Please be more specific. Do you mean the antenna trace at the top of the PCB as in: https://en.m.wikipedia.org/wiki/File:ESP-01.jpg

Yes like the diagram.and like this one https://www.ebay.com/itm/Esp-12E-ESP8266-Serial-Port-WIFI-Transceiver-Wireless-Module-AP-STA/381374534484?epid=1279738338&hash=item58cbb19354:g:gOgAAOSweW5VY887

### You need to be aware that Bluetooth and WiFi modules are subject to formal, regulatory approvals to ensure that they do not cause radio interference. **Schematics are often not released to avoid circuits and modules being built - even just for personal use - that would not meet the regulatory requirements.** **If they are reported either through causing interference or by anyone who notices that they are unapproved, the use of such unapproved modules can lead to prosecution.** #### The serpentine trace is the antenna. This may or may not work effectively if you do not know the exact dimensions and PCB materials and stackup that was used for the original module. At worst the mismatch caused by an incorrect antenna to power amplifier (PA) match may cause the PA to overheat and destroy itself and the chip it is part of. The `Half-cut` or `Castellated` pads on the edge of the PCB can be created in EasyEDA. See the PCB Order page: https://easyeda.com/order https://easyeda.com/Doc/Tutorial/PCBOrderFAQ#Half-cut-Castellated-Holes ![enter image description here][1] [1]: /editor/20171103/59fc6fc16d969.png