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Re: WSPR on 28MHz
Hans Summers
Hi Eddie Many thanks for all your efforts in helping to collect evidence to track down this problem. I know it might be a little frustrating but thanks for persisting!
I suspect that there might be some arithmetic issue in my code which reduces the accuracy of the calculation when the frequency is high. More specifically, when the shift frequency becomes smaller relative to the baseline output frequency.
If you have time, I think that a very useful test might be a ramp from 0 to 5,5Hz shift (say), at 0.5Hz increments. A staircase, really. This would show very clearly any issues with inaccuracies of the steps, and clarify immediately on what bands and frequencies they started to become a problem.?
I am referring to the stuff in section 8 of the manual (page 28). A customised message to produce a staircase of shifts from 0 to 5.5 Hz, with 5 seconds spent on each stair. The staircase will take 1 minute. This will make it much easier to see what is going on than images of WSPR, which spends only a short time on each frequency so looks messy on the Argo (etc) display.
The required mode should be FSK/CW, and the Message string contains the speed and the shifts, with an asterix ' * ' character to start and end it. So it should be *050123456789AB* for the described ramp.
73 Hans G0UPL On Sat, May 18, 2013 at 11:33 PM, g3zjo <g3zjo@...> wrote:
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Re: WSPR on U2 tests, 28MHZ WSPR solved I think.
Hans Summers
You can get a pure unmodulated carrier by setting FSK (Hz) to 0 and using FSKCW mode with any message. ?
Ok, I will see if there is space! 73 Hans G0UPL |
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Re: WSPR on 28MHz
g3zjo
Further update on this problem.
G0FTD seems to have intermittent thin WSPR data trace and no de-codes on 28MHz but has seen a decode or 2 of his own signal after fiddling. My unit is absolutely consistent with its performance. Further tests here and measurements reveal that that WSPR Data spacing is totally wrong. At 7.00MHz the difference between tone 0 and tone 3 is 10Hz this decodes because of WSPR's tolerance, as we increase the frequency the tone spacing gets smaller, I am not sure yet where it gets about right but after 21MHz it has got too small for it to de-code. At 28MHz it is down to around 4Hz the WSPR data is all there but its noticeable that Data 3 occupies the Data2 frequency. If the frequency shift variation is linear, let us assume it is, then:- 7MHz = 10Hz 10.5MHz = 9Hz 14MHz = 8Hz 21MHz = 6Hz 22 MHz = <6Hz 28MHz = 4Hz If I had not already established the point where decodes fail it could be predicted from the table above, when the spacing is less than 6Hz ie 22MHz. Additionally the only frequency where it is right is 21MHz. Tomorrow I will check the theory by measuring at 21MHz. Eddie G3ZJO |
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Re: WSPR on 28MHz
g3zjo
On 18/05/2013 20:16, Philip wrote:
Did a couple of hours test on WSPR 28MHz earlier Thanks Philip Glad yours works on 28MHz, knowing that you use outboard LPF was an influence for my test without the Output FET powered in case there was feedback. Your report puts us back into confusion but we love the challenge really don't we. 73 Eddie G3ZJO |
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Re: Message Error /B
"Chris D"
Sounds great Hans. Thanks for all your work, service and offering these kits at very reasonable prices. Cant wait to get my U2 built.
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72, Chris KQ2RP --- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
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Re: WSPR on 28MHz
"Philip"
Did a couple of hours test on WSPR 28MHz earlier
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Got a few spots which considering the band conditions and my Windom's reluctance to tune on 10 meters was a result.. The PA FET gets hot on this higher band though....much too hot.. Not bothered by this as my second kit will be boxed with the DDR feeding a different PA altogether and I will be loosing the FET stage. Anyhoo, it got out... Screen grab here... Philip G4JVF --- In QRPLabs@..., g3zjo <g3zjo@...> wrote:
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WSPR on 28MHz
g3zjo
Hi Hans
I tried various setting of the calibration, clutching at straws again, Andy FTDbhas negative values ie. 124,999,xxx mine is 125,000,555 there was no improvement in the narrow 3 Unit WSPR outputted. I have tried extra decoupling of the DC supply at the DDS pins, no difference. I have eliminated any possibility of the Output stage feeding back to the generator circuit by removing the LPF and the supply to the output devices. I am now just using the DDS Module output. Measurements of the output 'Square wave' which is actually sine I think the module is rated for square wave use only to 1MHz from memory. TX'ing WSPR :- 18.126100MHz - 7.0V pp, 19.126100MHz - 6.5V pp, 20.126100, 21.126100MHz - 6.0V pp, 22.126100MHz - 22.126100MHz By the time it get to 28MHz it is around 4.0Vpp but I think this is irrelevant, what is happening to the signal generation process is more relevant. I stopped the measurement here because the fold over point is between 21MHz and 22MHz. At 21.126200MHz WSPR normal height and 4 Unit WSPR which decodes is generated. At 22.126100MHz the 'fold over has taken place' the 4th data Unit frequency is absent, I don't think it is an overall compression of the data shift. Attached and destined for my Files Folder is a Capture which clearly shows a normal transmission at 21MHz followed by a cramped one at 22MHz. The Grab is straight from the screen in real time no cutting pasting etc. has been done so the results are obvious. Clearly something is happening at this point in the code, arithmetic error or whatever. Posted to the Group. Please how many Ultimate 2's are there that are OK on 21, 24 or28MHz, there do seem to be some reports from users. Can someone confirm the above 'fold over point'. We need more facts for Hans to investigate the problem. Andy FTD your requested Set Up Mode........Just press the Left button whilst WSPR is being sent, it goes into Sig Gen Mode like at the end of the 21MHz Trace in the Att.. 73 Eddie G3ZJO |
