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Need Help With Turntable...again :(

Posted: Thu Nov 13, 2008 9:41 pm
by MrCrowley
Okay, after my last turntable kicked the bucket, I bought another one...again I was told it worked.

The trader wont reply to emails and they live in the South Island (I'm in the North), so there's not much I can do but give bad feedback.

Anyway, the turntable is a Pioneer PL 5 and looks like this:
Image

Everything works flawlessly...except for the part where there's no sound coming out of my speakers :lol:

I took it apart, rewired the RCA plugs (just the plugs, not the wire that goes into the turntable as it's too difficult to access) and tried two different pre-amps. My main amp being a Harman/Kardon PM625. It can play turntables and the Phono setting (for turntables) works fine.

I'm wondering what I should try next, the stylus works fine and appears to be wired correctly. Should I just take it in to get fixed? I paid $40 for it and I would prefer not to waste anymore on it, but if it's the only option...

Any help appreciated. :)

Posted: Thu Nov 13, 2008 10:30 pm
by starman
If you have proven your amp and preamp sections are working, there really isn't much else to it. The phono pickup is a passive device, sort of like a microphone and it either puts out the signal or it doesn't and it's also unlikely both channels would be bad. Make sure you're plugged in to the correct input (RIAA equalized)...sounds like you already have that covered.

It is probably something dumb like some input switch has been broken or is in the wrong position for phono. If you had another amp that you could plug the RCA jacks into, it might help you narrow things down a bit.

Otherwise, if you run into your skill limit, it's probably time to just haul it in the electronics nerd and let him run it down for you.

Posted: Thu Nov 13, 2008 10:39 pm
by MrCrowley
It is probably something dumb like some input switch has been broken or is in the wrong position for phono. If you had another amp that you could plug the RCA jacks into, it might help you narrow things down a bit.
Yeah I tested it with a Technics amp last night, nothing.

I get a hum when I turn both amps on to Phono, so it must be in the turntable. The 4 wires on the stylus/cartridge are all connected to the right slots as well.

Posted: Fri Nov 14, 2008 12:01 am
by starman
If you're hearing a hum, it's likely the ground and signal wires may be cris-crossed. Not sure how that could happen if you believe the wires are all plugged in the right connections on the cartridge. Still, go over it again.

There's really nothing that can go wrong in there...no electronics, nothing, just a straight wire to the cartridge. That's what would push me to find a wiring problem at the cartridge.

Unplug the cartridge and see if you still hear the hum or if it changes character.

Posted: Fri Nov 14, 2008 12:31 am
by MrCrowley
The hum can only be heard when my amp is at about 75% volume on the volume knob...I usually don't go above about 20-25% because that's pretty loud.

One wire was in the wrong slot when I referenced the manual, no change in the hum except for when I put my fingers close to the wires it increases. Does the same on my other turntable.

I'll go over everything on the turntable tomorrow, take it apart again, follow all the wires etc. Hopefully i'll find something.

Posted: Fri Nov 14, 2008 12:40 pm
by jimmy101
Remove the cartridge. Get a 1.5V battery. Connect the turntable to the amp and turn the volume way down. Touch the battery contacts to the various wires where the cartridge connects. Any sound out'a the AMP? If there is, the problem may be the catridge. If there isn't, the problem is in the turntable or AMP somewhere.

Do the same test on the amp, touch the battery contacts to the phono plug. You should get clicking noises. Another test for the amp is to just short the contacts on the RCA cable with your finger. You should get either a significant increase, or a decrease, in the hum the AMP makes at high gain.

Posted: Fri Nov 14, 2008 7:30 pm
by MrCrowley
Hahah you wouldn't believe it. Turns out the screw holding the cartridge on to the arm was missing, no biggy I thought. Apparently this screw needs to have contact with the arm, so I chuck a screw in there and it starts to work. It's a bit fuzzy at the moment so i'll try adjusting a few things.

Edit:

Hmm, still pretty damn fuzzy. Playing about with the RCA cables on the phono plugs or the ground wire, seem to have no effect on the grainy distortion coming out my speakers :lol:
I can make out the song, but it's pretty fuzzy.
It's not the record or the wires connecting to the cartridge. So i'm thinking the stylus has had it.

