MARCONI 2945A POWER SUPPLY MODULE 44991/179 HELP NEEDED - Page 1
Forum section: electronics / general

author: GusCX
author_rank: Newbie
timestamp: December 29, 2020, 04:00:44 pm
content: Dear forum users:I am repairing a Marconi 2945A. Equipment was working up to the Self-test screen until trouble happened at Power Supply module 44991/179.I am used to component-level troubleshooting and Power Supply repairs; however, I have no detailed schematic diagram, just what comes in the Manual: External connections and block diagram.I have the equipment Service Manual but neither the diagram nor the components are listed.Module is defective and I am looking for:A. Schematic diagram.B. A complete working replacement module. (Refurbished is acceptable)C. A qualified service center where I could send the module for repair.Any help is appreciated. Thanks and regards

author: DuPe
author_rank: Regular Contributor
timestamp: December 29, 2020, 04:33:05 pm
content: maybe this post would fit better in the repair forum

author: George Edmonds
author_rank: Frequent Contributor
timestamp: December 29, 2020, 05:30:17 pm
content: Hia) There are no schematics available, the power supply was a third party product of propitiatory design.b) You may find hens teeth easier to find.c) All commercial support for the 2945A has long since ceased.Look on the rear of the 2945A you should have a label mentioning the name Powertron and a version number such as MI/5 or MI/6.The power supply should be dual input voltage, Does it fail to work on either AC or DC input?George

author: GusCX
author_rank: Newbie
timestamp: December 29, 2020, 06:21:44 pm
content: Hi George !Thanks for your reply.He commented:A-The source and the equipment do not have any label on the back that identifies the model of the power source.B- Indeed, it has an option through a cannon connector to feed with 2 DC voltage ranges.The power supply works with AC from 110-220Volts.It may be helpful to know which is the model or version of this power supply.If you need any other additional information I have no problem.Gus.

author: GusCX
author_rank: Newbie
timestamp: December 29, 2020, 06:33:46 pm
content: sorryHe did not answer her question.The power supply does not work with either AC or external DC power. Just turn on the fan and the rest of the output voltages are at zero, testing the source without load, (connector A and B)Quote from: GusCX on December 29, 2020, 06:21:44 pm

author: KD0CAC John
author_rank: Frequent Contributor
timestamp: January 02, 2021, 12:15:15 am
content: so how much , no price ?

author: GusCX
author_rank: Newbie
timestamp: January 02, 2021, 12:38:53 am
content: Hi John, I have sent you a private message...Did you got it?

author: wenzins
author_rank: Newbie
timestamp: September 22, 2021, 02:23:33 pm
content: Hello Gus,Not sure whether this power supply issue was resolved. Do you have this part, or another solution?Wenzins

author: GusCX
author_rank: Newbie
timestamp: September 22, 2021, 04:43:28 pm
content: Hi Wenzins,Thanks for your concern. I managed to repair the power supply and it is working perfectly thanks to the help of a friend.Now I'm on plan B trying to solve other things that are a little more difficult.GreetingsGus