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40-155T Add Aux Input Questions
#1

Hello everyone,

Back during the pandemic, I purchased a 40-155T with the intent to restore.  I was in over my head, so I ended up paying a local radio enthusiast to restore it.  I build a little AM xmitter to listen to my music, but it has since died.

I've got a few AA5 restorations under my belt now, and I have added aux input to one of them.  This Philco sounds better than all of them, and I'd like to add an input to this one.  I've read a number of threads about this on this forum, and had a few questions.

Here's the volume area of my schematic:    

Here's the underside of the chassis prior to the enthusiast's restoration:    

So, here are my questions:
  • The restorer noted one of the pushbutton switches was bad.  Is there any way to use That as the switch to stop the radio signal while using the input?  Seems like an elegant solution.
  • If that's not an option, this radio has the aircraft and police band -- is that an option to disconnect that band, and use that as the "switch" ?
  • If those aren't options, where should I put the switch?
  • The aux input I installed on the AA5 wired into the top and the bottom of my volume pot.  This volume pot has an additional leg (see chassis photo).  Anything I need to differently?
  • This youtuber restored a 39-30, and states you don't need a switch on a transformer set?  Is this right? Do I even need a switch at all?
  • [Video: https://youtu.be/DRFx2QOy4MI?t=845]

Thanks for any advice and help!

David


Messages In This Thread
40-155T Add Aux Input Questions - by tgr131 - 03-18-2022, 11:15 AM
RE: 40-155T Add Aux Input Questions - by Mondial - 03-18-2022, 03:28 PM
RE: 40-155T Add Aux Input Questions - by tgr131 - 03-18-2022, 03:36 PM
RE: 40-155T Add Aux Input Questions - by Mondial - 03-18-2022, 03:46 PM
RE: 40-155T Add Aux Input Questions - by tgr131 - 03-18-2022, 05:32 PM
RE: 40-155T Add Aux Input Questions - by MrFixr55 - 03-19-2022, 09:22 AM
RE: 40-155T Add Aux Input Questions - by tgr131 - 03-19-2022, 09:46 AM
RE: 40-155T Add Aux Input Questions - by tgr131 - 03-19-2022, 11:34 AM



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