Loud Hum and Low Output in Back left Channel of Sanyo Quad receiver...

[Q-Eight]

So, I scooped a Sanyo DCX 3450 K off ebay for a fair price. I just wanted a secondary unit to plunk along side the PC . Seller said it worked and I took his word. I should have asked did it work in Quad mode. Well, back left channel has a pretty substancial Hum, but there is some audio coming through it. The hum is ONLY in back left, if you pull the BL protection fuse, the other three channels operate normally. So obviously, there's a problem in the amp for back left.

The seller has offered $25 back should I decide to keep the unit or full refund if I send it back. So, he's willing to work things out.

Anybody have any experience with these units? I didn't get home early enough to phone my audio tech friend, but I'm thinking since it still passes sound, it might be repairable.

 

[Quadwreck]

A hum on its own is often a bad capacitor, but with diminished audio, most likely it's a shorted audio output transistor.

 

[Q-Eight]

So, relatively easy to repair?

 

[Quad Linda]

A bad cable could also be the problem. You've probably checked that already. Reverse the rear left and right. If it switches channels, it IS a bad cable.

If you're adept with a soldering iron, it should be a relatively easy repair, assuming it's a cap or transistor.

Perhaps it hums because it doesn't know the words...

 

[scifi]

So, I scooped a Sanyo DCX 3450 K off ebay for a fair price. I just wanted a secondary unit to plunk along side the PC . Seller said it worked and I took his word. I should have asked did it work in Quad mode. Well, back left channel has a pretty substancial Hum, but there is some audio coming through it. The hum is ONLY in back left, if you pull the BL protection fuse, the other three channels operate normally. So obviously, there's a problem in the amp for back left.

The seller has offered $25 back should I decide to keep the unit or full refund if I send it back. So, he's willing to work things out.

Anybody have any experience with these units? I didn't get home early enough to phone my audio tech friend, but I'm thinking since it still passes sound, it might be repairable.

Jiggle the switches and pots while its on to see what happens. Try opening it and spray DeoxIt in the switches and pots (make sure its off and unplugged).

 

[leevitalone1]

A bad cable could also be the problem. You've probably checked that already. Reverse the rear left and right. If it switches channels, it IS a bad cable.

If you're adept with a soldering iron, it should be a relatively easy repair, assuming it's a cap or transistor.

Perhaps it hums because it doesn't know the words...

Bad cable is a more likley issue.I had an issue with a channel that went low. It was a bad line. It was loose in the port. swapped it out and it was ok.

 

[Q-Eight]

No, it's not a cable issue or a pot problem - matter of factly, the pots on it are nice and quiet! Not a hint of static anywhere. I did notice that in 2-channel mode, there is a very, very slight hum in the left channel, but when in 4 channel mode it's in back left only. It'll actually hum with no signal. Set to Aux Input, don't play anything and it'll hum. It's also there on speaker output and on the headphone output. Got a local guy that's been given the thumbs up by a few people. Gonna call him on monday and see what he says.