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Mini Dragon Group (ages 6-7)

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John Duran
John Duran

Signal-to-noise Predictions Using Voacap Pdf Download _TOP_

Specify the Transmit antenna gain using the Tx. Site Antenna Gain entry field. An isotropic antenna is assumed for P2P predictions. The default value of 2.16dBi corresponds to the gain of a dipole over an isotropic radiator.

Signal-to-noise Predictions Using Voacap Pdf Download

Specify the Receive antenna gain using the Rx. Site Antenna Gain entry field. An isotropic antenna is assumed for p2p predictions. The default value of 2.16dBi corresponds to the gain of a dipole over an isotropic radiator.

Specify the Transmit antenna gain using the Tx. Site Antenna Gain entry field. An isotropic antenna is assumed for p2p predictions. The default value of 2.16dBi corresponds to the gain of a dipole over an isotropic radiator.

The combined method makes predictions based on the sunspot number, comparing all cycles recorded since 1749, combined with an assessment using the the geomagnetic index (aa). The geomagnetic index, 'aa', is an indicator of the level of future solar activity. For this reason, the Combined Model may produce superior results when passing the Solar minimum.

In the VOACAP literature, a value of 3 degrees is also commonly recommended, as it can be a common lowest angle for arriving skywave signals due to the roughness of the terrain. Also, 3 degrees may be a good choice if your antennas are not located in a flat, unobstructed area. And if you are using isotropic antennas, you should avoid huge amounts of antenna gain at angles below 3 degrees. You are encouraged to experiment between 0.1 and 3 degrees to see differences in predictions, using different antennas.Coverage Area SettingsFrom the usability point of view, I feel that it makes sense to allow the user to enter some input values separately for coverage maps. You can choose the year, month, the UTC time, the plotting time range (Range), the band, as well as the TX and RX antennas.At "UTC", choose the start time for your maps. The default is the current UTC hour.Also for "Range", choose the time period for the maps to be plotted on screen. The default is 1, i.e. the map for the current hour. You can choose time periods of up to 12 hours, so to cover a 24-hour period, you will only need to make two runs. Unfortunately, running and plotting 24 hours, or 24 coverage maps, at one go takes a considerable amount of time and processing power, and may result in a server connection time-out, hence 12 hours is the limit. Currently, even running more than 6 hours may lead to a time-out on the server.Propagation Planner SettingsThe "DX Sites" allows you to choose from either CQ Zones or ITU Zones as well as all DXCC countries or DXCC entities by continent. Propagation Planner predictions use all the point-to-point settings as their input values, e.g. the Antennas, SP/LP selection and the Es setting, TX Mode & Power.

NVIS propagation may be used to cover an area with a 200 km radius using low power and simple antennas [4]. As can be derived from the measurements in [8], a modest transmit power of 20 W in a dipole antenna will produce more than 30 dB signal-to-noise ratio (SNR) in a 3 kHz bandwidth, which is sufficient for data transfer speeds of at least 8 kbps, possibly even 16 kbps [9]. This SNR is constant over the entire coverage area and does not decay with increasing distance.

To gain insight in the present NVIS propagation, measurements from the nearest ionosonde may be used. Observing the diurnal variation of the critical frequency of the F2-layer for the ordinary wave (foF2) and extraordinary wave (fxF2 or fxI) over one or two sidereal days will give an indication of the propagation to be expected in the next few days. Johnson [47] compares measured 24 h NVIS link availability with VOACAP [48] simulations on several frequencies between 3 and 9 MHz during a solar minimum. Walden [49] reports that several propagation prediction models neglect the effect of the extraordinary wave. In [50] basic recommendations and formula for ionospheric propagation prediction are provided, and in [51] a state-of-the-art ionospheric prediction model is described. Combination of ionospheric parameters measured in real time with ray-tracing software using the International Reference Ionosphere (IRI) model [52, 53] makes improved short-term propagation predictions possible.

For many years, the model of Watterson et al. [96], also described in ITU-R Rec. F.1487 [97], has been the standard ionospheric channel model for analysis and performance evaluation of HF communication systems. While this model properly simulates the signal perturbations such as signal fading, Doppler and delay spread occurring in an interval of a few seconds, it does not represent the variations of the channel quality, especially the SNR, occurring in longer intervals in the range of a few seconds to 10 min. In [98], both long-haul and NVIS measurements are performed to model the SNR variations to improve the Watterson model. Some work can be found on the study and modelling of the channel characteristics using polarization diversity techniques to improve system performance [56]. Finally, measurements on broadcast signals in the medium wave (MW) band are used to improve the accuracy of the channel predictions for network planning in that band [84, 99], providing the first channel model for NVIS in the medium wave band [100]; a tap delayed line (TDL) model based upon the field measurements.

