[Elecraft] FW: FW: [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) U6 MEASUREMENTS
Don: Thought that I might be using the wrong address so I figured that I would try this one. Please see blow for my last measurements. Thanks. Chris. -Original Message- From: Chris Amyes [mailto:amye...@earthlink.net] Sent: Thursday, November 05, 2009 7:45 PM Subject: RE: FW: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) U6 MEASUREMENTS Don: Before removing the CB I checked U6-30 and got 4.92V. I then removed the CB and checked the following: RP4 Pins 56: Soldering ok. Resistance 81.7K U6-30 RP-6/5: Resistance is 90.6k (NOT close to ZERO) U5 TOP RP4/6: 0.000 NOTE: R1 on RFB Lifted BTU, 73 Chris -Original Message- From: Don Wilhelm [mailto:d...@w3fpr.com] Sent: Thursday, November 05, 2009 4:03 PM To: Chris Amyes Subject: Re: FW: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) U6 MEASUREMENTS Chris, You are actually looking for U6-30 (the DOT-PTT signal line) to go to about 5 volts. Do check Control Board RP4 pins 5 and 6 for good soldering - while you are at it, check the resistance *between* pins 5 and 6 (should be 82k) . Then check the resistance between U6 pin 30 and RP6 pin 5 (should be very close to zero) and between the topmost lead of U5 and RP4 pin 6 - that too should be close to zero. If those resistance readings are as they should be, put the control board back in and check the voltage at U6 pin 30 again - it should be close to 5 volts (pin 29 should also be close to 5 volts). When you have that condition (U6-30 and U6-29 = 5 volts) correct, put things back like they were and see what happens, it should be OK. 73, Don W3FPR Chris Amyes wrote: Don: Here is the result of the first part of your last email. Any suggestions? Thanks. Chris. -Original Message- From: Chris Amyes [mailto:amye...@earthlink.net] Sent: Wednesday, November 04, 2009 5:41 PM To: 'd...@w3fpr.com' Subject: RE: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) U6 MEASUREMENTS OK.After removing KSB2, the voltage at U6/30 was .161. I lifted one side of R1. U6/30 measured 0, there was no tone and the VFO was unlocked (I could change the frequency). Chris. -Original Message- From: Don Wilhelm [mailto:d...@w3fpr.com] Sent: Wednesday, November 04, 2009 5:06 PM To: Chris Amyes Subject: Re: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) U6 MEASUREMENTS Chris, The voltage on U6-30 is suspicious. Remove the KSB2 first (no jumpers necessary for this test, but the K2 will noether receive or transmit) and see if it goes to about 5 volts. If that does not cure it, next lift one end of R1 on the RF Board (remove the left side panel to access it). If that still persists, take a careful look at the mic jack and the microphone configuration header (whichever mic jack pin the configuration header wires to the PTT line). Also check the connectors between the Front Panel board pin 4 and its mating header on the RF Board as well as RF Board J8 pin 18 and its connecting pin on the Control Board. Somewhere in that path, you should find the answer to why the DOT/PTT input to U6-30 is sitting at 1.244 volts. Also be certain that Control Board RP4 pins 5 and 6 are well soldered. After all those checks 'pass muster' and the U6 pin 30 voltage is still low, then you may suspect that your firmware chip has a bad input at pin 30. BTW - ignore my private email suggestion for doing a Master Reset - it will not help if U6-30 is at 1.244 volts. 73, Don W3FPR Chris Amyes wrote: Don: The U6 Measurements are as follows: U6-27: 4.65 U6-28: 0 U6-29: 4.92 U6-30: 1.244 Chris -Original Message- From: Don Wilhelm [mailto:w3...@embarqmail.com] Sent: Wednesday, November 04, 2009 9:17 AM To: CJA Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA) Chris, The email may have arrived while I was on vacation a week ago - yes, I missed it.. Are you certain you measured the gate of Q3 and Q4? Those voltages are normal at the drains of Q3 and Q4 for a K2 in transmit. You can check U6 pin 27 (5 volts during transmit, 0 during receive) and pin 28 (5 volts during receive and 0 during transmit). If my guess is correct and you actually measured the drains of Q3 and Q4, then you do have a problem with Q2 or its associated resistors in RP1. You should not have 7 volts on *both* Q1 and Q2 collectors (if you measured the emitters instead, you will find 7 to 8 volts on both. Put that aside for a moment (that information will not solve your primary problem). Does the tone sound anything like sidetone? What I am getting to is that - from all information I have right now, that K2 is going into transmit right after a power on. That will make the buttons inactive, and you first need to find out what is causing it to transmit after turning it on. Once that is solved, you can go on to other things. Keep a dummy load
Re: [Elecraft] [K2] K2 - CONTROL PANNEL FREEZE UP (K7CJA)
