Document mmpq8N4dRG4np3paLV4mY94ad

PLAINTIFF'S EXHIBIT ERVICE BULLETIN SEPTEMBER 1, 1977 l\lo. Q88a under BRAKES FOR BRANCHES. DISTRIBUTORS AND CUSTOMERS. CHASSIS AFFECTED ALLENTOWNQ'HAYWARD 0* OAKVILLE 0" RADIO NOISE SUPPRESSION (All Models Equipped With Anti-Wheel Lock Brake System) PURPOSE To instruct owners and operators how to suppress radio noise on subject vehicles. RECOMMENDATION When radio noise is encountered, follow instructions in this bulletin. INFORMATION Operator complaints of undue noise from radio speakers (AM-FM, tape players etc.) have been received. This could be the result of poor grounding of the radio chassis to the vehicle chassis. A poor ground can aggravate conditons whereby brake controller hum and vehicle borne noise can be carried through the power line to the radio and then through the speaker system. If after insuring that the grounding is satisfactory, and radio noise is still excessive, proceed as follows: CAUTION Electrolytic capacitors are polarity sensitive, having both a positive and negative end. Use caution when in stalling. Connect a 100 MFD capacitor having a 50 volt WVDC (working voltage, direct current) from the radio power lead to the vehicle chassis as illustrated in Fig ure 1 for positive ground or Figure 2 for negative ground, depending on the vehicle electrical system. NOTE The 100 MFD capacitors with a 50 volt WVDC are available from radio/TV repair shops or stores such as Lafayette Electronics, Radio Shack, etc. CIRCULATIC Service Manager Shop Foreman flight Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room 3. VEHICLE CHASSIS 4. too MFO CAPACITOR 50 WVOC FIGURE 1 POSITIVE GROUND 4. 100 MFO CAPACITOR - 50 WVOC PIGURE 2 NEGATIVE GROUND Service Operations, Allentown, Pa. U. S.A. Shop Office Mack~