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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Re: QCX freq/display calibration
You need the PPS signal to calibrate the crystal frequencies. The serial data is for time and info only. The calibration takes a few seconds and you should see a new value that most probably don't end in a lot of 0's.
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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?
Get
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Re: QCX firmware 1.00e release
Thanks for the update Hans. 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
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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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
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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Hew VA7HU wrote... I got my kit last week and just getting ready to start
assembling on the weekend. I have printed the whole manual. I 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: I have built #585 and the receive section is working along with the display and the sub menu items. The rig aligned as per the manual. The keyer and side tone are working.
?
However, the transmitter is not working. CLK0 and CLK1 are displaying quadrature wave forms. But here is no CLK2 output. I isolated IC1-pin 6 and still no output. So I decided to strip out IC1 and its associated components and substitute an Adafruit 5351 breakout board (didn’t realize that QRP Labs also has a similar breakout board). I changed the 27mHz crystal from the QCX to the Adafruit board in place of the 25mHz SMD Adafruit crystal.
?
CLK0 and CLK1 are operative but still no CLK2. I disconnected pin 6 again and still no output. Since the same condition appeared in both approaches I’m suspecting IC3 may be faulty. I do have a second Adafruit board and could try the same procedure to see if an unconnected CLK2 pin would have an output.
?
Any suggestions ?
?
73, Dave NE5DL
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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.?
I found a great little inexpensive plastic enclosure that the QCX fits nicely in.? That will be the subject of a future post, however.?
Once I had the QCX CCA mounted in the enclosure, I found that the tab of the 7805 regulator was too tall and the enclosure lid would not fit.? I removed the regulator from the CCA and looked at the leads.? They are thicker near the body of the regulator, necking down into a smaller diameter about 3/16 inch away from the body.? I took an emery board and carefully filed the leads down so that they were a uniform thickness all the way along their length.? This allowed the regulator to slip into place flush with the CCA, which gave me enough headroom to close the lid on my enclosure.? Neato!? Just what I was hoping for!? So I soldered the regulator into place on the CCA...? BACKWARDS.? Yep.? I actually did this.? And I didn't notice it.? Now, I'm no noob.? This ain't my first rodeo.? I'm a Senior RF/Microwave Test Engineer with 38 years of experience at a major aerospace company and I've been a ham for over 40 years.? I was a bit distracted due to non-radio related matters.? Still, this kind of thing just doesn't happen to me.? I'm usually very, very thorough!? Well, as I said, I didn't notice the mistake.? I powered up the QCX.? The display lit up for an instant, then the 1 A fuse in my power lead failed (note to everyone -- ALWAYS use a fuse in your power lead because you never know when something unexpected will occur).? I started looking for a cause, and I almost immediately noticed the incorrectly installed regulator.? DUH!!!? I removed it again.? Unfortunately, the plated-through vias pulled out of the board.? Damn!? I looked over the board and it looked like it should still work, so I went ahead and soldered the regulator back into place, correctly this time, and powered up the QCX again.? The display lit up.? I had audio in the headset.? I hit the key, and I had full transmit power.? The VFO was right on frequency.? The CW note sounded clean in my K3's receiver.? I was overjoyed!? That is, until I realized that I didn't hear any signals coming in on the QCX.? I switched the antenna over to the K3, and the pan scope showed strong signals all across the band.? The QCX wasn't hearing any of them.? I switched K3 into my dummy load, dialed the K3's transmitter down to 0.1 Watts, and hit the key.? The QCX did not hear the K3's signal.? CRAP!? I set up the QCX to allow me to run through the alignment checks again.? It ain't hearing itself.? No 700 Hz tone.? No received signal at all.? I get good audio, and it has the characteristic sound of the 200 Hz filter.? Everything seems to be functioning correctly.? But the receiver is not hearing a bloody thing.? What the devil did I kill?? I can't believe this!? I was sooooo close to being all finished with this project, and now it's broken!?
Anyone have a suggestion as to where to look for the failure?? This one has me stumped.?
73/72,
Dean K5DH? --? very depressed!
