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Re: GPS behaviour very inconsistent
Tony Volpe
Keith, Could you say more about the battery backup you added? What is the exact voltage on your system? How is it different to what you had before? I have not been able to get my EM-406A to operate with the new kit, but it is working fine on the old one. In my case, the clock will not appear and the kit won't start when I set USE GPS to ON. If I set the invert GPS parameter to invert (which is wrong for the GPS, the clock appears, and the kit starts and will transmit on schedule, but the clock runs fast and within a minute or two is well out of sync with real time. This corrects momentarily when the transmit cycles end and then it runs away again.
If you have found a solution, I'd be well pleased. :)) The kit works well in every other way that I have tried, but I've only been using WSPR.
Tony G0BZB On 20 May 2013 21:43, Keith Maton <nentecular@...> wrote:
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Re: QRSS ARDUINO shield questions
"dd5cf_colin"
Hi Hans and Alan,
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Thank you both for the information and the links Alan. Have you any advice for me about question 1 of my last post: If I run the ARDUINO UNO on battery power can I connect it to GND and Vin (as recommend by the arduino website) through your QRSS shield? My contribution to the "BS170's in new kit PCB's - opinions please?" post is why not supply a couple of 2N7000's in a seperate bag and those OM's who are not confident about which way round the BS 170's go can have the choice. 73 Colin DD5CF / G1ZOS --- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:
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Re: Ultimate2 kit status summary-GPS
g3zjo
On 20/05/2013 22:27, Hans Summers wrote:
By 50%, you mean the duty cycle is 50%? If so, this would support my theory that this issue is related to very short pulse widths on some GPS modules.:-) . I don't know, I hoped you would. PPS < ???25 ns @ 50% was copied from the manufactures data. Its very short, I can't see it on my scope all I can get is a trigger from its leading edge so I knew it was there. 73 Eddie |
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Re: Ultimate2 kit status summary-GPS
Hans Summers
Hi Eddie?
By 50%, you mean the duty cycle is 50%? If so, this would support my theory that this issue is related to very short pulse widths on some GPS modules.
73 Hans G0UPL |
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Re: U2 step tests
g3zjo
On 20/05/2013 22:07, Hans Summers wrote:
Anyway I don't think we need to lose any more sleep over this stuff. I think I understand the problem adequately now.Hi Hans Jolly good. Personally I think it shows what we have found with WSR, the results on each U2 are inconsistent, Andy FTD had prety good linearity and my steps are not linear on 3.5MHz. Some of the steps, (now back using your settings and 5.5Hz) give the same no or very tiny shifts on several pairs of steps. All noted re bucket size but I do it see better the steps and the difference is consistent for each step and repeated accurately. Anyway irrelevant now if you have the full understanding so looking forward to the sorted version. 73 Eddie |
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Re: U2 step tests
Hans Summers
Hi Eddie ? I have increase the requested steps to 10 Hz total How did you increase the requested steps to 10Hz total? The FSK (Hz) size parameter is ignored here. In the custom message mode, the size of each step is always 0.5Hz. So if you have 12 steps, it should go from 0 to 5.5Hz always.?
I believe that the observations of only 8 steps being apparent on 3.5MHz are just a feature of the settings you are using in your spectral analysis program. If you changed the settings or used a different program I think that you would see the 12 steps correctly. I think at the settings you have, the resolution of the spectral analysis is limited to a "bucket" size of more than 0.5Hz, which mean you can't observe all the 12 steps accurately.?
Anyway I don't think we need to lose any more sleep over this stuff. I think I understand the problem adequately now. Regardless of whether it is there on 3.5MHz or not, it clearly arises as you go up in frequency and at 10m the steps are much too inaccurate or non-existent. I don't need any more experimental observations now, I think the experiments to date have been extremely helpful.?
Many thanks to Eddie and all those of you who have provided the observations. Now I have to just change the part of the code which calculates the DDS tuning word.? 73 Hans G0UPL |
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Re: QRSS ARDUINO shield questions
Hans Summers
Hi Colin As Alan said, there's a book see??for the details. People can still build and operate the QRSS Arduino shield without the book. But the book does contain a lot of other interesting things and would probably be useful for people who want to learn more. There's a huge amount of information on Arduino around the internet too.
73 Hans G0UPL On Mon, May 20, 2013 at 4:27 PM, Alan <g0rwb@...> wrote:
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Re: GPS behaviour very inconsistent
Keith Maton
¿ªÔÆÌåÓýSince I added battery backup to my GPS module at the weekend things are more consistent.? When I apply power, the clock shows and it's normally accurate to within a few seconds. ?I put the GPS invert to off and the clock shows correct. ?I put the invert back to on and it stays correct without drifting. I've been running WSPR for over 24 hours on 30m/20m with no problems. I'm very pleased to have been seen in VK land on 20m WSPR this afternoon. 73 Keith, G6NHU -- On 17 May 2013, at 10:35, Keith Maton <nentecular@...> wrote:
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Re: U2 step tests
g3zjo
On 20/05/2013 07:56, Hans Summers wrote:
I think that at 80m, some of what you observe is just features of the decode process on such a strong signal. Can you put in some attenuation so that the line is thinner?Well I am still trying to make 8 beans equal 12. No matter how yo look at it there are only 8 distinct levels on 3.5MHz Eddie |
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Re: QRSS ARDUINO shield questions
"Alan"
Hans has contributed three chapters, including one on QRSS and one on the multimode transmitter shield, to the new ARRL book 'Hamradio for Arduino and Picaxe'. It's well worth a look, it would probably answer your questions.
