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Make mine a doublet
"Philip"
Been having fun messing with antennas with the help of Tony G0BZB.
We have both been trying out different setups and comparing notes using our results on WSPR. I have a 132' Windom fed to where my desk is but I wanted a seperate antenna for my garden shed where my second U2 rig is housed.. Anyhoo, threw up an inverted V doublet yesterday and it's given the best results so far on 20 meters WSPR. Bit too low but it's doing the job and it tunes nicely on 40 through 10 using a homebrew Z match ATU.. Running just over 400mW, my U2 had a great 24 hours on 20 meters WSPR. Screen grab of WSPR map and a sketch of the antenna in this album Put this antenna up in the rain as well.. That's either dedication or madness but it's great fun :) Philip G4JVF |
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Re: Ultimate 2 QRSS no work
Hans Summers
Paul, Don and co Note that a heatsink doesn't prevent drift. It just slows it down...? To get the U2 on frequency requires adjustment of the configuration setting for the 125MHz oscillator, and to get it keeping accurate time requires adjustment of the configuration setting for the 20MHz system clock crystal. In both cases you'll still have temperature related drift. But it is reasonably small. To get rid of that, you need an oven!
Now yet another future enhancement, which would require a fair amount of cleverness from me, would be to use the microprocessors temperature sensor (yes it does have one internally!) to measure the temperature and apply an automatic correction to the system clock and 125MHz reference clock settings. Now how nice would THAT be ;-)
73 Hans G0UPL On Wed, Jul 31, 2013 at 6:54 PM, Don <don1mh@...> wrote:
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Re: U2 with V2.03 firmware working FB
Hans Summers
John, Andy The crystal is from Rapid Electronics in Colchester, UK. It's this one:??. There is a datasheet there linked from that page, which takes you to??- but it isn't so kind as to show a frequency vs temperature curve or such useful information. So it might be necessary to do some measurements to determine it.
73 Hans G0UPL On Wed, Jul 31, 2013 at 5:36 PM, John Randall <m0els@...> wrote:
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Re: TX Problem
Hans Summers
Hi Andy Yes, it does appear from all reports that v2.03 is perfect. ALMOST perfect. A very few wishes include shifting that residual 25-30dB down on-frequency signal between frames. I'll get to it... v2.04 will come some time soon
73 Hans G0UPL On Wed, Jul 31, 2013 at 6:00 PM, andyfoad@... <andyfoad@...> wrote:
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Re: Ultimate 2 QRSS no work
John Randall
Hi Don, Four of the main causes for drift are heat, power supply voltage change and crystal aging. 1) Heat generated by chips can play havoc on crystals and cause them to drift up or down more so than they would naturally. 2) Unstable supply voltages also vary the voltage on the crystal causing it to drift. 3) Low quality crystals or ones with a high PPM number, will allow the crystals to? drift more than one's with a low PPM number 4) Component quality In digi modes, some modes require a high stability because of the data rate being generated. Ofcourse circuit designers should take this all into account and use high quality components in critical areas. The higher one goes in frequency ie micrwaves, the more critical it becomes. All facinating stuff. 73 John ? Digitally signed mail - M0ELS From: Don To: QRPLabs@... Sent: Wednesday, 31 July 2013, 18:54 Subject: [QRPLabs] Re: Ultimate 2 QRSS no work
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Paul and others,
You know, I think a newbie like me can easily take points out of context. I do remember seeing somewhere, probably not here, WSPR is the one mode a GPS module is "very important". But, now I see a bit differently. Off frequency can be dealt with by nudging crystals. And drift can be stopped just by a tiny heat sink on the DDS chip, which I've done. I'm expecting a module in next day, so I'll see what it does for me. Actually, I've tried WSPR a year ago with a Softrock RX/TX running about a watt, and trying to recall what all I did! Don --- In QRPLabs@..., "Paul KE7HR" > > I am on holiday up in the state of Washington and my WSPR beacon is running on 80 meters with 1 watt to a dipole up in the trees. I have been copied over 100 times