What is Reddit's opinion of Ultra Compact RS232 to TTL Converter with Male DB9 (3.3V to 5V)?

From 3.5 billion Reddit comments

Yes, you will need a level shifter (3.3v to 5v serial). Google "max3223". Just getting the chip and soldering it up yourself using the datasheet is the cheapest way. If you want a more instant solution, here is one on Amazon that is already on a board with a 9-pin serial connector on one side and holes for pin headers on the other side. Plenty of options out there. Just don't hook the UART on the Pi directly up to the UART on the Arduino. It most likely won't work, and has a good chance to damage the Pi.

Interesting! I was under the assumption I just supplied 5v to power up the GPS and then connected everything else straight to the GPS port on the radio.

https://www.amazon.com/Ultra-Compact-RS232-Converter-Male/dp/B00OPU2QJ4/ref=sr_1_3?ie=UTF8&qid=1505520896&sr=8-3&keywords=Rs232+ttl

I've got one of these or one similar on hand from another project. Is this what I would use to make this work?

If so would the GPS connect to the solder points on the converter and then wire the radio to the DB9?

What do you mean by an RS232 adapter? I have an RS232 to TTL adapter would that work? I just want to be able to read the data sent to the arduino from the RFID reader.

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https://www.amazon.com/gp/product/B00OPU2QJ4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Would this work?

Ultra Compact RS232 to TTL Converter with Male DB9 (3V to 5.5V) https://www.amazon.com/dp/B00OPU2QJ4/ref=cm_sw_r_cp_awd_Q1Nfxb90ZYGRJ