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Table of Contents
JS8 using IC-7300
To get started, have a look at these two pages:
JS8CALL Setup
Under File
→ Settings...
Radio
→CAT Control
:- Rig: Icom IC-7300
- Serial Port: Depends on each computer
- Baud Rate: 9600
- Data Bits: Default
- Stop Bits: Default
- Handshake: Default
Radio
→Rig Options
- PTT Method: RTS
- Port: Same as on the
Cat Control
page - Mode: None
- Split Operation: None
- Tx Delay: 0.2 s
Audio
- Soundcard Input and Output: (USB Audio CODEC)
Computer Timing
JS8Call transmits in blocks of 15 seconds. For two stations to be able to communicate, the start of these blocks has to be synchronized to within about 2 seconds of the horizontal lines on each station's scope. That's why it's really important for everyone to keep their computer clock as accurate as possible (to within 2 seconds of each other). (see http://js8call.com/faq/)
Here's an example of a block that is within the horizontal lines, so it's well synchronized (with my station anyways):
There are three ways to adjust your clock:
- You can use an internet service to adjust your computer's clock such as Network Time. Here are the Network Time settings I changed so that it keeps my clock within 200 ms:
- If you're “offline”, you can use the WWV time signals1) on 2.5 MHz, 5 MHz, 10 MHz, 15 MHz, or 20 MHz.
- You can use the Time Drift tool in JS8CALL, which adjusts the program's clock without changing the operating system's. Make sure that this has a check mark:
View
→Show Time Drift Controls
, then at the bottom of the screen you'll see theTime Drift
tool. Use the up and down arrows to adjust your time drift (more on this below):
Here's how to use the Time Drift Tool:
- If everyone's computers were perfectly synchronized, all these
Time Delta
entries would be 0 ms. Realistically, there's always be a bit of variance, but you should try to ensure that your clock is synchronized with most other operators. - For example, suppose that most operators are around +500 ms, then you'd want to adjust your
Time Drift
to -500 ms to cancel out theTime Delta
(and vice versa). Note the sign (+/-) of theTime Drift
is opposite that of theTime Delta
For example, here I had to put aTime Drift
of -100 on mine to match the other operators: - The last thing to keep in mind is that this time drift might need to be adjusted periodically depending on how well your computer keeps time.
Troubleshooting
CPU Overload
The Issue: Sometimes the QSOs in JS8Call don't get decoded properly: The waterfall shows the data blocks being received, but the text doesn't show, or parts of it do, but with gaps showing as “…” instead.
The Reason: At first, I thought that the YAAC (the APRS program I was running at the same time) was causing the issue because when I close it, JS8Call would start behaving again. But it turns out that it was simply a lack of CPU power. I'm running JS8Call on a cheap mini computer and was reaching 100% CPU when running JS8Call, YAAC, and Firefox at the same time.
Turns out that running any two of these programs is fine, but not all three.
To check on your CPU usage, press CTRL+ALT+DEL on your keyboard, then select Task Manager
.
Note
The first draft of this page was copied over from VA7FI's site with permission. Please feel free to expend on it.