overnight. I really don't think that GPS will help get more spots... The only thing it will do for you is try and keep the clocks in line and automatically set the grid square. > > The clocks can be zeroed in on with spreadsheets that are in the files section of the group. My "final" clock setting is 19,978,582 > but yours WILL be different. My DDS clock is set to 125,001,739 > but, again, yours WILL be different. Use the spreadsheets and do a few days into a dummy load to get things right before going on the air. Listen to WWV to set your clock, let it run for a day or so and note the offset. It only took me three days or so to zero in. > > Have fun and explore the group site. > > Paul (on the Olympic Peninsula) KE7HR > > --- In QRPLabs@..., "Don" wrote: > > > > Paul "The GPS is not needed" > > > > Good to know about WSPR can work without GPS. What's a good number to start with to nudge the 20 MHz oscillator? Anyway a new GPS should arrive in a couple of days, but I'll try your idea first. > > > > I ordered 2 of the Mini-Red-Step-Down PS's you mentioned. Great find! > > I managed to ordered them from a NY outfit, Noo Elec through Amazon, instead of from China. I'm sure NY gets them from China! > > > > 73...Don...W6RWN > > > > > > > > > > --- In QRPLabs@..., "Paul KE7HR" wrote: > > > > > > The GPS is not needed to make WSPR work. All of my U2 WSPR work has been without a GPS. A few iterations of setting the 20 MHz oscillator frequency are required, but mine has run for more than a week solid with less than 1 second drift after adjustment. Because one of my applications for WSPR will never have GPS, I may eventually build an accurate real time clock based on the ChronoDot module and an Arduino to simulate the GPS, but so far I have not seen the need. > > > > > > For the final output power supply I used a cheap switching regulator from eBay. Similar to: > > > > > > I use them because they are more efficient than the linear regulator. Less heat, and heatsinking, and the signal is not interfered with as far as I can tell. > > > > > > There are versions of the LM2596 regulator with a voltmeter now attached that I see on eBay which might be nice for setup. > > > > > > Yes, the manual for Hans kit and the WSPR documentation makes good reading. Enjoy. > > > > > > Paul KE7HR > > > > > > --- In QRPLabs@..., "Don" wrote: > > > > > > > > Paul, > > > > From what you said, a variable PS just for the final or finals might be interesting. Use a LM-317 and pot for regulator. Bad news yesterday. Was going th use my old FV-M8 for the GPS. Data out was good on scope, but no 1 pps output. Using it on other projects, I never needed this output. What a letdown! Checked it over and over. Nothing. Sparkfun shows FV-M8 retired, so went with the EM-406A. Guess WSPR will have to wait a few days. OK on questions. I should read the manual! > > > > > > > > Don > > > > > > |
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Re: Ultimate 2 QRSS no work
"Don"
Paul and others,
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You know, I think a newbie like me can easily take points out of context. I do remember seeing somewhere, probably not here, WSPR is the one mode a GPS module is "very important". But, now I see a bit differently. Off frequency can be dealt with by nudging crystals. And drift can be stopped just by a tiny heat sink on the DDS chip, which I've done. I'm expecting a module in next day, so I'll see what it does for me. Actually, I've tried WSPR a year ago with a Softrock RX/TX running about a watt, and trying to recall what all I did! Don --- In QRPLabs@..., "Paul KE7HR" <ke7hr@...> wrote:
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Re: Ultimate 2 DDS lamp flashing
"hellozerohellozerokl7"
Thanks Hans - I couldnt see anything wrong but for a while I thought I had a X connections somewhere - but when the serial and 1 pps lines into the AVR are single points I came to the same conclusion.
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Ive not got the NMEA or 1 pps working as of yet but about to plug in the lastest rev. Has anyone been successful with the Z3801A GPS with the Ultimate 2 or had to do a level conversion jobby? I see a circuit to translation from differential to TTL and may have to do that? Regards from Alaska and thanks for all the hard work. Laurence --- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
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Re: TX Problem
"andyfoad@..."
