eWWVB ES100 6-pin connector

Use official 2.5 mm JST connector, or a 6-wire 0.1" (2.54 mm) ribbon cable M/F jumper works too:

6 = EN
5 = SDA
4 = SCK
3 = IRQ
2 = VDD
1 = GND

https://universal-solder.ca/product/everset-es100-cob-wwvb-60khz-bpsk-receiver-kit-with-2-antennas