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Re: Has anyone ever connected QLG1 to an Arduino Uno?
Exactly. You can always define another instance of the Serial object. FWIW, I would leave pins 2 and 3 open on the Uno/Nano, as those are the only external hardware interrupt pins and I usually avoid using them as you never know when you may want to add an external interrupt. Jack, W8TEE
On Monday, April 15, 2019, 4:08:46 AM EDT, Christen Fihl <Christen@...> wrote:
Sounds easy as you only need to send data into the ?rx pin and send it to console at each newline.? Maybe do use a SoftwareSerial on another pin if rx port gets blocked by the usb console connection -- 73 Christen Fihl, OZ1AAB |
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I just assembled an OCXO and have had it running for a few days with the U3S at 18 and 14 MHz. The U3S is in the QRPLabs enclosure. It turns out that I need to have the lid off in order to reduce drift to 0. Otherwise I will get drift in the -1,-2,-3 range. This seems to indicate a heating problem, could it be that it gets too hot with the lid on? And how should I interpret the drift? Does it mean that the 27 MHz reference is drifting down in frequency during the transmission with about 27/14 times the reported drift? Could it be that I haven't found the proper sweet spot for the setting of the OCXO? -- ? LA3ZA, http://la3za.blogspot.com |
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Re: Kit shipping
Dear Hans, ??? Could you consider sending packages via a courier like DHL or TNT? It is true that there would be higher costs for buyers, but parcels would be fast and very important without loss. I have asked ?here in Romania at ?TNT, DHL and many others and ?without a continuity contract any package to be picked up from Turkey cost at least 80Euro without VAT. Assuming that they are called locally from Turkey and not through intermediaries as is my case the?costs would probably be below 40- 50Euro excluding VAT. |
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Re: QCX-20 power output
Richard Harris
Hi Chris, Several QCX 20m version builders, myself included,? found that the output filter capacitors C25 and C26 (390pF NPO ceramic) were quite lossy.? This may be due to a bad batch of capacitors from the manufacturer.? I found that holding the key down for a few seconds caused the output power to slowly rise and C25 and C26 to warm up - I checked this using an infra-red thermometer.? ? I cut out C25 and C26 and soldered 330pF + 56pF NPO ceramic to be back of the PCB (I don't have any 390pF NPO in my new components box) and the power went up to about 3W using a 13,8V PSU.? It also remained constant when the key was held down for a few seconds.?? I believe that this problem has only been reported on the 20m version of the QCX.. Richard G3OTK
On Monday, 15 April 2019, 05:11:09 BST, Chris Hobbs <chris@...> wrote:
[I know there is a recent thread on this topic, but I think I'm experiencing something different]
Hi All! I'm new to the QCX and finished building my -20 a couple of weeks ago. Other than a bad solder joint on the LED backlight everything seemed to be working well and I was able to go through the calibration steps. Now that I've got an antenna up I'm ready to start actually playing with it, and I've discovered that I'm not getting anywhere close to the power I should be for my input voltage (13.7VDC from an Astron power supply). I'm only seeing 1.0W on my MFJ-971 tuner into a 50-ohm dummy load. I've gone through the troubleshooting in section 6.5 of the manual. The pin at L1 is showing 0.74W on the internal watt-meter. The drains of all three BS170s however show 5.2W. I know the manual says this is an even less reliable measurement, but that's almost an order of magnitude difference. The manual suggests that if you have power at the mosfets but not at L1 then the LPF is to blame. It doesn't cover what the issue might be if there is RF at L1 but it's really low. I've read that removing turns from L1-3 can help, but I have a hunch the problem I've got is something more significant than what that solution might provide. Any thoughts on what I should be looking at first? Thanks in advance! Chris W6VE Chris Hobbs |
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Re: Stock QCX-17 musters only 20 milliwatts output on 28001.7 kHz
¿ªÔÆÌåÓýWell that proves that the LOW pass filter is doing its job then!! On 15/04/2019 02:56, n4qa
at_hotmail.com wrote:
Hi Allison. |
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Re: Has anyone ever connected QLG1 to an Arduino Uno?
