Zenith J584W - Page 19

TABLE A - "J LINE" STEREO CHASSIS COMPARISON
CHASSIS
MODELS
DESCRIPTION
1WJR55
Consoles New one circuit board chassis. FM uses separate Bipolar RF, Oscillator
J900P
and Mixer transistors with one IF IC and one PLL Multiplex IC. AM
JR900P
uses one IC for RF, Oscillator, Mixer and IF. Audio uses one transistor
JR900P1
J902P
JR902P
J903PN
and one Output IC in each channel.
JR903PN
3WJR50, 50Z
Consoles
New two circuit board chassis with boards being common to both chassis.
J915P
FM uses separate Dual Gate MOSFET RF, Bipolar Oscillator and Mixer
JR915P
transistors with one IF IC and one PLL Multiplex IC. AM uses one IC
J916M for RF, Oscillator, Mixer and IF. Audio uses discrete transistor circuitry.
JR916M
JR919P
JR920AE
JR922M
Chassis 3WJR50 is also provided with a tuning meter.
3WJR52, 52Z
Modulars
J587W
JR587W
JR588W
3WJR51
Modulars
J584W
J584W1
Chassis continued similar to "H Line" 3WHR50 and 3WHR52.
8WJR56
Modulars
Chassis similar to 6WHR56, 6WHR57 and 12WHR29 but with the addition
JR684W
of a preamp circuit (bipolar transistors) for a magnetic phono cartridge
JR684W1
and also an increase in the rated power output.
8WJR57
Modulars
J590W
JR590W
JR590W1
JR591W
15WJR29
Modulars/Console
J596W
JR596W
JR966P
New "J Line" chassis designs exhibit changes in both mechan 
ical structure and electronic circuitry. "Mini-Wedge" Models
J587W, JR587W and JR588W use Chassis 3WJR52. Model
JR587 is illustrated in Figure 1. As you will note, this model
continues the "Wedge" concept, but at a reduced size, result 
ing in a "Mini-Wedge" appearance. Mechanical structure of
Models J587W, JR587W, JR588W and Chassis 3WJR52 will
be discussed in some detail later, but for now we will look at
the chassis electronics. Features listed above for Chassis
12WGR59 and 12WHR29 provide some insight as to what may
be expected in the "Mini-Wedge" concept. (Chassis 3WJR50
has a tuning meter in addition to the same circuitry as chassis
i 3WJR52.)
Features included in Chassis 3WJR52 are:
1. Separate RF and IF circuits for AM and FM.
2. One Integrated Circuit for AM RF/Oscillatpr/Mixer/IF
(IC101).
3. Separately mounted AM Oscillator Trimmer (C103).
4. Ceramic Filter in AM IF (Part of T102).
5. Separate FM RF, Oscillator and Mixer Transistors (Q1,
02,03).
6. Ceramic Filter in FM IF (Y201) and only one FM IF
Transformer (T201).
7. One Integrated Circuit for FM IF Gain Block, Limiter and
Quadrature Detector (IC201) with one adjustable coil
(L203).
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