Automatic Antenna Tuner 7x7 ATU-100 mini by N7DDC

Automatic antenna tuner for HF transceiver (7 coils and 7 capacitors)
November 2020

Soldered board of ATU (Automatic Antenna Tuner) developed by N7DDC. (firm. version 3.2)

• Power supply range: 10 - 15 VDC
• Max current : 450mA
• Max working power: 100 watts
• Max measured power: 150 watts
• Minimum power for tuning start: 1 watt
  
• Recommended maximum power while tuning not above 30 watts. (after tuning you can set 100 watts and work on this power)
• Minimum measured power: 0.1 watt
• Step for measurement on powers under 10 watts: 0.1 watt
• Step for measurement on powers above 10 watts : 1 watt
• Power measurement accuracy : 10%
• Maximum inductance set: 8.5 uH
• Minimal step for setting inductance: 0.1 uH
• Maximum installed capacity: 1870 pF
• Minimal step for setting capacity: 10 pF
• 100 Watts tuner, 7x7 (7 capacitors x 7 coils) based on PIC 16F1938.

originally setup 2019

Dimentsion - 120 mm x 62 mm.

You will get full assembled PCB.

December 2020

ATU-7X7 by N7DDC

Got this kit on Aliexpress. It came with everything, even a box can be used. Looks like a great project. Let's find out how great it is... If you use LCD 16x2 and have problems with weird characters, you should downgrade the software to the previous version, 2.8 worked for me on mini-board 5x5. Looks like the incompatibility of the LCD screen- Winstar wh1602b-tmi-jt. On OLED LCD it works fine. check other videos where we figure out that.

If you need special functions, you will find all the solutions in the manual online, I like the autotune function. and It looks like I will also have to check it 🙂.
I don't completely trust this tuner, since all caps are from Chinese suppliers, and didn't install them myself from a known supplier.
After a month of use, it has proved it self as reliable product.

testing gear: Yaesu ft450d, fan dipole, output power 50w.

https://github.com/Dfinitski/N7DDC-ATU-100-mini-and-extended-boards#3d-printed-housing-for-091-oled-display-3-buttons-and-tnc-rf-connectors

https://www.tindie.com/products/ra0sms/automatic-antenna-tuner-7x7-atu-100-mini-by-n7ddc/