Topic: Technics SA 8100X

[Rocking-M]

ok you audio gurus. I picked up a technics Receiver.
I've set it up with tape 1 running my XM and tape 2 running the CD but
I cant get my phono to work. On the back are the connectors for the phono
with the choice for semi-conductor or MM. And a switch for whichever I use.

On the front are tape 1, tape 2 and phono or aux switches. Along with other tuner switches
which I've not set up the antenna for as yet. This is a 4 channel beast also.

[tramp]

what year is it?

[Rocking-M]

what year is it?

hey Tramp, it's a 1976 receiver, my turntable is an Onkyo CP 1010A from 1978.

here are the specs on the Receiver,

http://www.classic-audio.com/technics/SA-8100X.html

[Duke McDukiedook]

Odds are you have a moving magnet cartridge on your turntable. Do you know what brand and model it is?
You might have a separate fuse for the phono preamp section you might have to replace.
 

[Rocking-M]

ok, now you know, among other things I'm an audioidiot.
I now have some sound with it set to magnetic, but as you said, it seems to be a
weak signal. With the phono I have to crank the volume up to get a decent sound
output. With any other source the volume is sufficient at about a 2 on the dial.

One thing I also noticed, if I have another source running along with the
phono it will bleed through. I can't find any numbers on my cartridge so I'm
sure I bought one of the cheapest on the shelf the last time I bought one.

Does it sound like the Receiver is preforming as it should?

[Duke McDukiedook]

Sounds like it is a Moving coil cartridge if it is a weak signal, MC's need a lot more amplification than MM's do.
Try the Moving coil input, sounds like you'll have to cut any other sources from playing when you play the turntable.

MC phono amps can be pretty sensitive to any other Rf interference, that's why a lot of people use outboard phono amps.

[Rocking-M]

Outboard phono amps?
Should or could I purchase a seperate pre-amp for the phono and then go into
the receiver input (rca) or is that not right?
How could I set the phono up to use the same speakers but not
the receiver? I have a seperate amp I could just use for the phono.
The Technics sounds great on the radio inputs from the XM and
the CD inputs. I'm really impressed with the receiver but also want
to get the phono working. I just ordered Pink Floyd's "Dark Side of the Moon"
on the new heavy vinyl.

[333]

A preamp between the turntable and receiver is probably the answer.  Is there a ground wire coming from the turntable?  If so, hooking it up might help that bleed over thing.

I did some poking around the web, and it sure does look cool.

[Duke McDukiedook]

Phono preamp, also called a phono stage will boost a MC or MM RIAA signal to normal RCA (2V) input levels.

You could hook it right up to one of your unused RCA input jacks.

Stan is right, could be a grounding problem so if there is a ground wire on your amplifier and one coming from the cartridge, by all means, hook it up.

Just checked on Audioadvisor.com and the cheapest they had was a moving magnet phono stage at $100. Not very cheap at all- and it wouldn't boost your MC cartridge enough.
http://home-audio.audioadvisor.com/search?w=phono+stages

[Rocking-M]

I have the ground wire from the phono hooked up to the grounding screw on the receiver.
There must be a pre-amp built in the unit for the phono but perhaps it's gone bad?
I'll also look into a MM cartridge since I hear they have more output.

[Duke McDukiedook]

Yeah, you could have some leaky caps or something else somewhere on the amp.

Moving coil cartridges are more of an audiophile's cartridge, you'd probably be better off with a decent MM cartridge, they are usually a lot cheaper.

[tramp]

the pre amp in your receiver might be bad
ground all your stuff if there is a ground to do so

[1080]

 I would test the phono inputs by removing the phono cables, then turning the receiver on with the main volume set at about 1/4 or a little than that, then putting in a small jeweller's screwdriver in one of the phono inputs.

You should get a good loud 60Hz buzz on each input phono jack. If you get a loud buzz you may have cartridge problems or phono cable problems. If no loud buzz is heard you may have a switch contact problem or you have a circuit problems.

[Rocking-M]

the pre amp in your receiver might be bad
ground all your stuff if there is a ground to do so

Tramp, I think your right. Here is what I've noticed. I wasn't planning to use the tuner portion of the
Receiver since there is no commercial radio worth listening to, but I decided to give it a try.
The volume is way down on it also. I don't have a diagram but think the tuner and the phono need the preamp.
The rest of the inputs work great. Aux, and tape 1 and 2. So I may have to find a shop to fix the preamp if
it becomes much of an issue or just buy a phono preamp.

[Duke McDukiedook]

Does the sound or interference go away if you turn the sources off that bleed through?
That might be the cheap fix since you are getting some cross-talk/bleed through.

It could just be a leaky/ about to fail diode.

[number13]

Hey Rocking-M -

I repair turntables as part of my business and
deal with table-to-amp problems all the time.
All the advice you have gotten from forum members
so far is good, but you should also check your stylus (needle), it
may just be loose in the cartridge.
Feel free to PM me if you have any turntable questions, I get
them all day long from my customers. 

[Rocking-M]

Hey 13, I'll be asking soon:) I've another cartridge on the way also.