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Radiola 18 Amplifier & PS
#9

A belated thank you for the many useful suggestions.

I have returned to this project after a few medical distractions, and have started soldering the connections. I teach at a small engineering college, Maine Maritime Academy, and after describing this project we concluded students in the campus Radio Club may find it interesting. Consequently I'm back at it. I will greatly appreciate any additional assistance regarding the following.

I suspect using the single 5V filament supply on the new power transformer on both the UX-171-A and UX-80 may not work well as it is also part of the output circuit. This is an uneducated guess on my part as I don't understand tge circuit well, but suspect 2 5V power transformer outputs were used on the original transformer to separate the UX-171-A filament circuit from the UX-280 filament circuit. I have a 5V 10A DC power supply that I think might be a good substitute.

I am also not certain about the audio section interstage transformer connections. The P-T156 transformer has blue and red wires on one side which I assume are the input. These should connect to the UX-226 plate and the #7 connector on the terminal strip. The 2 green and single black wires from the other side have me puzzled. I know black is the center tap, but where are the 2 green wires to be connected?

I've attached photos of the top and bottom chasis plate.        

Thank you, tna


Messages In This Thread
Radiola 18 Amplifier & PS - by TN Allen - 12-11-2022, 12:09 PM
RE: Radiola 18 Amplifier & PS - by Arran - 12-15-2022, 01:14 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 12-15-2022, 10:24 AM
RE: Radiola 18 Amplifier & PS - by Radioroslyn - 12-15-2022, 12:20 PM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 12-19-2022, 06:45 PM
RE: Radiola 18 Amplifier & PS - by TN Allen - 12-21-2022, 10:12 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 12-21-2022, 10:38 AM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 12-22-2022, 05:26 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-12-2024, 11:07 AM
RE: Radiola 18 Amplifier & PS - by Chas - 10-12-2024, 02:18 PM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 10-12-2024, 03:05 PM
RE: Radiola 18 Amplifier & PS - by Chas - 10-12-2024, 08:57 PM
RE: Radiola 18 Amplifier & PS - by Arran - 10-13-2024, 03:15 PM
RE: Radiola 18 Amplifier & PS - by morzh - 10-13-2024, 08:48 PM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 10-13-2024, 09:07 PM
RE: Radiola 18 Amplifier & PS - by Radioroslyn - 10-13-2024, 10:45 PM
RE: Radiola 18 Amplifier & PS - by morzh - 10-13-2024, 11:03 PM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-19-2024, 10:42 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-19-2024, 11:24 AM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 10-19-2024, 08:33 PM
RE: Radiola 18 Amplifier & PS - by Chas - 10-20-2024, 07:15 PM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-21-2024, 10:42 AM
RE: Radiola 18 Amplifier & PS - by Chas - 10-21-2024, 11:18 AM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 10-22-2024, 09:52 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-23-2024, 09:58 AM
RE: Radiola 18 Amplifier & PS - by Chas - 10-23-2024, 10:15 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-25-2024, 06:56 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-25-2024, 04:57 PM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-26-2024, 08:07 AM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-26-2024, 05:58 PM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 10-26-2024, 07:24 PM
RE: Radiola 18 Amplifier & PS - by Chas - 10-26-2024, 08:07 PM
RE: Radiola 18 Amplifier & PS - by TN Allen - 10-27-2024, 05:48 PM
RE: Radiola 18 Amplifier & PS - by MrFixr55 - 11-30-2024, 10:32 AM



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