20m QCX msn 612
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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:
If you are running is straight key mode (Menu 4.1 Keyer mode: Straight), then the QCX must just ignore the ring or "Dah" input...
Only when you enable other keyer modes does it use the ring input for dah.
74, Nick VK4PLN
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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.
73 - Hew
VA7HU
toggle quoted message
Show quoted text
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 be
printing it off soon... I didn't print any of the manuals. I just opened them up
on a tablet (iPad) and used it while working on the QCX etc.
I'm about half way through the second one, but haven't wound
the toroids for the first one yet. Procrastination? Fear?
I'll decide tomorrow.
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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)
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Re: QCX Build in a ALU case
Beautiful work, Nick!? Great job.? It looks very professional.?
73/72,
Dean K5DH
20m QCX msn 612
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Stupid! Stupid! Stupid! I killed my QCX receiver!
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.?
I found a great little inexpensive plastic enclosure that the QCX fits nicely in.? That will be the subject of a future post, however.?
Once I had the QCX CCA mounted in the enclosure, I found that the tab of the 7805 regulator was too tall and the enclosure lid would not fit.? I removed the regulator from the CCA and looked at the leads.? They are thicker near the body of the regulator, necking down into a smaller diameter about 3/16 inch away from the body.? I took an emery board and carefully filed the leads down so that they were a uniform thickness all the way along their length.? This allowed the regulator to slip into place flush with the CCA, which gave me enough headroom to close the lid on my enclosure.? Neato!? Just what I was hoping for!? So I soldered the regulator into place on the CCA...? BACKWARDS.? Yep.? I actually did this.? And I didn't notice it.? Now, I'm no noob.? This ain't my first rodeo.? I'm a Senior RF/Microwave Test Engineer with 38 years of experience at a major aerospace company and I've been a ham for over 40 years.? I was a bit distracted due to non-radio related matters.? Still, this kind of thing just doesn't happen to me.? I'm usually very, very thorough!? Well, as I said, I didn't notice the mistake.? I powered up the QCX.? The display lit up for an instant, then the 1 A fuse in my power lead failed (note to everyone -- ALWAYS use a fuse in your power lead because you never know when something unexpected will occur).? I started looking for a cause, and I almost immediately noticed the incorrectly installed regulator.? DUH!!!? I removed it again.? Unfortunately, the plated-through vias pulled out of the board.? Damn!? I looked over the board and it looked like it should still work, so I went ahead and soldered the regulator back into place, correctly this time, and powered up the QCX again.? The display lit up.? I had audio in the headset.? I hit the key, and I had full transmit power.? The VFO was right on frequency.? The CW note sounded clean in my K3's receiver.? I was overjoyed!? That is, until I realized that I didn't hear any signals coming in on the QCX.? I switched the antenna over to the K3, and the pan scope showed strong signals all across the band.? The QCX wasn't hearing any of them.? I switched K3 into my dummy load, dialed the K3's transmitter down to 0.1 Watts, and hit the key.? The QCX did not hear the K3's signal.? CRAP!? I set up the QCX to allow me to run through the alignment checks again.? It ain't hearing itself.? No 700 Hz tone.? No received signal at all.? I get good audio, and it has the characteristic sound of the 200 Hz filter.? Everything seems to be functioning correctly.? But the receiver is not hearing a bloody thing.? What the devil did I kill?? I can't believe this!? I was sooooo close to being all finished with this project, and now it's broken!?
Anyone have a suggestion as to where to look for the failure?? This one has me stumped.?
73/72,
Dean K5DH? --? very depressed!
20m QCX msn 612
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Re: QCX 80 Transceiver - Connection for a Straight Key
Actually, I am thinking this can be resolved in firmware:
If you are running is straight key mode (Menu 4.1 Keyer mode: Straight), then the QCX must just ignore the ring or "Dah" input...
Only when you enable other keyer modes does it use the ring input for dah.
74, Nick VK4PLN
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Re: QCX 80 Transceiver - Connection for a Straight Key
I added a mono jack on mine or you can use a stereo to mono adapter to use a straight key or external keyer. A mono plug inserted creates a short.
