Whip Spring Project for the ATAS-120/120a
The Reason for this mod is shown above. An additional benefit is that the spring will also help seal out water, which, even with the newer "a" model, can get into the antenna through the opening for the whip in the boot. If you make this mod, I would be interested in hearing from you as to how you like it.
1. Photos of the Yaesu whip and Antennex whip cut to the same length and flexed back tip to tip showing the return to norm. Please note the bend in the Yaesu whip. That bend occurred while driving 70mph on the highway and it would not return to its original shape. It is due to the very soft grade of stainless steel used by Yaesu. I used an Antennex whip because I had already one. Antenna Specialist will also work equally well.
2. To disassemble the coil. Remove the rain cap and the two set screws
3. Then slide the outer weather cover off the top of the coil
4. The Antenna Specialists spring assembly with hardware from my junk box. This spring is available from Antenna Specialists dealers as the K-126 replacement spring. I had several in my junk box.
5. Enlarging the hole. When drilling out the center of the whip holder, be sure to secure the upper coil section to prevent rotary flex by the drill. Use a #7 drill bit. This is the recommended size bit for the 1/4x20 thread. A tap/bit combination can be purchased at Home Depot for about $6.00. Be careful when drilling not to go too deep. I went only to below the set screw openings.
6. After drilling the hole, carefully tap the hole with a 1/4 x 20 SAE thread. I would personally recommend cutting only three or four threads at a time the backing out several turns to help clear the hole before cutting more threads.
7. Install the stud 1/4 x 20 stud into the antenna coil before replacing the coil outer cover and weather boot.
8. Slide the cover to the coil top section over the coil, install the set screws, and cut the nipple off the rubber rain boot
