¿ªÔÆÌåÓýKen, ? ¡°Once you learn how to use it, and how to interpret the info, it can be very useful!¡± ? I checked the link and it is overwhelming. Do you know of a good beginner resource that one could use in conjunction with it to understand the information it is providing and some context into how that information can be pressed into useful service? ? 73 and thanks in advance! Chris, KD6OUB ? From: [email protected] <[email protected]> On Behalf Of Kenneth G. Gordon via groups.io
Sent: Friday, December 6, 2024 7:48 AM To: Rick Muething via groups.io <rickmuething@...>; [email protected] Subject: Re: [VARA-MODEM] VARA HF Disconnects Before Messages Are Sent ? For propagation information, I highly recommend ? Once you learn how to use it, and how to interpret the info, it can be very useful! ? I use it regularly for point-to-point comms. ? Ken W7EKB ? ? ? Sent via the Samsung Galaxy S21 5G, an AT&T 5G smartphone ? ? -------- Original message -------- From: "Rick Muething via groups.io" <rickmuething@...> Date: 12/6/24 07:10 (GMT-08:00) Subject: Re: [VARA-MODEM] VARA HF Disconnects Before Messages Are Sent ? Patricia, Its all antennas, distortion,? and propagation.? Vara (and all protocols for that matter) have mechanisms for measuring the S:N and frame success rate (How many SUCCESSFUL bytes transmitted per minute.? If that number falls below a certain threshold the protocol?killls?the link rather than taking many minutes of airtime up with low probability?of passing a complete message.? What can help?? Several things: 1) Pick a frequency band and distance which have better propagation.? e.g.? Some bands are better at night or day.? Generally longer distances are weak....but not always.? 2) Short messages of course transfer faster ....avoid big attachments. 3) Check and optimise your antenna. Height, SWR etc. 4) Make sure your radio drive is set to optimum.? Too much audio drive can result in distortion (due to ALC)? ?For the 7300 you want the ALC no more than about 1/4 scale.? Almost all protocols work best with minimal distortion and near optimum power settings.? 5) Select stations and bands based on propagation (history and propagation maps)? ?Also make sure the stations are running (e.g 24/7 etc)? ? Good Luck
? On Fri, Dec 6, 2024 at 9:27?AM Patricia Dominguez via <WA4WSZ=[email protected]> wrote:
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