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Author Topic: My technnics RS-1500, vertically or horizontal? not the same for me ....  (Read 2640 times)

Offline jorsan

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All the afternoon I was trying to deal with a peculiar situation that I honestly do not undertand: if I place the deck lay down, the transport is totally silent and breaks works perfect BUT, if I stand up the unit, sometimes breaks do not work as they should (after FF or REW, sometimes tape is little loose to go to "play" ), and hear some noise in the transport path, do not think is mechanical but the way where the heads are, deal with the tape ...... any comments?, thanks in advance 
« Last Edit: December 31, 2009, 06:11:33 AM by jorsan »

Offline ironbut

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Re: My technnics RS-1500, vertically or horizontal? not the same for me ....
« Reply #1 on: December 31, 2009, 12:21:36 AM »
The brakes on the Technics are it's Achilles' heel. The stock pads just barely do the job. The felt pads are on a lever that's moved upon a drum that forms the body of the motor.
If you grab the reel hold downs or a reel that's attached to the reel table and pull out a little, you'll see that there's a touch of play on the motor axle.
My guess is that when the machines laying down, the drum moves a little farther down (gravity) and the pads are gripping virgin territory. The brake drums have some sort of glossy paint on them but even a gloss finish has some irregularities. Over the years, the felt brake pads have probably polished their normal pathway on the drum so the "fresh" paint of the drum is increasing the braking force.
Whether you believe my latest foray into imaginative diagnosis or not (heck,.. I just half believe it myself!), it comes down to the fact that you need to adjust your brakes or maybe you can just get away with cleaning the drums with alcohol and a q-tip.
 To do this cleaning, take off the back and top of the machine. If you look at the back of the reel motors you'll see the black painted drums. Take a piece of tape and hold down one of the tensioners. This will fool the machine into thinking there's a tape on it (if there is a tape, take it off).Then, put the machine in play. This will turn the reel motors in opposite directions (how they create the tension on the tape) and lift the brake pads off the drum. If you try and clean the drums with the pads contacting the drum, the alcohol will loosen the glue that holds the pads onto the brake lever (then you will have to replace the pads!). Take a q-tip dampened with alcohol and clean the drum as it turns. Then, take a dry one and make sure the drum is dry (let it run for a few more minutes just to be sure). When you're sure it's dry, pull the tape off and let the machine stop. Sometimes a super clean brake will squeak a little but as it gets used, this goes away.
If the brakes chatter, there's probably too much contamination on the pads. Getting at the pads to really work on them requires taking the reel motors off. They're held in by a few screws and the wiring that controls them. It's pretty straight forward to take them off and hang them in the machine while you work on the brakes but dropping one of those screw into the depths of the Technics or breaking one of the several wires that are soldered onto the circuit board that sticks out of the bottom of the motor can really turn a simple operation into a nightmare (not that this has ever happened to me!).
When you see the pads (there's two per side) there's probably some blackish stuff on the leading and trailing ends. This is what makes the brake chatter. I'm not sure what the best way to remove it without loosening the glue is since I've always just replaced the pads.

As far as the noise you're hearing, it may be the tape brushing against the edges of a guide or two.
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Offline jorsan

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Re: My technnics RS-1500, vertically or horizontal? not the same for me ....
« Reply #2 on: December 31, 2009, 08:53:39 AM »
Thanks for your explanation. I follow your directions and some dirt comes from the brakes but not much, now the problem is intermitent, not happens always as before.
« Last Edit: January 01, 2010, 12:04:42 PM by jorsan »