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Some time ago I fell in love with a Beocord 8002 and was able to acquire one, that plays well. however ">>" and "<<" respond only by a few tuns and then stop; I consoled myself with the fact that at least I am able get my cassettes played back. After checking previous threads/posts on this forum I took ample time to stare into the cassette mechanism. Belts are in good condition. Apart from picking up a tiny loose spring, I took several parts apart, cleaned and lubricated where necessary, after this been done:no change in the operation !Before I frustrate myself by trying to locate the position of that tiny spring, first the question:Is there a direct link to possible known electrical failures that you as forum members might have experienced?Secondly, what is the use of that red arrowed spring?
Aad Jansse: red arrow
red arrow
The red arrow spring I've been wondering about for years.I can't for the life of me see what good it's doing.
The other spring;Can we see a photo of the underside of the tapedrive ?
Martin
There are numerous springs inside; do you have records as to how many I should count?So that I can check when I take the drive apart.
It could be the one sitting right behind the large flywheel.Can you tell if there is a spring behind the flywheel ?It should be in the area right behind the stamped "O" in the flywheel metal, just visible in thephoto at the edge of the triangular metal plate.
As you can see I removed the flywheel;next step could be to remove the parts as indicated by the arrows thus showing what's beneath the white wheel. OK?(Any such action will take place after next weekend)
like this.
If you go down there, make sure to note how the three padded brake arms operate. They will all needassistance to end up in the right position when you put it back together.The right side one will even bend if not assisted.Anyway, I have a feeling that the lose spring was a lost part, that was already replaced. It wouldn't be a first.When you press << or >>, does the drive actually wind or rewind before stopping again ?
- and my first thought was that the spring in question was the one from the right reel brake armbut that one seems to be in place. As is the the left one.
Both the ˂˂ and ˃˃ when pressed result in moving the heads towards the cassette and making the spindles turn a little and then: click!, and the heads move back. Is it still possible that it is caused by something "electrical"?
By the way, I found the tapedrive parts displayed in the Beocenter 7000 servicemanual.
Check the solder joints of the large connector that goes to the regulator board. (Bottom plate off).
Out of curiosity: when rewind or forward is pressed, you say it does turn a little before it stops. But does it seem to turn at full speed? Or does it just "tries" to turn?
I had a similar problem last year. Mine was related to the hall sensor. the voltage present was not enough because of a failed small bipolar transistor on the power supply board.
The symptoms looked a lot like yours... except that mine wouldn't play at all. I too would first check for cracked solder joints or bad connections, especially under the big and long white connector. Because if it does turn at full speed before it stops, I might think it's an electrical failure. (based on my small experience)
Guillaume
This thread is interesting to me because I currently have a couple of Beocord units from this line that appear to have a very similar problem. One is a Beocord 8004 and the other is a Beocord 9000. I have gone through both and applied the fix to the clutch assembly (the one that is always cracked) and done all the cleaning and lubricating of the cassette chassis where everything works smoothly.
What I am observing is Fast Forward, Rewind and Play all working fine...for a while. Then they exhibit a similar problem to what Aad Jansse reports on his Beocord 8002. The Fast Forward, Rewind and Play try to engage, but immediately stop. In my case the tape doesn't move in any of the operations. When I tried the decks this morning, they work again. That would seem to indicate a part or joint heating up and failing. It isn't the exact same problem as what Aad is seeing but I am wondering if the area of failure is the same set of components.
I am going to resolder all of those board connections next. I recently had a problem on my Beomaster 8000 where the left channel would go out after a few minutes of play. That turned out to be some bad solder joint(s).
-sonavor
One other note, about the odd spring on the side of the cassette chassis, could that be a spare spring? As mentioned earlier in the thread, the spring attaches between two fixed mounts so it doesn't really do anything. I wonder if it is just mounted there to hold it and it is a spare spring. All of my Beocord 800x and 9000 decks have that extra spring.
Strange indeed: it never occured to me that it was, in fact, useless... The spare part theory make sense. Although if I remember correctlty, these springs do not share the same diameter all over the mech.. So why this one in particular?
The leftover spring is intriguing too...
