Hi Jeff,

Well I was assuming that it is the older 5500 model which has an AC motor - this has an instruction manual which shows a 6V regulator (top of circuit diagram).

https://www.yaesu.com/downloadFile.cfm?FileID=8814 https://www.yaesu.com/downloadFile.cfm?FileID=8814&FileCatID=155&FileName=G-5500_IM_ENG_E12901004.pdf&FileContentType=application%2Fpdf &FileCatID=155&FileName=G-5500_IM_ENG_E12901004.pdf&FileContentType=application%2Fpdf

Maybe you have the 5500DC model for which they don’t seem to publish the circuit diagram? Although I doubt that they would have changed that part of the circuit

73

Graham G3VZV

From: jeff griffin via AMSAT-BB amsat-bb@amsat.org Sent: Wednesday, June 26, 2024 9:44 PM To: amsat-bb@amsat.org Subject: [AMSAT-BB] Re: Yaesu G-5500 issue

Ok. I removed the LM7812 and put in a LM7806. I now have 6v between pin1 and pin3. I also still have full scale on the meters. I tried all the things that were suggested. including the OHM test between wire on pin1 and wire on pin3 500 ohms , and 250 or so between wop2 to wop3 and wop1. SO it looks like the rotor is ok, it still rotates in AZ and EL. I'm going to leave the 6v VR in as my cable runs are only about 30 feet. What to do next. I have two broken G-5500 control boxes here, the one I'm working on, and one with a bad transformer(it blows fuse when turned on). I also have half a working spare rotor, I forget if the AZ or EL is broke. If I send the box into Yaesu to fix, it will with the shipping probably be at least $200. I called Yaesu and they have new G-5500 control boxes for $380. I'm running out of stuff to try with this issue, and there isn't a lot of info to try and dig in any deeper. If I don't come up with anything I think I'm just going to buy a new control box, either the Yaesu or possibly another Green Heron FT-21azel. I'm going to give this another day, I'm hoping someone has had and fixed the same issue. Thanks for the continued help with this...

73 Jeff kb2m