104 VS.. 101 induction coil

[sebbel]

What is the different between the 2. Is one meant for local battery while the other isnt? Can I put a 104 in a 302 to replace the 101?

[poplar1]

104 is LB and 101 is CB. I don't think they are interchangeable

[G-Man]

The 104 was intended for use on either Local Battery (magneto) or Common Battery (manual or dial) lines.

Magneto service was designated as L.B.T/L.B.S. (local battery talk/local battery signaling) and Common Battery (manual or dial) service as L.B.T./C.B.S. (local battery talk/common battery signaling).

Local battery service was used on common battery lines to boost a distance subscribers voice when they were located many miles from the central-office.

So yes, you could use it in a 302 along with a separate battery, but be forewarned that your voice may be too loud.

[G-Man]

Here is a description from the BSP regarding sets using 104A induction coils:

2.17  The 307-type telephone set is a local battery talking,
        common battery signaling anti-sidetone combined-type
set similar to the 302 set in appearance. It is for use on none
polarized ringing lines of the same classes of service listed in
2.01 for the 302 set.

  2.18  The manual sets are coded 307A and 307E and the dial
        sets are coded 307B, 307C. 307D, 307F, 307G, 307H.

    2.21      The   309-type    telephone   set   is   a   local   battery   talking
             common   battery   anti-sidetone    signaling    set    for    use
  with four-party selective and eight-party semi-selective services.
  It is similar to the 307-type except that it employs the B3A
  ringer, 195C condenser and in addition a 405A or 426A vacuum
  tube. The manual set is coded 309A and the dial set 309C.

[sebbel]

Right. The 104 need a battery to get passed that huge resitor on it. I removed the resistor, replaced it by a simple wire. I put it in my project 302 and it seems to work just fine. No I just need to find a cheap 302 ringer.

[Babybearjs]

on my 307's, I don't use the resistor on board. its bypassed.