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WSPR TX Time Charts
I put a series of WSPR TX time charts in the Photos section. They show the time slot for various start times and frame settings. For the 00 start time, the chart will be valid after the first hour
By "Paul KE7HR" <ke7hr@...> · #1327 ·
DDS Oscillator spreadsheet
I put a spreadsheet to help calculate the true DDS oscillator frequency in the Files section. It allows a normal operating frequency to be used instead of an out of band frequency. Make sure that
By "Paul KE7HR" <ke7hr@...> · #1326 ·
Re: GPS behaviour very inconsistent
Wire the back up battery line I think it is to the 3.3vdc supply. Then just wire the data and 1pps direct to the U2. No pull up / down / sideways resistors - no nothing ;-) Just make the small
By "andyfoad@..." <andyfoad@...> · #1325 ·
Re: GPS behaviour very inconsistent
Hi Barry, My up501 has just arrived from taiwan and am eager not to blow this one up ! Did you place any resistors on the unit and if so what value did you use. I will be supplying the unit from a
By Andy Cutland <gj7rwt@...> · #1324 ·
Does anyone use Hell / Dx Hell ?
Does anyone use these modes at all for beaconing or MEPT's ? (I see plenty of activity withthe Slow Hell mode, since that can easily be seen on a standard speed QRSS grabber.) 73 de Andy
By "andyfoad@..." <andyfoad@...> · #1323 ·
Re: Slow Hell with U2 and U1
Yep, been there seen that. Yes indeed. 73 Eddie
By g3zjo <g3zjo@...> · #1322 ·
Re: Slow Hell with U2 and U1
Hi Eddie Thank you for your insight into the slow Hell.. math. Trying to isolate the issue, I recently I mapped some Hell figures into the special messages mode and was pleasantly surprised to find
By "Dave" <airdry@...> · #1321 ·
Re: Slow Hell with U2 and U1
Hi Dave I think you are the only person to have mentioned Hell Modes on the U2, and there have been no replies. During initial tests I abandoned the Hell Modes early on as all results I was getting
By g3zjo <g3zjo@...> · #1320 ·
Re: U2 Final Voltage
Hi, I have not checked the topology chosen by Hans for the PA and this is just for comparison. With the KD1JV ATS/MTR series of transceivers, we achieved 5W from 3 Bs170 at 12V on 20 meters CW. Power
By "Yannick" <xv4y@...> · #1319 ·
Re: U2 Final Voltage
Thanks, Dave. I have a bag of BS170 and don't see marks to identify the maker... I put a heatsink on for good measure and also a variable PA supply separate from the supply that feeds the board.
By "Paul KE7HR" <ke7hr@...> · #1318 ·
Re: U2 Final Voltage
Has anyone tried running 3 x BS170's at 12v yet AND measured the output at 28Mhz please ? (Please note, if you have nit used 28Mhz yet then you might need to tweek the blue DDS pot to get it
By "andyfoad@..." <andyfoad@...> · #1317 ·
Re: U2 Final Voltage
Sorry that should be 830 mw max dissipation on the bs180 to-92 Dave
By "Dave" <airdry@...> · #1316 ·
Re: U2 Final Voltage
Paul I was running a matched set of 3 Fairchild transistors and they are rated for 830 ma max and can take quite a bit of heat max 150c which should put over 2 watts out. I am using a small wattmeter
By "Dave" <airdry@...> · #1315 ·
U2 Final Voltage
My U2 was putting just over 12 volts peak to peak into 50 ohms on 80 meters using a 5 volt final drive (LM2596 switching regulator) with one final. I installed the other two finals and only got an
By "Paul KE7HR" <ke7hr@...> · #1314 ·
Slow Hell with U2 and U1
Hello All I am really enjoying this kit and have had great results on WSPR and other modes. From Canada on 20 meters the U2 easily Wsprs around the world and the frequency calibration is very stable
By "Dave" <airdry@...> · #1313 ·
Re: QRSS Arduino Shield Switches
Dale, be sure the Shield does'nt get claustrophiobia. It seems a common problem with homebrewed equipment these days. Probably something to do with global warming or summat. :-)
By "Mike W" <mike@...> · #1312 ·
Re: QRSS Arduino Shield Switches
Thanks Hans I set the switches and started Argo and everything seems to work properly. Now I need to put it into an enclosure and put it on the air. Thanks again 73's Dale W0IR From:
By "w0r" <w0ir@...> · #1311 ·
Re: QRSS Arduino Shield Switches
Hi Dale In the sample sketch provided, two of the switches (S3, S4) set the speed: // Read the switches, to set the mode and speed mode =
By Hans Summers <hans.summers@...> · #1310 ·
QRSS Arduino Shield Switches
Can some on tell me what the switch setting should be on the QRSS Arduino Shield. I believe I should be running the board QRSS3. Thanks Dale W0IR
By "Dale" <w0ir@...> · #1309 ·
Re: Wire guage on LPF's ?
Yes Andy, that was my thinking as well. What I have done on other boards is clear the hole with a piece of the Enamelled Copper Wire with the end cut across at 45degrees, it seems good enough to
By "Colin XSD" <sacreddog@...> · #1308 ·