Classic vz-2000 problem. Please help
Posted 07 December 2019 - 08:03 PM
I have fully disassembled my vz-2000. It is showing the classic sign of barley any sound and slight buzzing. I have cleaned everything under the sun but the problem persists. Before I go and rip up the balance slider I am trying to work the record/play button on the cassette. I am finding that all the buttons on the cassette side of the unit press down freely and smoothly. But the record button (which looks like it also presses the play button down at the same time) binds up. With out another unit to compare to does the record button actually get pressed and go down all the way and stay untill “stop” is pushed.
I have the unit open but have not removed the cassette side fully from the unit. I am just examining the fiction of it all. If I am correct in that fact that when the record button is pressed it also pushes down the play button so I push the play button down first and see the internal movements and then try to press the record button down to watch it’s internal movements and see where if anything it’s getting held up. No luck so far. And how could the cassette bar interfere with sound when I’m on the radio setting for example. I can still get a radio station sound all tho it is very very faint.
And question number two. I am spent hours on trying to research the balance slider situation and can’t find any good tutorials. A guy did do a repair where he bent the metal up then cut it on either side so he could just slide out the knob with out having to solder anything back. He just reattached the metal after putting the slider back in with in weld. I would be comfortable doing this but I have no idea what to look for when I do get the slider out! (No info just talk of pins or brushes being to high....... and I don’t comprehend this all)
I’ve reached the end of my comfort level with diagnosing this as my patience wears and I end up “forcing things”. Ie tried to take up watch repair and figured I don’t have what it takes for “micro” repairs. Ended up butchering every watch I tried to find by “ramming” things in. I’m located in Victoria,BC (Canada). There is an old timer here that owns a shop that I might trust to work on it if all else fails.
One last thing. All those function buttons and working them with cleaner and pushing them over for ten minutes how does this help. I mean in I’m able to push them and they switch functions then arnt they working and not interfering with my issues. Sorry for my ignorance and if you’ve read thru this all your time is appricated.
Posted 07 December 2019 - 08:30 PM
There is a lockout lever that prevents the record button from depressing unless that lever is pushed up. Cassettes have tabs on the corners that can be removed if you want to prevent the tape from being erased. With the tab removed, the record-lockout lever sits in that pocket preventing the record button from being actuated. If you manually press that lever up simulating the presence of a recordable tape, you can then depress the record button.
I have no idea what you mean with the slider modification or what you are asking. Furthermore, there won't be any tutorials on how to modify a slider by stripping out the innards and replacing the empty shell which is what it sounds like you are saying. It may be best if you post images so people can see what you are talking about but if this is beyond your abilities, you should just have a professional see what they can do for you. The VZ2000 is no boombox for a novice to start learning on, it's one of the most complicated boomboxes with regards to the circuitry.
Posted 07 December 2019 - 08:38 PM
Posted 07 December 2019 - 08:56 PM
Ok, I understand now. NO, I do not recommend that you do it that way. If you can not remove the slider properly, please do not attempt it. Those tabs fold over underneath and it's very difficult to bend them without direct access underneath. Furthermore, in my experience, the shell of sliders almost always have legs that are soldered directly to the pcb. In this case, look at the image and if you look at the corners of the outline where the shell would be, you can see 4 holes on each corner, almost surely representing where the location of the corner legs would be. Lastly, even if the 4 corners were not soldered on, trying to bend the tabs would almost surely exert a twisting prying motion which could damage the fragile resistor board and the small pins from the bottom. If you break that, you'll have no chance to repair the slider.
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Posted 07 December 2019 - 09:11 PM
Also I guess the sliders not making contact is basically telling the unit to not throw any sound (or in this case just touching enough to play a little sound at full volume.
Can this be bypassed if there is no parts available to repair it. Ie can it be tricked into no slider and just stay at equal balance for right/left. Might be a silly question just curious
Posted 07 December 2019 - 09:43 PM
The resistor is basically operated as a variable voltage divider circuit. Not complicated but in order to develop a proper discrete replacement, one needs to know what the resistance values would be with the slider in the mid position. What I mean is this: If you look at the diagram, you can see the resistor with a symbol of an arrow near the middle. Basically, where the feeler contact on the resistor board dictates how much resistance from the feeler (needle on image) to each end. The values will be different and usually is not in the middle. For example if that was a 100k Ω board, the resistance in the middle position probably will not be 50k Ω from the needle to each end. Instead it might be 85k Ω to one end and 15k Ω to the other end. It is probably safe to conclude that the side with higher resistance is probably going to ground, and the other end can be shorted to the remaining end of the resistor board which should bridge the audio signal and allow it to pass to the amp. However, keep in mind that unless you take the slider completely out of circuit, which would require actually cutting the PCB traces, the loose feeler inside the board could actually short out internally where you don't want it to, or provide a path for parallel resistance, etc. In other words, the bypass you speak of is not that simple and if you were capable of doing that, you probably should likewise feel comfortable removing the slider and doing a proper repair on it.
Posted 08 December 2019 - 03:32 AM
I agree with Superduper. If you don't feel comfortable removing the slider from the board, then don't do it and ask your repair guy to do it for you.
I have worked on a bunch of VZ2000s and this is a common problem. In order to remove the slider you have to remove the tuning string so you can fold the board with the sliders up to reach the solder joints. Once you're that far, it is a matter of patience to remove the solder. If you force the slider to come out, you might end up damaging the PCB or the slider.
However, once you have the slider out of the PCB, it is a pretty simple task to fold open the tabs and glue the brushes back into place. Putting it back on the board is definitely easier than taking it off.
I've had about 10 VZ2000s open so far and I think like 6 of them had this exact issue (among other stuff of course). So yeah, that being said, I have a complete slider board if you require any spare parts. However, I think the balance slider might be faulty on that as well but it would be good for spare components like the little brushes nevertheless. If you need it, just send me a PM.
Posted 08 December 2019 - 10:48 AM
Posted 10 December 2019 - 05:43 PM
Once I get it repaired I have to look into my mitibishi interplay (front loading vinyl player) as well because it’s acting up now too. I think it’s just the belt tho.