Yaesu DR-1X repeater installations I’ve been able to look at have mostly had an added Receive Preamp added to help the RX side of the DR-1X better match the TX side.
Dave N9JDZ assembled the Preamp in use at the Washington Island WI9DX 2m repeater, and pointed me in the right direction to assemble one for the 2m repeater I am sponsoring.
Here are the eBay links for the products I used:
amp module – https://www.ebay.com/itm/Ultra-Low-Noise-Amplifier-10-MHz-to-4000-MHz-Gain-20dB-NF-0-65-dB-LNA-/283092038093
case – https://www.ebay.com/itm/85x58x33-Waterproof-Clear-Cover-Electronic-Cable-Project-Box-Enclosure-Case-LWUS-/181938791306
cables (need two) – https://www.ebay.com/itm/UHF-SO239-female-PL259-to-SMA-male-plug-crimp-RG316-cable-jumper-pigtail-12inch-/322734015890
power supply – https://www.ebay.com/itm/5V-2-5A-Micro-USB-AC-Adapter-Wall-Power-Supply-Charger-Cord-for-Raspberry-Pi-3-/142351967825
You can get all of these same items elsewhere on the internet, but I found eBay was lowest shipped cost by a wide margin.
I’m considering using a sealant to seal the holes around the cables and power cord once everything checks out okay. I’m thinking I can avoid some small insect deciding the enclosure is a good place to live that way.
It’s taken much more time to share this assembly than to have actually assembled two units. (I built a spare for myself.)
Again keep it safe – especially WEAR SAFETY GLASSES when using the Dremel tool.