VZ-2000 Disaster

[Friendy]

I'm hoping we've got some techies on here who may be able to shed some light on my disasterous night.

I discovered this site and have been reading feverishly but haven't posted until now. MadBadger is a good read for all VZ tinkerers. Beware the switch !

I got a VZ-2000XA a few weeks ago. When I picked it up, it was in 9/10 physical condition, barely a graze, only the TT didn't spin. Very happy boy.

After downloading the service manual and following the instructions, I discovered that I was certainly the first person to ever open her up - only the TT belt was perished -everything else was 100% intact and in excellent order. I ordered a new belt, installed it and BANG! I was in VZ heaven.
I've been playing it non-stop for the past 3 weeks, day and night. I work from home, so that's a lot of records. I don't know how I have lived this long without one. During the day, I started using it as a record player only - I plugged it into my valve amp setup via the AUX OUT rca's, turned the VZ volume down, and everything was sweet in VZ-2000 town.

Over the past 3 days, I've been testing the best way to run it off a 12v battery, the longer the better (I had my reasons, but they're seeming very irrelevant right now). I still had it connected to my valve amp with the volume down on the VZ.

I tested 2 different set-ups.
One involved a 300W DC>AC inverter with the VZ AC cable plugged in.
The second was a 12v to 15v, 6A converter - the type of thing that runs a laptop in a car.

The inverter ran well for about 20-25 albums until the alarm sounded. No problems, I think.

On the same battery, I then tried the converter. I used the VZ's DC input, chose the correct plug and I had the correct polarity . This system played a number of LPs, without a hitch, but after a while I switched to the radio (still through the valve amp). I had to go out for about 1.5 hours, so I turned my valve amp off but left the VZ running on the battery but with no volume out. When I came home I turned the power switch on the VZ off. It looked like the battery had run downa fair bit but the lights were still on - I didn't listen to it at this time.

Here's where the disaster struck - About 4 hours later I unplugged the DC and plugged the AC cable back in to the 240v wall socket, then turned it on . A droning, increasing in volume whistle, then a buzz/screach came through the VZ speakers as it warmed up (with the volume down to 0). I thought I had a broken rca cable, creating an earth loop of some sort, so I unplugged them, but it still came through, so I turned the VZ off. I then unplugged everything, reconnected it and tried it again - same problem, even louder this time, through the bass speakers only, it seems. I tried a record, a cassette and radio - all systems worked perfectly through the tweeters but the buzz/screach still came through the bass speakers. Volume up or down does not effect the buzz and no music comes through the bass speakers. I tried it with a new 100% charged battery and the same problem occured.

I am the unhappiest man in all of the Boombox kingdom right now. I think I have killed a 9/10 boombox but I don't know how.

Does anyone have any idea as to what I may have done and whether it is recoverable ?

Thanks in advance....

Friendy

 

[mmcodomino]

I'm hoping we've got some techies on here who may be able to shed some light on my disasterous night.

I discovered this site and have been reading feverishly but haven't posted until now. MadBadger is a good read for all VZ tinkerers. Beware the switch !

I got a VZ-2000XA a few weeks ago. When I picked it up, it was in 9/10 physical condition, barely a graze, only the TT didn't spin. Very happy boy.
[ Image ]

After downloading the service manual and following the instructions, I discovered that I was certainly the first person to ever open her up - only the TT belt was perished -everything else was 100% intact and in excellent order. I ordered a new belt, installed it and BANG! I was in VZ heaven.
I've been playing it non-stop for the past 3 weeks, day and night. I work from home, so that's a lot of records. I don't know how I have lived this long without one. During the day, I started using it as a record player only - I plugged it into my valve amp setup via the AUX OUT rca's, turned the VZ volume down, and everything was sweet in VZ-2000 town.

Over the past 3 days, I've been testing the best way to run it off a 12v battery, the longer the better (I had my reasons, but they're seeming very irrelevant right now). I still had it connected to my valve amp with the volume down on the VZ.

I tested 2 different set-ups.
One involved a 300W DC>AC inverter with the VZ AC cable plugged in.
The second was a 12v to 15v, 6A converter - the type of thing that runs a laptop in a car.

The inverter ran well for about 20-25 albums until the alarm sounded. No problems, I think.