It could be there's too much weight on the arm, but adjusting the weight has little effect also. The only thing is i'd prefer not to spend $30 on a new stylus if I don't need one or not.

Posted: Fri Nov 14, 2008 10:47 pm
by starman
The pickup may need to be aligned. If it's hitting at an angle you'll hear crap. Also, are you plugged into real RIAA phono inputs on your amp?

Posted: Fri Nov 14, 2008 11:17 pm
by MrCrowley
starman wrote:The pickup may need to be aligned. If it's hitting at an angle you'll hear crap. Also, are you plugged into real RIAA phono inputs on your amp?
What is the pickup and how can you realign it?

I believe so, the amp manual says the phono slots i've got it plugged into are for turntables. Does the answer your question?

Posted: Sat Nov 15, 2008 11:00 am
by jimmy101
Does the needle catridge have one or two needles? Some of the really old cartridges had two needles; one for 33.3 and 45 and another for 78 (talking really old here), the two were mounted on the same arm and swapped by flipping a lever.

Get a magnifying glass and look at the needle. Is there one there and is it still pointy? Does it look like the needle and its carrier are OK? No bends in the needle carrier that would put the needle out of alignment? Sometimes you can replace just the needle instead of the entire cartridge.

Check the the weight of the arm at the needle and any anti-skating mechanism. If you lift the arm with the finger handle and gently bounce it up and down on your finger tip there shouldn't be any tendency for the arm to swing towards the center or the outside of the record (that's what the anti-skating adjustment is for).

Posted: Sat Nov 15, 2008 11:48 am
by starman
MrCrowley wrote:
starman wrote:The pickup may need to be aligned. If it's hitting at an angle you'll hear crap. Also, are you plugged into real RIAA phono inputs on your amp?
What is the pickup and how can you realign it?
pickup = cartridge...it really depends on your cartridge and its mounting mechanism on the arm. The needle has to ride "squarely" and flat in the groove to obtain hifi sound. If it is sitting at an angle or tipped to far forward or backward you'll get some ugly distortion.

In my days of playing phono records, these things pretty much took care of themselves. Balance the tone arm for the correct weight and skate, check the turntable speed strobe and you're good to go. If I were getting the ugliness you describe at this point I would be looking at the needle and cartridge very closely.

Posted: Sat Nov 15, 2008 2:16 pm
by MrCrowley
I'll get a picture up later on. It looks bent or out of alingment to me, but then again I don't know a helluva lot 'bout turntables.

Jimmy101, thanks for the clarification on anti-skating by the way. The manual just says how to change it, not what it actually does.

I was looking at a replacement stylus on www.styli.co.nz. A new one will cost me $175NZD which is about $98USD. :shock:

Posted: Sat Nov 15, 2008 6:34 pm
by jimmy101
MrCrowley wrote:I'll get a picture up later on. It looks bent or out of alingment to me, but then again I don't know a helluva lot 'bout turntables.

Jimmy101, thanks for the clarification on anti-skating by the way. The manual just says how to change it, not what it actually does.

I was looking at a replacement stylus on www.styli.co.nz. A new one will cost me $175NZD which is about $98USD. :shock:
Most decent cartridges have replacable needles. Been ages since I saw needles, RadioShack used to have'm. IIRC a new needle might be about $10.

Posted: Sat Nov 15, 2008 6:54 pm
by MrCrowley
Thanks, i'll have a look into it.

Here's some pictures, my camera ran out of batteries so I used my phone and a pocket knife magnifying glass :P

Posted: Sat Nov 15, 2008 7:26 pm
by jitup
IF your amp has a phono inputs built in, you may not need the preamp, If you don't need the preamp and you have it hooked up the singnal will be to high for the amo and one of two things will happen, first and common with cheap amps is that you will get super bad sound with emense clipping, or second, this is more common with high quality amps, a level circuit will trip and will cause a hum/ buzz, or no sound at all.
If you try with out the pre amp and it still does not work, the turn table is broken.