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If I've read it correctly, switches 1 and 2 give a value from 0 to 3 to select modes None/QRSS/FSKCW/DFCW, similarly switches 3 and 4 give speeds of 12WPM/QRSS3/QRSS6/QRSS10. Loading Arduino sketches into ATtiny chips is covered here: I think you will need an ATtiny44 or ATtiny84. The 8-pin ATtiny45/85 types don't have enough pins for this application. Hope this helps. Regards, Alan G0RWB --- In QRPLabs@..., "dd5cf_colin" <jobaco@...> wrote:
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Re: Silk screen drawings
Leigh L Klotz Jr WA5ZNU
I started the 2n7000 wikipedia page! Leigh/WA5ZNU On May 19, 2013 11:39 PM, "g3zjo" <g3zjo@...> wrote:
> To quote from Wiki:- > >> The 2N7000 and BS170 are N-channel, enhancement-mode MOSFETs used for low-power switching applications. The two are nearly identical except that the leads are arranged differently and the current ratings are somewhat different |
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QRSS ARDUINO shield questions
"dd5cf_colin"
Hi Hans and all,
I have a couple of questions about the arduino shield. 1: If I run the UNO battery power can I connect it to GND and Vin (as recommend by the arduino website) through your QRSS shield? 2: I have looked through the sketch to find out which DIP switch does what but due to my limited knowledge I cant make head or tail of it, can you tell me the various switch positions / modes? at the moment I have only switch 1 in the on position this seems to be QRSS 3. 3: I think it must be possible to upload the sketch to a ATtiny chip or similar (sorry lack of knowledge again) and breadboard the QRSS shield with the chip, what sort of chip would I need ? 73 Colin DD5CF / G1ZOS |
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Re: U2 step tests
g3zjo
On 20/05/2013 08:43, Barry Chambers wrote:
Are you running out of resolution in step size here? What's the actualI think it is more like 0.08Hz min I have reduced signal level and the blow up of the width, Thing is I cant write on those.:-) There is an anomaly repeated every time on steps 6,7 and 12 where the actual width of the signal is greater this can be seen by the with of the waterfall peak (if you guys looking at capture are lucky enough to catch it) is the DDS indecisive trying to achieve a freq and deviating (aliasing)? Another way of observing is to watch the time spent at each frequency by the waterfall peak, I can do that of course and can see the double time at some steps. Also I can see the wide peak at 6,7 which stays on the same freq for twice the unit time. Eddie |
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Re: U2 step tests
Barry Chambers
On 20/05/2013 08:32, g3zjo wrote:
On 20/05/2013 07:56, Hans Summers wrote:Hans, EddieI think that at 80m, some of what you observe is just features of theHi Hans Are you running out of resolution in step size here? What's the actual min resolution the DDS can give with a 125MHz xtal? -- 73 Barry, G8AGN |
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Re: U2 step tests
g3zjo
On 20/05/2013 07:56, Hans Summers wrote:
I think that at 80m, some of what you observe is just features of the decode process on such a strong signal. Can you put in some attenuation so that the line is thinner?Hi Hans The wide line is due to the resolution which I have pushed up, to make it clearer in fact. Yes there is some inevitable spread. Of course I will add some attenuation for you and see what I can do. However please observe and consider:- I have increase the requested steps to 10 Hz total There are 12 steps in the message Only 8 discreet steps are present The total pattern does not achieve the 10Hz expected Each step will be 0.833Hz The shift achieved is around 6Hz 8 steps times 0.833 equals 6.666Hz I am glad I did the test then I was not sure at what stage you were at in the solution. 73 Eddie |
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Re: U2 step tests
Hans Summers
Hi Eddie I think that at 80m, some of what you observe is just features of the decode process on such a strong signal. Can you put in some attenuation so that the line is thinner?
I think the tone spacing is probably Ok on 80m, once you do that. The problems come in, at the higher bands where too much precision is lost. 73 Hans G0UPL
On Mon, May 20, 2013 at 7:50 AM, g3zjo <g3zjo@...> wrote:
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U2 step tests
g3zjo
Hans / Lads
I have increased the resolution of my Grabber for clearer understanding of the step tests. Currently on 3.5MHz band and the frequency indicated. The 3.5MHz band produces decodeable WSPR but the shift is not correct. I have annotated a blow up of the steps which is attached and will be in my Group Folder. 73 Eddie G3ZJO |
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Re: Silk screen drawings
g3zjo
¿ªÔÆÌåÓýOn 19/05/2013 22:30, Hajo Dezelski wrote:I was a little bit irritated about the various comments concerning future PCB boards.Hi Hajo I see your point but but I see it totally differently. The board layout and silk screen is not WRONG and does not need alteration which would cause confusion. Everything is correct for the 2N7000, the BS170 can be supplied as an alternative and adequate information is provided for the correct orientation of this substitute. We can only get irritated with the manufacturers of the devices if we wish lazy people to be able to mindlessly thrust devices in any way round. Heat sinking as you say is not essential and dissipation can be dealt with by extra devices inserted in the positions provided. 73 Eddie G3ZJO To quote from Wiki:- The 2N7000 and BS170 are , used for low-power switching applications. The two are nearly identical except that the leads are arranged differently and the current ratings are somewhat different |
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Silk screen drawings
Hajo Dezelski
Hello Hans, I was a little bit irritated about the various comments concerning future PCB boards. Your project is not a one night stand. It is here to stay and to get developed by you and the community. On the subject of heat sinks I am biased. These transistors are build to like some heat ... 72 de --- |
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