On the same battery, I then tried the converter. I used the VZ's DC input, chose the correct plug and I had the correct polarity . This system played a number of LPs, without a hitch, but after a while I switched to the radio (still through the valve amp). I had to go out for about 1.5 hours, so I turned my valve amp off but left the VZ running on the battery but with no volume out. When I came home I turned the power switch on the VZ off. It looked like the battery had run downa fair bit but the lights were still on - I didn't listen to it at this time.

Here's where the disaster struck - About 4 hours later I unplugged the DC and plugged the AC cable back in to the 240v wall socket, then turned it on . A droning, increasing in volume whistle, then a buzz/screach came through the VZ speakers as it warmed up (with the volume down to 0). I thought I had a broken rca cable, creating an earth loop of some sort, so I unplugged them, but it still came through, so I turned the VZ off. I then unplugged everything, reconnected it and tried it again - same problem, even louder this time, through the bass speakers only, it seems. I tried a record, a cassette and radio - all systems worked perfectly through the tweeters but the buzz/screach still came through the bass speakers. Volume up or down does not effect the buzz and no music comes through the bass speakers. I tried it with a new 100% charged battery and the same problem occured.

I am the unhappiest man in all of the Boombox kingdom right now. I think I have killed a 9/10 boombox but I don't know how.

Does anyone have any idea as to what I may have done and whether it is recoverable ?

Thanks in advance....

Friendy

Sad story man
My only idea is that the plugs for external speakers and stuff and not clean...maybe plug and unplug them a fewtimes...
My only guess...sorry, I think it does not help too much

 

[Gluecifer]

I've never come across this problem, Friendy. I hope someone here can help you!

PS: I moved your topic from Collections to Tech Talk so you have a better chance of getting a helpful answer.



Rock On.

 

[Superduper]

Try the boombox using fresh "D" cells. If the problem persists, suspect the PS filter capacitors have failed.

 

[BMoney]

Why did you run it off a 12v battery? Then a 12-15v DC power supply? Why not just plug it into the wall if you're at home? Or if you bought it from a country that uses different voltage, why not get a converter that would've stepped it down/up to the proper operating specs?

 

[Friendy]

I've never come across this problem, Friendy. I hope someone here can help you!

So do I !

PS: I moved your topic from Collections to Tech Talk so you have a better chance of getting a helpful answer.

Ah, yes. Sorry about that - I forgot to check which forum I was in. Thanks.

Rock On...right back at ya.

Friendy

 

[Friendy]

Why did you run it off a 12v battery? Then a 12-15v DC power supply? Why not just plug it into the wall if you're at home? Or if you bought it from a country that uses different voltage, why not get a converter that would've stepped it down/up to the proper operating specs?

I go places where there is no AC power, so I was trying to find the best way to power this without buying 1000's of D cell batteries. I have a lot of heavy duty 12v batteries that I run lights and have run other 12V or less boomboxes from with no problem. This was the first time I tried a step up converter.

The 12v battery had the inverter connected to the terminals, then I connected a cigarette lighter socket to the terminals and plugged in the converter which stepped up the 12v to 15v @ 6A. The unit uses 60W/15V = 4A, so that's good enough.

All of these are the correct operating specs.

Trust me, I wish I had just left it plugged in to the wall now.

Friendy

 

[BMoney]

Oh ok. I wasn't trying to be critical. I was just wondering why you wanted to power it that way.

 

[Friendy]

Try the boombox using fresh "D" cells. If the problem persists, suspect the PS filter capacitors have failed.

I'll try this, but I think I know what will happen.

The irony is that I was testing these methods trying to avoid the D Cells !

Let's say the capacitors are blown, which is what I think may have happened. What can be done ? Are they easily replaceable by a service person ? I'm no good at fiddly soldering.

Thanks

Friendy

 

[Friendy]

Oh ok. I wasn't trying to be critical. I was just wondering why you wanted to power it that way.

No offence taken, my friend.

If you're thinking this, someone else probably will too, so I thought I might as well explain....

Friendy

 

[Fatdog]

My experience with droning, screeching sounds has always been an indicator of a dirty, internal record switch. It seems Sharp boxes are bad about that. Just for a quick test, pop a blank cassette into the player and press REC then STOP, REC then STOP, REC then STOP several times. If that diminishes the screech, then it is the record switch. Hopefully, it will be that easy.

Welcome aboard, and good luck!!

