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Re: Low Power fix on QCX 80 and a sugestion for a possible addition to QCX test gear to measure inductance.
When I trimmed the number of turns on the inductors (L1, L2, L3 and L4) I decided through lack of time to avoid the cut-n-try approach in favour of the measuring the inductors and adjusting turns until they matched the specified values in the manual. It was more labour intensive but I felt it had a better chance of success given my currently limited spare time.Robin, Although I do not have a QCX it looks possible just to remove one end of an inductor, unwind one turn and resolder to the top of the board. The unwound length will have only a very small inductance. Then test, remove another turn, or even rewind that turn. That is the way I have adjusted inductors on similar boards. L1 manual says 25 turns (had to remove 5 turns)Of course if you have an inductance meter you can trust then use that. Obviously if you remove more turns than you need then it will appear to work but harmonic rejection may not be so great. 73 Alan G4ZFQ |
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QCX WSPR
What a fun kit to build. Every thing follows your instructions to a T.
I have it transmitting on 20m cw with a recorded CQ. What I don under stand is wspr. I have all the info set, but what do I do to actually get the WSPR to start? I read that part of the instructions so many times, that I probably just missed it' so I need someone to slap me in the forehead. Thanks Terry? W6LEO |
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Re: progrock on power up
Hi Alan, I've taken your suggestion and done the factory reset but still the same issue. On power up, does the LED come on first then flash four times? Perhaps I'm just missing a flash. Hopefully the issue is with my eyes and not the unit - it does flash quickly. I'll plug it into the receiver in the next few days and see what happens. Thanks, Chris.
On Thursday, December 7, 2017, 11:59:38 AM NST, Alan G4ZFQ <alan4alan@...> wrote:
> The user manual states that on power up the LED should blink 4 times and > go out. Mine blinks like a CW 'D' (one long pulse followed by two short) > and then remains off. Does this indicate a problem? > Chris, If it really is a D then I've not seen it. Try a reset as in section 4.2 All I see is rapid flashes, so fast I'm never sure I've seen 4. But then I'm probably just slow.. The FOX will be close to 27000000 73 Alan G4ZFQ > As recommended in the instructions, I've grounded the 1pps pin. The > voltage regulator (5.2V) and the noise filter (3.7V) voltages are within > Han's 5% tolerance. My thought is that the timing between the first and > second pulse is too short to perceive and they are blending into one > long pulse. The LED turning off should indicate the I2C connection is > established? I'm using the FOX924B TCXO on the Synth and am new to SMD > soldering (can't figure out a way of double checking the connections, > but the solder is very shinny). > > Also, can anyone recommend a ballpark reference frequency for the FOX TCXO? |
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Re: Low Power fix on QCX 80 and a sugestion for a possible addition to QCX test gear to measure inductance.
Hi Robin,
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Sadly I dont think I can help on this one. When I trimmed the number of turns on the inductors (L1, L2, L3 and L4) I decided through lack of time to avoid the cut-n-try approach in favour of the measuring the inductors and adjusting turns until they matched the specified values in the manual. It was more labour intensive but I felt it had a better chance of success given my currently limited spare time. I performed the measure, adjust and re-measure on each inductor and then re-fitted all the inductors into the board in one operation so I did not notice which (if any) of the inductors made the biggest change to the power output. What I can say is that my inductors started off with the specified number of turns but ended up being way-off due (I suspect) to the well documented and notoriously poor sample-to-sample tollerances of this type of core. If it helps I can tell you how many turns I had to remove from each core... L1 manual says 25 turns (had to remove 5 turns) L2 manual says 27 turns (had to remove 4 turns) L3 manual syas 25 turns (had to remove 5 turns same as L1) L4 manual says 24 turns (had to remove 5 turns) As an aside, I rummaged around the shack and found some old (very old, 20 years +) T37-2 cores and wound the specified number of turns as a check to satisfy curiosity as to the s-p-r-e-a-d in core characteristics with cores from different suppliers and of different ages. The result was that in almost all cases the final number of turns required for a given inductance is subject to "tweaking" due to tollerances in the core. Conclusion: they have not got any better over the years Hi. Hope you enjoy the QCX and look forward to hearing you on-air. 73,s Des (M0AYF) On Wed, Dec 6, 2017 at 08:52 am, <robin.travis@...> wrote:
Des and Alan |
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Re: progrock on power up
