P Series Train Horns

The concept of the P series is inspired by a truck horn adding modifications in order to configured it for railroads. Horns of the P series are simple but toughly created. A bell housed with a diaphragm, mounting floor, nozzle and orifice composed this horn type. The horn has no diffuser and has only one diaphragm disk. Models that were manufactured lately had a pair of disk. However, it had not exemplified an importance on the horn itself. The secret of its robustness is the design itself. A rubber gaskets support the diaphragm while another gasket covers the mouth of the nozzle. This accounts to the fact that gaskets and seldom the diaphragm are the only components that can have a P horn.

The horn is assembled by covering the nozzle with a nozzle gasket. Use the included spring to lock the nozzle gasket in place. Subsequently, place the diaphragm on the bell with the larger gasket covering it while the smaller gasket covering the outer edge. Positioned on their respective places, tread the diaphragm housing and the back cap with the six screws. To be a fully functional model, slots for the screws were initially designed plus its star-shaped lock washers.

With the least assembling effort and process, the P horn works efficiently. Problems occur minimally and can be solved with simple and least troubleshooting efforts. Usual problems may only be due to worn gaskets or soiled diaphragm. By just dismantling the back caps in order to clean the diaphragms or replace the gaskets, the P horn can sooner function satisfactorily. Though the P horn can work with impaired components, it is still recommended to replace worn or broken parts promptly like the diaphragm to avoid serious defects.

An array of experiments was conducted to assess the competence of the horn. Moreover, the intensive testing had lighted innovations for the P horn. Nathan had included a variety of bells in the P horn within the past years. People fueled by their innate creativity made use of these bells to compose chord patterns. There is no doubt about the fact that the number of horn bells can produce 11 notes.

Here are the bells with their corresponding chord. OC is the old cast or second generation while the NC is new cast or third generation of bells.

• O—A
• OC 1—C#
• NC 1—D
• OC 2—E
• NC 2—F
• OC 3—G
• NC 3—G#
• 4—A
• 4A—A#
• NC 5—C
• OC 5—C#

When these chords were combined, a melody is achieved.

A series of test on the number and size of diaphragms were also conducted. The first P horns used a single diaphragm disk while a couple of disks were adapted on later models. The “chiff” characteristic was reduced with the use of double-disk P horns when the horn is initially blown and when the sound intensifies. It was also discovered that the thickness of the diaphragm contributed to the same effect. In connection to the findings, the 0.008 thickness of the stainless steel P diaphragm gradually increased up to 0.0025-thick. This caused in considerable improvements on the horn’s tone. The material used for the diaphragm is also experimented taking into consideration the thickness as well. Phosphor bronze was utilized as the material. The result exhibited that the thickness of the bronze material is proportional to the quality of sound or melody produced by the horn—the thicker the bronze, a better melody is achieved.