Thursday, May 28, 2020

Internet Over Winlink

Trimmed SlashdotOrg
What, Internet via radio!? Well, sort of. In this article I will discuss how you can get useful information from the web even if you are nowhere near an internet connection.

I've written about the Winlink service in the past, so if you have no clue as to what that is, you might want to follow this link and check that out first. Or, head over to Winlink.org. Basically Winlink is a way of sending email via radio, but it turns out you can do a few more useful things with it. 
Winlink Catalog
Winlink Catalog

If you are using Winlink Express, you have the ability to post requests from the Winlink Catalog. This is found under "Settings" and "Winlink Catalog Request." From the dialog that loads, you can see lots of useful information you can request, most of which is weather related. But what if you want something not listed in the directory? Maybe you want to see the top stories from Slashdot.org. You are in luck! 

Through a service called SailDocs you can request almost anything from the web you might need. If you read up on the history of Winlink, you will learn that it is also used by mariners as a commercial service called SailMail. It's a handy way people aboard ships at sea can email back and forth anywhere abroad. SailDocs is used along with SailMail (Winlink) to obtain webpages or files from the Internet in a format that's easier on bandwidth. 
SailDoc Query

To use SailDocs you simply send them an email via Winlink with a send command in the body of the message. To get that copy of the Slashdot.org homepage, you would simply send an email to query@saildocs.com with "send https://www.slashdot.org" in the body. Once the message is sent, it takes a few minutes for their server to grab the site, trim all the fat, and send it to you as a clear text email. 
Trimmed SlashdotOrg
Trimmed Version of SlashDot.org

The service works quite well, but you need to be a bit careful with it. The messages can still be quite large as far as email over HF is concerned. (Slashdot.org homepage was 11.361KB when I downloaded it.) Before utilizing it in the field, I would suggest trying it via a telnet session over the internet first to ensure the result works for you and the file size isn't too large. I tried a few webpages where the trimmed up version I received wasn't very useful and was way too large to be sent over radio. 

WX Radar Image
WX Radar Image via SailDocs


That being said, I've found it works well with various news sites and National Weather Service web pages. In fact, if you visit nws.noaa.gov and lookup the weather for the area you are interested in ahead of time and make note of the url in your browser, you can post a send request for it while out in the field and have an up-to-date detailed forecast for your precise area. Much more detail than the file you obtain via the Winlink Catalog Request. You can also receive files, such as images, the same way. But again, they are much larger than simple text files and you shouldn't hog all the Winlink resources just so you can get that latest meme.(Latest radar image from NOAA, about 60K.)

For real world use, I would suggest making yourself a list of URL's you would like to access ahead of time. You can't exactly browse the internet, but if you need close to real-time information, this is a handy tool. Again please use the service responsibly, radio spectrum is a shared resource. If you find your file is taking too long to pull in, don’t be afraid to hit that quit button.


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