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Re: PA problem on new QRSS TX, some progress ;-)
Tony Volpe
Ok Hans. I don't think my efforts here will be terribly helpful. I made the circuit (ugly style) and I have a problem with it. It had no efect. Listening with a walkman earphone, I can hear the 'tick, tick' of the 1pps on the input to the diode and on the output too, but at the collector of the transistor a general purpose NPN, bc548, I get no ticks at all, just a hiss. I checked the component values; they are exactly as specified. I changed both the diode and the transistor. The 100n was a typical low tolerance brown capacitor marked '104'. I tried a variety of diodes including typical small signal type 1n4148. It had both ground and 5 volts connected, and I could hear the tick on the base but nothing on the output. I treble checked the pin outs on the transistor.
Sorry. I'll try again with it tomorrow. Tony
On 18 May 2013 11:16, g3zjo <g3zjo@...> wrote:
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Re: WSPR on U2 tests, 28MHZ WSPR solved I think.
"andyfoad@..."
Yep. Odd thing is I decided to put the rig live on 10m and the
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trace went funny. So it wasn;t the DDS ref afterall then. Just plonked it on 30m now. Whaddya know - I can see all 4 bit streams for the 1st time. Gonna leave the nude pcb running live for a few hours on 30m while I go out. Excuse the drift whilst its in the nude ;-) --- In QRPLabs@..., g3zjo <g3zjo@...> wrote:
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Re: WSPR on U2 tests.
Barry Chambers
¿ªÔÆÌåÓýOn 18/05/2013 13:15, g3zjo wrote:
? I've had the U2 kit working well on 20m WSPR (but without the GPS which still doesn't work here?). The kit still only has a single FET at 5v as the PA and the antenna is a "loop" made up of two pieces of wire each about 7 inches long and connected at the far end by a 47 ohm resistor - it's really meant to be a matched load but because the wires are arranged to form a rough circle, it works as an antenna! Best dx so far is over 800km. -- 73 Barry, G8AGN |
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Re: WSPR on U2 tests, 28MHZ WSPR solved I think.
g3zjo
¿ªÔÆÌåÓýOn 18/05/2013 13:26, andyfoad@... wrote:I've just had a thought to recheck my 125Mhz DDS clock frequency.Odd. As such calibrating will / should do nothing to the signal data as long as you are in the WSPR window which you can see for yourself anyway. The GPS does it spot on anyway. OK test in my mind, silly but gotta do it. Still looks like 3 data bit streams but it decodes now !No must be 4 data Units, Joe Taylor told me off for calling them bits :-) :-) :-)?? He got the same sort of answer though, you know what I mean. 73 Eddie |
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Re: WSPR on U2 tests, 28MHZ WSPR solved I think.
"andyfoad@..."
--- In QRPLabs@..., g3zjo <g3zjo@...> wrote:
Oh no, not another gong ;-) I've just had a thought to recheck my 125Mhz DDS clock frequency. I did notice a shift by 25Hz when I plonked the heat shieled on the DDS module but didn't think anymore about it. Just rechecked and recalibrated it as close as I could using just the expected beat note from the RX to Spectran, so it's still not perfect until I calibrate using my proper freq counter. Lo and behold I know get a 6Hz wide trace and 28Mhz decodes properly. Still looks like 3 data bit streams but it decodes now ! Hans: Any chance the next software upgrade can have a TEST menu on it, a bit like the old MK1 whereby you can have just a steady carrier output only, free of anything being applied to it so that we can do the following easier - U2 is on and left to stabilise. I always assume a warm up period with anything of 30 mins. My xtal in the Mk1 takes 20-30 mins to heat stabilise. Then once we're happy of the warm up period the TEST mode can be invoked, the user's frequency counter can measure the actual RF out and then the DDS ref freq setting can be altered ? Actually it might be a nice extra to have a TEST2 mode, that ramps up and down the WSPR data bit stream freqs so that it's easy to see what's happening by eye. As I'm typing this I have the AF output from the FT817 across the room and I'm typing this message on the laptop. WSPR is running on the lappy and being picked up by the internal microphone. WSPR software is showing me a string of decodes on 28Mhz even though there's a bit of drift caused by the U2 kit being naked on the table top! So far so good. But lets be careful here, all our collective posts are being sent almost real time so it's easy to make mistakes or give the wrong impressions. Just so long as we realise that ;-) 73 all de Andy |
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Re: WSPR on U2 tests.
