ZETRON 27 User manual

/
Z E T R 0 N
Model 27 Receiver Monitor Panel
Technical Manual
#025-9186D
EXPERTS IN M IS SIO N-C RITIC A L COM M UNICATION SYSTEMS
[ Z E T R O N )
^ i ■■■■■■■ ■mi

Z E T R 0 N
Model 27 Receiver Monitor P nel
Technic l M nu l
#025-9186D
COPYRIGHT 1991 1992 ZETRON INC.

TABLE OF CONTENTS
Operation ...................................... 1
"Call" LED .................................. 1
"Mute" button and LED
.......................... 1
Speaker volume
............................... 1
Specifications .................................. 1
Installation .................................... 2
Power
..................................... 2
Audio signals ................................ 2
Busy/mute signals ............................. 3
Input level adjustments
......................... 3
Mute level adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Minimum volume level adjustments . . . . . . . . . . . . . . . . . . . 4
Labeling
...................................... 4
Service diagrams ................................. 5
Model 27 receiver monitor panel parts list (901-9233B) .... 5
Model 27 receiver monitor parts list (702-9372E)
........ 6
Model 27 receiver monitor panel schematic (008-9372E)
..... 9
Model 27 receiver monitor panel silkscreen (702-9372E) .... 13

WARRANTY
Zetron Inc. warrants that all equipment sold pursuant to any resultant
agreement shall be free from defects in material or workmanship at the time
of delivery. Such warranty shall extend from the time of delivery for One
Year. Buyer must provide written notice to Zetron within this prescribed
warranty period of any defect; if the defect is not the result of improper
usage service maintenance or installation and equipment has not been
otherwise damaged or modified after delivery Zetron shall either replace
or repair the defective part or parts of equipment or replace the equipment
or refund the purchase price at Zetron's option after return of such
equipment by buyer to Zetron. Shipment to Zetron's facility shall be borne
on account of buyer.
1. Consequential Damages: Zetron shall not be liable for any incidental or
consequential damages incurred as a result of any defect in any equipment
sold hereunder and Zetron's liability is specifically limited to obligation
described herein to repair or replace a defective part or parts covered by
this warranty.
2. Exclusive Warranty: The warranty set forth herein is the only warranty
oral or written made by Zetron and is in lieu of and replaces all other
warranties expressed or implied including the warranty of merchantability
and the warranty of fitness for particular purpose.
COPYRIGHT NOTICE
The software in this product is copyrighted by and remains the property of
Zetron Inc. Reproduction duplication or disclosure is not permitted. No
part of this document may be copied or reproduced in any form without the
prior written consent of Zetron Inc.

MODEL 27 RECEIVER MONITOR PANEL
OPERATION
The Model 27 Receiver Monitor Panel contains two identical and independent
audio circuits: one on the left and one on the right. Each circuit features
four receiver audio inputs each with its own "Call” LED "Mute" LED and
"Mute" button. In addition each circuit has a knob to adjust the overall
volume of the circuit's speaker.
"C ll” LED
When audio traffic is present on a receiver its "Call" LED will blink.
The "Call" LED will illuminate steady if the receiver is being muted
externally. Normally external muting is performed if the receiver is on the
same frequency as a transmitter that is being operated within acoustic
range of the Monitor Panel. External muting prevents audio feedback.
"Mute" Button nd LED
Pressing the receiver's button will mute the receiver's audio. This is
indicated by the illumination of the "Mute" LED. Pressing the button again
will unmute the audio causing the "Mute" LED to extinguish.
Spe ker Volume
The knob under the speaker is the master volume control for the four
receivers associated with the speaker. Turning the knob clockwise will
increase the volume level. Turning the knob counter-clockwise will decrease
the volume level. Turning the knob fully counter-clockwise may not
completely turn off the volume (depending on adjustments made at
instal1 at ion).
SPECIFICATIONS
Power
Size
Weight
Configuration
Busy/Mute Inputs
11 to 16 Volts DC. 0.3 A typ standby 2.0 A max (full
output).
5.25" high 19.00" wide 1.50" deep
5 lb.
Two independent audio circuits each with four mutable
audio inputs summed to feed a single speaker with
volume control.
Each audio input has an associated Busy/Mute Input
which when shorted to ground mutes the audio
input.
1

