Teac X-1000r R2R Adventures

SCompRacer

Cue the bells and whistles...most Teac guys claim the X1000r was made much better than the X2000r. Black ones are way cool but the black VU meters are harder to see.



I’m getting braver. Teac X-1000r. Near excellent condition, heads have some wear but far from wore out. One weakness of these decks is the capstan motor, EM1446. Teac went to DC motors in the X series. That means brushes and commutators. When the brushes get thin, you may lose brush tension and the brush doesn’t touch the commutator. It also means if your belt gets gooey and the capstan motor freezes, the motor burns out. One of my fav ebay ads read “Teac X1000 purchased in estate sale. We plugged it in and pressed play and smoke came out of vents….still in excellent condition but needs work.”

Pioneer 901/909 used the same motor, but Pioneer added a sensing circuit that protects the motor in a high amperage condition. Teac may have said, we saved a few bucks not adding that circuitry, so you just may have to buy yourself a motor.

The new capstan motor supply was exhausted ~ 2021. Only used are available for big money, ~ $250-$350+. Most being in the ‘like a box of chocolates, you never know what you're gonna get’ category. (Although one reputable seller opens them up to show brushes and provides scope pattern of tachometer). He is in the higher price range but less of a gamble.

If you’re handy, and brave, unstable, you can get brushes that are close in size, file the ends flat and conductive epoxy them in. Size is ~ 3mm x 3mm x 4mm.



Did I mention these were small motors?



The old paper clip trick. If you pull armature out without spreading brushes, you will bend/destroy the brushes/holders. Maybe the plastic nubs too. You must remove brush end and armature in one piece.



One brush little thinner than the other. The bottom is thinner, taper wear.



Trying an acetone soak but that is cured epoxy.





Take a look at the reel motor brushes. They are like new. The only reason I can think of for the worn capstan brushes is 1) motor was replaced. 2) Leaving the unit powered on, not playing a tape but the tape tension is holding the R and L tension arms up. With tension arms up, the capstan motor runs, even when tape not playing. Add some slack in tape, tension arms fall, capstan motor does not run.




Oh look, two more to do! Me and two lucky? friends are going be the three Teac amigos.

SCompRacer

Brushes and small non-polar caps ordered for motors.

It's always interesting to see what went on inside used gear that saw service.

Power set to Japan, 100V instead of 117.



Belt replacement requires removing capstan motor bracket. They missed getting the timer switch mounting nubs in the top of capstan motor bracket. The mounting screws above it are not accessible with circuit boards mounted in place on rear of deck.



This resulted in breaking one of the two timer switches.



It's best to remove the entire assembly to properly clean and lube the pinch roller linkage. Easier to clean all the tape path and heads too. The head assembly is mounted on fixed posts so the head height/azimuth adjustments remain unmolested.



You can also remove any goo belt remnants obscured by components left installed. This stuff is like the gift that keeps on giving. Get it on your fingers or step on it and you'll leave a mark on everything you touch or every step you take.



Yeah, I mark everything even if it's obvious the R and L pinch roller arms are not interchangeable. ....



A missing washer. You can tell by the grease mark one was missing. I'll be searching to make sure it isn't inside somewhere.



This is the solenoid actuator linkage at rear between the capstan flywheels. Hard to access that installed. Sharp eyes will notice the R and L capstan flywheels are different, so I take pictures, mark everything. I have not reached the familiarity breeds contempt stage with the X-1000r yet.

SCompRacer

Had an issue with the fast rewind switch, had to wiggle it to work. Removed front panel, seemed easiet with everything else off it.



Common issues I'm told. Simple easily obtainable momentary contact switches. Beats a $75 used panel.




Look what I found. The missing pinch roller linkage washer.

SeleniumFalcon

"..every step you take." Isn't that a Police song? Nice work! A Teac master mechanic!

SCompRacer

Yes, I was channeling some Police there!

You are kind of responsible for this madness.

Another common issue is a spring in the left tape guide roller gets mangled and/or broken. The spring creates a path to ground when a metal sensing foil completes the circuit between the sensing post and roller guide. That triggers reverse play mode, the "r" in X-1000r.



This is what it should look like.



Two of the three decks had mangled springs. I straightened them. They are sold with the roller on ebay for $25 and up, typically with bent spring.

The manual shows the loop around the axle but some argue it rests against it. When you remove the roller retainer, I think the spring snaps off the axle and ends up touching the edge of axle. The nylon washer goes over the spring, then the roller retainer. At 2 o'clock is the sensing post.

What you don't want is the spring getting caught between the retainer and axle. All you have to do to confirm correct assembly is spin the tape guide roller. No spin, fix it.

agfrost

You've been busy, Rich!

SCompRacer

My brain was turning to mush so I figured better start using it again.

While waiting for parts I decided to lap the heads. They had some wear but were in lapping range. If you got deep pockets you can try for some NOS. New record heads are around $80, while play heads are $200-250. The 1000r records and plays in reverse so that's two of each. Used can be in worse condition than the ones you have.

Lapping requires a steady pressure while dragging and turning the head on sandpaper on a flat surface to remove material along the entire contour. A chunk of wood with an old broom handle across a sink to give some angle. Running water is best to flush sanding debris off paper. I didn't have any glass so I used a chunk of granite.

400, 800 and 1500 wet/dry paper is used. Take only enough material to make the tape groove disappear. All four took less than an hour. I check progress often with a lighted magnifier.

I was free handing but remembered this angle aluminum I had. A little grease on it helps lubricate the thick mounting side of head while dragging against it.




Heads slightly worn. Would still play OK but when calibrating and adjusting azimuth, you want a smooth surface for the tape.



