Priyom releases Rivet Build 91

02 April 2024

The Priyom team has been working on a new version of Ian Wraith's Rivet decoder for these past months. You probably have used this decoder in the past when decoding modes such as XPA, XPA2 or F06, among others. Today, we are proud to announce that Build 91 has been released!

So what does this new version contain? Keep reading to find out!

F06a decoding

The main change of this update comes with F06 (named FSK200/1000 in Rivet). Due to the increase in F06a usage over the past years, and now running on its own dedicated schedules, the F06a decoder has been split from the existing F06 decoder and is now a selectable mode in the GUI.

F06a bin

As you can see, by default, Rivet will decode the different blocks of a transmission as hexadecimal values instead of the usual digits when using F06a. Keep in mind that F06a carries files, which sometimes are ASCII-encoded and sometimes are just unidentified binary. Rivet b91 provides decoding for both file formats (using binary by default), which can be switched under Options > F06a ASCII parsing.


When using ASCII encoding, Rivet will also print non-printable characters (except CR, LF and EOF) in their hexadecimal values (characters that appear as [0x..]). Line feeds, carrier returns and end-of-file NUL bytes appear as <CR>,<LF> and <EOF> respectively. Apart from this, Rivet will also display the ASCII-encoded filename, big-endian file size and the CRC of the file contents automatically when it detects a header block.

You don't know if what you're decoding is F06 or F06a? No worries! Start decoding as FSK200/1000. Rivet will detect F06a automatically and jump into F06a decoding. And also, if you try to decode a raw binary F06a using ASCII, Rivet will automatically change to binary decoding.


An easy way of identifying the encoding of a file is by reading the filename: Filenames ending with .TLG or .TXT usually feature ASCII encoding, while filenames with no extension beginning with 444 or 044 use raw binary.

Other changes in build 91

  • XPA/XPA2 now prints 10 groups per line instead of 15
  • FSK200/500 and Baudot now use a monospace font
  • Updated Gradle wrapper to 7.5
  • Added and updated some links
  • Minor fixes in FSK200/500


To obtain the new version, you can download the already compiled jar from Priyom's Github page, or get it from here. Or you can also compile it from the source code published on Github.

Here you can also find the checksums for the compiled JAR to make sure you're downloading the right thing and not some random executable:

MD5: A701F9F73A8701E2634A6CF147879D15
SHA256: 67B879076D5B4DACA00664FE9EFC59EFE32C033C0B4C9775DFF15CF74E7AC35E
SHA1: 3E0C8E22FA997CDD00CF57A0DDC5706EC4749608

<EOF> | CRC OK. qsr711