- interactive propagation charts that show the QSO probabilities and signal power (hover the mouse over the table cells to see the values)
- graphical presentation of sunrise and sunset times to help predict low-band openings (hover the mouse over the 'TX' and 'RX' labels on the bottom left of the tables to see the exact sunrise and sunset times in UTC)
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| An example DX propagation chart. |
I have deliberately kept the layout of the results page to a bare minimum to allow the user to copy the charts to word processing, and make them pretty for printing.
To use this service, the user only needs to know his/her Maidenhead grid locator and press the "Run!" button. If you do not know your grid locator, I have created an easier-than-the-easiest map application to help you find your grid locator : www.voacap.com/qth.html . Just zoom into your location on the map, and your coordinates and grid locator are readily visible on the top part of the map.
Furthermore, if you wish to tweak the default antenna selection by band, you can do so, and even save your selections (click "Save setup"), together your grid locator, for later use. Also, swapping the antenna selections between TX and RX is available with one click!
And, as a bonus, the option to set the sporadic E layer (Es) has been made available. Use this if your location could be under the influence of the sporadic E, e.g. during the summer in the Northern hemisphere.
For the predictions, I have assumed that, on 20M to 10M, the DX uses a 3-ele Yagi at 10 meters AGL, and on low-bands a 1/4 vertical over a good ground. On the user's side, a 3-ele Yagi at 20 meters AGL for 20M to 10M, and a 1/4 vertical over a good ground are assumed. The TX power is assumed as per the DXpedition in question.
73 Jari OH6BG
After the Point-to-point prediction, the Coverage Area map, the blog, the Planner, with this DX Chart VOACAP online - and always free - becomes a must for all fans of propagation. Congrats to Jari Perkiömäki, OH6BG/OG6G, and his team who support this new version !
ReplyDeleteAbout VOACAP read : http://www.astrosurf.com/luxorion/qsl-soft-voacap.htm
ANy chance of building charts for the guys currently in A25? I haven't heard them at all as yet, neither LP nor SP.
ReplyDeleteHi Gary, yes the charts have been updated accordingly :)
ReplyDeleteHI Jari!
ReplyDeleteCan you add my next dxpedition 15-27.03.17. S21GM
http://www.lral.lv/s21gm/
73, Yuris/YL2GM/
Absolutely, thanks for the heads-up!
Delete73 Jari OH6BG
S21GM predictions now available at www.voacap.com/dx.html
DeleteHi Jari,
ReplyDeleteCould you add PG400TH predictions as well?
Please have a look at http://www.pa2p.nl/pg400th
Tnx and keep up the good work.
Jan, PA2P
Hi Jan, please contact me directly via email, and let's talk.
ReplyDelete73 Jari OH6BG
Hi! Jari
ReplyDeleteKindly add our coming dxpedition 29/4-1/5/2017 at Satang Besar Island, OC-165. Grid: OJ51BT. Callsign: 9M8RC
de 9W8DEN
Hi Dennis, added today!
ReplyDeleteVery informativ, easy to use and understand. Thanks es 73
ReplyDeleteJari, Any chance to add XV9D to the charts? I will be QRV 40-15 meters between 16 Nov to 01 DEC. QTH is OK40dw.
ReplyDeleteDefinitely, coming up in minutes from now :) Have a good one!! Vi syns, Jari
DeleteGREAT job, Jari! This is so very helpful!
ReplyDeleteAlong the bottom of the resulting chart are three rows: TX, RX, and MP
I cannot find an explanation for what these are intended to represent.
Many thanks.
--Dr. Larry S. Anderson NN5O
President/Founder, Deep Dixie Contest Club (DDCC)
Hi Larry and thank you for your feedback! The TX (transmitter), RX (receiver) and MP (geographical midpoint of the great-circle route between TX and RX) rows give a graphical presentation of sunrise and sunset times during the given month. The white cells refer to day-light hours, and the dark cells refer to hours of darkness. The times have been calculated for the 15th day of the month (“median”, as everything in VOACAP is about statistics, hi!). Also, when determining which color the hour-cell should have, I have observed the VOACAP way of determining the hours: e.g. 07 UTC is in fact the time period from 06:30 UTC to 07:30 UTC, not the period of 07:00 UTC to 08:00 UTC! If you hover the mouse slowly over the “TX”, “RX” and “MP” labels on the bottom left of the table, you will see, in a small pop-up window, the calculated UTC times of sunrise and sunset at the TX, RX and MP coordinates.
DeleteTks very good Predition
ReplyDelete