Gnrl Discussion (it's about Dead VCR actually tech question)

[dinkob]

Hi.

My Multysystem Samsung SV5000 W died.

First issue I had with it was that it would eject the tape first unless you hit the power button which would turn it off but the tape would remain inside. However the playback would only work on SLP ! not SP.

VCR is usually on all the time (maybe I SHOULD turn it off - it's more of a forget to turn it off element than being lazy). My guess it probably burned out.

Now the VCR has died completely. You plug it in and power button is just red and nothing else works (display, tape controls, notta).

SO I decided to look at it and found something that could indicate what needs to be repaired.

These are the pics. Look at the condensor that's on lower right (condensator - whatever is spelled on the left side (there are 4 of them that are big)). It looks like a baloon on top and on the bottom it's pretty much torn.



(on this picture look at the torn bottom, you can't see that it's bent on top):



So my questions are:

Would you say that this needs to be replaced?
Has anyone here ever dissasembled the VCR (I am trying to figure out how to get there?)?
Is there a repair manual to maybe buy / download?

Well I know that this is not the right place to ask but I was thinking that someone may know since this place is crowded with good tech people.

Thanks ahead.

dink

[/img]

[Bob W]

Those capacitors are part of the power supply and do the filtering for the DC output that powers the various circuits and/or motors/relays of the VCR. I would at least replace the damaged one or maybe all of them since the caps are cheap.

[dinkob]

Thanks you SOOO much for confirmation!

I'll check out the Radio Shack when my Finals are done for the quarter.

B.T.W What could be a reason that this happens?

Also I forgot to mention that there is a high pitched noise coming from that area when VCR is plugged in.

Thanks soo much again.

Dinks

[Bob W]

A voltage spike on the ac line could have damaged the caps or they just degraded over time and temperature and finally failed. The noise you hear is most likely due to the now unfiltered (120Hz for a full wave rectifier) DC voltage output running all through the VCR. I bet the bad cap is vibrating and making that noise. If you want to check that out take a wood pencil and place the point on the bad cap while holding the eraser part or other end of the pencil to your lower earlobe and it will transmit any sound to your ear.

[Duchess]

B.T.W What could be a reason that this happens?

Aluminium electrolytics contain a liquid that ensures that the surface of the aluminium foil maintains it's oxide. However, no seal is perfect and over time it evaporates, particularly in a hot environment and eventually only a little remains and that can then boil if the oxide degrades and a high current passes through the capacitor with the result you are seeing.

If I were you I would replace all those capacitors as the others are probably also having problems, just not enough to actually blow up yet. Also don't be too surprised if other components (such as the rectifiers etc.) have been destroyed as a result of the capacitor failure.

[Roundabout]

If it wasn't for the fact that this VCR is expensive, I would suggest just chucking it and getting a new one. However, I know this unit costs quite a bit and is a worldwide voltage/conversions VCR and you want to keep it working (so would I!).

You could use a ohm meter to check if the Caps are shorted or not. It's best to remove them from the MCB first, because other components in the circuit could affect the reading.

You have to pay careful attention to the polarity of the caps, these type of electrolytics have a definite polarity and should be marked on the side with a (+) and must be replaced the same way. Smaller Mica Caps don't have a polarity, but they don't give as much trouble as the electrolytic type.

You will also need a volt/ohm meter to check voltages, and I would suggest ordering a schematic from Samsung - even if it turns out you don't need it now, the nominal cost will be worth it if you can't get one later and they go out of print. Sony had many manuals through the years that they just stopped printing because the lack of demand, often we were the only ones that had one in the United States!

With a schematic you could check voltages and verify if they are correct or not. As Duchess noted, quite correctly, there could be other components affected by the failure of one or more of the capacitors. Also, if a diode shorts and puts AC through an electrolytic, that could be the reason for failure. Sometimes the caps dry out, and then short, but the age of your unit most likely precludes that scenario.

If the caps are defective, they could have just failed on their own, or other reasons like I stated above. Power supply problems in general are the easiest to diagnose, unless there is a problem with a switching type (transformerless) supply (apparently not your case).

Since the capacitors are generic, you can just get them at Radio Shack or wherever, but make sure they are at least the same voltage rating or higher, and the capacitance is not as critical as long as it's close to the original value, for example, you could replace a 1000 mfd (microfarad) cap with a 1200 or 1500 mfd. with no problem in this case, as it's only a filter cap, not critical as in RF circuits. You want to be at least as much or more than original though, don't go lower. If they're rated at 35 volts, might even be a good idea to go with higher, such as 50 v. or more (assuming they fit physically).

