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Understanding Propagation

Station Equipment

Test Equipment

  • Fluke 77 DVM (circa 1970, my old friend!)
  • NANO VNA Network Vector Analyzer
  • Looking for an inexpensive 100 Mhz dual trace storage oscilloscope.
  • NOTE: The RSP1a SDR makes a fine spectrum analyzer to sample transmitted signal.  My current antenna is selected by a switch box, then routed through the MFJ 1708B SDR TR Switch to the RSP1a and the Yeasu FT10Dx transceiver.  When in transmit there is just enough RF energy still present to provide the RSP1a with a very usable sample.  Good way to check for modulation and spurious emission (my first harmonic is less than 30 db down - GOOD!)  Tuning my audio card volume and WSJT-X's power control shows that for FT8 mode I can run the selected audio card at full volume, and the program power level at 100% without distortion and that I do not have to apply any wave shaping to produce a clean transmit signal.
    • 20210730 I captured this screen shot from the Spectrum Analyzer app running on the RSP1a.  Conditions: WSJT-x FT8 Tune mode with transmit frequency set to 1000 Hz, Power 100%, into Palomar 55 antenna, sampled by RSP1a inline via MFJ 1708B.  First harmonic is -33db 4th harmonic is -50.5db.  The signal is averaged over 20 sweeps.


  • Skimmer (not until it works with my SDR or another inexpensive one).  Skimmer is expensive - but it could be worth it since there are few reverse beacons near me.  But not until I have a proven antenna system ...
  • DXLabs - Best radio control, DX, Contesting software, but it needs a native CW decoder!
  • WSJT - The best way to 'do' FT-8 etc.
  • JTAlert - Adds serious functionality to WSJTx for things like 'worked before' and 'Calling You'.
  • NOTE: As of July 2021 I have configured WSJTx and JTAlert to cooperate and control FT8, logging (both local and LoTW) and spotting.  Working on how to automatically and timely update LotW and QRZ logs.
  • CWGet  - Works off the sound card, so it can work with DXLabs Winwarbler. 
  • CHIRP - Allows programming HT's to the same channel (frequency) etc. even if they are different model numbers from different manufacturers. But its a bit 'clunky' - I may have a look at creating the same functionality using some other tools and database(s).

Project List

Antenna Analysis
VNA analysis of my antennas - or - Learning how to use VNA Windows software.

Alpha JPole Jr Install and Test
Using a 30' flag pole to 'fly' a wire antenna and stay under the radar (maybe).
As well as how well it works, and how much sensitivity it has to installation direction.
Comparison to Wolf SOTA vertical and other antennas.

Transact (or something) the DXLabs and WSJTx MS Access log databases on JWIN into MySQL tables on JMAC so I can archive, and manipulate, display etc. outside of the applications.  See if AppGini can ingest 'em?  Otherwise use Open Office Db to enumerate and export?

Shack Grounding
  • Pending ground rod install. 
    • Presently using 3rd wire ground which may be a significant fraction of wavelength because of the way my electrical distribution is laid out.
      • Document RFI using RSP1a and Windows screen shots to compare before and after grounding effects.
    • Install 8' ground rod - leave enough to attach a high lift jack to extract, near the NW corner of the shack. 
    • Pull #12 bare CU to the operator position and distribute connections to radio equipment by replacing the current 3rd wire lug.
    • Pull #12 bare CU to each flag pole and VHF mast, drill, tap and lug to base of pole.
    • Next routine maintenance bond across each pole joint.
  • Lightning Ground
  • Signal Ground
  • EMI Ground and Shielding (I've got a great large (1490Khz/1KW) AM ground wave transmitter 500 yards to my East).

Radio Continuity of Operation

  • New battery for UPS
    • Power OP strip from UPS (JMac & display, JWin & displays, ext drives, HF, VHF & UHF radios, HT charger.
  • New automotive/deep cycle battery for transmitter(s)
    • Solar charger.
    • Switch radio over from commercial to battery.  Temporary immediate phone, CW only.
    • Switch entire shack to generator (change 30A source fm commercial to genset), Temporary all modes.

Completed Projects