N3CRT 23 Aug 2020 Yaesu antenna rotor Cool Capacitor Mod Summer 2020 my elevation rotor on my Yaesu G-5500 rotor system stopped moving. I had previously encountered a nearby lightning strike that affected the rotor pointing calibration. I was able to recalibrate the azimuth and elevation rotor. The rotor worked fine for another year and a half without issue. The rotor system was about 15 years old at the time of failure. It had only been installed (in the air) an estimated 6 years for the elevation rotor. I had previously used just the azimuth rotor at my previous QTH. The elevation rotor stopped one day, so I took it apart. I smelled that smell, and took apart the motor to inspect. It had burned lands on the PCB that distributes the motor power inside the motor. It measuring the motor windings, at least 2 of the 4 windings were damamged. The bearing retainer fingers were broken in a few places, and that likely jammed the bearing and stopped the rotor from being able to turn, burning up the motor. 10 Aug 2020, I purchaed a replacement motor "MOTOR U129-13 PD-8601-007-2" p/n S8100643 for $136.22. The last motor they had in stock at the time. Hopefully not a sign of future servicability of the AC version of the G-5500 system. I also purchased 2 "BEARING HOLDER PD-7505-003-1" p/n S8001530, $4.87 each. In research for repairing my elevation rotor, I found some good web pages showing internal cleanup and repair of the rotor. I found PA1IVO's web page most helpful: https://ivok.home.xs4all.nl/pa1ivo/G-5500.html I decided to get the parts for the cool capacitor replacement mod at the bottom of the page. I ordered 1N5406RLG diodes ($0.45 each) and EEU-EE2V101 capacitors ($3.59 each) from Mouser Electronics. In trying to stuff these components into a Radio Shack premade perfboard, I found this too frustrating and took to my maker friends for advice on schmatic to PCB creation. I was guided to give EAGLE CAD a try by my friend Jason Rausch KE4NYV. He has a great series of YouTube videos on designing PCBs with EAGLE. Check out his playlists here: https://www.youtube.com/user/rpcelectronics/playlists Being that I could not find a pre-done info package for a "stand up" axial lead version of the 1N5406RLG, I needed to create my own parts library. Using Jason's playlist on creating a new part library for EAGLE, I quickly had what I needed to build up a schematic and layout the PCB. Using his other tutorials, I was able to work my way through creating the schematic from PA1IVO's web site in EAGLE and created a PCB layout. I printed the board view in 1:1 scale to make sure that it would fit on the mounting bracket. Due to the compact design, only 1 center screw down location is available on my board. I will also be designing and printing a 3D printed adapter to attach my board to the existing capacitor location inside my elevation rotor. On Jason's and others recommendation, I placed an order with Oshpark.com for low cost fabrication of my "Cool Capacitor Mod". My order consisted of: 2 layer board of 2.20 x 1.55 inches Black substrate and clear mask 6 boards for $34.10 PCB size affects cost so I tried to design the PCB as compact as possible, and to best fit in the existing location for capacitor. In this directory: http://n3crt.net/files/yccm/ you will find the following. yaesu_cool_cap_mod.brd - EAGLE board file. I sent this alone to Oshpark. No need to convert to "GERBER" files. yaesu_cool_cap_mod.sch - EAGLE schematic file. yccm_pcb_bot.png - Bottom preview of the board from Oshpark. yccm_pcb_top.png - Top preview of the board from Oshpark. yeasu_cool_cap.lbr - EAGLE library containing the 1N5406RLG and EEU-EE2V101 capacitor. yccm_readme.txt - This file. yccm_3d_printed_spacer.stl - 3d printable spacer model. EAGLE can be downloaded as a part of a no cost "Makers" license for AutoDesk Fusion 360. See https://www.autodesk.com/products/fusion-360/personal and https://www.autodesk.com/products/eagle/free-download for more info.