The sony CXD1120P is the electronic volume IC, available he
http://parts.pioneerelectronics.com/...m=CXD1120P%2D1
Flashing volume bars usually indicate the Mute function is engaged... But
if the unit will not unmute with the remote I'd suspect the E-vol IC is bad
or receiving incorrect data, if the mute command is not working properly you
could have a faulty microprocessor, PDG005C. I have seen a few bad in
Pioneer product, but it's not real common.

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Jammy Harbin
J & J Electronics, Inc.
227 S. 4th St.
Selmer, TN 38375
731-645-3311

"Ron Novini" wrote in message
news:2f0a15d6faef17e7744fdf27f22be3bc.123933@mygat e.mailgate.org...
Working on a Pioneer Model RX-1190 Stereo Cassette Deck Receiver with
no volume and a flashing volume display leds. I think that the flashing
leds are indicators of problems. Signal traced the audio from the
receiver
portion (FM). I do have a signal output from the audio multiplexer IC302
(TC9164N). That signal continues to IC303 which I cannot determine
exactly
what it is. It is a Sony CXD1120P (16 pin DIP). The signal stops there
and
does not continue to IC304, a hi performance OP Amp (M5218P). When I
disconnect the input signal from the Sony IC (IC303) and connect
directly
to the input pins of the OP Amp (IC304), I have audio with no volume
control. I suspect that the Sony IC is a volume or signal level control
IC.
Here is the pinouts and voltage measurements that I could determine from
back tracing.

IC303 (CXD1120P)

Pin 1 - Input Right.................0.00v Standby..........0.00v Run
Pin 2 - Ground
Pin 3 - Output Right................-0.35v Standby.........0.00V Run
Pin 4,5,6,7 Connected together
Pin 8 - -Vcc (-12v).................-0.19v Standby.......-12.55v Run

Pin 9 - Clock........................2.060v Standby........1.559v Run
Pin 10 - Data........................2.054v Standby........1.552v Run
Pin 11 - Vol St (VRST)...............0.001v Standby........0.008v Run
Pin 12 - ?...........................0.030v Standby........2.719v Run
Pin 13 - +Vcc (12v)..................0.134v Standby.......11.84 v Run
Pin 14 - Output Left................-0.053v Standby........0.454v Run
Pin 15 - Ground
Pin 16 - Input Left..................0.030v Standby........0.008v Run

Some notes apply:
-When I disconnected Pins 9,10,11 (Clock,Data,Volume), the front volume
led display still flashes. May I have a problem with the controller IC
on the front panel (IC103 PDG005-C)?
-Pins 9 and 10 have the recognizable clock and data pulses. However they
seem to pulsate in time with the led flashing.
-Pin 11 does receive pulses when the volume is being adjusted.
-Power supply inputs measured ok. (-10v line measures -9.96v,5.6v line
measured 5.36v). 12volt line measures 11.86 v. 5 volt line measures
4.79 v.
-Muting line measures 4.65 volts at run.

My dilemma is twofold. Do I have a defective controller in protect mode
or do I have a so-called defective volume (signal level) IC? When the
volume ic is disconnected, the flashing display still persists.Any help
would be appreciated. Thanks ahead, Ron


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