up.. 73, Mike, K8CN -- View this message in context: http://www.nabble.com/K2%3A-A-small-milestone%21-tp17416782p17521312.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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
Re: [Elecraft] K2: A small milestone!
Hi David, This was a CW-only endeavor. Once I get the KSB2 module installed, I will try my hand at digital mode QRP DXCC. Thanks, Mike, K8CN What modes? -- View this message in context: http://www.nabble.com/K2%3A-A-small-milestone%21-tp17416782p17427507.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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: A small milestone!
Although this will come as no surprise to many readers of this forum, it is possible at the very trough of the sunspot cycle to persist and even prosper in QRP mode: K2/10, #5569, was placed in service on 29 August 2007, and has always been operated at 5 W or less. QRP DXCC achieved 22 May 2008 thanks to 5B/LZ2HM. Antennas used: 20 meter attic dipole; 135 foot doublet, ladder line fed, at 50 feet. Longest path: VK3XU, near Melbourne, at approximately 10,527 miles (> 2000 miles/watt; 40 meter grey line!) I offer this as encouragement to those who occasionally lament the dearth of sunspots and opt for QRO! Cheers, and a spot of bubbly to all, Mike, K8CN Durham, NH -- View this message in context: http://www.nabble.com/K2%3A-A-small-milestone%21-tp17416782p17416782.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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] OT: K2 elation!
Had to share the elation: snagged FO/OH1RX on 80 M CW at gray line this morning -- K2 running 5 W to 135 foot doublet, window line feed, at 50 feet. Mike, K8CN K2 #5569 New Hampshire -- View this message in context: http://www.nabble.com/OT%3A-K2-elation%21-tp14998762p14998762.html Sent from the Elecraft mailing list archive at Nabble.com. ___ 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
