Record deck 'hum'

[dark 'n stormy]

So, I've rescued my old Pioneer deck from the loft. It used to get its power from a Pioneer amp that was part of a stacking system but that's long gone. I've bought a 12 volt dc power supply and configured the power connector to be centre negative which is correct for this deck. I've also bought a pre amp from eBay to provide the correct phono power levels. Hooked it all up and connected it to my sound bar and there's an annoying 'hum'.

There's no ground pin on either the deck or the pre amp but I've found a ground point inside the deck and wired that to the case of the pre amp - no difference. I've even tried adding an external earth connection to this lead and if anything, it's worse. The case of the pre amp doesn't appear to be connected to the circuit board anywhere so I suppose connecting ground to the case is a bit pointless. Any ideas ?

 

[StrangewaysHereWeCome]

Have you tried turning it off and on again?

Sorry... my shite dad joke attempts. I'm intrigued to know if anyone here knows though so bumpydoo

 

[chesterbells]

So, I've rescued my old Pioneer deck from the loft. It used to get its power from a Pioneer amp that was part of a stacking system but that's long gone. I've bought a 12 volt dc power supply and configured the power connector to be centre negative which is correct for this deck. I've also bought a pre amp from eBay to provide the correct phono power levels. Hooked it all up and connected it to my sound bar and there's an annoying 'hum'.

There's no ground pin on either the deck or the pre amp but I've found a ground point inside the deck and wired that to the case of the pre amp - no difference. I've even tried adding an external earth connection to this lead and if anything, it's worse. The case of the pre amp doesn't appear to be connected to the circuit board anywhere so I suppose connecting ground to the case is a bit pointless. Any ideas ?

Good luck with that mate, not sure I can help though.

I was going to ask you, as I've done similar, have you had to replace the stylus?
Played some records and found them not playing clearly and needle sliding across the vinyl - just wondered if its the case that the stylus has deteriorated over years of inactivity and just needs replacing - other whether its just my records are f**ked!

 

[dark 'n stormy]

Good luck with that mate, not sure I can help though.

I was going to ask you, as I've done similar, have you had to replace the stylus?
Played some records and found them not playing clearly and needle sliding across the vinyl - just wondered if its the case that the stylus has deteriorated over years of inactivity and just needs replacing - other whether its just my records are f**ked!

I'm just feeling my way around this subject but I think the problem you describe is called 'skid' and it's adjustable.
This is a great site with lots of tips and it's free. http://www.vinylengine.com/

 

[denislawsbackheel]

You need to take an Earth from the tonearm to a ground point. If there isn't an Earth lead with the tone arm cable them use a thin wire, fix one end to the metal on one of the phono sockets on the arm lead and connect the other end under a screw on the amp casework.
Should do it for you.

 

[yeseye]

 

[idahoblues]

Nimrod's your man......he's really old

 

[BimboBob]

http://best-turntables.com/how-to-fix-turntable-hu/


Might help you I hope.

 

[jimharri]

I can see the younger BMers; "Grandad, what's a record deck?"

 

[dark 'n stormy]

Thanks to everyone for suggestions and help. I've finally sorted it.

1. The cheap pre-amp I bought had a ground post but this was not connected to anything. I soldered a wire from the post to a grounding point on the PCB. This improved things but didn't totally cure the problem.

2. My turntable (Pioneer PL-Z81) which was originally part of a stacking system didn't have a grounding wire. It must have got its grounding through its original connection to the 12volt power supplied from the Pioneer stack amplifier (it's now powered by a stand alone 12volt supply). I found a grounding point inside the turntable and ran a wire from this to the ground post on the now modified pre-amp. Result, no more hum.

Now for the old vinyls.