220MHz Repeater Project – Transceiver Modification
This week I started work on the 220MHz Repeater. I’ll be using a pair of TYT TH-9000D 220MHz transceivers and an Arcom RC210 controller. The first step in this project was adding a DE-9 serial port to each of the radios. Luckily this was very easy because not only is there already a DE-9 cutout on the rear of the radio but there’s also a 6-pin header inside the radio that provides all of the required signals. Here’s the pinout of the on-board header with Pin 1 being closest to the front of the radio:
Pin 1: Ground —–> DE-9 Pin 1
Pin 2: TX Audio —–> DE-9 Pin 2
Pin 3: COS —–> DE-9 Pin 3
Pin 4: RX Audio —–> DE-9 Pin 4
Pin 5: PTT —–> DE-9 Pin 5
Pin 6: +5VDC —–> DE-9 Pin 9
I ordered the 6-pin header cables from Digikey [part] but they weren’t an exact fit. I did have to modify the header slightly for the cable to fit. I added a bit of hot glue to the header to make sure it doesn’t become disconnected by accident. The +5VDC out from each radio is not needed for the repeater wiring and will only be used in connection with an Arduino monitoring system that will be wired into the controller and a UHF radio for telemetry. This will be used to verify that the radios are on and or have power.
Showing finished DB-9 connection to internal header.
Since the header cable assembly I ordered from Digikey wasn’t a perfect fit I added a small amount of Hot Glue to ensure the connection doesn’t come loose.
Is there more to this article? How did the two radios pin out to connect to the RC-210? I am thinking this might make a good short-term back up set in the event either my VHF or UHF machines fail.
There is more coming however the project was postponed due to more pressing issues. Once I pickup the antennas and mast where I can start testing I’ll have a lot more info coming.
The radios connect to one port on the RC-210, so it’s essentially a “Y” cable with two DB9 connections for each radio and then one to the controller. You could use one radio per port however that isn’t needed and would just use up a port that could be used for another repeater, linking radio, etc.
Did you ever finish this? We are looking at doing the same thing here in New Orleans.
Unfortunately no, it’s still on the shelf in the same state. Hoping to get back to it at some point.
Hi Brad, Hope you are doing well. Did you test post connecting the DB9 on the radio with ARCOM RC210? That the radios were acting as repeater on single port i.e. Did it work as RX from one radio to TX to another and COS/COR etc. working all ok?
73
Karan, VU2YEP
Hello Karan, unfortunately that project was never completed due to not being able to locate a duplexer or tower site. The radios have since been repurposed.