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Phono connection for pioneer sx34b

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Hello everyone, I got a pioneer sx34b receiver recently, everything seems to work fine except when I switch the nob to phono without any source connected, a loud buzz came on. What can I do to get rid of this buzzing noise. I want to connect my Philip 212 with it. Thks in advance.
Try placing shorting plugs in the phono I/Ps. If that eliminates the buzz, you are already good to go. Remove the shorting plugs and connect the TT up.

I've uploaded a schematic of sorts. You'll have to dig around the WWW with google to get a version with more detail.


  • Pioneer SX-34B Schematic.jpg
    Pioneer SX-34B Schematic.jpg
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Thank you Jeff and Eli... For the quick response!
But here the thing, I have try several of plug shortening techniques but the hum still remain. What causes this? All other source inputs on the sx34b work good except for the phono input. While I am suspecting a bad tube or ic from the receiver, is there other way to troubleshoot the phono input ?
Not shortening, shorting. Get an inexpensive pair of RCA plugs and solder a short length of wire between the center pin and the outer shell. Install the shorting plugs in the phono I/Ps and see what happens. You must remember that the phono preamp section is designed to work with mV. level signals. You could be picking up EMI from the environment. This kind of trouble also occurs with SS phono preamp circuits.
Hi Eli... Yes I inserted the shorting pin between the L/R phono input of the reciever, but the hum still there and its on both channel.
Thks again for ur both quick reply.
Not shorting pin, but shorting plug. Using a shorting pin you've connected the L and R inputs together, that's not what you want to do. A shorting plug shorts (shunts) the individual L and R inputs to ground.
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