NAD Technical Bulletin T743-H2005-06 describes the problem "Unit may shut down, shortly after turn on". Reason: There is a diode on the standby board that maybe operating intermittently. Solution: Locate and identify D756 on the standby board. Change only if the diode is a 1N4148. Change from a 1N4148 to a 1N4004 or equivalent.
It is located near a transformer and some fuses.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
The reference to Zone 2 means that your Onkyo receiver is set to be remotely controlled from another location. Normally, this arrangement would be initiated at the time of set up but could be done later. You may have to repeat the initial set up routine to get things back to normal
They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.
A heat sink is just a finned heat-conducting device for radiating heat to the air which should be flowing freely through the unit's ventilation holes. It can't break in normal use. But it CAN get clogged with dust reducing its effectiveness.
Register and download the manual for free at retrevo.com
"Choose a location that is well ventilated (with at least several inches to both sides and behind), and that will provide a clear line of sight, within 25 feet/8 meters, between the receiver's front panel and your primary listening/viewing position-this will ensure reliable infrared remote control communications. The T 743 generates a modest amount of heat, but nothing that should trouble adjacent components. It is perfectly possible to stack the T 743 atop other components, but the reverse usually should be avoided. Nonetheless, it is generally preferable that the T 743 stand alone. It is especially important that sufficient ventilation be provided; if you are contemplating locating the T 743 within a cabinet or other furniture, consult your NAD audio/video specialist for advice on providing adequate airflow."
If you're lucky, you haven't finally toasted it. If you have, a hands on tech will need to sniff sround (literally) to find the dead component(s).
While working it stops and flashes red approximately
2 seconds interval Causes Protection circuit is activated
depending on the temperature of the surroundings Remedy Switch off the power supply and power on
after the temperature have reduced. While working it stops and flashes red approximately
0.5 seconds interval Causes 1.Using speakers having less impedance
than the specified. 2.If speaker core wire touch each other Protection
circuit is activated Even applying power red flashes 0.5
seconds interval Cause Amplifier circuit has failed Remedy Switch off the power and contact denon
Try unplugging the entire unit and letting it sit for 5 minutes. See if this helps. If not, you need to do a complete reboot, which will cause you to lose your settings, but will probably solve your problem. To do a complete reboot, you will need to hold down two of the front bottons on the front panel. I'm not sure which, so either consult your manual or see other posts here which describe the reboot process for Denons. Hope this helps.
Just had my t753 in bits... sounds like its overheating to me. Check that the fans on the bottom still turn and aren't clogged up with dust. Make sure that it has plenty of ventilation.
hmm, also try unplugging everything and leaving it on and see if it still freezes? ie check you're cabling is ok, there are no shorts from bare speaker wires etc...
Could try resetting it too? (in each case hold the buttons for 5 seconds then release) - Firmware version: hold video 6 and tone control - Reset DSP: video6 + tone defeat - Reset completely: video6 + right source button (this will wipe all settings - hold for 5 seconds, release and then unplug from the wall or turn off with the rear power switch)
The board for your preamp/switch/vol are made as an electric matrix. This means that several signals are coded and sent from the "frontpanel" to the amp itself. A digital signal like this will be hard for someone to measure and understand without a oscilloscope.
My advice is to clean and check all connetions (inside the amp), but mind the hazardous currents inside.