Hi Hans,
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Yes I had a sneaky suspicion something might have changed in 2.03. In the back of my mind seemed to suggest that in 2.02 it got shifted, but I blew my 2.02 chip up with a little accident I had (cough) so I couldn't confirm it ;-) I've got a good stock of 2.03 chips now just in case I have any more "senior moments". Doesn't bother me either way, I'm entirely content here with the versions I have, for me they are perfect. 73 de Andy --- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
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Re: U2 with V2.03 firmware working FB
John Randall
Make sure you get the correct heater for the job as these xtal specs are unknown and too much or too little heat will make it worse. Perhaps Hans can tell you the source and you can get the correct heater for it. ? Digitally signed mail - M0ELS From: Andy Cutland To: "QRPLabs@..." Sent: Wednesday, 31 July 2013, 17:23 Subject: Re: [QRPLabs] U2 with V2.03 firmware working FB
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Hi John, Yes the kit already sits in a nice polystyrene box but in the shack (garden shed) the temperature swing can be massive during a sunny day so even the polystyrene box isn't enough for stacking of the signal to be possible. Therefore an oven at around 40c will be required to keep things perfect in between gps frequency adjustments. 73's De Andy From: John Randall To: "QRPLabs@..." Sent: Wednesday, July 31, 2013 5:15 PM Subject: Re: [QRPLabs] U2 with V2.03 firmware working FB
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Its a lot cheaper to simply place a styrofoam sock over the crystal which will keep it nice and cosy. 73 John ? Digitally signed mail - M0ELS From: Andy Cutland To: "qrplabs@..." Sent: Wednesday, 31 July 2013, 17:11 Subject: [QRPLabs] U2 with V2.03 firmware working FB
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Just installed V2.03 and can report that this is the most stable version so far. I have soak tested it with the trimble gps unit on 28mhz and can confirm that on fskcw mode my U2 drifted only a couple of hz over a 24 hour period after 2 hour warm up. That will do me ! My next task is to oven the oscillator can for faster stability. My cunning plan is to use a spare 3.3v regulator as the heat source which will be switched on and off by a 2n3904 with a thermistor between base and emitter as part of the bias circuit. I did investigate purchasing an ovened oscillator but the GBP 250 price tag put me off somewhat.? I will let you know how i get on as
a homebrew oven for a few quid sounds much more appealing. 73's De Andy |
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Re: U2 with V2.03 firmware working FB
Andy Cutland
Hi John, Yes the kit already sits in a nice polystyrene box but in the shack (garden shed) the temperature swing can be massive during a sunny day so even the polystyrene box isn't enough for stacking of the signal to be possible. Therefore an oven at around 40c will be required to keep things perfect in between gps frequency adjustments. 73's De Andy From: John Randall To: "QRPLabs@..." Sent: Wednesday, July 31, 2013 5:15 PM Subject: Re: [QRPLabs] U2 with V2.03 firmware working FB
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Its a lot cheaper to simply place a styrofoam sock over the crystal which will keep it nice and cosy. 73 John ? Digitally signed mail - M0ELS From: Andy Cutland To: "qrplabs@..." Sent: Wednesday, 31 July 2013, 17:11 Subject: [QRPLabs] U2 with V2.03 firmware working FB
?
Just installed V2.03 and can report that this is the most stable version so far. I have soak tested it with the trimble gps unit on 28mhz and can confirm that on fskcw mode my U2 drifted only a couple of hz over a 24 hour period after 2 hour warm up. That will do me ! My next task is to oven the oscillator can for faster stability. My cunning plan is to use a spare 3.3v regulator as the heat source which will be switched on and off by a 2n3904 with a thermistor between base and emitter as part of the bias circuit. I did investigate purchasing an ovened oscillator but the GBP 250 price tag put me off somewhat.? I will let you know how i get on as
a homebrew oven for a few quid sounds much more appealing. 73's De Andy |
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Re: U2 with V2.03 firmware working FB
John Randall
Its a lot cheaper to simply place a styrofoam sock over the crystal which will keep it nice and cosy. 73 John ? Digitally signed mail - M0ELS From: Andy Cutland To: "qrplabs@..." Sent: Wednesday, 31 July 2013, 17:11 Subject: [QRPLabs] U2 with V2.03 firmware working FB
?
Just installed V2.03 and can report that this is the most stable version so far. I have soak tested it with the trimble gps unit on 28mhz and can confirm that on fskcw mode my U2 drifted only a couple of hz over a 24 hour period after 2 hour warm up. That will do me ! My next task is to oven the oscillator can for faster stability. My cunning plan is to use a spare 3.3v regulator as the heat source which will be switched on and off by a 2n3904 with a thermistor between base and emitter as part of the bias circuit. I did investigate purchasing an ovened oscillator but the GBP 250 price tag put me off somewhat.? I will let you know how i get on as
a homebrew oven for a few quid sounds much more appealing. 73's De Andy |
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U2 with V2.03 firmware working FB
Andy Cutland
Just installed V2.03 and can report that this is the most stable version so far. I have soak tested it with the trimble gps unit on 28mhz and can confirm that on fskcw mode my U2 drifted only a couple of hz over a 24 hour period after 2 hour warm up. That will do me ! My next task is to oven the oscillator can for faster stability. My cunning plan is to use a spare 3.3v regulator as the heat source which will be switched on and off by a 2n3904 with a thermistor between base and emitter as part of the bias circuit. I did investigate purchasing an ovened oscillator but the GBP 250 price tag put me off somewhat.? I will let you know how i get on as
a homebrew oven for a few quid sounds much more appealing. 73's De Andy |
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Re: Ultimate 2 QRSS no work
"Paul KE7HR"
I am on holiday up in the state of Washington and my WSPR beacon is running on 80 meters with 1 watt to a dipole up in the trees. I have been copied over 100 times overnight. I really don't think that GPS will help get more spots... The only thing it will do for you is try and keep the clocks in line and automatically set the grid square.
