Technics decks maintenance and general Dj gear repair links


There's several instructions like this on the net, all differing according to the author(s). This is as far as possible based on the instructions in the manuals. It should at least be interesting reading to any deck owner, especially the part on general setup. For the mods and hacks, if you're at all unsure about what you're doing, don't! Decks are too expensive to learn on, find another subject for your first time bloopers.


45 adapter: the standard included with the Technics is for straight playback. The big hole in the 7" easily slips under the adapter when working the small vinyls. If not, the adapter may stick to the hole. It generally requires more attention than normal records and is a bother. Conical adapters promise throw on/off ease of use. Some suggests gluing up a 12" with guides to hold the 7" firmly in place. There's some adapters out there that clips into the hole(picture), if you find one, you're in luck. They're very handy, usually thrown in for free with an old 7" and gives great scratchability!

On/off switch: Breaks off and goes off at the wrong time when hands drags it off while backspinning. New models have a better solution. Light is four 5mm red LED's, replaceable with any 5mm LED.

Start/stop switch
: Startup time is specified to 0.7 seconds from standstill to 33-1/3 rpm. Stop/brake force is adjustable on the vr201 trimpot, located on the motor PCB under the platter(picture). It's normal for the stop time to vary a bit no matter how it's adjusted.

If it's consequently too little braking force or the platter goes backwards instead of stopping, it's time to adjust it. Turn of the table and disconnect the power cable if you want to be fail-safe. It's important to never turn on a deck with the platter removed, it can be destroyed. With the table off, remove the 2 kg platter. Remove the five screws holding the plastic cover(picture), locate the trimpot and make a tiny adjustment. Replace platter, turn on, test brake force with slipmat and a regular vinyl, turn off and make another adjustment. Repeat until you're satisfied. Manual says it should stop within 90-120' angle (mk2 manual) or 30~210' angle (m3d manual) after pressing the stop button. If you're very careful you can access the trimpot through the holes in the platter, making small adjustments a breeze without the hassle of removing the platter.

33/45 selector switches: Two 3mm red LED's replaceable with any 3mm LED.

Pop-up target light: Incandescent lightbulb burns out, see replacement instructions. Can also be replaced once and forever with a LED and a resistor.

Pitch fader: A double circuit, one part is the normal fader and one is the quartz lock and center click. At the center click a small spring loaded ball slots into a hole in the fader, locking it physically in place. At the same time two tracks in the fader short out. Those tracks make the zero point a region where the fader is no longer active and the clock runs at precise quartz lock no matter how bad the rest of the fader can be. The LED is a 2x5mm square that can be replaced when you find the right size in your desired color. It's got two adjustments. See the pitch center click removal instructions for general access and maintenance.

The zero point can be set by tweaking vr302 on the pitch fader PCB(picture). If it's wrong it'll give a double zero spot on the fader, one on the fader it self and one on the quartz lock center click. If you remove the zero region by removing the wires from the quartz lock this will never happen but it will probably still need adjustment.

The pitch gain control adjustment, vr301 on the
motor PCB(picture) governs the range of the pitch fader. Set the table at 6% and adjust until the dots on the platter is still at 6%, then do 3%, -3% and so on until you settle on a desired compromise between the results you'll get. Or wack it open for bigger pitch range, an increase to 10-12% may be had.


Platter: 2kg of stable rotating matter moving by the virtue of an indestructible magnetic force field. In other words, an electric motor capable of sustaining just about any abuse you can throw at it. The only moving part is the spindle bearing in the center. This needs lube, three drops of light oil every 2000 hours according to the manual. See the pitch center click removal guide. Lift it off using the holes in the platter. If it doesn't work, very carefully try to tap the center while someone lifts on the platter. Let me repeat, if you're at all unsure about what you're doing, don't. Under the platter is the 110/230VAC mains switch and a plastic cover with five screws that hides the main motor PCB.


Tone arm and pick up: probably the subject of most confusion. There's a lot of personal opinions that may very well be funded on good experience especially for particular situations like heavy scratching. This I'll leave to you to explore if you care and dare. What I'll present here is the way of doings things correct according to the manufacturers. Technical information like height and recommended stylus pressure for the needle/cartridge are usually found in the manual or on the manufacturers website. Needles have a tendency to bed into a given position, so these adjustments are best done on a fresh needle. To make it as relevant to the real world as possible use the height adjustment on the rubber feet and a level tool to set the decks straight. A burst of canned air directed on the tonearm every once in a while will keep it dust free and good looking.

Tone arm height: adjustable by turning the big ring on the base of the tone arm. Unlock the height adjustment by twisting the small lock on the upper right hand side clockwise. The scale is graded to suit the height of the cartridge, adjustable from 15mm to 21mm. Zero on the scale is for 15mm pickups, up to six on the scale for 21mm. Example; Shure m44-7 are 15.9mm so the scale should be set at 0.9.

