YAMAHA P-220 VINYL RECORDTURNTABLE SPEED PROBLEMS:- HOW CAN I

No, you don't need a preamp if your turntable has a moving-magnet (MM) cartridge, it should work as-is! Happy vinyling =]

See page 27 of the manual:
Yamaha RX V850 User Manual Page 27

Jody, the arm the needle is on, usually adjustable with a dial on the end that can lighten, or put more weight on needle to help it track better on records. Other then that, the belts normally are changed to address slow speed issues. Check the attached links,instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
Jensen JTA 220 Instruction Manual Page 2

http://audio.manualsonline.com/manuals/mfg/jensen/jta220.html

How To Calibrate Your Turntable For the Best Possible Sound

How to Adjust Tracking Force

I suggest you begin by ensuring the turntable and tonearm are as near perfect as you can. The reproduction of sound from vinyl depends first and foremost on the operation of the mechanical components.

The correct stylus fitted correctly with the weight of the tonearm adjusted to the recommended value for the cartridge. There should be no friction vertically or laterally in the arm travel, though some high quality types are fitted with hydraulic dampers.

It is also essential the turntable runs smoothly at a consistent speed. Vinyl purists have all sorts of ways of checking the turntable speed is correct. Most turntables have rubber belts or wheels in the drive from the motor and a defect can ruin the quality of the reproduction.

Owning a turntable for vinyl reproduction is a suitable hobby for a keen amateur mechanic...

Once you are satisfied the mechanical components are in good order and functioning correctly there is only the electronics to consider.
There are two approaches. One involves putting a known good signal into the input of your record player amplifier and the other involves using the output from your turntable into a known good amplifier and speaker system.

These steps involve opening up the case of your record player and making and unmaking various connections.

Good luck!

Pioneer PL X50 Manual Draw Loading Stereo Turntable Vinyl Engine Pioneer PL V70 Manual 2 Speed Belt Drive Turntable Vinyl Engine

PIONEER PL V70 SM Service Manual free download schematics eeprom repair...

Adjust the balance force up. This is a counterweight on the back of the arm. For most needles it is 1-2 grams.

Register (free) at Vinyl Engine and download the service manual. The adjustment you need to do seems fairly simple. You will need a turntable strobe disk to get the the speed right, unless you have perfect pitch.

http://www.vinylengine.com/library/denon/dp-29f.shtml

it will be the turntable speed not exact
quality turntables have bars all around the circumference and when the speed is correct under a fluro light those bars will appear as stationary or using a strobe light set at 50 or 60 cycles a sec
bars going anticlockwise are too fast and moving forward are too slow
quality tables have a small knob or screw to adjust motor speed

Remove the base of the turntable. Look on the main board for a pair of trim pots. They will look something like this

Written eside them will be 33, 45. These are for speed adjustment. Cheers john. Styluscity.com

There is a speed selector directly under the needle arm.

Try moving the arm up to the end of the vinyl, if it does go till the end of the vinyl then try adjusting your counter weights, a penny will do, if it doesn't go till the end of your vinyl then there's a mechanical problem check any obstruction at the botton of your arm.