15
Amplifiers & Preamplifiers
7.
When I select input #1, no sound plays through. Inputs #2 through #8 work just fine.
a) Make sure the source plugged into input #1 is actually working by trying it on one of the other
"working" inputs.
b) If the source is proved to be OK, plug it into #1.
c) Connect an IR receiver to a zone IR input.
d) With the source playing, aim the RC68 at the IR receiver and press input #1 and then the TRIM
button.
e) Press the VOLUME up button to achieve max. volume, then down a step or two.
f) Press input #2, then ADJ-OFF. Input #1 should now play OK.
g) Go to SETUP PROCEDURES and redo the Input Level TRIM adjustments.
8. I have a keypad (or an IR receiver) connected to one of the zones through a long length of
multiconductor shielded cable (sometimes even with very long lengths of unshielded cable).
Commands for some of the components work just fine, but others do not work at all or are very
intermittent.
a) Connect a 470 Ohm 1/8 Watt resistor between INPUT and GND on each of the offending zones. Refer
to Fig. 7 under INSTALLATION section for details.
The capacitance of the shielded cable prevents high bit rate commands from passing through unaltered.
The resistor effectively discharges the capacitance, correcting the condition.
See next page for ZPR68-10 Block Diagram
ZPR68-10
AUDIO (ea. channel)
Gain (@ max VC*): ............................................................................................................................... Unity
Input Overload: .................................................................................................... > 4 V RMS (@ max VC*)
Input Impedance: ..................................................................................................................... > 40 k Ohms
Output Impedance: ...................................................................................................................... 470 Ohms
Signal to Noise: ................................................................................................................. 96 dB (re 2V out)
THD: (VC -10 dB) .................................................................................................... 0.01% at 2V input level
Frequency Response (
±
3 dB): ............................................................................................. 5 Hz to 70 kHz
Bass Control Range (@ 100 Hz): ...........................................................................
±
12 dB (in 2 dB steps)
Treble Control Range (@ 10 kHz): .........................................................................
±
12 dB (in 2 dB steps)
VIDEO
Input/Output Impedance: ............................................................................................................... 75 Ohms
Video Insertion Loss: ........................................................................................ < 1.0 dB (50 Hz to 10 MHz)
GENERAL
RC68 Code Group Number assigned to the ZPR68-10 ........................................................................... 68
Control (CO) & STATUS Outputs ............................ 12 V @ 10 mA, 9 V @ 90 mA (90 mA is max. current)
Max. Total Current Available From +12V, STATUS & CO Terminals .................................................. 1.8 A
Power Requirements: .......................................................... 14V-0-14V AC @ 2.7 A, 8V-0-8V AC @ 0.7 A
(Multi-Voltage Power supply included)
Gold Plated RCA type phono jacks ............................................................................ All A/V inputs/outputs
Dimensions: ............................................................................................................... 14" W x 7 " H x 2.5" D
Weight: ........................................................................................................................................ 4 lbs, 3 oz.
Note: *VC = Volume Control setting
SPECIFICATIONS
