A Learning Experience - Sharp VZ-3000 Restoration

 

I don't think I'll be able to outdo this one anytime soon. By complete dumb luck, I stumbled upon a rare and completely bonkers Sharp VZ-3000, just a short jaunt down the interstate from where I lived. Not knowing a single thing about what I was getting myself into, I parted ways with $100 and loaded this monster into my car. What ensued was months of trying not to rip my own hair out in the hopes that I could bring this unique machine back from the dead.

To me, Sharp has always been kind of an anonymous brand here in the States. They seemed like a down-market version of LG - which sounds a little mean but honestly, who gravitates toward Sharp over literally anything else? Hell, I can't even remember the last time I saw any of their products in a store.

That wasn't always the case though, as 1980s-era Sharp produced some of the most insane looking gadgets I've ever seen. There's the CT-6001 boombox, which has a freakin' analog color TV crammed into the front of it. The RP-117 turntable; a tray loading contraption that makes playing vinyl records nearly as easy as playing a CD, even down to sensing individual tracks. And of course, the VZ stereo series, which are a bit of everything: all of it ridiculous.

It's like Sharp's engineers went to work, brainstormed as many random ideas as they could in one sitting, before setting up a dart board and designing a product out of whatever they hit - while blindfolded and after doing several rails of coke. You've gotta love the Eighties'.

The VZ-3000 is a prime example of Sharp's insanity. Instead of just building a bog-standard home stereo system, they opted to cram a whole damn linear tracking turntable into the thing. Oh, and why not vertically orient it, make it play both sides without touching the record, and give it a power door - because why the hell not? The result is truly a sight to behold and it was evidently also very expensive. A new VZ-3000 retailed for around $750 in the early 1980s, which is now roughly equivalent to $2500 in today's money.

Even in the condition mine was in, the VZ-3000 is an incredible looking machine - like the kind of device you'd see in the backdrop of an 80s sci-fi film. It still looks futuristic over four decades later. I couldn't even imagine what kind of stares it would've gotten back then. Two other things quickly became apparent. First was the size, which if you know how big an LP is, you can get a pretty good idea of how big the VZ is just by looking at the picture.

Second was the level of grime that coated every inch of the machine. The prior owners of this machine were clearly prolific smokers and judging by the potency of the smell it gave off, it was smoked around fairly recently too. I normally wouldn't touch gear this putrid smelling or looking, but I was willing to make an exception for the VZ.

The first order of business was obviously cleaning the shit out of this thing. The smoke had penetrated so deep that I needed to tear down the entire machine if I had any hopes of eliminating the odor. I started off with the CP-V300H speakers, since they were the least complex in terms of assembly. I used a combination of IPA (isopropyl alcohol, not the gross stuff that passes off as beer) and Magic wood cleaner for the veneered MDF cabinets. Wiping the gunk off these speakers was equal parts gross and cathartic, returning the faceplates to their original sparkly silver finish.

These are bass reflex ported. Can you see where that is? It might take you a minute.

With the grills off I was able to do a more thorough assessment of the condition of these speakers. These are the largest bookshelf type speakers I own, with a 2-inch tweeter and a beefy 6-inch woofer though they're not going to win any contests on build quality, having paper cones and all. They weren't in bad shape but predictably, the woofer surrounds were totally gone so I needed to refoam them.

This was an easier job than I expected, though there are some precautions to take. I scraped away all the old material first and vacuumed away all the debris since I didn't want to get any stuck in the coil with the dust cap removed. After that, I pried off the dust cap and shimmed the space between the magnet and coil with two small pieces of paper. This is to keep cone perfectly centered so that when the glue sets, the magnet and the coil won't rub - not a step that you want to skip. 

From there I just used Aleen's Tacky Glue and applied the new surrounds to the cone. It's a little tricky getting the inside lip underneath the cone but give the cone a few gentle presses and everything lines up really well. After the cones dry, then the dust caps can be glued back on. During this process I also took the time to replace the feet on the bottom of each speaker and clean the mesh grills. I just took a five gallon bucket with a splash of laundry detergent and soaked the things for a few hours.

