WSPR 2.1, for I/Q SDRs

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k1jt
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WSPR 2.1, for I/Q SDRs

Hi all,

The number of volunteers for testing WSPR 2.1 has been overwhelming! Many thanks to all who have sent reports... Already you have helped me to identify a few bugs and to improve WSPR 2.10.

You can now download the Windows installation file for WSPR 2.10 r2165 from

http://www.physics.princeton.edu/pulsar/K1JT/WSPR2.10_r2165.EXE

Changes since revision 2158 include:

1. Fixed a bug affecting Tx sideband suppression and the "Reverse Tx I/Q" option. I believe these work correctly now: I have good Tx sideband suppression, and the "Reverse" checkbox works as it should.

2. Fixed a bug affecting the reading of "Rx noise" level during receive.

Setup procedure is the same as for r2158. (For those who did not receive my previous instructions, I have appended them at the bottom of this message.)

I reported before that by running my SoftRock RxTx Ensemble in parallel with my TS-2000, each with its own instance of WSPR, the SoftRock gives worse Rx performance by about 3 dB in reported S/N. Aldo, IW2DZX, has reported similar results. I have not yet identified the cause, but will be working on it.

A number of good suggestions have been made for new features or enhancements. I will be looking at those, also. Fair warning: I have many other obligations over the next few weeks, so please be patient!

-- 73, Joe, K1JT

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WSPR 2.1 Installation Instructions

Download and install WSPR 2.1 in the usual way. In this testing phase you may want to put it in a separate directory, so as not to over-write your existing WSPR 2.0.

Configure WSPR 2.1 as described in the WSPR 2.0 User’s Guide, http://physics.princeton.edu/pulsar/K1JT/WSPR_2.0_User.pdf , with the following specific additions for SoftRock RxTx Ensemble or equivalent:

1. On the Setup -> Station Parameters screen, you should select:

PTT method: CAT
Rig number: 901 SoftRock RxTx Ensemble

2. On the Setup -> Advanced screen, check "Enable I/Q mode". Depending on how you have wired your SoftRock, you may or may not need to check "Reverse Rx I,Q" or "Reverse Tx I,Q". (Mine does NOT need these boxes checked.)

3. The parameter "Fiq (Hz)" determines the frequency offset between the "Dial frequency" specified on the WSPR main screen and the frequency (times 1/4) of the Si570 programmable oscillator. The default value for Fiq is 12000 Hz; this puts the 200-Hz WSPR band 12 kHz above mid-band.

For example, in my system when operating on the 30 m band, I set:

Dial frequency: 10.1387 MHz
Fiq: 12000 Hz

This results in a commanded Si570 frequency of 40.506800 MHz

I have not followed the procedure to "calibrate" my Si570. Consequently, I found the resulting received frequencies to be off by 60 Hz -- so I checked "Enable frequency correction" and set the correction constants

A = 0.0
B = 5.92

This value of B was calculated from

B = (60 Hz) / (10.1387 MHz) = 5.92 ppm

Your calibration constant(s) will most likely be different.

Of course, you can use other calibration schemes, as well. Remember that for most effective use of WSPR, you will want your frequencies to be correct to within 10 Hz or so.

...

For those of you with other SDR receivers or transceivers than the SoftRock RxTx: I think everything in WSPR 2.1 should work for you, except for CAT control of frequency and T/R switching. You should be able to set your frequency manually, and use DTR or RTS on a serial port for T/R switching.