George - I bought this 1:1 balun for my AH-4 after talking with the owner. In my case I wanted to use my AH-4 with a ladderline fed dipole but honestly below could work for any AH-4 setup. I have my balun placed between my AH-4 and the antenna wire and ground. As in: Coax & control lines from shack > AH-4 > AH-4 positive to balun positive, ah-4 ground to balun ground > balun positive to wire antenna / balun negative to ground radials/counterpoise if using vertical, or to second half of dipole. Model 1171 - 1:1 ATU Current Balun, 1 - 54 MHz, 5kW Model 1171ts - Studs Input & Output https://www.balundesigns.com/model-1171-1-1-atu-current-balun-1-54-mhz-5kw/ "Actually the best choice would be the model 1171 installed between the ladder line and your tuner. This will transform the feedline to unbalanced for the tuner and keep common mode out which creates a false match. You can use the 1171tx which has studs for the input and output."