I'd say there are no advantages to converting to HDMI, and possibly add complexities... since there is one available, I think it would be easier and cheaper just to use the composite adapter.
Since the pin-outs are different between brands, get something like THIS that mentions "TCL" specifically.
i bought 55r646 open box at best buy & it didn’t have a remote either- picked this one up on amazon for around $20-
Weitov RC902N FMR1 Remote Control... https://www.amazon.com/dp/B0B247LR54?ref=ppx_pop_mob_ap_share
Like the power cable? It's just a totally regular 3-prong one like this! https://www.amazon.com/Amazon-Basics-Computer-Monitor-Replacement/dp/B072BYGKZW/ref=sr\_1\_3?crid=2MRGLKGP4MNXK&keywords=3+prong+power+cable&qid=1665832509&qu=eyJxc2MiOiIzLjY4IiwicXNhIjoiMy4zOCIsInFzcCI6IjMuMzYifQ%3D%3D&sprefix=3+p...
You need an active HDMI cable (i.e. optical HDMI) for runs that long. They are thin, but you cant bend them around sharp corners.
Fosmon 2-Slot to Standard Power Cord (5 Feet / 1.5 Meters), ETL Listed 2 Prong Figure 8 Power Cord / PA-14, Dual Pin Non-Polarized Universal Replacement Wall Cable https://www.amazon.ca/dp/B006348FTA/ref=cm_sw_r_cp_api_i_J49AZAB12CTZA41WX5JT
Replace the feet with a higher stand - for instance:
https://www.amazon.com/gp/product/B078MBL6KM/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1
or something similar.
I couldn’t find a Small Bluetooth mic to hang from my keychain that I was confident would work. But I did buy a replacement remote that does work the way the original does. Still hoping a good solution is just around the corner.
RC902N FMR1 Voice Replacement... https://www.amazon.com/dp/B09MSZ66H3?ref=ppx_pop_mob_ap_share
I don't know what models are compatible with this app but I use it:
https://play.google.com/store/apps/details?id=com.roku.remote
I have the 2020 6 series. I am pretty sure the remote that it comes with is wifi. My TV was randomly turning on. I had no idea what was causing it. I pulled the batteries on the remote and everything is fine now. I even put the remote in the basement to be 100%. :)
Is this a 2021 model or 2020? I'm confused as to why 2021 don't seem to be out but yet https://smile.amazon.com/TCL-Dolby-Vision-QLED-Smart/dp/B0885F5GMP/ref=sr_1_3?dchild=1&keywords=tcl+120+refresh&qid=1623498069&s=electronics&sr=1-3
I bought this for my TCL 8-series (Model 75Q825). 2-prong, fit's perfectly in the TV's receptacle, snug but not overly tight... Not sure if the 636 uses the same, but I would think it's likely- but double-checking would be smart.
https://www.amazon.com/gp/product/B00ROX7JBY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Shouldn’t this work?
If you don't have, get a high quality "Certified (important)" HDMI cable. These are the only ones I buy. They do it all and at the same time, backwards compatible with other HDMI versions.
Throw away the cheap Amazon HDMI cable and just get these, its all I use on my 635.
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https://www.amazon.com/gp/product/B07S1CGQ9Z/
Want to mention that there are other ways to clean it, you might have alcohol pads in a first kit, something like this which is 1.12 if you have prime. https://www.amazon.com/First-Aid-Only-12-011-Antiseptic/dp/B00589UYYA/ref=sr_1_1?crid=UR58DYS97P16&dchild=1&keywords=isopropyl+alcohol&qid=1605900517&refinements=p_85%3A2470955011&rnid=2470954011&rps=1&sprefix=isop%2Cap...
TCL TV's used to come with the RCA adapter, but not anymore apparently, so it would be simpler to just grab one of THESE
I got this stand for my 55R635...has been good for past 15 days
Hemudu Universal Table Top TV Stand Base VESA Pedestal Mount for 27 inch to 55 inch TVs with Cable Management and Height Adjustment,Holds up to 125lbs https://smile.amazon.com/dp/B071YYKLW9/ref=cm_sw_r_cp_api_fabc_PM2PFbPDT2P56?_encoding=UTF8&psc=1