Classic Rotary Phones Forum

Telephone Identification, Repair & Restoration => Telephone Troubleshooting and Repair => Topic started by: cloyd on August 16, 2015, 05:43:40 PM

Title: Four-Prong Phone Problem
Post by: cloyd on August 16, 2015, 05:43:40 PM
I just received a DialGizmo the other day which enabled me to test my phones.  Luckily, all the phones I tested worked and dial etc. except the four prong phones.  I used a 4-prong-to-Modular adapter in line with the DialGizmo and I get NOTHING.  The 4-prong phones I tested: Kellogg Redbar, AE35 and an AE40.  I had a second adapter and second DialGizmo that I substituted with the same results.  Nothing.

Are there wiring modifications that need to be made to go from 4-prong to modular?  If so, I will post pictures.

Thank you for your help.

Tina Loyd
Title: Re: Four-Prong Phone Problem
Post by: cloyd on August 18, 2015, 07:26:40 PM
From the shattering silence, I gather that I need to post pictures of specific 4-prong phones to reveal problems.  How unusual that no one has a helpful suggestion!

Pictures coming soon,

Tina
Title: Re: Four-Prong Phone Problem
Post by: G-Man on August 18, 2015, 07:43:19 PM
Quote from: cloyd on August 16, 2015, 05:43:40 PM
I just received a DialGizmo the other day which enabled me to test my phones.  Luckily, all the phones I tested worked and dial etc. except the four prong phones.  I used a 4-prong-to-Modular adapter in line with the DialGizmo and I get NOTHING.  The 4-prong phones I tested: Kellogg Redbar, AE35 and an AE40.  I had a second adapter and second DialGizmo that I substituted with the same results.  Nothing.

Are there wiring modifications that need to be made to go from 4-prong to modular?  If so, I will post pictures.

Thank you for your help.

Tina Loyd


Did you wire the modular cable's red and green wires to their respective "R" and "G" terminals of the four-prong jack?


Title: Re: Four-Prong Phone Problem
Post by: unbeldi on August 18, 2015, 07:43:52 PM
Well, I guess no one really had good information to bite on.

Make sure you understand the pinout of the four-prong plug and jack, the terminals are usually labeled by colors  red, green, black, and yellow.  green and red is what you need. Those are the pins that the farthest apart on the plug.
Make sure the phones that you connect follow the same wiring system.
Title: Re: Four-Prong Phone Problem
Post by: G-Man on August 18, 2015, 08:00:03 PM
Quote from: G-Man on August 18, 2015, 07:43:19 PM
Quote from: cloyd on August 16, 2015, 05:43:40 PM
I just received a DialGizmo the other day which enabled me to test my phones.  Luckily, all the phones I tested worked and dial etc. except the four prong phones.  I used a 4-prong-to-Modular adapter in line with the DialGizmo and I get NOTHING.  The 4-prong phones I tested: Kellogg Redbar, AE35 and an AE40.  I had a second adapter and second DialGizmo that I substituted with the same results.  Nothing.

Are there wiring modifications that need to be made to go from 4-prong to modular?  If so, I will post pictures.

Thank you for your help.

Tina Loyd


Did you wire the modular cable's red and green wires to their respective "R" and "G" terminals of the four-prong jack?




Also, if the modular cable's wires are not color-coded, then the two inside wires are to be connected the "R" and "G" four-prong's terminals.
--------------------"B"
--------------------"R"
--------------------"G"
--------------------"Y"
Title: Re: Four-Prong Phone Problem
Post by: NorthernElectric on August 18, 2015, 08:06:31 PM
Are any of the phones you have tested successfully the same as those that didn't work with 4 prong line cords?  If not, try swapping a known good modular line cord (from one of the other phones if necessary) onto one and see if that works with the gizmo.  If that phone now works, that should pinpoint the problem to the adapter.  I'm assuming that it's unlikely that all of your 4 prong line cords are faulty but I suppose that is possible.  If you have swapped a 4 prong line cord onto a phone that you previously tested successfully, then double check your line cord connections at both ends, test continuity on the line cord, and if no problems are found, then again the problem is likely the adapter.
Title: Re: Four-Prong Phone Problem
Post by: poplar1 on August 18, 2015, 08:34:21 PM
Did you try connecting the 4-prong jack's modular pigtail directly to the line, i.e., leaving out the Dialgizmo. When you do that, do you have dial tone (even though I realize you can't dial out)?
Title: Re: Four-Prong Phone Problem
Post by: G-Man on August 18, 2015, 10:02:44 PM
Quote from: poplar1 on August 18, 2015, 08:34:21 PM
Did you try connecting the 4-prong jack's modular pigtail directly to the line, i.e., leaving out the Dialgizmo. When you do that, do you have dial tone (even though I realize you can't dial out)?
PERFECT!!
Title: Re: Four-Prong Phone Problem
Post by: andre_janew on August 19, 2015, 03:58:52 PM
Also check for shorted wiring and loose connections.
Title: Re: Four-Prong Phone Problem
Post by: cloyd on August 19, 2015, 05:29:24 PM
Now THAT is information that I can work with!  Well done gentlemen!  I will try the modular cord trick first.
Thank you!
Tina