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Fsq fldigi software#
Fsq fldigi tv#

This SSTV image was transmitted from Spain and received in Wisconsin on 14.230 MHz.

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Upload one or more images, most likely degraded, for a quality percentage comparison to the original. Upload 'original' image to be used as the standard of comparison. Fuzz may be expressed in absolute intensity units, or as we will do for SSTV imageĬomparisons, expressed as a percentage of maximum possible intensity value of each pixel.įrom experimentation, 10% might be a useful fuzz tolerance level for expressing the quality of a received image. Colors within this distance are considered equal. Fuzz is used to match colors which are close to the targetĬolors in RGB space. A 'fuzz' adjustment is available in ImageMagick. In practice there is significant deteriation. This may be viewed as a measure of picture quality received. Of matches to the total is expressed as a percentage. This is a total of 81,920 pixels in many SSTV pictures.

Fsq fldigi software#

ImageMagick is powerful software package that can compare two images pixel-by-pixel, e.g., a 320x256 pixel JPG image from an SSTV transmission. Considerable image degradation occurs as soon as the software, eg, MMSSTV, readies the image for transmission and losses are magnifiedĪs the signal encounters path loss when it moves through the ionosphere. If a ham received an image perfectly, there would be a 100% match. Image displayed on an SSTV cam in JPG format.

Fsq fldigi tv#

Listen for me on 7104 kHz.The quality of a received Slow Scan TV (SSTV) picture may be determined by comparing, pixel-by-pixel, for identical matches in RGB color space for the customary If you already have a digital modes interface for your computer, give it a try. Peter went from just hearing about the mode to his first QSO in minutes! He was my first FSQ QSO as well. While playing around with the FLDIGI program, which now supports FSQ, I saw the callsign ve3so pop up on my screen. I mentioned the article in the September QST.Īfter signing with Peter, I tuned up to 7104 kHz, the FSQ frequency on 40m. Peter said that he hadn’t heard about FSQ before, but it sounded interesting. During our QSO, I mentioned that I was going to try out FSQ later that evening. I called CQ on 7026 kHz and got a call from Peter, VE3SO. My first FSQ actually started out as a CW QSO. I did, however, make my first FSQ QSOs on 40m last night. I was hoping that Thom and I would have had this all working on 2m by now, but circumstances have gotten in the way. Depending on what you have in your junkbox, this circuit should cost you about ten bucks. So, as we also want to experiment with cheap sound cards other than the Signalink ( like this Syba sound card), we’re also building the ZL1BPU VOX PTT circuit (see below). One thing we found is that the VHF transceivers that we both have do not have VOX capability. Thom, W8TAM, and I are going to experiment a little with this mode of operation. There’s also a relay feature that you could use to send messages to stations that perhaps cannot reach the repeater, but could reach a station not on the repeater.

I would use this network to send messages and images, maybe schematics, to those stations when I had something to send them. I envision a “network” of stations here in Ann Arbor who are all running FSQ, monitoring the local repeater. That third feature would seem to be especially useful for use on VHF. You simply type in a line, hit RETURN, and the software sends your callsign and the line you just typed.

It’s a lot like chatting over the Internet.

It has several features that really appeal to me: I forget how I got interested in FSQ, but I probably heard about it sometime late August, and then there was an article about it in the September 2015 QST. The FSQ modulation, coding and FSQCall protocol are publicly disclosed and described, and the software is open source. FSQ transmission is also well within the capability of micro-controller based devices for low-power propagation transmissions (MEPT and telemetry). It can also be used on VHF FM, and clearly has a much wider useful range of operating conditions that other more conventional digital modes. It works well under NVIS and sunrise/sunset conditions on the lower bands, and also works well for short skip and grey-line on higher bands. What is FSQ? Well, ZL2AFP, one of the developers, describes it this way:įSQ is a Fast Simple QSO mode designed specifically for HF. Last night, though, I made my first FSQ QSO. I’m an occasional user of digital modes, mostly PSK-31.