Service manual

44
Sources with IR input on back panel
Many sources, particularly tape decks and tuners, have no IR input to the front panel. These products are
designed for use with receivers and a “system” remote. Some tape players and other source components
have opto-isolated IR inputs as with Harman Kardon equipment. With these components, plug the emitter
outputs of the PX-600 directly into the IR inputs on the back panels using mono mini plug to mini plug
cables.
When the IR inputs are not opto-isolated, route the IR through a CD player in the system that is the same
brand and series, and connect the CD player via the IR port to the back of the tape deck. Use the ALL
OUTPUT in this case. If this is not an option consider using a Xantec 794/797 connecting block and route
the IR signal through this device which provides opto-isolation for the source component.
Using a CD Player on the Tape input
The programming is the same for PLAY, STOP and SKIP DISC (SKIP TAPE). However, enter SKIP
TRACK for both REVERSE PLAY and FORWARD PLAY. Then each time you press TAPE on the
transmitter, keypad or front panel, you will get SKIP TRACK on the CD Player.
Laser Video Disc Players as main CD Players
Many current LD players play regular CDs as well as laserdiscs. One may be tempted to use these players
as both the CD and VIDEO source. We recommend a separate, dedicated CD player on the CD input.
However, if you must use the LD/CD arrangement, please consider the following:
Split the audio output into both the CD input and the VIDEO input of the PX-600. If you're using some
other means of video switching, connect one of the splits into that device and then into the PX-600. In this
way the audio will track with the labeling on the keypad.
LD players often have PLAY/PAUSE buttons which means you will undoubtedly get PAUSE at some point
when you really want PLAY.
LD players often have STOP and EJECT on the same button, so it is likely that the drawer will open when
you don't want it to. You may opt to eliminate the STOP command altogether.
If you plug the LD player into the PX-600 for AC power, it may power up into a “standby” mode. Before it
accepts any other commands, the player needs the IR POWER command. Use the POWER command from
either the CD or the VIDEO input - not both. You can get around this on some players by setting the timer
to the “on” position if it has this feature (this solution
may
work for
any
equipment with stand-by power).
Sharing Sources with Other Systems
Some pre-amps, receivers and A/V surround receivers short their audio inputs together when they are turned
off. This will show up in the PX-600 as cross talk between CD, TAPE, AUX and VIDEO if the PX-600 is
on and the other system is off. This cross talk or bleed from one source to another is often accompanied by
low frequency distortion. One solution is a line level switch made by Sonance, Model AL-1S, which has
A/B switching between multiple sources and provides the necessary isolation. It requires a 12VDC power
supply, also available from Sonance, and is reported to work perfectly in this situation. The only other way
to deal with it is to build a relay circuit that isolates the preamp or receiver from the source equipment when
it is off.