Yaesu G-5500 AZ-EL Rotator manual (schematic LAST PAGE) http://www.radiomanual.info/schemi/ACC_rotator/Yaesu_G-5500_user.pdf Look at the Yaesu G-5500 Schematic diagram, to start your Troubleshooting. Parts readily available from Yaesu USA or Electronics Distributors (Digi-Key, Mouser).
UNPLUG Rotator Controller from AC Line Voltage, before Opening Case. Have your bench DVM/VOM for testing Diodes within unit.
1. Failure [open] of the Toshiba 1S5188 diodes (D14, D16, D18, D20, D21) would cause remote control failures -- via DIN 8-pin connector. 2.) The Texas Instruments RC4558, Dual General-Purpose Operational Amplifier, is active component (Q3 and Q4) for Analog Meter operation. May have damaged a section of that IC. == Toshiba was OEM supplier to Yaesu. 1S1588 is a silicon diode, U = 35V, I = 120mA, applications: fast switch
EIC 1S1588 Data-sheet, High Speed Switching Diode, DO-35 Glass Case, ~35 V http://www.eicsemi.com/DataSheet/1S1588.PDF
Texas Instruments RC4558 Product Page http://www.ti.com/product/RC4558 The RC4558 device is a dual general-purpose operational amplifier, with each half electrically similar to the µA741, except that offset null capability is not provided.
Appears you had an ESD event. Lightning strike nearby? http://www.sunsunsun.net/kd4app/amsat/g5500.htm
Replacement G-5500 Controller from Yaesu USA Parts: $300.00 http://www.yaesu.com/?cmd=contactus
greg w9gb === Date: Fri, 8 Sep 2017 19:14:23 +0000 (UTC)
Hello, My Yaesu G-5500 works only manually for Azimuth & Elevation 1.) No meter indication on Elevation. 2.) No computer control using SATPC32 application.
Ideas for troubleshooting ? 73 Bob W7LRD --