Crown Audio IQ-USM 810 service manual Typical Measurements, Test/Debug Objects, Hi-Pot

130447-1 Rev. A IQ-USM 810 Service Manual

4.6.20 CHASSIS GROUND

Spec: Ground conductor of the power inlet is connected to chassis ground.

Note: This test to be completed after the complete product assembly.

Procedure:

Verify power inlet less than 1 W between connector ground and chassis.

Recommended chassis test points:

RS232 Connector shell or screw locks, Multi-Function Control Port shell of screw locks or Crown bus connec- tor shield.

4.4.21 HI-POT

Spec: Power Supply withstands Hi-Pot spikes.

Procedure: Verify unit allows no breakdown leakage current with a 1-second, 1.2-kV Hi-Pot from AC mains (Hot and Neutral) to earth ground.

4.7 Typical Measurements

Output Noise 20 Hz to 20 KHz bandwidth, line mode: –77 dBu

Frequency Response 20 Hz to 20 KHz, referenced to 1 KHz, line mode: –0.27 dB.

Harmonic Distortion THD+N, at 1 KHz, 20 Hz to 20 KHz bandwidth, line mode, 0 dBu input: 0.013 %.

Common Mode Rejection at 60 Hz, line mode: –66.5 dB.

Head Room / Input Clip Level highest input level be- fore 1 % TDH+N, Line mode: –.131 % TDH+N @ +20 dBu.

Input Potentiometer at 1 KHz, 0 dBu input:

Potentiometer

at –12 setting: –12.85 dB

at +20 setting: +20.43 dB

Phantom Supply between each signal pin (“+ and “–”) and ground of each input: 25.77 VDC

Control Port Output Voltage Pins

5 volt supply (between pins 9 and 10): 4.92 VDC 10 volt supply (between pins 29 and 28): 10.26 VDC

4.8 Test/Debug Objects

Object Number

Dec Hex/ASN1 Description / Command string format

704$2C0

$C0 $05

768$300 $80 $06

705$2C1

$C1 $05

Bus Master: Allows manual control of the bus master function. (Normally an internal func- tion of the Ucode protocol). With this object set, no IQ bus, communication passes through the IQ-USM 810 Crown bus port.

Send: DA DT CT C0 05 09 01 CS; to master the IQ Bus, open the loop

Response: None

Send: DA DT CT C0 05 00 CS; to unmaster the IQ Bus, close the loop

Response: DA DT AK CT 00 CS; standard ACK

Display Test Mode: Cycles each section of the display through a known sequence allowing the operator to verify that all segments and indicators are functional. See Section 4.7 for known sequence.

Send: DA DT CT 80 06 09 01 CS; To force the preset LED on

Response: DA DT AK CT 00 CS; standard ACK

Send: DA DT CT 80 06 09 00 CS; To set the preset LED in normal mode

Response: DA DT AK CT 00 CS; standard ACK

Pushbutton Test: Reads a single byte that is bit mapped to indicate a pushbutton depres- sion (bit 0 = “SEL” depressed, bit 1 =”∧ ” depressed, bit 2 = “∨ ” depressed):

Send: DA DT CT C1 05 0A CS, To get data

Response: DA DT AK CT C1 05 0C BTN CS

©2000 Crown International, Inc.

Maintenance 4-7