QuestionSorry to trouble you with one more question. If the receiver does have the large amp ic's mounted to the large heat sink as you mentioned, generally, where will the heat sink be (middle, near the speaker inputs, near the volume control knob, near the power supply, etc) and what will the ics look like? For example, will they be round, square, tall, short, etc. I want to take a look inside before I take it to a shop. Thanks again for all your assistance.
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Thanks for the information. I'll take it to a shop. I don't have any experience with electronics repair and am curious to know what the shop should charge me to diagnose the problem before I make the decision whether or not to repair it. If you can tell me what $ range I should expect for a diagnostic, I would appreciate it. Thanks very much.
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I bought a used Yamaha RX-V490 5.1 receiver. It powers on but the audio from any component is very low and filled with pops and static. I can barely hear any audio output. This is the same when the output is through the speakers or the headphone jack. I connected a tape deck to it and plugged the headphones in to the jack on the tape deck. The sound was clear with zero static, but the volume knob on the receiver has no effect on the volume of the music.
I'm wondering if this is a power supply problem that is worth having a technician look at or if it is probably something that would be too expensive to repair. Unfortunately, I don't know the history of the unit (surges, etc.) Any help would be appreciated.
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sounds like an amplification section problem to me, unless something's just set wrong on one or more menus, if it has any. if it indeed is an amp problem and has the large amp ic's mounted to the large heat sink instead of many large 3 legged transistors mounted to heat sink, they're reasonably easy to get and replace. if it uses many transistors for output stage, there's a good possibility that other components are to blame also, and i would recommend letting a pro fix it, as they would have the necessary troubleshooting equipment and service data to fix it. in other words, if it uses the ic output instead of transistors, i'd go ahead and replace it myself as long as i could de-solder the old part and solder in the new. otherwise, it's probably too expensive to have it done....
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you should be able to get an estimate for around $50. after researching your model, it seems like it would be cost effective to fix it.
Answerthere's no telling which side etc. where it will be, but there's no doubt you'll see it, a large finned hunk of aluminum, largest one inside. the ic's, if it has them will be mounted vertically with all the pins on one end, the ic's should be about 2-3 inches wide, 1.5 - 2 inches tall with more than likely 2 screws holding each of them in place. there should be 10-14 pins or legs on each, soldered to main board. if you want, when you open it, if you see something like i've described, you can ask back with the letters and numbers printed on them, and i'll research them and verify whether or not it's them. to replace them, you'll need from radio shack or other electronics store, a small spool of 'de-soldering braid' which is treated so when you place it on soldered joint and apply soldering iron, the solder will be sucked into the braid, making removal of part quite easy, then install new part and solder the legs. you will also need a small tube of 'thermal grease' or 'heat sink compound', which you put a little layer on the metal backside of ic, then mount and solder it. this helps with the heat transfer from the device to the heat sink to prevent overheating and failure. whew!! lol good luck, hopefully it has the ic's, which are easily found, and not expensive at all, compared to discreet transistor type repair. let me know how you make out....