 

[sony_apm_fan]

Welcome to the site!

Sorry to hear about these issues with your VZ.

Trust me, we have all experienced similar things!

PS Capacitors should be a fairly easy replacement for a service tech, but try the battery test first along with Fatdog's advice.

As Fatdog metioned, these boxes are notorious for issues with internal record switch so his words of wisdom are great.

I too had issues once with a box droning and screeching, once I uninstalled my ex wife the noise vanished

 

[Superduper]

My experience with droning, screeching sounds has always been an indicator of a dirty, internal record switch. It seems Sharp boxes are bad about that. Just for a quick test, pop a blank cassette into the player and press REC then STOP, REC then STOP, REC then STOP several times. If that diminishes the screech, then it is the record switch. Hopefully, it will be that easy.

Welcome aboard, and good luck!!

Re-read the post. Fatdog might have a point although the OP did say he tried tape, radio, phono -- all the same. The battery, step up, step down, etc -- all might be red herrings. I still say try D cells first simply to eliminate the power source as an issue, then surely clean the record/playback switch. Although the other issue that sounds disturbing is that no music comes from the woofers? That does sound very unusual since although the tweeters are fed off the high pass capacitors, the woofers are connected to the same source as the tweeters.

 

[sony_apm_fan]

My experience with droning, screeching sounds has always been an indicator of a dirty, internal record switch. It seems Sharp boxes are bad about that. Just for a quick test, pop a blank cassette into the player and press REC then STOP, REC then STOP, REC then STOP several times. If that diminishes the screech, then it is the record switch. Hopefully, it will be that easy.

Welcome aboard, and good luck!!

Re-read the post. Fatdog might have a point although the OP did say he tried tape, radio, phono -- all the same. The battery, step up, step down, etc -- all might be red herrings. I still say try D cells first simply to eliminate the power source as an issue, then surely clean the record/playback switch. Although the other issue that sounds disturbing is that no music comes from the woofers? That does sound very unusual since although the tweeters are fed off the high pass capacitors, the woofers are connected to the same source as the tweeters.

Agree 100%, battery test first. Yes, it's odd that the woofers are silent - no bi amp on these ??

 

[monchito]

blown woofers maybe just a thought thou.....

 

[Superduper]

One blown woofer -- maybe. Both blown? A little harder to fathom.

Also, one thing is that this amp might have output coupling capacitors, usually 1000uf. The capacitors block DC but if they are shorted, then they no longer block DC and DC damages speakers. The thing is..... tweeters have an extra high-pass capacitor, usually 3.3uf or something small like that. That would allow AC signals to pass but not DC. Or maybe none of this has nothing to do with anything....

 

[monchito]

well looking again at that post he was playing with it and it was working if both speakerswere working before then he was hearing a buzz than the speakers might be ok.. or probably ok ,, the record bar sometimes when dirty with oxidation sometimes cuts sound off or buzzes i have had a few boxes do that and with only cleaning the record bar i was able to get it working again,, me i would try that first i belive its the cheapest and easiest if that does not correct the problem then it might be more serious problem...

 

[madbadger]

the second VZ i bought had a similar problem, when i tapped the phono switch the sound got louder (as if the switch had a dirty contact) i stripped it out and lubricated it with contact cleaner, since the rebuild its been 95% ok, i didn't play VZ 2 for around 3 weeks and when i did, sound was only coming out of one speaker, a few taps on the phono switch, a few crackles and pops and she was playing ok again.

I dont know if this will help, i hope its something as simple as this.......

At the moment in writing this, i have VZ 1 playing, about 3 hours now, when i first started to run her, side A was slow......but after one LP it was ok, now iv'e been running it regular, its ok.......

Lets face it, these units are 20+ years old......

If you had the correct voltage/amps i wouldn't think it would damage anything, but i don't really know that much about electronics......

just looking back on my photos of the insides of the VZ and it looks like the wires lead from the large speakers to the tweeters.......to me it looks like the input travels through/via the large speakers to the tweeters........

when i do the cassette deck i will take lots of photos close up.....

there is a switch on the back to switch to external speakers.......give that a twiddle !!!


hope it works out for you mate....

Kev

 

[floyd]

I'm hoping we've got some techies on here who may be able to shed some light on my disasterous night.