toggle quoted message
Show quoted text
The clocks can be zeroed in on with spreadsheets that are in the files section of the group. My "final" clock setting is 19,978,582 but yours WILL be different. My DDS clock is set to 125,001,739 but, again, yours WILL be different. Use the spreadsheets and do a few days into a dummy load to get things right before going on the air. Listen to WWV to set your clock, let it run for a day or so and note the offset. It only took me three days or so to zero in. Have fun and explore the group site. Paul (on the Olympic Peninsula) KE7HR --- In QRPLabs@..., "Don" <don1mh@...> wrote:
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Re: Ultimate 2 DDS lamp flashing
Hans Summers
Hi Laurence Does everything work fine when the unit is properly powered up? I noticed the same effect too. I don't think it is anything much to worry about. Modern LED's emit a small amount of light even at very low currents. Probably there is some kind of leakage through the AVR chip from the 1pps line or the Serial data line, and it finds its way to the 5V line somehow and allows some small current to flow. Something like that. I don't lose any sleep, worrying about it... as long as everything works as it should when power is applied etc.?
73 Hans G0UPL On Tue, Jul 30, 2013 at 8:55 PM, hellozerohellozerokl7 <hellozerohellozerokl7@...> wrote:
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Re: TX Problem
"john349624"
Thanks Hans.
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Mystery solved. --- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
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Re: TX Problem
Hans Summers
Hi Andy, John There was a request to keep the output on frequency and the TX going, in FSK/CW mode in between frames, except during the 13 seconds calibration, so that the temperature would be more constant and reduce the drift. This was put into v2.03. An unintended consequence was that on WSPR, the kit stays on frequency, though it is in key-up mode. However even in the key-up mode, some signal leakage does occur and I believe this is responsible for the effect you see.?
In v2.04 I do plan to eliminate this effect: I'll move the DDS off frequency or put it to zero frequency during key-up so that you don't see this effect. As soon as I get a chance to do this, I will. But there are only so many hours in the day, and they never seem really enough :-(
So in conclusion: just don't worry about it. It won't trouble WSPR decodes and I'll take care of it in the next firmware version, for anybody who still is worried about it.? 73 Hans G0UPL On Wed, Jul 31, 2013 at 8:47 AM, andyfoad@... <andyfoad@...> wrote:
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Re: Ultimate 2 QRSS no work
Hans Summers
Hi Don WSPR works fine without GPS. You won't get more spots with GPS or without it. GPS will calibrate your transmission frequency, and it also will keep your realtime clock accurate. Without GPS, the time would drift slowly. WSPR decodes will stop once the drift exceeds a second or two.
However if you measure the drift, you can compensate for it in the 20MHz system clock configuration setting by setting the accurate value near to 20MHz. Once you have compensated for the system clock drift, you should be able to run the kit for a week without intervention, according to reports.?
73 Hans G0UPL On Wed, Jul 31, 2013 at 1:34 AM, Don <don1mh@...> wrote:
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Re: TX Problem
"andyfoad@..."
I thought that Hans had changed the firmware to switch the DDS to I wonder if a bit of code got lost from the beta version - Hans ? Aha - did that feature get dropped in order to meet the GPS calibration procedures ? 73 de Andy |
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Re: TX Problem
"andyfoad@..."
--- In QRPLabs@..., "john349624" <g4pir.john@...> wrote:
Hmmm, I'd normally expect a decent bench PSU not to create the problem you've described. But at unless there's a problem with the PA stage then it does usually point to the PSU. You'll need about 120ma for the DDS+LCD and about the same for 3 x BS170's at 9v. Thought so ;-)
It's the same as I observe here. I thought that Hans had changed the firmware to switch the DDS to another frequency when the TX goes off, in order to make monitoring the tx frequency easier. I wonder if a bit of code got lost from the beta version - Hans ? Kind regards, Andy |
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Re: TX Problem
"john349624"
Hi andy thanks for the reply.
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PSU at the moment is a bench supply. When the kit is boxed up it will have its own 5v supply. As you said on your last reply it is the DDS carrier that i'm seeing after TX. So this is what happens. 1. Turn on the Kit. 2. Set Clock. 3. Set mode. 4. Start up. 5. No output On Watt meter. 6. First TX cycle I see 25dbm output (300mw or so) 7. Stop TX, Display returns to Clock and counting to next cycle. 8. I still see 7.6dbm output (5mw) 9. Next cycle starts output 25dbm. 10. stop tx , still 7.6 dbm output. So is this normal operation ? Regards. john g4pir. --- In QRPLabs@..., "andyfoad@..." <andyfoad@...> wrote:
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