| Band | Dial freq (MHz) | Tx freq (MHz) |
| 160m | 1.836600 | 1.838000 - 1.838200 |
| 80m | 3.592600 | 3.594000 - 3.594200 |
| 60m | 5.287200 | 5.288600 - 5.288800 |
| 40m | 7.038600 | 7.040000 - 7.040200 |
| 30m | 10.138700 | 10.140100 - 10.140300 |
| 20m | 14.095600 | 14.097000 - 14.097200 |
| 17m | 18.104600 | 18.106000 - 18.106200 |
| 15m | 21.094600 | 21.096000 - 21.096200 |
| 12m | 24.924600 | 24.926000 - 24.926200 |
| 10m | 28.124600 | 28.126000 - 28.126200 |
| 6m | 50.293000 | 50.294400 - 50.294600 |
| 2m | 144.488500 | 144.489900 - 144.490100 |
My Zachtek WSPR transmitter is playing up after years of reliable service.
It is a Desktop unit, ProdNo: 1012, H/W version 2.6, Firmware version 2.04
Initially it was losing the GPSDO and transmitted approx 4 seconds late.
I replaced the GPS and dT improved to approx .5 seconds.
I put the original GPS back and it Locked and dT remained under .6 seconds.
Maybe the MCU clock has not had enough time to drift, but I do get a GPS lock.
I connected a USB cable and ran VK7JJ's web interface, https://wspr.rocks/zachtek/
on linux and it ran for a few minutes and locked up, frozen.
I could disconnect and reconnect the serial and it would function for and short while and the lockup once again.
I connected it with the Zachtek app Version 1, Releasre 18 on MS Windows 10 and had the same issues.
Runs for a while and stalls with the same yellow status on solid and the TX LED off.
I have tried a number of serial emulators (putty, Arduino Monitor, minicom, tio, screen) and set them
to non blocking and they usually give a few lines of output from the Zachtek unit then then lock.
I also tried a few python scripts with non blocking IO.
If I do not attempt to connect the API Apps it appears to run for 30 min, sometimes an hour or more.
It is hard to diagnose as I cannot Set and Get or see much of the log.
I could try updating the firmware, but with the intermittent IO I probably couldn't do it but I have not tried.
Also, it may brick the unit.