And presto! Like they were never smoked around. I did discover later on that the speakers have a 5.6uF 50V capacitor that could warrant replacing but Sharp curiously neglected to list them in the service manual. But if they sound fine, then it really doesn't matter. It's also worth mentioning that these speakers have really odd two-pin DIN plugs on them opposed to just regular speaker wire terminals. In fact the entire machine is comprised of really weird connections, with a five pin DIN socket for AUX and antenna connectors that I don't have the first clue as to what they are.

Evidently, DIN was the standard for audio hookups over in Europe and according to the guy I bought the VZ from, it was originally purchased in Germany. I don't know if all European or international VZ-3000's are set up like this, or if only the one's that included the CP-V300H speakers used DIN plugs regardless of region. Another point corroborating this, is that my VZ has buttons for MW and SW radio, opposed to just AM, whereas the North American model I bought for parts only has a button for AM. So that was an interesting find, and the changes go even deeper. More on all of that was we go.

With the back panel off, we get our first look at the chaos inside of the VZ-3000. Apart from the sheer amount of circuitry in this thing, the overall construction of the machine makes a whole lot of sense. The grey and silver outer casing of the machine is more or less just a cover for the internal chassis that holds all the components. Each piece is fairly easily serviced independently of the rest of the machine, the tricky part is actually getting it all out.

If it wasn't immediately obvious by the sheer size of the unit, the VZ-3000 weighs a goddamn ton, at roughly 32 pounds. Trying to maneuver the heavy chassis out of the relatively flimsy outer casing is an exercise in strength and patience. You don't want to set this thing down the wrong way and accidentally break a piece under it's own weight. What also sucks is how the chassis is actually attached to the body. There are seven screws on the inside of the chassis, but also eight smaller screws on the bottom, plus two large ones for the turntable bushings. 

I kept the screws inside the unit in place while I turned it onto the turntable side to remove the ones in the bottom. Afterwards, I turned it upright and removed the seven main screws, freeing the chassis. But before it can be removed, the door has to be opened, which without power has to be done with a hidden lever through a hole in the back of the unit. Hilariously, Sharp provides a wooden dowel rod with the machine specifically for this, and it even has its own dedicated mounting place on the back of the unit. I guess they assumed not everyone has a pencil, or a screwdriver.

I decided to focus my attention on the turntable since it's kind of the centerpiece of the VZ-3000 and it was the only component that was absolutely non-functional. After removing the bottom two screws aligning it with the bushings, the turntable comes out with just four screws and the unplugging of two cables. Immediately I noticed that the turntable needed belts, both for the platter and the door/tonearm mechanism. 

Thankfully, replacement belts are readily available online. The swap requires the removal of the turntable's PCB to access the large backet the platter rotates under, which itself is strung by ziptied wires that greatly limit it's movement. Plus, you're constantly fighting the nasty black sludge left over from the remains of the old belt, on top of the new belt constantly slipping around as you try to work it around the platter. It was all a bit of an chore.

Actually, that's an understatement. It sucked hard - and it was only going to get worse.

The problems were a lot deeper than just simple mechanical faults. The turntable was flat out unresponsive to button inputs most of the time, despite voltage readouts on the microcontroller appearing that it was working properly. I won't lie, being relatively green to this level of electronics troubleshooting, this PCB was freaking me out. I didn't know where to start, and I made all kinds of incorrect assumptions as to what the potential culprits were. Maybe it's the microcontroller, or maybe it's the resistors? Yeah, I forgot that resistors behave differently in parallel. Idiot.

I felt like I was going cross-eyed looking between the schematic and the board, aimlessly probing the hopes I'd find anything at all, but it was all fruitless. My methodology (rather, my lack of one) going into this troubleshoot was complete shit. I didn't fault trace. Plain and simple. I didn't start from where I was seeing discrepancies and work my way back through the respective circuit to see if I'm getting the expected outputs at each stage.