I discovered this site and have been reading feverishly but haven't posted until now. MadBadger is a good read for all VZ tinkerers. Beware the switch !

I got a VZ-2000XA a few weeks ago. When I picked it up, it was in 9/10 physical condition, barely a graze, only the TT didn't spin. Very happy boy.
[ Image ]

After downloading the service manual and following the instructions, I discovered that I was certainly the first person to ever open her up - only the TT belt was perished -everything else was 100% intact and in excellent order. I ordered a new belt, installed it and BANG! I was in VZ heaven.
I've been playing it non-stop for the past 3 weeks, day and night. I work from home, so that's a lot of records. I don't know how I have lived this long without one. During the day, I started using it as a record player only - I plugged it into my valve amp setup via the AUX OUT rca's, turned the VZ volume down, and everything was sweet in VZ-2000 town.

Over the past 3 days, I've been testing the best way to run it off a 12v battery, the longer the better (I had my reasons, but they're seeming very irrelevant right now). I still had it connected to my valve amp with the volume down on the VZ.

I tested 2 different set-ups.
One involved a 300W DC>AC inverter with the VZ AC cable plugged in.
The second was a 12v to 15v, 6A converter - the type of thing that runs a laptop in a car.

The inverter ran well for about 20-25 albums until the alarm sounded. No problems, I think.

On the same battery, I then tried the converter. I used the VZ's DC input, chose the correct plug and I had the correct polarity . This system played a number of LPs, without a hitch, but after a while I switched to the radio (still through the valve amp). I had to go out for about 1.5 hours, so I turned my valve amp off but left the VZ running on the battery but with no volume out. When I came home I turned the power switch on the VZ off. It looked like the battery had run downa fair bit but the lights were still on - I didn't listen to it at this time.

Here's where the disaster struck - About 4 hours later I unplugged the DC and plugged the AC cable back in to the 240v wall socket, then turned it on . A droning, increasing in volume whistle, then a buzz/screach came through the VZ speakers as it warmed up (with the volume down to 0). I thought I had a broken rca cable, creating an earth loop of some sort, so I unplugged them, but it still came through, so I turned the VZ off. I then unplugged everything, reconnected it and tried it again - same problem, even louder this time, through the bass speakers only, it seems. I tried a record, a cassette and radio - all systems worked perfectly through the tweeters but the buzz/screach still came through the bass speakers. Volume up or down does not effect the buzz and no music comes through the bass speakers. I tried it with a new 100% charged battery and the same problem occured.

I am the unhappiest man in all of the Boombox kingdom right now. I think I have killed a 9/10 boombox but I don't know how.

Does anyone have any idea as to what I may have done and whether it is recoverable ?

Thanks in advance....

Friendy

does sound still come from the tweeters ? , i think you should test the speakers using an external source once you have eliminated them as a problem you can move to the next step and thats to clean and lube the function and band selector switches and sliders and the record switch ,if that fails to resolve the problem it might be a power supply or other electronic problem , i hope you get her sorted out i love these boxes .

 

[Friendy]

First of all, thanks to everyone for their time and help with this problem.

I've actually got 3 VZ-2000s (I'm catching you Kev !).
- The super shmick VZ-2000(X) that I am having this problem with
- A VZ-2000(XA) that's in OK cosmetic condition but not working yet - sound out of one channel only.
- A VZ-2000(Z) that I just got yesterday, that I got working but has clearly been in a garage or by the sea for a few years, so it's cosmetically poor.

Just an update to answer some of the questions.....

- The buzz/screach came when the power was on, volume down, any source selected, nothing playing.
- With the volume up, any source selected and something playing, the tweeters worked but the buzz only came through the woofers - none of the music.

I had to pull the X apart to fix a broken slider anyway, so I decided to do some checks using the other boxes.
I had pulled it apart before I read all these posts, so I haven't been to get D cells yet, nor done that check.

- I tried the X speakers on the Z frame and they worked perfectly, so there's no problem with them.
- I tried to do a visual check to see if I could notice any bulbous capacitors around the power area but there's nothing that looks bad, but I'm no expert, nor do I have the correct equipment to test them. The wires from the speakers go up under the radio dial

I'm going to try the XA speakers on the X frame to see if I get the same sound.

I'll clean as much as I can and put it all back together over the weekend, test the D cells and see what happens.

Thanks again Boomboxers....looking forward to rockin' again.

F