g3zjo
On 18/05/2013 12:19, andyfoad@... wrote:
I've retitled this thread, since to the best of my knowledge thereGood idea. I have just seen / heard seen a WSPR signal on 28.126167MHz, does any one here own this signal. I could hear it clanging and banging just like my U2 on 28MHz and the signal did not decode. WSPR should not clang and bang when heard at a distance, OK local copy of such digitally generated signals may produce clicks. BTW 28MHz WSPR has been romping in all night last night and today the only pause in Spots of ny 200mW was about 30 mins before 01:30 UTC. 73 Eddie G3ZJO |
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Re: WSPR on U2 tests.
g3zjo
¿ªÔÆÌåÓýAh thank you Sir FoadI was just perfecting the knot in this 6feet of rope I have attached to the rafters in the shack. I shall now either put it away or send it in the post to Hans. Hans, its all your now, sorry. Do we have a batch of duff PIC's by another name because they are made by another manufacturer and are after all a bit different. :-)? :-) Shut up Eddie. 73 Eddie G3ZJO On 18/05/2013 12:19, andyfoad@... wrote: ? |
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WSPR on U2 tests.
"andyfoad@..."
I've retitled this thread, since to the best of my knowledge there
is no longer an issue with the PA on 28Mhz once the DDS pot is given a little tweak. Now I've done some tests on WSPR. 18Mhz: Using Spectran as a signal viewer I can see the WSPR trace. It looks like the right bandwidth. It decodes OK. But it still looks like there's on 3 data bit channels rather than 4. Maybe all 4 are there but the spacing is a bit narrow and this difference can't be viewed properly on Spectran ? 28Mhz: Trace looks skinny. Looks like only 2 data bit channels. Cannot any any decodes at all. With only two data sets here it's difficult to make assumptions, but there is an inference here that the bandwidth is narrowing the higher you go in frequency. So by the time you probably get to 10Mhz where I suspect most users are you would probably see all 4 data bit channels correctly spaced. Hope this helps lads.. Vy 73 de Andy G0FTD |
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Re: PA problem on new QRSS TX, some progress ;-)
g3zjo
On 18/05/2013 09:33, Hans Summers wrote:
PIC are a particular manufacturerYes I know all that, but you knew exactly what I meant and in my engineering circles we always bandied terms about, quickest simplest reference term is PIC and an SI570 does digital synthesis generation of signals and so it can be a DDS if you like, sorry this is OT and silly. Back to the Ultimate 2. With it Field Effect Switching Devices not PA Transistors. 73 Eddie |
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Re: PA problem on new QRSS TX, some progress ;-)
Hans Summers
Hi Eddie?
No no it's not such a debate. This is just a simple one. PIC and AVR's are both micro-controllers, quite similar, they are just different families from different manufacturers. It's like BMW and Mercedes. They're both cars. But different manufacturers, and a different range of models in each kind. If you called both cars, that would be fine. But if you called a BMW a Mercedes it wouldn't quite be correct. So it is with PIC's and AVR's.
PIC are a particular manufacturer, see?
AVR's another, see?? 73 Hans G0UPL
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Re: PA problem on new QRSS TX, some progress ;-)
g3zjo
¿ªÔÆÌåÓýOn 18/05/2013 08:54, Hans Summers wrote:Oops yes, checked that it, is v2.01. It was late last night when I decided to drop frequency in steps until WSPR started decoding and when it was not far different to what I remembered reading in the blurb it seemed a bit of a coincidence. Oh don't start that. :-)? Shall we call them both Non PC (Personal Computer) Processor Devices, like the guy who insisted its not computer less WSPR when you use a PIC because its a microprocessor. 73 Eddie |
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Re: PA problem on new QRSS TX, some progress ;-)
Hans Summers
Hi Eddie & all Many many emails are hitting my email box, as well as the ones coming through this forum. Many topics to consider. So please excuse me if I am delayed, or confused, etc :-)
?
On this particular point, Eddie - the "problem frequency of the V2 version if the PIC": this is NOT related!! The v2.00 version issue was with a SYSTEM clock over 16,777,216MHz - means the crystal frequency of the microprocessor, i.e. the 20MHz crystal. NOT a problem with the OUTPUT frequency setting. Furthermore, the problem manifested itself as incorrect WSPR timing, not frequencies. So that is entirely unrelated. Sending you a new processor won't alter that. In any event you have v2.01, as does 100% of everybody who bought a kit, because no v2.00's were programmed. That problem was found already during beta testing. Anyway you can see that by observing the screen at startup - it will say v2.01, which is the only version out there at the moment!?
So unfortunately, whatever problems we have to solve, v2.00 vs v2.01 is NOT the solution :-( Also note that it is an AVR processor, not PIC :-) Still contemplating... 73 Hans G0UPL |
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