?
I recently built a 1-watter QRP kit that uses a "smart jack" - it automatically places the keyer in straight key mode when a mono plug is inserted. Something like that would be nice with the QCX.
Steve, N4IAG
?
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Re: QCX20M #585 Transmitter Inoperative
It might be interesting if someone would write a set of test programs that supported
individual function testing.? In this case the code would activate only CLK-2 on the
Si5351a and thus allow signal tracing to determine if the IC was bad, wiring was
bad, or configuration was bad, or possibly original software had a glitch and was
not activating CLK-2.?
_._
On Wed, Dec 6, 2017 at 2:42 PM, Dave Lear <de.ne5dl@...> wrote: I have built #585 and the receive section is working along with the display and the sub menu items. The rig aligned as per the manual. The keyer and side tone are working.
?
However, the transmitter is not working. CLK0 and CLK1 are displaying quadrature wave forms. But here is no CLK2 output. I isolated IC1-pin 6 and still no output. So I decided to strip out IC1 and its associated components and substitute an Adafruit 5351 breakout board (didn’t realize that QRP Labs also has a similar breakout board). I changed the 27mHz crystal from the QCX to the Adafruit board in place of the 25mHz SMD Adafruit crystal.
?
CLK0 and CLK1 are operative but still no CLK2. I disconnected pin 6 again and still no output. Since the same condition appeared in both approaches I’m suspecting IC3 may be faulty. I do have a second Adafruit board and could try the same procedure to see if an unconnected CLK2 pin would have an output.
?
Any suggestions ?
?
73, Dave NE5DL
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Re: QCX 80 Transceiver - Connection for a Straight Key
Hi Robin.
I have experienced this with other setups as well. A mono plug in a stereo socket will cause the ring and ground of the socket to short, thus keying a "dah".
Its simple to a stereo plug...
Cheers.
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QCX20M #585 Transmitter Inoperative
I have built #585 and the receive section is working along with the display and the sub menu items. The rig aligned as per the manual. The keyer and side tone are working.
?
However, the transmitter is not working. CLK0 and CLK1 are displaying quadrature wave forms. But here is no CLK2 output. I isolated IC1-pin 6 and still no output. So I decided to strip out IC1 and its associated components and substitute an Adafruit 5351 breakout board (didn’t realize that QRP Labs also has a similar breakout board). I changed the 27mHz crystal from the QCX to the Adafruit board in place of the 25mHz SMD Adafruit crystal.
?
CLK0 and CLK1 are operative but still no CLK2. I disconnected pin 6 again and still no output. Since the same condition appeared in both approaches I’m suspecting IC3 may be faulty. I do have a second Adafruit board and could try the same procedure to see if an unconnected CLK2 pin would have an output.
?
Any suggestions ?
?
73, Dave NE5DL
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Re: U3S drift/chirp - again!
Ian,
I did some measurements on my U3S with OCXO tonight. Calibrated a warm TS590S (TCXO) on air 5MHz and to my rubidium 10MHz to within 1Hz in WSJT-X. Condx bad for 30/20m beacons tonight.
Listened with the 590 (small antenna on the bench) on the 27MHz crystal and found it to be slightly off for some reason, the U3S repeatedly calibrated to 26 998 040 and the 590/wsjtx said 26 998 048 (0.3ppm). This is about the same 3Hz someone reported for the GPS ProgRock at 10MHz, IIRC it was 2Hz low ? Anyways, this might be within drift of all components here. Started some WSPR2 transmission on 6m without LPF and into a dummy load, 60sec calibration and 60s idle (park mode 3). The 27MHz frequency variation was less than 1Hz, a fast jump up some 0.5Hz when the WSPR started and peaking in the end of the transmission. Slowly going down in the calibration (almost flattened out) and then lowered some 0.1Hz more when idling and returning to 0.2Hz above the last idling frequency. Repeated cycles made the frequency return to almost the same as the previous.
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Daniel Ekman SA2KNG
Kurt Zimmerman
Nick VK4PP