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
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--- In QRPLabs@..., "Paul KE7HR" <ke7hr@...> wrote:
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" <don1mh@> 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" <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" <don1mh@> 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