The user manual states that on power up the LED should blink 4 times and go out. Mine blinks like a CW 'D' (one long pulse followed by two short) and then remains off. Does this indicate a problem?Chris, If it really is a D then I've not seen it. Try a reset as in section 4.2 All I see is rapid flashes, so fast I'm never sure I've seen 4. But then I'm probably just slow.. The FOX will be close to 27000000 73 Alan G4ZFQ As recommended in the instructions, I've grounded the 1pps pin. The voltage regulator (5.2V) and the noise filter (3.7V) voltages are within Han's 5% tolerance. My thought is that the timing between the first and second pulse is too short to perceive and they are blending into one long pulse. The LED turning off should indicate the I2C connection is established? I'm using the FOX924B TCXO on the Synth and am new to SMD soldering (can't figure out a way of double checking the connections, but the solder is very shinny). |
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Re: Winding Tip for 80 Mtr QCX transformer (T1)
Hi Robin & the group,
I see a number of people have allready responded with some good advice on this one but heres my 10p (10c) worth. I would go along with the idea that adding a small capacitor in parallel with the trimmer is the simplest option and saves the "stress" of changing the number of turns on T1 and the only issue I can see with that is that by adding a capacior accross the trimmer you slightly reduce the total "swing" or range of tuning possible for T1. So at some future date you may want to peak in a different part of the band and not be able to do so due to the reduced tunning range. In practical terms it may not matter very much as the receiver is very sensitive and even signals off-tune are still of easily copied. My QCX is "peaked" at 3.560 MHz but still works perfectly well over the rest of the CW range. I "peaked" around 3.560 MHz to make it most sensitive in the area where one might expect to hear other (possibly weak) QRP signals. Regarding "tweaking" T1 turns. I wound my T1 with too many turns on purpose with the notion that it would be easier to take turns off as oposed to adding them. I soldered all but one terminal of secondary 3 into the board permanently. The end of the secondary 3 winding (tuned winding) was soldered in "lightly" so it could be removed without to much difficulty. I had to remove quite a few turns on my T1 but with the aid of a pair of tweezers a few turns at a time can be removed with patience and the end of the tuned winding re-soldered. I seem to remember it took me 3 or 4 re-workings before I got my trimmer roughly mid-position. 73,s Des (M0AYF) |
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progrock on power up
Hi All, I just completed assembling a progrock that I'll use in a QRP receiver. The user manual states that on power up the LED should blink 4 times and go out. Mine blinks like a CW 'D' (one long pulse followed by two short) and then remains off. Does this indicate a problem? As recommended in the instructions, I've grounded the 1pps pin. The voltage regulator (5.2V) and the noise filter (3.7V) voltages are within Han's 5% tolerance. My thought is that the timing between the first and second pulse is too short to perceive and they are blending into one long pulse. The LED turning off should indicate the I2C connection is established? I'm using the FOX924B TCXO on the Synth and am new to SMD soldering (can't figure out a way of double checking the connections, but the solder is very shinny). Also, can anyone recommend a ballpark reference frequency for the FOX TCXO? Best, Chris, VO1CKD. |
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QCX freq/display calibration
Greetings all; ? So I put my QCX-20 on the air last night to check calibration. I am using my Yaesu FT-920 as my frequency standard. I noticed both TX/RX freq are a few kHz. I don’t recall anything written about calibration other than using the GPS RX to calibrate the XTAL.? Has anyone else had a calibration issue? I haven’t seen any discussion about this unless I missed something. 72; Kurt-W2MW?
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Re: QCX firmware 1.00e release
Thanks for the update Hans.
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73 Tim KB2MFS<div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br /> <table style="border-top: 1px solid #D3D4DE;"> <tr> <td style="width: 55px; padding-top: 13px;"><a href=" target="_blank"><img src=" alt="" width="46" height="29" style="width: 46px; height: 29px;" /></a></td> <td style="width: 470px; padding-top: 12px; color: #41424e; font-size: 13px; font-family: Arial, Helvetica, sans-serif; line-height: 18px;">Virus-free. <a href=" target="_blank" style="color: #4453ea;">www.avast.com</a> </td> </tr> </table><a href="#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2" width="1" height="1"></a></div> On Thu, Dec 7, 2017 at 3:49 AM, Hans Summers <hans.summers@...> wrote:
Hi all |
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QCX firmware 1.00e release
Hi all QCX firmware version 1.00e is released. You don't need to upgrade unless you particularly want/need one of these changes. Changes in this version: - Bug fix: stored message sending now sends at current keyer speed (not stored default) - Bug fix: WSPR tones in the second half of the transmission were potentially corrupted As usual, you can download the .hex file from /g/QRPLabs/files/Firmware%20for%20QCX%20kit/1.00e or purchase a programmed chip in the shop if you wish All orders sent out from now onwards (and some of those sent out recently), are using this 1.00e chip. 73 Hans G0UPL |
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Re: QCX Manual
Hew VA7HU wrote...
