Pioneer PL-X11Z grounding - UK Vintage Radio Repair and Restoration Discussion Forum

hi_its_me · 14th Aug 2019, 10:55 pm

Hi,

I recovered an old Pioneer PL-X11Z turntable.

The TT was originally part of a full hifi system, with power for the TT supplied through the main hifi deck. The hifi deck got lost somewhere. So I got a DC power adaptor instead to power up the TT.

However, there is a very loud humming noise whenever I turn on the TT.
I checked the circuits, and it turns out that the negative power cable is also the ground. I suppose the original hifi deck dealt with this somehow, but since I am connecting the TT directly to a power adaptor now, I have no idea how to get rid of the humming sound...

Any ideas?

'LIVEWIRE?' · 15th Aug 2019, 8:54 am

What I did once, with a Pioneer deck of a different model, but which was originally part of a system, was to remove the base of the record deck and fit an earth wire to the metal base plate, routed this wire out through the back of the deck, then connected the free end of this wire to the metal chassis of the amplifier with which the deck was to be used. 99% of separate turntables are earthed in this way, and most amplifiers with a magnetic cartridge input have a screw terminal for this purpose near the i/p sockets. Th wire used doesn't have to be anything special-just a length of stranded connecting wire will suffice.

14th Aug 2019, 10:55 pm	#1
hi_its_me Retired Dormant Member Join Date: Aug 2019 Location: London, UK. Posts: 1	Pioneer PL-X11Z grounding Hi, I recovered an old Pioneer PL-X11Z turntable. The TT was originally part of a full hifi system, with power for the TT supplied through the main hifi deck. The hifi deck got lost somewhere. So I got a DC power adaptor instead to power up the TT. However, there is a very loud humming noise whenever I turn on the TT. I checked the circuits, and it turns out that the negative power cable is also the ground. I suppose the original hifi deck dealt with this somehow, but since I am connecting the TT directly to a power adaptor now, I have no idea how to get rid of the humming sound... Any ideas?

15th Aug 2019, 8:54 am	#2
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: Pioneer PL-X11Z grounding What I did once, with a Pioneer deck of a different model, but which was originally part of a system, was to remove the base of the record deck and fit an earth wire to the metal base plate, routed this wire out through the back of the deck, then connected the free end of this wire to the metal chassis of the amplifier with which the deck was to be used. 99% of separate turntables are earthed in this way, and most amplifiers with a magnetic cartridge input have a screw terminal for this purpose near the i/p sockets. Th wire used doesn't have to be anything special-just a length of stranded connecting wire will suffice.