[amsat-bb] elev rotor

[Gregory Beat]

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.
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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
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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 
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