The Kellogg Switchboard and Supply Co. commenced the design of the Kellogg 1000 Masterphone in 1935. It was based upon Kellogg's largely successful Triad Circuit which had been developed between 1927 and 1930. By 1935, Kellogg had been producing the Masterphone Series which included the Model 700, 725, 900, 925 and 9917 wall phones. It was at this point that the Mod. 1000 was conceived and designed.
To understand the 1000 Red Bar or redbar, you have to grasp its genesis in the Triad Circuit. This circuit was designed by Kellogg engineers to be universal. That meant that the unit had to be capable of being used in a local battery or common battery circuit, with or without magneto, and/or capable of being used with automatic dial service. In short, the telephone had to be readily convertible and easily adapted to just about any kind of know telephone subscription service available at the time. In order to accomplish this task, the Triad Circuit was designed to contain all of the common components to all known telephone service circuits. Simply changing wiring configurations made it easy to adapt the telephone unit to the needed line.
By 1935, the Autoamtic Electric Monophones had become quite popular with independent telephone companies. AE developed the Model 34 which contained the ringer, condensor and induction coils in one telephone. Kellogg had adapted the Trial Circuit to fit into their 925 desk set, and that was successful, and it had also adapted many ringer boxes or subscriber set models to accept receivers, transmitters and dials. But it was time to develop a telephone that was sleek, compact and very simple in its application.
The 1000 was conceived to accomplish a sophisticated, advanced system with few hitches and virtually no wiring issues that plagued other phone designs. This accomplishment gave rise to a wiring block in which a condensor, an induction coil, and a dial plug would simply plug into unique sockets built into the wiring block itself. A ringer unit would be placed between the induction and condensor coils, and the circuit itself would be sealed against the inside base plate of the telephone to keep dust out of the inner circuit. A dust cover was conceived to fit over the hookswitch, and a single knob was added to operate the hook switch. It is against that knob that the famous redbar plunger presses when the phone is hung up.
The main components of the Red Bar or redbar are the handset (in which a transmitter and receiver capsule are contained, which plug into a pair of male conductors), a handset cord, the wiring block, dial cord and plug, condensor and induction coils, ringer, baseplate, dial OR DIAL STRAPE, base shell, plunger assembly and line cord.
The interchangeable parts are the 35A, 113A and 114A induction coils, #10 or #11 or #15 or #21 dials, and ringer assemblies that include a wide range of harmonic, straightline and straightline biased ringers.
The base shells were as follows: (1) metal desk model (2) bakelite desk model and (3) bakelite wall.
The weakest points on the bakelite 1000 Red Bar are as follows: (1) The base shell around the feet. Usually right front or left rear. These are the points of the shell is likely to be cracked or form hairlines. Next, these are followed by the sides of the cradle. Cracks do develop there too. Finally, some of the earlier handsets develope hairlines and chunking around the receiver cap on the handset. (2) The wiring block or network tends to crack in 2 separate places. The first is center screw post and the second likely place to form a crack is where the line cord screws in.
Magneto or crank Redbars came in several varieties. Metal desk, bakelite with aluminum skirt desk, or bakelite with aluminum or metal skirt wall. Beware of magneto telephones if you intend to use them on a regular phone line. Unless you actually intend to use them as magnetos for an intercom system of sorts, or you actually find a switchboard driven telephone company to use them with, they will not be useful unless converted. Conversion requires several steps. first the magneto has to be disconnected. Second, the 114A induction coil has to be replaced with a 113A induction coil, and finally the wiring block has to be reconfigured for common battery type.
GO TO PART 2