I have a SX-737 which seems fine but for one issue. If you turn the volume down low the right channel drops out. If you slowly turn the volume up the right channel comes back on. This is experienced regardless of what input (fm,phono,aux) is selected. Switches appear functional and there is no noise when using any switches. No distortion is heard in the right channel except for a brief instant when the right channel comes back on (as I am slowly turning up the volume. This is not a speaker issue, I get the same experience using speakers on my headphones.
Odd volume issue
- Thread starter Eroach
- Start date
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- Tags
- sx 737 vintage pioneer volume
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I would suggest that the first step would be to clean the volume pot with Deoxit, along with other pots and switches. You will have to go inside the unit to do this.
See this thread: http://audiokarma.org/forums/index.php?threads/the-idiots-guide-to-using-deoxit-revisited.207005/
You most likely have a dicey connection somewhere. As you increase the voltage with the volume control, this connection closes again.
See this thread: http://audiokarma.org/forums/index.php?threads/the-idiots-guide-to-using-deoxit-revisited.207005/
You most likely have a dicey connection somewhere. As you increase the voltage with the volume control, this connection closes again.
kvining
Active Member
If deoxing doesnt work I'd check for a cold solder joint on the volume pot mounts, not for any particular reason other than I've seen it before on other Pioneer receivers with not exactly the same, but very similar problems. As you turn up the volume the pin heats up and expands enough to cause the cold joint to make contact, when you turn it down it cools and contracts and the connection breaks. If you can get a look at them by pulling the bottom cover, look for one with a tell tale black ring, desolder and resolder.
Protection relay?
The contacts get crusty and like "Spark1's" description, the increased voltage bridges the contacts.
If your savvy, you can jumper the contacts with a wire. See how it runs. First: Make very sure the amps are behaving, all the settings are in spec before short circuiting the relay for troubleshooting purposes.
The contacts get crusty and like "Spark1's" description, the increased voltage bridges the contacts.
If your savvy, you can jumper the contacts with a wire. See how it runs. First: Make very sure the amps are behaving, all the settings are in spec before short circuiting the relay for troubleshooting purposes.
I second the suggestion (zeb beat me to it).
ZebraBlvd
Lunatic Member
Take your time and do a complete (not saying you have not) "Cleaning" of "ALL" controls before looking at an electronics issue. The cleaning of switches\pots can take more than just a one time pass. While cleaning pots is more time intensive than cleaning switches, it is a prerequisite for a lot of the older gear sometimes. Oxidation on pot tabs will cause your problems. And requires a lot more tear down to get them cleaned. I have been fortunate that cleaning the switches resolved my drop-outs of the signal. I have delved into the cleaning of pots, and I do not wish to do it again.
If you do not feel comfortable with a deep clean, hire it out. The 737 is a fine sounding receiver. Had one early on in my quest of audio nirvana. Was not disappointed in its performance. Good luck in finding the cure for yours.
If you do not feel comfortable with a deep clean, hire it out. The 737 is a fine sounding receiver. Had one early on in my quest of audio nirvana. Was not disappointed in its performance. Good luck in finding the cure for yours.
