geoelectro

Servicing the Hammond B-3 Type Pre-Amp

AO28 Layout AO28 Schematic General Description The AO-28 tube pre-amp is found in the Hammond B-3 as well as several other models. C-3, A-100, RT-3, D-100 etc. Designed in the fifties, this pre-amp remained in production until 1975. And, it remains fully functional and serviceable today. This discussion is designed to help owners do some

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Servicing the Hammond B-2/C-2 Type Pre-Amp

Table of Contents AO10 Layout AO10 Schematic General Description The AO-10 tube pre-amp is found in the Hammond B-2 as well as several other models. C-2, RT-2. Designed in the forties, this pre-amp remained in production until 1948. And, it remains fully functional and serviceable today. This discussion is designed to help owners do some

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Servicing the Hammond Tone Generator

Technical Description From Service Manual Each Hammond Organ Console has a main generator within it, and in some cases, depending on the model, a chorus generator. The main generator consist of the generator proper, a shaded pole induction motor for starting, a non-self-starting synchronous motor for driving the unit after starting, and a vibrato scanner mounted on the run

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Hammond Generator Filters

General Description From the Service Manual: As a means of eliminating any vagrant harmonics that may be present, there are filters consisting of small transformers and condensers associated with certain frequencies. The transformers have a single tapped winding, and this tap is grounded, so one side, which is connected to the corresponding magnet coil through

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Tone Wheels

General Description From Service Manual. Each tone wheel is a steel disc about two inches in diameter, accurately machined with a definite number of high and low points on it’s edge. Each high point on a tone wheel is called a tooth. the number of teeth on each of these tone wheels, in conjunction with

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Hammond Synchronous Run Motor

General Description The run motor is a non-self-starting synchronous motor. Rather than delivering a constant power, it delivers a series of pulsations, one for every half cycle. That would be two pulses per cycle and 120 pulses per second with a 60 cycle current source. RPM is 1200 for 60 cycle motors. 1500 for 50 Cycle. These motors do not usually have many

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