I got my kit last week and just getting ready to startI still haven't wound any of the toroids yet, but I have the 80M version otherwise done and and I'm about 3/4 of the way through the 40M version. Which band did you go for? As I mentioned, I've just been viewing the manuals on an iPad. I can zoom and you can put post-it notes on pages you quickly want to get to! -- 73 Keith VE7GDH |
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Re: QCX20M #585 Transmitter Inoperative
Hi Dave Have you checked for a short from IC3C pins 4, 10 to Ground?? I agree, testing Clk2 when it is unconnected would be a good idea.? 73 Hans G0UPL On Thu, Dec 7, 2017 at 12:42 AM, Dave Lear <de.ne5dl@...> wrote:
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Re: Stupid! Stupid! Stupid! I killed my QCX receiver!
Hi Dean It sounds to me that you probably fried IC4, the FST3253, which is the mixer (Quadrature Sampling Detector, a.k.a. Tayloe Detector). If that is blown, the op-amps would be just amplifying noise, then filtering it with the 200Hz filter... it could explain the lack of signals. You could use the onboard DVM to take a DC voltage reading at pins 2, 3, 5 and 6 of IC5, these should be around 2.5V (approximately midrail) - if they are not, then again it points to a fried FST3253.? You say TX is working, and that implies the Si5351A is Ok. But TX only tests Clk2 of the Si5351A. So you should check Clk0 and Clk1. You can easily do this using the onboard test equipment of the QCX itself. Use "9.6 Signal gen." and set the signal generator to, say, 4MHz. Then go to "9.5 Frequency" which is the frequency counter. You should be able to hold a wire from the "Freq" test input pin, to Clk0 and Clk1 and measure 4MHz, shown on the display. Then you will know that the Si5351A is Ok.? All the op-amps run with the full supply voltage anyway, not 5V. The only components running on 5V are the LCD, IC2 (Processor), IC1 (Si5351A) via two series diodes, IC4 (FST3253) and IC3 (74ACT00).? If you find out that the FST3253 is the fried item, it should be possible to replace it with a new one. They are easily sourced. I could send you one (free of charge) but that would take time to reach you... up to you! Good luck... 73 Hans G0UPL On Thu, Dec 7, 2017 at 4:09 AM, K5DH <k5dh@...> wrote: OK, folks.? This is going to be the most stupid thing you've heard all day.? Maybe all week.? Or maybe in your lifetime.? Bear with me.? I have some 'splaining to do.? This will be a long read.? And I need some advice.? |
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Re: QCX 80 Transceiver - Connection for a Straight Key
Hi? Yes, I can add that to the next firmware version - to only key in straight mode using the tip connection; then if a mono plug shorts the ring to ground, it would not cause a problem. I can add this as a configuration so it can be enabled/disabled.? It appears Robin, you are also saying a stereo plug doesn't work? This should not be the case - the connectors are for 3.5mm stereo plugs! 73 Hans G0UPL ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? On Thu, Dec 7, 2017 at 2:04 AM, <nickpullen@...> wrote: Actually, I am thinking this can be resolved in firmware: |
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Re: QCX Manual
Lets us know how the toroids go Keith. I got my kit last week? and just getting ready to start assembling on the weekend. I have printed the whole manual.
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73 - Hew VA7HU On 2017-12-06 10:44 AM, Keith VE7GDH wrote:
Vernon VE1VDM wrote...My kit should be here in a day or two so will beI didn't print any of the manuals. I just opened them up |
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Re: Stupid! Stupid! Stupid! I killed my QCX receiver!
Hello Dean,
If you think thats stupid. Try checking the frequency of CLK0 with the 12 volt pin on the three pin header. Instead of the freq. pin next to the clock. I would start with the mixer. And work your way down the signal chain towards the unity amp. -Tomasz (N6SRN) |
Daniel Ekman SA2KNG
Kurt Zimmerman
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