The record head on left is finish lapped and just needs polishing. You can see it still has a contour, no flat spots. The one on right is up next. I didn't have any finish lapping cloth so used some Mothers Aluminum polish instead.



Since the heads were removed from their mounting brackets, the height and azimuth screws were untouched. Head align looks pretty good. Before assembly, I'll attach it with screws and ensure the coarse adjustment is all good.

SCompRacer

Still await brushes. I cobbled together a way to remove the old brushes while protecting the fragile strap it is attached to.

A piece of scrap lumber. Drill hole size of brush. Cut a washer up and smooth rough edges. Drill hole in washer for screw. Use a shim under washer thickness of strap.



A lighted magnifier helps. I soaked the assembly in acetone for a couple days. It was well cured epoxy and the acetone didn't seem to help at first but it may have softened it. I carefully scaped epoxy with a sharp Exacto knife.




No collateral damage!

SeleniumFalcon

That's really clever, Rich!

SCompRacer

Thanks Ken!

More progress. 1uf 50v Bipolar caps arrived for the reel motors. They were only 20% out while the capstan was 40% out spec. Inductors tested good. Good brushes, sealed ball bearings smooth, all good.



Cleaned up commutators, reassembled both reel motors and tested. 12v .07 amp no load is good.



A little finger pressure and amps increase. These little motors have some torque. I had it a little over an amp and got a hot spot on the finger from the motor shaft.



Got the tactile switches. I provided part number to maybe help someone else. IMO it is risky purchasing a used control panel that could have same issue. The momentary switches were $.12 each, $1.80 for fifteen. A used panel can set you back $68. Yes, it's a process but the Hakko desoldering gun made it easy. I ordered 45 in case the other two decks need them.



A little smaller footprint but height and terminal spacing are correct.



One new switch installed by the 4" mark. If too high switches will be held in ON. The old ones measured between 4.75 and 5mm tall off PCB. I measured 5.56mm from switch actuator to PCB.



All in. Double checked all terminals that had a trace were soldered in and all switches against PCB. Not all terminals are soldered and the replacements do not have a fifth locating leg. Some of the old switches had pads for the locating tabs and were soldered. I wondered if it was for ESD ground, but the pads have no continuity to ground. No LED's suffered collateral damage.



I tested all these switches before installing and after installed. Clipped ohm meter to power side of switches and pushed every button to ensure full open and good closed numbers. Some buttons have slightly longer plungers and less clearance to switches than others. Some with only .002" clearance.



Panel in place. Leave the control panel mounting screws loose when fitting face plate.



I received the used timer switches and replaced those. They were on a broken PCB so got them cheap.



Face plate on, getting closer. Await brushes and inductors for capstan motor.

SCompRacer

Brush time. I learned there are a few different grades of brushes. The ones I got say carbon, but they look more like carbon graphite. A brush company engineer said they are slightly softer than carbon but will work and should last as long. We'll see.

I had ordered some brushes near the exact size, 3x3 mm. They were longer but easily trimmed to 4mm length. But it was a leaded brush. I was thinking how far those leads may extend into brush. We don't want harder wire eating up the commutator as brush wears.

I found an unleaded brush, but it was 4x4mm and needed to be trimmed down. While one could do some filing/sanding by hand, I wanted a way to achieve a more precision result. So, I cobbled again.



Two 1/8" (3.18mm) drill bits fastened down to a chunk of wood with a screw and nut. The screw allows repositioning the bits to get a snug fit on the width of brush. A file is used. Drill shanks are hard, the file just removes brush material. The .18mm can disappear dragging it over some fine sandpaper. I don't want to deviate from the OEM brush size.

Second station, two more 1/8" (3.18mm) drill bits set to hold the 3.18mm width tight. File down to 3.18, now I have a square brush.

Third station. Two 3/32" (2.33mm) drill bits. Two concrete nails. A 1/16" bit used as stop. This files some relief on each side of brush to fit in the small slot in brush holder.





This brush will get trimmed down. The strap can only stretch so far before the strap or plastic posts it's wraps around, gives.



Conductive epoxy is pricey but they do sell it in small packets for $13 on Amazon.





24 hours cure time and they we'll see if it holds. My old eyes held out long enough working through lighted magnifier to apply some conductive epoxy without making too much of a mess.

SCompRacer

It lives! Gonna run it, break in brushes. When inductors get here, I'll pop it apart and replace them, clean out any brush dust.

SCompRacer

The owner of this deck has been sitting on two pairs of Teac CA (Cobalt Amorphous) record/playback heads (found in the X-2000r) and asked for them to be installed instead of the Permalloy. They standout due to orange epoxy being used instead of black.



Teac said their CA, Cobalt Amorphous head, has twice as many segments as a regular Permalloy head. The advantages are significantly smaller eddy current losses making it easier on the recording/playback amplifier. They also claimed better operation in the HF range.

When swapping heads, head alignment needs to be checked and adjusted. Next up, the old clear leader trick, improved. I cut a length of clear leader tape and attached a short piece of rubber band to the loose ends. This keeps the tape tensioned and leaves my hands free to turn screws.



The tape was routed under the capstans in order to wrap the tape around the record heads for easier adjusting.



It's easy to set height, that is edge of tape position to head cores, but harder to ensure the head is square to the tape and head plate, especially with head shields. This is all I will show as my setup is very Rube Goldberg like. Basically, a square that has been checked with another square has been secured to a flat surface that had been checked with a straight edge.

The head plate is secured against the square, so the head plate is 90 degrees to the flat surface. A dial indicator is used to adjust head position. That is front and back of head are equal distance off the flat surface. It sure looked pretty good viewed from different angles. Any adjustment here means the clear leader tape must be installed and height checked again. The shields were added after this adjustment.



Getting closer to hope it still works...and calibration.