Tyfon Series of Horns from Leslie Company - Part 1

Leslie Tyfon train horns pioneered in blowing in the railroads. It was first launched commercially in 1934. The design of the Tyfon train horns was simple enough to be called as "honkers." The horn is only defined with minimal add-on parts such as the screw-in back cap with a single or a multi-leaf diaphragm. The bell is to be fastened to the base since it is separately designed from it with the sound source. All models in the Tyfon series uses a screw pin for the bell and the base that is properly soldered to construct fixed and single equipment. With this, after the horn is assembled, there's no reason to disassemble them again.

Tyfon A-200-156 - the dominant horn model of the Tyfon horns series used in railroads. Among the array of highly recognized horns from the brand of Leslie, it was the preference of all vehicles on the road. As proof, it was used by almost all vehicle engines fueled by electricity and diesels in the couple of decades of 1930's to 1950's. To cite a few examples, even the most popular types of vehicles such as GG1s, RS3s, ALCO RS1s, FAs, PAs, EMD E and F units, and GP7s adapted the A-200 as their horns. Steam engines of the Southern Pacific Daylight model 4449 also include the A-200 train horns on their vehicles. As a matter of fact, up to this time the sound of A-200 horns of Leslie are still heard in the roads in coming from a few number of old-typed vehicles .

Among the widely used horn models in vehicles and in railroads are the A-200 and A-75 Dual Tone respectively. Thought they were used in a regular basis on switchers or on other smaller engines, the A-125 and A-75 were not as familiar. Among the two, A-75 is the least common since it is only used as derivative horns placed at the back of switchers or on old covered wagons. The dual-tone Tyfons become apparent in the market but have not exemplified the same popularity with other models. However, this type of Tyfons is used up to these times especially on old-modeled steam engines. The dual-tone models are primarily a combination of two Tyfon models framed as one like the dual A-75s, A-125-A-200 and dual A-125s combination. Steam powered engines rarely used A-200 alone however; A-200 is more utilized with other models such as A-125 paired to it. Or, the combined A-125s is preferred over a single-tone horn. Perhaps, these combinations emerged in the horn business despite that it was uncommon.

Labels were used for the streams of Tyfon horns by the year of 1950. The labels used were sufficed, descriptive of the horns' mechanism and function. The labels or names were composed of a combination of letters and numbers corresponding to a certain description of the horn However, this style of naming the Tyfons maybe be vague for some. For a full comprehension of the horn labels, say for example the model A-200-156-PA. The first character is a letter that represents medium of blowing the horn. In this example, A stands for air. S is also used for other models indicative of the steam medium. The number subsequent of the letter determines the size of the diaphragm in millimeters in terms of its diameter. Again, in the example 200 is used which stands for 200 mm. The following number denotes the pitch of the train horn measured in hertz-156 hertz in the example. The pitch can also be represented by D# below middle C. The next character, the letter P in the example identifies the material used in the diaphragm. P is the designation for a phenolic laminate. Some diaphragms are made up of rubberized plastic (R) and metal (M). The plastic diaphragms used were linen cloth that is finely woven and soaked in phenolic substances. It can be compared to the components used at the backs of old televisions only that it is better in terms of durability. The last character is a representation of the horn's material. The materials used for the horn can be aluminum (A) or a bronze (B). So, the model cited identifies the variety of a horn-aluminum Tyfon train horn pitched at 156Hz with a 200mm diameter plastic diaphragm. That is, Tyfon A-75-440-MB provides a bronze Tyfon train horn pitched at 440 Hz with a 75mm diameter bronze diaphragm.