Looking at the picture of the spare spring again, although it is between two points that don't move during normal use of the tape deck, one side does connect to the bracket for the eject mechanism. That bracket has a slot for fastening it so maybe the spring is used during installation and setup of the eject bracket. Maybe some tool at the factory attached and used that spring to determine the correct setting for the eject mounting bracket. I don't see anything about it in the service manual.
I tested my Beogram 8004 after reflowing the solder joints on the power supply board. The Fast Forward, Rewind and Play buttons all seem to work. I tested making some recordings. Once, when I left the deck recording and came back I noticed it had stopped. The forward and reverse buttons wouldn't work again. However, this time, after changing out tapes and going in and out of standby, the forward and reverse operations resumed. I was able to put the original tape back in and finish the recording. So it still isn't 100%. I am going to look at pulling the clutch mechanism again and changing the position of the Coil Movement setting.
Also clean and relubricate the reel spindles, particularly around their foot at the base metal.They are high, thin steel pins running up through the height of the reel spindles and thespindles occasionally seize.I have also seen one or two cases where the round magnet had separated from the reel spindle and hadsnapped to the base metal.
I think I have success on my Beocord 8004 now. After the reflow of the solder joints on board 2 (power supply board), I had tested a recording and saw that the tape deck stopped once during the recording (about 35 minutes in). I was able to restart and continue recording but decided there had to still be a problem. The Fast Forward, Rewind and Play appeared to work decently but when I opened the cassette deck and rechecked the transport mechanism ,it felt like the engage of the play wasn't as smooth as the Beogram 9000 I just got working. So I disassembled the 8004 transport again, cleaned, re-lubricated and re-adjusted everything. When I got it all put back together, I could tell the Fast Forward, Rewind and Play were working much better. I tested recording and playing back tapes for a couple of hours without any problems.
Thanks for your and the other gentlemens's suggestions. Just a quick summary of my 8002's weak performance:
Play OK, after holding the button 1 @ 1,5 seconds.Rewind It turns a little at full speed, ten stops. Where to find the hall sensor?FF just a click, no movement whatsoever. (spring? or else?)
I will follow up on the aforementioned advice (soldering etc) and will come back to this subject later on.
The hall sensor is a small device placed on the PC board, right above the big flywheel on your photos. It is placed so that it goes inside the mechanism and it's purpose is to detect any varying magnetic field. There's a magnet around one of the reel spindle. When the spindle turn, the hall sensor detect the varying magnetic field. The pulse is send to the microprocessor, so it allows it to count. If it does not detect any movement, the machine assume that it has reached the end of a tape, so it stops...
When the machine plays, what's the reading on the display? does it count accurately, in terms of seconds? If yes, I might think that the sensor is not the problem.
During my failure, when mine was playing (on the extremely rare occasion it managed to play), the counter was displaying numbers as if it was put on fastforward...
Last minute checking my mail (before I will be off-line for a couple of days, too, bad: I have to stay away from my BC), I saw your message: In my and therefore your opinion the sensor is OK: it counts accurately when on Play. (by the way I found the location of the sensor on a scrap motor). Strangely enough now the Rewind turns, irregularly though, when the full cassette reel is on the left side; the display blinks then "cccc"Have a nice weekend,
Aad.
While working on a Beocord 9000 last weekend I went through the service manual again and it does show that odd spring. According to the service manual it has the same part number as the spring that attaches to the eject lever. So it would be available as a spare for that spring I guess.
Since last on this topic, I have spent the last couple of weeks working on the cassette chassis of several Beocord 8004 units and a few Beocord 9000 units. While I can get the units to play and record, my success rate for getting the Fast Forward to operate reliably has not been very good.
I have been able to get one Beocord 8004 cassette chassis able to perform all functions smoothly in two different Beocord 8004 decks...meaning that I can move the cassette chassis assembly from one deck to the other and get the same, successful result. That should mean the electronics in the deck are working okay. I have three Beocord 8004 cassette chassis, that I have disassembled, cleaned, lubricated and re-assembled (with new belts), just like the one "good" one, that fail the Fast Forward test. Rewind and Play work fine. The Fast Forward tries to go but quickly stops. If I remove the cassette but hold down the cassette load button, I can operate the Fast Forward and observe it turning.
