[PPRAANet] PPRAA Remote Station PSK31 Usage

[Jim Harris via PPRAANet]

Hi everyone.
If you are using the club's remote station for PSK31 you must exercise extra caution to prevent over driving thereby causing excessive Inter Modulation Distortion (IMD).  The excessive IMD causes interference to others in the PSK31 sub-band.  The power level of the TS-450 transceiver at the remote station is set at 100 watts and cannot be adjusted lower due to the lack of a CAT command available to control the power.  Typically for PSK31, where the power can be controlled it is set for 35 watts or less.  This level is necessary to help control the IMD.  An alternative method and recommended for the remote station is to reduce the drive setting in your client (local home) computer's sound system to no more than "10" to "15"  when the maximum available level is "100."
When you make a contact always ask for and give an IMD report along with an RST report.  Most PSK31 software provides and IMD level somewhere near the bottom of the program's window.  In most cases about -21db or greater (higher number) is acceptable.  Note that is a negative number so a higher number is actually a lesser (lower) value and that is good in this instance.
If you want to be really safe email me to test your modulation.  I have a PSK31 IMD meter that I can test your transmitted signal and determine your IMD.  That is as long as the remote station is at my QTH.  If it moves to another location getting an on air report is the best alternative.  My email is jim.w0em at yahoo.com.
Remember you are responsible for the quality of your transmitted signal from the remote station.  ARRL Official Observers (OO's), and I suspect the FCC as well, like to hangout on the PSK sub-bands because it is easy to find violations there.
I will incorporate the above into the next revision of the remote station tutorial.  If present users want an updated copy please email me.
For anyone wanting to experience remotely operating the station email me and I'll send you the tutorial to help you get started.  Those who have used the station are very pleased with it including operating JTS.
Thanks and 73,
Jim H.,  W0EM