Well shit.

Things quickly got worse. During my troubleshooting process I accidentally rotated the rest position gear too far in the wrong direction, and it snapped the rest position microswitch. Okay, no big deal. I can just 3D print a new housing. Well not long after that, transistor Q535 decided it wanted to go up in smoke... and the power supply died shortly afterwards. Looking back, there's a very good chance I accidentally caused a short while I had the PCB loose against the metal bracket it sits on. Between the broken microswitch, the dead transistor and power supply, on top of my complete incompetence - I was in a bad way. 

Out desperation, I ordered a second unit for parts. Since I had basically convinced myself that I had no idea how to troubleshoot the unit, I thought rolling the dice on replacement parts out of a junker was my best route going forward. My plan was to swap over the power supply and turntable and give myself a clean slate to work off of going forward. The modular design of the VZ-3000 made this quite easy, though I did have to solder a few wires coming off the power supply going into the amplifier board and the speaker outputs.

As I mentioned earlier, this junked VZ-3000 was a North American model that sported a couple of differences compared to the European model I was restoring. The NA model power supply has only 120 and 220 volt AC as selectable inputs, while the Europeon model has 110 and 240 volt options as well. There is only a single fuse on the fuse board for the NA model versus four on the European model, and the amplifier chip is a more powerful STK463 at 25 watts per channel versus the European's STK461 at 20 watts per channel. I'm not sure why Sharp felt the need to make such extensive internal differences between regions, but all the parts seem to be interchangeable.

The new turntable actually left me in a better position than I was in with the old one; it wasn't completely dead. In fact, the door actually opened and closed with the push of a button, albeit only when everything except for power to the microcontroller and the door motor was unplugged. That was a little encouraging but after weeks of fighting the stupid thing, I really needed a break. For a few months I opted to cut my teeth on some smaller projects involving some less taxing electrical work, but it all really built my confidence back in trying to tackle the VZ again. 

There's a general rule of thumb regarding vintage electronics: you're going to need to replace the electrolytic capacitors sooner or later. If you buy an old piece of kit and it's not working properly, there's a decent chance that the caps are to blame. In the case of the VZ-3000, there's about 140 electrolytic capacitors in the entire unit. Considering that the thing is over forty years old, I figured it was worth a shot. I ordered all the capacitors off DigiKey and it ran me just over $54.

I was unsure about the purpose of these two bodge caps under the PCB since they didn't align with the schematics in the service manual, so I removed them.

My first target was the PCB on that goddamned turntable. Armed with a cheap soldering iron and a copper wick, doing caps is actually fairly easy so long as you take your time and double check your work. The VZ's PCBs are pretty well labeled so you have a lot of guidance on which caps go where, and what orientation they're supposed to be in. If there were any old bodges, I removed them unless the service manual specifically called for them to be left in.

Starting off, I just did one capacitor at a time until I was comfortable enough with the whole process of bouncing around between the PCB and the service manual. At that point, I would just desolder all the caps on the board, insert all of the new ones and bend back the leads, double check the board to make sure all the new caps are the right spec and installed correctly, then tack everything in place and snip the excess leads. Doing a good job of desoldering is very important because the last thing you want to do is accidentally rip up a trace when you pull an old cap out. Fixing one isn't the end of the world: just bridge over the trace with a bit of wire, but you'd rather avoid having to do this at all.

But all that tedium was worth it.

After rebuilding the turntable and hooking it back up to the rest of the unit, I grabbed one of my junk records and powered the thing up. The door opened on the button press as expected, but after I dropped the record in and let it close - lo and behold, it actually started playing it! I checked all the other functions such as cuing, repeat, and side B playback, plus I also took the time to get the speed dialed in. Everything about the turntable finally seemed to be working as intended.