On the Beocord 9000 decks, I have two decks fully working and one deck with the same Fast Forward problem as the Beocord 8004 decks.
I have gone through the cassette chassis numerous times now, checking that the parts all easily move and rubber wheels contact and turn. I haven't been able to identify what is different between the "good" cassette chassis and the faulty ones. I have tried changing out the clutch assembly, supply reel and take up reel. So far nothing has worked. New belts have been installed in all of the decks.
The rubber of the "flying idler" develops a hard surface.Sand it away carefully.It will first turn white as the hardened rubber substance is ripped up. You will find black andsoft rubber underneath.
Dillen: The rubber of the "flying idler" develops a hard surface.Sand it away carefully.It will first turn white as the hardened rubber substance is ripped up. You will find black andsoft rubber underneath. Martin
Amazing, I did a quick try on one of the cassette decks and the Fast Forward started working. The rubber material on the "flying idler" didn't appear all that hard...but gently sanding the wheel did wonders to help the contact with the ribbed wheel on the take up reel. Thanks for the information Martin.
Interesting. That's a "fix" for the Nakamachi BX-300 (and other Naks) as well. On the Nak, you can still get the idler tire and replace it.
I am tempted to send one of the wheels to Terry's Rubber Pinch Rollers & Wheels up in Michigan. His minimum charge though it $40 with shipping. It would be interesting to see how it performs.
My 8002 has similar problem, I took the cassettemechanism out of the deck, but how do I get to this idler wheel (the easiest way): from underneath the flywheel?
You will need to remove the belts, clutch assembly, fly-wheel and some metal levers to get to the screws that secure the capstan assembly (where the idler wheel is located).
There are several c-clips you will have to remove. You must be careful those don't fly off somewhere, never to be found again. The large fly-wheel is easy to pull out but you must be careful about a couple of tiny washers that are part of that. There is one metal washer and one nylon washer.
I recommend taking pictures of each step of the dis-assembly and examine each piece for small things like washers and springs. If you run into a problem, let me know and I can dig up some of my pictures.
When you remove your clutch assembly, check the plastic piece for cracks. Here is a link to pictures of one of mine in a Beocord 9000 repair thread. It shows an example of some bad cracks. So far, every Becord 800x and 9000 unit I have looked at (about nine now) has had cracks in that part.
I dug up some of my saved pictures of the Beocord 8004 cassette carriage assembly. It pretty much the same as the Beocord 8002 decks.
This first picture shows the disassembly of the clutch assembly and holding plate of the flywheel.
This picture shows the first belt and the clutch assembly removed. I would advise putting the parts of each assembly into its own plastic bag so you know what goes with what.
Next is the flywheel. Remove the holding plate and you can detach belt 2 and pull out the flywheel. There is a small metal washer on this side of the cassette carriage and a small plastic washer on the other side.
I usually slide the plastic washer onto the removed flywheel along with the metal washer so all of the pieces stay together.
With the clutch and flywheel out of the way you must remove a couple of arms (I called them levers earlier) with a spring, a screw and a couple of c-clips. Tag and bag the parts for each arm separately as the c-clips are not the same size. After the arms are out of the way you can get to the four screws that hold the assembly with the two reels and the idler wheel (flying idler) you are after.
Another step before removing the reel and idler assembly - the spring must be disconnected from the reel and idler assembly mounting post shown in this picture.
Now you are at the disassembly stage where the reel and idler assembly is removed. This picture shows it removed and notes three pressure pads on spring arms you will have to carefully maneuver when re-assembling the reel and idler assembly.
Great help; I will start applying all this as soon as I will be back from a short holiday that is about to begin now. Next wewk i will let you know how I proceed.
Thanks again.
Back from holiday I immediately finished the re-assembling (After receiving the pictures I started already to work on the 8002 and did every thing you suggested during midnight) . Now I find myself staring disappointedly to this machine, there are no parts left, but it does neither Play nor runs Fast forward, nor Rewind. Selecting Play the display shows some activity, that's all.
(I'd better dig up my BC 5000 again to play all my good old cassettes)