Anti-skating: is provided in the tonearm to battle the physical force that makes the S shaped tone arm connected to the rotating disc, going in the direction it goes, want to go inwards. If you reverse the direction of the disc you actually need exactly the same sort of counterbalance system, working the opposite way. For normal listening, Technics recommend it to be set at the same value as the stulys pressure/weight. Most scales are unfortunately way off. To get a coarse manual adjustment, find a record with a blank side so the needle can float freely when it plays. Adjust the anti-skate so the needle stays in the outer parts of the record. For scratching and general back-cueing mixing where the needle goes both ways, leave it at zero. The best and only way to set it properly is to play a record with shrill treble, like a viola recording, and adjust the anti-skate for equal treble distortion in both channels. The distortion will vary from channel to channel as the skating or anti-skating puts more pressure on one of the vinyl groove sidewalls than the other.

The weight scale: is useless unless it is balanced. Different pick ups and headshells have different weight, so it must be be set at proper zero before it can be used. Rotate the weight backwards until the arm floats parallel to the record surface. Holding the weight still, turn the number dial so the zero aligns with the dent in the tonearm. Set the weight according to the needle manufacturers recommendations. Don't reverse the weight or add coins, if you need that much pressure something is very wrong either with the setup or your technique. Watch out for the tiny extra weight that can be screwed into the end of the tonearm. It'll make adjustment with normal needles impossible.

Tone arm bearings: adjustable on the four screws making the up/down and back/forth movements of the arm possible. Take hold of the arm and wiggle it, try to see if there's free play in the bearing. Loosen the outer locking ring and very carefully tighten the tiny screw. Locking the outer screw again will give more torque on the bearing so it must be set slightly looser than it should be before tightening up. Be patient and do not over torque! If you set the bearing to tight they will be damaged and the only solution is a new bearing in a new tonearm. This is an easy way to ruin decks, please do not touch them unless absolutely necessary and do use utmost caution if you must. Give it a tiny bit of oil while you're at it but do not loosen the screws more than a tiny fraction. Careful is the word around here.

Cartridge mount: The screw lock on the end of the tonearm that connects the cartridge to the audio wires inside the tonearm. Needs occasional cleaning, but please do not lick it! It can be a handy last resort in the battle field but leads to accelerated corrosion. The contacts should be cleaned and deoxidized with some technical spirit or general cleaning alcohol. Use a Q-tip to reach the inner contacts.

The cartridge: should be mounted so the cartridge is almost parallel to the headshell, see note below. The overhang is set to 52mm. That's the distance from the needle tip to the headshell mount. New decks are supplied with a strangle looking white tool(picture), an overhang gauge that makes this adjustment easier. Screw off the headshell and put it into the round hole in the tool. The needle should be aligned to the small indent in front of the gauge. Dig out a ruler if you don't have the device. Here's the note: If the cartridge is totally parallel to the headshell it'll be slightly off when you put it in the gauge(picture). A best fit compromise to compensate for the changing angle of the needle as it travels in an arc on the record. Thanx to the nice explanation at turntabletech for the tip. Straight tone arms leaves the needle at 23' angle outwards from the records. To emulate this set the cartridge at 23' outwards in the headshell. This will lead to special wear on the records and they will probably be shaped by the uneven wear after a while. A small article on the shortcommings of straight tone arms can be found here.

The Needle: is a mechanical device and needs break in time before actual usage. A brand new needle will sound harsher and skip more than it'll do in a few hours use. There's probably as many ways to set the new needle up for use as there's Dj's. Here's the routine that seems to be the most accepted: put the needle on the record, with the turntable power turned off, leaving it there while you sleep through the night. As simple as that! Give it a few hours of easy playing before you start on the wild scratching.


Audio and grounding cables: needs replacement sooner or later. Instructions with some suggestions to make them last longer here. If using oversized cables you'll have to carve room in the cable strain relief to make them fit.



A short selection of useful links:

Djbattle is a good source for a lot of info, if you read Swedish..

There's some info at hyperreal, most noticeably the classic 1200 FAQ that appears just about everywhere in slightly modified versions and a general Dj tutorial.

Another 
FAQ here.

Some stores that fixes and upgrades turntables, a lot of info and some ideas of the possibilities: 1200s Turntabletech.
and Kabusa.

General cleaning instructions for plastic based faders here.

A quick look inside the Penny & Giles and the Vestax PVC faders.

Some pictures of vinyl grooves at Recordtech

Pictures of the vinyl manufacturing process, cutterheads and more at Aardvark

The reverse mod's are easily available on the web as kits with instructions included in the package. Watch out for the price as this is wildly variable!




Use the search engines and know how to use them. Google for starters.


To BTM-muzak
 

(C) Andreas Nordenstam - April 2004 - last updated Feb 2011
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