Of course, that wasn't the end of it all. I still had eight more PCBs to finish; three of them at least as large the turntable board. I ended up not doing the radio portion, one because it seemed to be working fine, and two because I couldn't figure out how to remove the thing without breaking something. The chromed, plastic buttons on the toggle switches were nearly impossible to remove, as was the plastic pulley connected to the tuning dial. 

This was also a really good time to clean the contacts of all the potentiometers and switches on the unit. What I found during my initial audio tests was that the input toggles switches were a huge part as to why the sound quality was terrible and channels would drop. I'm speculating, but I'd imagine their proximity to the outside of the unit meant the cigarette smoke wasn't too kind to them over the years. Since they were mounted to the radio board, getting these switches cleaned proved to be tricky but I certainly got them sounding a lot better than they were originally.

That left the tape deck, which was surprisingly problem free. The belt kit I bought also included three belts for the tape deck so I figured I'd change them out even though the old belts actually looked okay. The only one I kept was the belt for the tape counter since the replacement belt for it was far too small, causing the entire thing to seize up when I pressed play. There was also one capacitor on the back of the tape deck that I replaced, and I gave the heads a good cleaning with IPA.

After one last test of the unit's functionality, I buttoned everything back onto the chassis and slid it back into the outer shell. Not nearly as obnoxious as getting it out although the buttons - especially the power switch won't immediately fall into place, and you don't want to try forcing the chassis in when they're not lined up. I had to help guide the power switch into position using the eraser end of a pencil. I also added new 3D printed TPU feet to replace the rotted factory ones.

It seemed unreal, but I finally felt like the VZ-3000 was finally ready for it's day in the sun.

I set the VZ-3000 up in the back room, popped in Lazerpunk's Death & Glory LP and Ministry's Twelve Inch Singles on tape, and let the thing sing. It worked. The road to this point was tiring and tedious, but in the end it all paid off. This gigantic, oddball stereo system was once again ready to entertain ears after god knows how long it spent languishing in dust and cigarette smoke. It tested my abilities, and almost won - but I didn't quit, and it was very much a learning experience. 

In hindsight, I could've done without buying a parts unit and maybe found that a full recap of the unit was unnecessary, had I been more patient and methodical in my initial troubleshooting. I ended up finding that the power supply failure was likely caused by a fused resistor that burnt up, and I found a blown fuse, giving more credence to the idea that I accidentally shorted the turntable board while messing around with it. Both of these would've been far less expensive to fix.

But what's done is done. The real question is: how does it perform?

Well, in terms of sound quality, actually pretty nice! I wasn't expecting the speakers to sound overly impressive since they're of pretty unremarkable build quality but they have decent clarity and a punchy low end, if slightly on the muddy side. I think the tape deck is by far the best sounding portion of the VZ-3000 and almost every single one of my old cassettes I ran through it sounded perfect. The turntable is no slouch either, despite it's overengineered nature. It tracks well and even though I was using the same four-decade old styli it came with, sounds respectable overall. I had also never used a linear tracking turntable prior to the VZ and I was pleased with how intuitive it was to operate. Cuing is a cinch, though it can be a bit annoying when you can't see the tracks on side B.

The VZ-3000 is not without its quirks though. It can't play transparent records without an adapter to cover the infrared LEDs used to sense record sizes - which I don't have. Mine in particular still has a few symptoms of age I need to eventually sort out. The input selector switches, while cleaner than they were, still sound a bit dirty and occasionally cause one of the channels to drop. Side B sounds noticeably quieter than side A (apparently this might be due to dirty contacts on the turntable's relay), and the turntable's door struggles to close under it's own power, likely the new belt is slipping or the motor is weak.

That really just demonstrates a bit of a hard truth about the VZ-3000. With how complicated this machine is, you really do get to point of diminishing returns quite fast with how many things can, and often do go wrong with it. It's not really doing anything that a "normal" hi-fi system already does at least as well, and more reliably. It's a novelty, but one that does a damn good job at trying to convince you otherwise. With how vintage audio has been blowing up in recent years, I wonder what's stopping Sharp from revisiting it's old dual-sided player concept. It's just cool as all hell.