My Experience using Antrac

In 2023 I bought myself a Antrac controller to build, for using with my 3 mtr EME dish

After building the several parts from the controller I tested the principle operation and it looked fine to me.

I had to wait until half 2025 before I got my 3 mtr dish to my new QTH in DL and the project with the Antrac was on hold a bit to background.

When I wanted to continue with preparation of the antenna controller I made a stupid mistake, not realising that the whole controller works on 5V DC.
I am used that everything works on 12 V so when I wanted to test it I did put 12 V on it.

At the moment I connected the 12 V I heard some knispering sound making me realise I did something wrong.
At first I thought I had reversed polarisation but after checking I realised what I did wrong
I Had no idea how to repair and was convinced I blew all components from the controller board.
My expectation was that the board would be far beyond repair.

I decided to order new boards and make a new setup, when it arrived assembling was done without problems and the first light worked out well.

After this I also tested the encoder board with a HH12 encoder which worked fine.

Then it was time to connect the motor steering board and test the whole Antract controller as meant to be. All worked fine.

Then I started mounting the several boards into a watertight box to be mounted close to the Antenna.

I made some mechanical construction parts to hold the main board and when ready I wanted to test.

Now I was well aware that Antrac working on 5V so connecting it and be sure that polarity was also good.

Put on the controller giving me bit more than 1 Ampere current and no light in the display, quickly off.

After checking and trying again, as all connections seemed correct, it still taking 1 Ampere but after 2 seconds the current drops to zero.

I tested the third Antrac working fine and mounted the mechanical support I made on this one,
I became suspicious that the support could be causing the high current as all parts of the support was metal and screwed to the controller board.

Indeed the third board now took also too much current, but now I did set a current limit on my power supply at 0,4 Amp.

After loosening the mechanical support the test went well and Antrac system was working fine in the waterproof box.

Now with two Antrac boards and displays lost, I decided to do some further investigation and try to understand the circuit,
perhaps the last Antrac, which was lost due to too much current, could be fixed.

In the documentation from Antrac it was clear that the 5 Volt was reduced to 3.3 V for the computer chip and the 3.3 V also was used in the display.
I decided to measure the 3.3 V and found that it was not available.

Then I tried to search on the Internet for schematics of the ESP-DEVKIT and found this one.

The schematic showed me that the 3.3 V is made using a AMS1117-3.3 which was easily found on the board.
Measuring the voltages on the board the 5V was present but no 3.3 V giving me the conclusion that the AMS1117-3.3 had blown.

I searched the Internet and found a cheap delivery of 10 pcs AMS1117-3.3 for just below 3 Euro including shipping.
After two days the AMS1117 had arrived and I replaced the broken one by first cutting the 3 connections and then solder the heat sink part.
After cleaning up the board I mounted the new AMS1117 soldering it and clean again.

	The ESP32-DEVKIT board with de-soldered AMS1117-3.3
	The board after cleaning with alcohol
	After mounting the new AMS1117-3.3
After testing this board all worked fine
	I decided to measure the first blown Antrac controller and found that it also did not have 3.3 V out from the AMS1117 I replaced the AMS1117 on this first blown board also, and after that the 3.3 V was present and the board is working fine again Both blown Antrac boards are working now, so I am happy I tried to find a way to repair the units.