Don: I sent the txt below a while back but it must have gotten lost in cyberspace. In addition to the measurements below, when I turn on the K2 now I get the full Elecraft in the LCD, a few clicks from relays and the speaker as well as a steady medium frequency tone. Nothing works on the pannel. BEGIN EMAIL I disconnected everything and put it aside for a while. Now I am back to it. The measurements are as follows: Q1 Collector: 6.77 (Fluctuates, The first time I measured it was 7.6) Q2 Collector: 7.3 (Fluctuates) Q3 Gate: .003 Q4 Gate: 7.25 Shorted Q3? How would it have shorted. I do not see anything that would have caused the short. In addition, once this issue is sorted out, I would like to go through a complete tune up procedure. I have the following upgrades in the K2 along with the KAT/KPA 100 in a separate enclosure: K60XV (No longer shows up on the LCD), KIO2, K160RX, KNB2, KAT2, KSB2, KBT2 Is there a stem to stern check-up procedure that I can follow? As always, thanks for your assistance. Chris Amyes K7CJA Don Wilhelm-4 wrote: Chris, Keep that dummy load attached, and set the power knob to zero. That K2 is going into transmit, so you want to protect the PA from harm while figuring out what is going on. Remove anything that may be plugged into either the paddle jack or the mic jack and try again. If it still goes into transmit, remove the top cover and on the Control Board, check the collector of Q1 - it will be between 7.5 and 8 volts if the K2 is in transmit. Also, check the collector of Q2, which should be at 7.5 to 8 volts during receive, If both Q1 and Q2 have voltage on the collector, it is trying to transmit and receive at the same time, so keep the power on intervals short if that condition is present. Assuming you have the 8 volts at the collector of Q1 but near zero at the collector of Q2 (proper for transmit state), then check pins 29 and 30 of Control Board U6 (the microprocessor) - both should be higher than 4 volts (close to 5 volts). If one or both are at a low voltage, there is something holding the dot or dash lines low, and you should be able to locate it with an ohmmeter and visual inspection for solder bridges or stray wire clippings. If you have both transmit and receive 8 volt lines (collectors of CB Q1 and Q2), then check the gates of CB Q3 and Q4. For receive, the gate of Q4 should be high (4.5 to 5 volts), and the gate of Q3 should be near zero. If these last conditions are true, the microprocessor outputs for transmit and receive are correct and the most likely failure is a shorted Q3. Let us know the results of those tests. 73, Don W3FPR CJA wrote: I have a K2 with a KPA100 and KAT100 in a separate enclosure. It had been working on my lossey loop but I decided to try a ground mounted Hi-Q 4/160. After connecting the antenna, I began trying to tune to the various bands. It seemed to be tuning to a low SWR when the control panel just froze up. The VFO would not change the freq and none of the buttons functioned. I turned it off and on several times and came up with the full elecraft in the LCD and then the last freq I was on. The control panel was still frozen. I then tried to reset. That did not work. Now it just goes through the POST (full elecraft in the LCD) and seems to go into transmit (dummy load connected) with a high pitched tone and hangs there. Any suggestions would be greatly appreciated. 73, Chris Amyes, K7CJA No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.409 / Virus Database: 270.14.1/2407 - Release Date: 10/01/09 06:34:00 __ 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 -- View this message in context: http://n2.nabble.com/K2-CONTROL-PANNEL-FREEZE-UP-K7CJA-tp3749758p3945996.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
[Elecraft] K2 - CONTROL PANNEL FREEZE UP (K7CJA)
I have a K2 with a KPA100 and KAT100 in a separate enclosure. It had been working on my lossey loop but I decided to try a ground mounted Hi-Q 4/160. After connecting the antenna, I began trying to tune to the various bands. It seemed to be tuning to a low SWR when the control panel just froze up. The VFO would not change the freq and none of the buttons functioned. I turned it off and on several times and came up with the full elecraft in the LCD and then the last freq I was on. The control panel was still frozen. I then tried to reset. That did not work. Now it just goes through the POST (full elecraft in the LCD) and seems to go into transmit (dummy load connected) with a high pitched tone and hangs there. Any suggestions would be greatly appreciated. 73, Chris Amyes, K7CJA -- View this message in context: http://n2.nabble.com/K2-CONTROL-PANNEL-FREEZE-UP-K7CJA-tp3749758p3749758.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 - KAT100 Resistance Checks Anomoly
I recently completed the resistance checks for the KAT100 and came up with the following seemingly minor anomalies: U2 Pin 12 to Ground: Target: 100K Measured: .1 Ohms U5 Pin 3 to ground: Target: 45-55k Measured: 56.0k Are these problem areas or do I need to trouble shoot? If these measurements are problematic, I would greatly appreciate guidance on where to start looking. Thanks and 73, Chris K7CJA K2#6442 -- View this message in context: http://n2.nabble.com/K2---KAT100-Resistance-Checks-Anomoly-tp584847p584847.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
