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Typical 304, 4 Wire Ringer, Wiring Diagram.

Started by Dan/Panther, May 24, 2010, 02:19:27 PM

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Dan/Panther

This is a typical 304, 4 wire ringer, connected to a 5H dial. Other Dials may wire the Same. Check your connection lettering.

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

poplar1

This is a 304 (not a 302), modified for an individual line.
"C'est pas une restauration, c'est une rénovation."--François Martin.

unbeldi

#2
Nothing is as useful for troubleshooting and wiring as a logically drawn circuit diagram. It is worth the (little) time invested to understand the symbols and principles of drawing circuits.

When confronted with a phone that has a non-standard cord, or even internal leads, with different colors than the standard, a novice would likely still be confused by color-coded connection diagrams. In addition, virtually nobody really understands the operation of a telephone, especially one as complex as the 304, from a connection/wiring diagram.

So, here is a circuit diagram that is easy to understand and most of the standard colors are noted.

The Western Electric 304 telephone set is often confused with the 302.  The 304 set is more complex. It can be identified by several internal features:

  • The 304-type set should have a housing marked H3 near the rear line cord exit. This indicates that the housing has a switchhook assembly with three switches (six wires), rather than two (four wires).
  • The induction coil is a 101B type, not the 101A as for the 302. The 101B has a center tap (M) for the primary winding, but is otherwise electrically equivalent.
  • The B2A ringer of the 304 has its windings split in two parts, thus it has 4 wires emerging. When the slate wire and the slate-red ringer wire are connected, the ringer is equivalent to a two-wire B1A ringer of the 302.
  • Finally, the 304 set has a larger terminal connection plate, with four terminals, mounted on the base between the ringer area and the condenser, next to the coil or transformer.
The same features apply to the wall telephone, the 354, only its housing is marked M3, and the diagram is identical.

This diagram shows what most people want to have configured today to make a 304 set work on modern telephone lines.  This is called bridged ringing or individual service with a two-wire line cord.  The GND (ground) terminal does not need to be connected to the line, just red (ring, L1) and green (tip, L2).

The circuit is drawn in the on-hook state, when the handset is in the cradle.  The ringer part of the telephone is separated (to the left) in layout from the audio portion of the set, but the connection points are labeled (L1, L2) on both parts.

Lewes2

Perfect!  Thanks Dan; I used your color diagram to rewire my 304.  I had no dial tone and no ringer.  I had installed a date matched 1941 5H dial.
I unhook all the wiring on the base and simply started over. 

It started right up on first try and purred like a kitten.   These wiring diagrams you all have done are a god-send!

Chuck

N7LTH

Pretty sure now that what I have are a couple of 304s in stock. This is a huge help, many thanks.
You know you have either phonitis or phonosis when your favorite film is "Dial Comes to Town".

Babybearjs

on the BSP 502-400-402, it shows the bell being wired on a 101B coil with the Slate wire being attached to the M terminal and the Slate-Red being attached to the RR terminal. If the bell is wired like this with todays equipment, would it still work?
John

unbeldi

#6
Quote from: Babybearjs on March 06, 2016, 06:34:59 PM
on the BSP 502-400-402, it shows the bell being wired on a 101B coil with the Slate wire being attached to the M terminal and the Slate-Red being attached to the RR terminal. If the bell is wired like this with todays equipment, would it still work?

The wiring you are describing is for message-rate service with zone registration on two-party lines and was only used with standard cross-bar switches having automatic message accounting equipment.

This can only be used with grounded ringing.  I don't think you can find grounded ringing anymore in the US and the tip party identification is useless today.

It doesn't make sense to wire a set that way anymore, unless you have the switching equipment, or showcase original wiring.  So, it is nice to find telephone sets wired this way, because it virtually guarantees that nobody has messed with the set since being disconnected from service.

Here is the circuit diagram for this type of wiring.  The diagram is show in the on-hook state.  When taken off-hook, a ~1000 ohm  (ca. 960 + 11 ohm actually) resistance is placed from tip to ground, which was used by the central office to identify the station number.  Only the tip instrument on this two-party line had this resistance.

MMikeJBenN27

The apartment building we stayed in up until a few years ago still did have grounded ringing.  If a ringer wire was not hooked up to GND, and the yellow wire hooked up to Y in the connection block, it would not ring, and the building we just moved from used 4 wires - red and green for speech, and yellow and black for ringing in many of the units, including ours.

poplar1

Quote from: MMikeJBenN on November 17, 2017, 02:57:17 PM
The apartment building we stayed in up until a few years ago still did have grounded ringing.  If a ringer wire was not hooked up to GND, and the yellow wire hooked up to Y in the connection block, it would not ring, and the building we just moved from used 4 wires - red and green for speech, and yellow and black for ringing in many of the units, including ours.

Roger Conklin stated that some phone companies continued to use grounded ringers, even on individual lines: If the ground wire was no longer connected to the protector, then the subscriber would call in a trouble ticket -- saying that the phone was no longer ringing.
"C'est pas une restauration, c'est une rénovation."--François Martin.

MMikeJBenN27

We have a 354 wall phone with a 4 wire ringer, and wiring the slate lead to "M" and the slate-red to "RR" does NOT require grounded ringing.  Ours rings fine with NON grounded ringing.