MODEL 27 RECEIVER MONITOR PANEL
Audio Inputs
Impedance: 10 000 ohms or 600 ohms balanced (60 dB) DC blocking.
Level For Full Output:
-30 to +10 dBm adjustable (unmuted).
Mute Level: 0 to 40 dB adjustable level reduction compared to
unmute.
Frequency Response:
150 to 12K Hz
Speaker Outputs (at 13.8 VDC power 1 kHz tone)
0.2 % typ. distortion at 2 Watts output.
10 % maximum distortion at 5 Watts output.
INSTALLATION
The Model 27 Receiver Monitor Panel is designed to be installed in 19" EIA
compatible rack furniture. The rear cover of the Monitor Panel gives clear
indications of signal names and locations.
Power
The removable screw terminal block Jl located near the center of the rear
cover is used to route power to the Panel. 11 to 16 Volts DC should be
used. The positive lead should connect to pin 5 or 6 of Jl. The negative
lead (which is also connected to chassis) should connect to pin 7 or 8 of
Jl. When the Panel is used in conjunction with other Series 4000 products
it may share the power from those products. Keep in mind that if full
output power is desired the Monitor Panel may draw as much as 2.0 Amperes.
Audio Sign ls
Both circuits labeled "Left" and "Right" have four receiver audio
channels labeled "A" "B" "C" and "D". These correspond to the Buttons
and LEDs on the front of the Panel as follows: top=’'A" next down="B" next
down="C" and bottom="D".
Each receiver audio input is transformer coupled with a DC blocking
capacitor in series. The impedance of the audio input is 600 ohms as set at
the factory. The impedance may be altered to 10K ohms by changing jumpers
located on the circuit board to the "B" position.
Audio signal pairs are connected to the panel using removable screw
terminal blocks Jl J2 and J3 as follows:
Channel B1 ock Pins Impedance Jumper
Right-A Jl 3&4JP1
Right-B J2 3& 4 JP2
Right-C J2 7 & 8 JP3
Right-D J2 11
&
12 JP4
Left -A Jl 11 &
12 JP5
Left -B J3 3
&
4 JP6
Left -C J3 7
&
8 JP7
Left -D J3 11 & 12
JP8
2

MODEL 27 RECEIVER MONITOR PANEL
Busy/Mute Sign ls
Each receiver audio input has an associated Busy/Mute input which when
shorted to ground will completely mute the audio input and steadily
illuminate the receiver's "Call" LED. This is most often used if the
associated receiver is monitoring the same frequency as a transmitter that
is operated from a location within acoustic range of the Monitor Panel. The
Busy/Mute input is usually derived from the PTT signal of such a
transmitter.
Busy/Mute signal pairs (labeled "X-Busy" on the rear cover) are connected
to the panel using removable screw terminal blocks Jl J2 and J3 as
fol1ows:
Channel B1 ock Pins
Right-A Jl 1 & 2
Right-B J2 1&2
R i g h t - C J2 5 & 6
Right-D J2 9&10
Left -A Jl 9 &10
Left -B J3 1 & 2
Left -C J3 5 & 6
Left -D J3 9& 10
Input Level Adjustments
Each receiver audio input has two adjustments; the "Input Level" and the
"Mute Level".
1 he "Input Level" adjustment is a four-turn trim potentiometer located
within the cut-out area of the rear cover. Turning this pot clockwise will
decrease the attenuation of the input signal. When turned fully clockwise a
-30 dBm level (25 mVrms) will be capable of producing the full 5-Watt
rating on the associated speaker.
Recommended Procedure: Turn the "Input Level" adjustment fully counter
clockwise (no more than four turns or until clicking is heard). Place a
signal of typical level across the associated audio input pair while
observing the associated "Call" LED. Turn the "Input Level" adjustment
clockwise until the "Call" LED begins to blink. Turn the adjustment one
additional turn clockwise to ensure proper dynamic range of the "Call" LED.
Once each of the four inputs have been adjusted it may be desirable to
compare the listening level of each and readjust the "Input Level" to bring
all inputs to a comparable listening level.
3

MODEL 27 RECEIVER MONITOR PANEL
Mute Level Adjustments
The "Mute Level" adjustment is a single turn potentiometer located next to
the associated "Input Level" pot. Turning this pot clockwise will decrease
the attenuation of the mute level. This adjustment sets the mute level
relative to the "Input Level" adjustment (i.e. the absolute mute level is
affected by the "Input Level" adjustment).
In order to adjust the "Mute Level" the associated mute function must be
activated by pressing the "Mute" Button such that the "Mute" LED turns on.
The "Mute Level" may then be adjusted to the desired listening level. If
full mute is desired the adjustment should be turned fully counter
clockwise.
Minimum Volume Level Adjustments
Each speaker has a "Minimum Volume Level" adjustment. This allows the
setting of the lowest volume achievable when the master knob on the front
panel is turned fully counter-clockwise. When this single turn trim
potentiometer is turned fully counter-clockwise the minimum volume level is
zero (no sound). Turn the trim pot clockwise in order to increase the
minimum volume level above zero.
LABELING
The "Mute" Buttons feature removable transparent covers. It is suggested
that labels be inserted under the covers which identify the name of the
associated receiver.
4

