Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM

[-]
Who's Online
There are currently 2610 online users. [Complete List]
» 2 Member(s) | 2608 Guest(s)
AvatarAvatar

>