ulidf5sf2002
Hello Kevin,
what is exact your problem ? Maybe we have the same problem. I have here Arduino UNO and Arduino Mega. With UNO I cannot receive the NMEA strings correct, with Mega it works fine. -- 73 Uli DF5SF Pirmasens, JN39te --- Diese E-Mail wurde von Avast Antivirus-Software auf Viren gepr¨¹ft. |
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Re: U3S - xmit frequency is 200 Hz higher than indicated on display
Hi John See What are you using for the parameter "Cal {Time Step}"? 73 Hans G0UPL? ? On Mon, Apr 15, 2019, 00:10 John Canfield <bucket@...> wrote: Thank you Krause, your English is better than some with English as a first language ;-) I have set the U3S up to do a calibration every few minutes, the oscillator must be stable because there is usually no change required ( = ). |
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QCX-20 power output
Chris Hobbs
[I know there is a recent thread on this topic, but I think I'm experiencing something different] Hi All! I'm new to the QCX and finished building my -20 a couple of weeks ago. Other than a bad solder joint on the LED backlight everything seemed to be working well and I was able to go through the calibration steps. Now that I've got an antenna up I'm ready to start actually playing with it, and I've discovered that I'm not getting anywhere close to the power I should be for my input voltage (13.7VDC from an Astron power supply). I'm only seeing 1.0W on my MFJ-971 tuner into a 50-ohm dummy load. I've gone through the troubleshooting in section 6.5 of the manual. The pin at L1 is showing 0.74W on the internal watt-meter. The drains of all three BS170s however show 5.2W. I know the manual says this is an even less reliable measurement, but that's almost an order of magnitude difference. The manual suggests that if you have power at the mosfets but not at L1 then the LPF is to blame. It doesn't cover what the issue might be if there is RF at L1 but it's really low. I've read that removing turns from L1-3 can help, but I have a hunch the problem I've got is something more significant than what that solution might provide. Any thoughts on what I should be looking at first? Thanks in advance! Chris W6VE Chris Hobbs |
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Re: Stock QCX-17 musters only 20 milliwatts output on 28001.7 kHz
n4qa at_hotmail.com
Hi Allison.
As per my initial post on this topic, I will answer yes *and* yes to your first sentence above - Both the stock internal lpf and an external filter for 28 MHz are deployed. A single yes to sentences two & three above. However, as to your sentence four above, I note that the datasheet for the 74ACT00N indicates that it possesses adequate drive current capability for Q1,Q2,Q3, with a maximum switching speed in the single digit ns range. This is not to say that it was ever expected that the QCX-series should operate flawlessly in the near-low-vhf range of frequencies ie 10m band, for example. I'm only saying that, with a little touch here and there, it is certainly possible to obtain *some* success there. Tnx & 72 / 73, Bill, N4QA |
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Re: Stock QCX-17 musters only 20 milliwatts output on 28001.7 kHz
Is that with a 17M low pass at the output or something else?
If the stock 17M filter is in place then its working so your loosing a lot? power to it likely 10-20db. FYI the output low pass filter has to meet conditions for a? class E.? Also you need about? 8X or more drive compared to 40M and likely the 74HC is not doing it. Allison |
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Stock QCX-17 musters only 20 milliwatts output on 28001.7 kHz
n4qa at_hotmail.com
Stock QCX-17 musters only 20 milliwatts output on 28001.7 kHz. Now, admittedly, that's not a whole bunch of output power...and it is only about 38 dB higher than the nearest 'noise', according to the cheap Meili Instruments SM-5010 spectrum analyzer, and that's not too surprising either, given the stock lpf of the QCX-17, followed by an Industrial Communications Engineers Ltd model 411 bpf.
What to do next... 72 / 73, Bill, N4QA |
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Re: U3S - xmit frequency is 200 Hz higher than indicated on display
John Canfield
Thank you Krause, your English is better than some with English as a first language ;-) I have set the U3S up to do a calibration every few minutes, the oscillator must be stable because there is usually no change required ( = ).
-- John, WB5THT |
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Re: On 24891.7 kHz, the FT-450D is receiving a sweet note from the transmitter of the stock QCX-17
Bill, Is this the one you've been "abusing"??? Are all your finals still intact? I'm actually wondering what I should do with the LPF for the QCX-20 that is on order... regards, Dave N3AC On Sun, Apr 14, 2019 at 4:53 PM n4qa <n4qa@...> wrote: In his QCX manual, sections 7.6 & 7.7, Hans includes some very interesting info about transmitter & receiver sections' filtering, mostly featuring the xmtr lpf and the rcvr bpf circuits. |
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On 24891.7 kHz, the FT-450D is receiving a sweet note from the transmitter of the stock QCX-17
n4qa at_hotmail.com
In his QCX manual, sections 7.6 & 7.7, Hans includes some very interesting info about transmitter & receiver sections' filtering, mostly featuring the xmtr lpf and the rcvr bpf circuits.
Currently, using the stock QCX-17, the WM-2 reports something on the order of 300 williwatts into the Bird 10A-MFB-30 attenuator/dummy load. So, now, I'm wondering aloud: "Do I wait for the QSX to arrive or do I dive into QCX's lpf and T1 etc whilst waiting?" 72 / 73, Bill, N4QA |
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Christen Fihl
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