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"Change Active Hours" (Win10) In Windows 10, go to "Windows Update" and change your "Active Hours" to reflect your time on the radio to prevent a windows update during the time your using PowerSDR. Privacy Settings (Win10) UnderWindows 10 you will want to turn all the new privacy settings and "how updates are delivered" to OFF (block) . Otherwise your computer will be allowed to constantly send data not only back to Microsoft & others, but allows others to use your computer as an "Update server". Microsoft "Store" (Win10) Open Windows STORE app. In the upper right corner ... click and select setup. Turn off automatic updates of Apps,otherwise Windows 10 will be constantly downloading and installing apps while PowerSDR is running. Microsoft monitoring (Win10) Turn OFF "Microsoft Compatibility Telemetry" (huge drive and cpu usage hog that can start running in the background at any time while running PowerSDR) (text procedure to disable it here) Turn OFF the following Windows "Task Scheduler" items: ---- Microsoft Compatibility Telemetry (huge drive and cpu usage hog) ---- Customer Experience Improvement ---- Power Efficiency Diagnostics ---- Windows Defender (start hard drive scans manually yourself when you want ) ---- Media Center (Since it Windows 10 no longer allows the program to run) Turn OFF the following Windows "Services": All the "Diagnostics ..." services including: policy, service, system, Tracking (assuming all your components are working) Lfsvc: Geolocation service windows 10 Fax: fax Homegrouplistener: Homegroup HomeGroup continuously scans your network for files, printer, devices, data Homegroupprovider: Homegroup Media Center: continuously scans your network. WMPNetworkSvc: Windows Media sharing Windows Search (indexing) continuously updates its index files every single time a file is created, which keeps the CPU(s) & Memory & HDD busy. Turn OFF network Printer SERVICE: HP and others have poorly written network printer Services that will continuously eat up CPU & Network. Turn OFF MSCONFIG STARTUP programs that check themselves for updates (i.e. java, adobe, apple. do the update checks yourself). You can use free CCLEANER.exe to find them and disable them. Schedule your Virus Checker program to update itself & scan at off hours. Dont run the virus scanner when you are using the PC. Many Virus scanner program do background optimization without your knowledge. Usually the only way to quiet them down is to put them into Gamer Mode or Silent Mode. Disable Windows automatic updates. Do the checks yourself. Leave your computer ON, set for HDD & monitor to turn off after 20min of no use. This way the OS doesnt spend time after start-up to do housekeeping. Some Video card drivers(i.e. Nvidia) include Gamer previews that download and update without your knowledge. You will want to make sure you check the "Task Manager" to see any programs that are running and delete them. If you have an NVidia card you will want to check this link to turn off the Nvidia PowerMiser feature: here Run "Task Manager" (right click on the task bar and select "Start Task Manager" then click on the "Show processes from all users". This will show all the hidden processes that require ADMIN privileges to stop. Check them to see if any sneaky programs are running. IF YOUR VIDEO CARD IS POOR: Go to System Properties-> Advanced ->Performance Settings-> Visual Effects->Adjust for best performance (to turn off the graphics extras that you probably dont need)

04/02/16 S6: Add: Special Panafall mode for Sun/GrayLine, 80% Pan, 20% Water only for RX1 (best of both worlds). Fix: Sun/GrayLineOn its own Thread so DX spotting does not need to be on. Fix: Recall color and alpha on startup for GrayLine. Add: Grid lines turn off in Sun/Grayline mode, and turn back on when off Fix: reduce thread cpu time. Gray Line shows what is technically knows as Sunset (lighter area when the sun angle is greater than 90) and Civil Dusk (dark area when sun angle is greater than 96) 04/01/16 S5: Rework SUN/GRAYLINE code so it redraws into the background image instead of the display. This eliminates the CPU time wasting caused by adding items to the display code. The nice side effect is that everything drawn into the display automatically draws over the top of the GrayLine. Also doubled the resolution of the Gray Line for a better image. ADD: GrayLine color and Alpha can be selected (right click on Center button). New : SWL.csv file update from YouTube Video Describing RevS5 : 03/31/16 S4: Add: Gray Line option in the DX spotter (in addition to the Sun Track option). Add: SFI and A-Index next to Sun (from daily NOAA space weather report) Embedded an Equirectangular Projection map that automatically overrides your current image, when either Sun or Gray Line is enabled with DX spotting ON. You probably want to run this with Grid Lines Off. Again thanks to Dick W3WVG and Roland Leigh. Fix: Darkened the night area more 03/29/16 S3: Add: Sun Tracker when using the "KE9NS6_World skin" (download from this page below) and only when the DX Spotter is ON. World skin I Photoshopped is a Robinson Projection that I darkened to allow for easier viewing of the Panadapter, however I scrunched it (vertically) to properly fit the Panadapter proportions. Lat and Long lines are all 15 spaced. The Sun image is embeded in PowerSDR and should track Lat based on the Day of the year and Long based on UTC (Right side is 2359 UTC , Left side is 0 UTC, Center is 1200 UTC). I will try to add Grayline. Work in Progress. If you resize PowerSDR window, it could take up to a minute before it does its next update and moves to the correct position on the map. I may need to change the map projection to make grayline easier. Received some Grayline help from Dick W3WVG and Roland Leigh Fix: try to fix catching QSX or QRX splits 03/27/16 S2: Add: Adjustable TNF notch width (right click on TNF). Was 100hz. Now you can set up to 600hz. Instead of creating multiple TNFs to cover up a noise. Also, Factory Resets for NR and ANF settings. YouTube Video Describing RevS1 :


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