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1. TEST AND CALIBRATE ACCORDING TO
PROCEDURE 02Q-C12 .
0=0 CUT WIRE, ITEM 16, INTO FOUR 4' PIECES,
SOLDER 2 TP EACH SPEAKER. ITEM 13, CONE
PER TAB>. CRIMP THE OTHER
ENDS TO IDC CONNECTOR, ITEM 15.
GD INSTALL IDC CONNECTOR, ITEM 15, INTD JP9
AND JP10 OF BOARD, ITEM 2 .
£T> SECURE U19, U20, U28, U29 TO BOARD
ITEM 2 , AND FRONT PANEL. ITEM 19,
VITH SCREVS, ITEM 5,
GO PLACE ITEMS IN PLASTIC BAG, ITEM 23.
SO PLACE ITEMS IN PLASTIC BAG ITEM 24,
, PLACE UNIT IN BAG ITEM 25,
EO PLACE LABEL ITEM 1 , ON BACK OF UNIT.
2 i 02-93 2 M2 REC, MON, BOARD
26 A/R 561-0003 ADHESIVE
25 1449-9052 BAG PLAS, 10X8X24 1,5 GA
24 1449-9042 BAG PLASTIC 2X3 ,004 GA
23 I449-9019 BAG PLASTIC 5X ,004 G-
22 I449-9016 BOX, CDBD V/FDAM ENDS
21 1416-1202 1FUSE AGC 2A
20 1415-9504-1 M2 DL MN PN REAR COY
19 1415-9582-1 M2 REC MN FRDMT PANE_
18 2415-9193 M20 TBLTOP SPEAKER GRI_
1 1415-9003 DECAL. TI-5100 PN/SN/IFT
16 16' 408-2201 22 GA, VIRG VHITE
15 2 401-01 5 2 COND IDC, 26 GA X .1
14 3401-0016 12 PDS BLOCK FEMALE
13 2 305-0021 SPEAKER 4 OHM 5V
12 2 265-0013 CAP FOR 265-0012
11 2 265-0012 KNOB V / INDICATOR BLK
10 251-1239 440X.031 NYLON
9250-0105 440X3/8 V/STUL
8250-0103 440X3/4 V/STUD
4236-0004 VASHER, NYLON *10 BLftC*.
64220-0250 1032X3/4 FLT HD PHIL
54220-0108 440X1/4 PAN PHILLIPS
410 220-010 440X3/16 PAN PHILLIPS
38210-0001 440 KEPT NUT PG4TED
21108-0000 A' 1GNMENT TOOL
11025-9186 k? REC. MflN PAN. MANUAx.
ITEM QTY. PART « ! DESCRIPTION
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5

MODEL 27 RECEIVER MONITOR PANEL
Model 27 Receiver Monitor P rts List (702-9372E)
LEGEND:
i = NOT INSTALLED
A = INSTALLED ON HIGHER ASST
+ = OPTION (INSTALLED PER CUSTOMER ORDER)
ITEM
m
COMPONENT REFERENCE PART NO. DESCRIPTION MANUFACTURE P/N
1 6 R4 R42 R123 R130 R163
R176 101-0010 1 OHM 1/4W 5* CARBON FILM 1/4-51
2 4 R12Q R128 R132 R175 101-0013 2.2 OHM 1/4W 5* CARBON FILM
314 R18 R40 R57 RB1 R96
, R115
R127 R129 R131 R140 R160
R170 R171 R172
101-0057 220 OHM 1/4W 5% CARBON FILM
4 2 K179 R1SQ 101-0061 330 OHM 1/4W 51 CARBON FILM
5 8 R6 R23 R24 R64 R65 R70
R103 R104 101-0068 620 0 1 1/4W 51 CARBON FILM
6 18 R10 R12 R32 R34 R46 R48
R73 R75 R87 R89 R1Q7
R109 R125 R133 R152 R154
R174 R178
101-0073 IK 1/4W 5? CARBON FILM
78R22 R44 R61 R85 R100
R119 R144 R164 101-0085 3.3K 1/4W 5% CARBON FILM
8 52 Rl# R2 R3|lR5fR7(R8(R9
Rll R13/RI4lR16 R21 R25i?y
R26yS27 R28 R29yR30 R31#J
R33 R35 R36(R37 R45 R47
R49 R50(E55 R60 R68 R69
R74/R76 R77 R78 R86 R88/
R90 R91 R94 E99 R108
R110 S111 R112 R134 R135
R136 R138 R143 R153 R155
R156 R158 R165 R177
101-0097 10K 1/4H 51 CARBON FILM
9 1 R149 101-0105 22K 1/ffl 5% CARBON FILM
10 1 R148 101-0121 100K 1/4W 5% CARBON FILM
11 8R19 R41yR58 R82 R97 R116
R141.R161 101-0125 150K 1/4W 5% CARBON FILM
12 10 R15 R17# R38(R39# R54#
R56# R79 R80# R93 R95$
R1I3 R114# R122IR137
R139# R157 R159# R167
101-0145 1M 1/4W 51 CARBON FILM
13 2 E173 R126 107-0002 10K R0T0SY POT RH1631110-1O KB
14 2R169 R121 107-0202 2K POT 1 TURN 3386P-1-202
15 8R53 R63 R67 R72 R102
R106 E147 R151 107-0502 50K POT 1 TURN 3386P-1-503
16 2 R166(R124 107-0504 20OK POT 1 TURN 3386P-1-204
17 8 R52/R62 R66 R71JR101
R105 R146 R150 108-0103 10K POT 4 TURN 1102P-1-103K
18 8 C4 C15 C17 C23 C26 C42
048 C55 150-0096 1000 PF 1KV 1-20! CERAMIC DISC GE-102G
19 1C56 150-0110 .01 UF 50V 80%-20% CERAMIC DISC DF-1032
6