Welcome to the WCARES Weekly Winlink Net! Week 2
Quick Start:
Exercise Task: 1. Send a WLE msg via a PACKET RMS station.
Challenge Task: 2. Investigate the furthest Packet RMS station you can reach.
*** If you cannot send messages by Packet, read the lesson and check in by another method (even Telnet).
2, KD7ISA, Telnet, N/A, 0.000, Hillsboro, Washington, Oregon
Background Information:
Last week, you were asked to send a simple, plain-text check-in message using the VARA FM mode.
Under what conditions should you consider using the Packet Mode? Thanks to Andrew, N1ACW, for the following discussion:
There are times when sending a short message to a packet RMS is significantly faster than using VARA FM. Why!? Transport protocols take time to negotiate what the optimum link looks like. I won’t go into the gory technical details, but you’ve all seen VARA FM go through this cycle. It can take a while. The reason is that as messages get short, this negotiation time becomes a significant part of the overall message sending time. Packet is much, much faster at figuring out how the connection should proceed.
Here are some heuristics from my experimentation: Packet will probably be faster when the message is < 1 kbyte, your proximity to a packet station is < 10 – 15 km (roughly six to ten miles) and you have pretty much a direct line of sight. These conditions are important. Packet does not use forward error correction. If a packet is received and deemed broken, the recipient will request a resend (NAK). Vara FM uses forward error correction so it can fix some breakages without sending a NAK.
There are other benefits of having the packet option open to you. A VARA FM RMS may not be in reach but a packet RMS is. You don’t have to wander far from the metro area where this is the case. When the VARA FM channels are all busy, then sending a short message by packet can keep you productive.
This week’s exercise: Using any RMS of your choosing, use the Packet mode to send your identification string to the tactical call sign: WCARES-NCS.
Open the Message tab.
Select New Message.
Address your message to: WCARES-NCS
Identify the Subject of your message as, “WCARES Weekly Winlink Net __,” indicating the current Winlink Net number. It is #2
In your message body, insert your check-in sentence with all components on ONE LINE. Separate each piece of information with a comma. Here is the information requested:
Week number, Your call sign, the Winlink Express Mode employed (Packet this week), the call sign of the RMS station used to send the message (use N/A if you respond via Telnet), the frequency of the RMS station used (use 0.000 if you respond via Telnet), City, County, State (e.g. Oregon)
Here is an example of validly constructed “check-in sentences”:
2, KD7ISA, Packet, WC7EOC-10, 144.980, Beaverton, Washington, Oregon
2, KD7ISA, Telnet, N/A, 0.000, Hillsboro, Washington, Oregon
Post your message to the Outbox.
Open a Packet Winlink Session.
Use the Channel Selection tab to open the Packet Channel Selector menu. Use the Update Table via Internet tab to refresh the Packet RMS station list.
Choose a Packet RMS station by double clicking on the line identifying that station.
Close the Channel Selection window.
Set the Packet Radio Frequency on your transceiver.
Test your connection to your chosen RMS station by Starting a Packet Session.
Optional Challenge:
Investigate how far from your station you can successfully engage a Packet RMS station. Attempt to open a session with an RMS station at least 30 miles away and work your way up through the list of Packet RMS stations until encountering a station that you can successfully engage.
Have fun testing the limits of your equipment!
Thanks to the creators of this content, Lake Oswego ARES of Clackamas County ARES.