After you do all that, check back in and let us know what you find.

[dinkob]

I'll definitely check back with you guys to see how it went.

See the reason I bought this VCR is becuz of the PAL conversion (Part of my family and friends family are still in Europe and there is a lot of mateiral people come by and ask me to convert it (which I do for free; weddings, soccer games; my latest conversion was Bosnia vs Denmark b.t.w. heh, good game!)

What I don't get is that the VCR that I bought in Europe (which I thought was going to work with my Hauppage card; supposedly supports PAL BGIDK does not) has NTSC playback built in while American made VCR-s don't (at least I haven't found one yet).

So yeah, the cash that I paid for this unit was 300 bucks.

On top of that what I had to do was use both European VCR and this one (since it had damaged playback) to get the PAL converted to NTSC (tape playback was bad on SP mode but the converter did work so I used RF input and set the Samsung to Italy setting).

Moreover I am not quite happy with this Samsung although the unit itself looks really good.

The problem is that for some reason bumps up contrast on NTSC for about 50%. In other words Cable TV input NTSC contrast is alrady boosted, after recording and playback it bumps it again! so you have a picture that is just white white white it hurts your eyes.

Grin! gotta go study.

Dinks

[dinkob]

Hi guys.

I am having a real tough time finding the capacitor. The closest I could find is 1000uF (U with tail micro farad I think) 35 Volt.

The one I need is 16 Volt, 1000uF.

I think one of you guys said that I can go higher but I would like to confirm with you first.

Dinko

[Bob W]

Hi guys.

I am having a real tough time finding the capacitor. The closest I could find is 1000uF (U with tail micro farad I think) 35 Volt.

The one I need is 16 Volt, 1000uF.

I think one of you guys said that I can go higher but I would like to confirm with you first.

Dinko

Yes going to a higher value and voltage (and even a larger cap) is actually better than the original since it will do more filtering. 20 uf is a common value. Also even a slightly smaller value would work as long as the voltage is rated at 16 or higher volts.

[dinkob]

Let the pictures speak for themselves.

*it's a little blurry (gee I can't even use a digital camera properly %gulp%)

New capacitor (I elevated it so it doesn't clash with other ones)



Drilled a hole on the bottom of VCR so I don't have to pull out the whole thing.



VCR working again (however it works good mechanically - it doesn't eject the tape anymore - SP mode on PAL to NTSC still doesn't work and so NTSC to NTSC SP mode also doesn't work - but I have another PAL (Panasonic) vcr and hopefully I can use a SAMSUNG converter to link PANASONIC > SAMSUNG > JVC (or without JVC) to my Capture card - eh! - (( remember when I said that I have to set Samsung to Italy and I think it's program 38 where my Panasonic wants to spit picture to)



This is the old DEAD capacitor.



Thanks for all your help. NOW I'll make sure I turn it off when not in use.

Dinks

[/img][/i]

[Canoe164]

I am so impressed with this site...always help to be found through the skill of others.

[Roundabout]

Hey, glad you got it going again. Just to make sure that you don't have AC going through the new capacitor, you might want to do a cursory check - the cheating way. Just put your finger on the top or side of the cap and make sure it isn't getting hot. It could be a tiny bit warm which is o.k., but it shouldn't run hot. If it does, it might fail again. If it's cool, you're home free most likely. I don't know how many times I changed parts and got something running again, just to have it come back a week later for the same failure. Not saying that will happen here, but just check to make sure the new part isn't too hot. The higher voltage rating, as I said before, is always a good idea, assuming the part fits in the unit.
Good job on cutting the hole on the bottom so you wouldn't have to remove the MCB - looks like something I'd do.
You mentioned that some of the modes don't work properly - maybe just a case of clogged heads. Have you tried a wet tape cleaner or a lapping tape?
Anyway, glad to know that it works again and hopefully will keep working!

[dinkob]

I have cleaned the head manually just now with Radio shack tape head cleaning alcohol (actually - I got pissed cuz I couldn't find that one at first so I used 91% isoprophyl from walgreens; if that matters - then I used the tape head one) with some cloth that wasn't quite soft but it should have cleaned the head.

The head when I look at it now (could attach a pic) looks a little greysh, not quite crispy crystal clean.

I am thinking about getting the flat q-tips design for this kind of work (used to do this at best buy when I worked there).

What confuses me is that the SP mode doesn't work on either system while SLP does work great! (at least I can say this for NTSC to NTSC - but also if I record something to PAL in EP mode the playback from PAL EP to NTSC is ok as well (of course like I said I use THIS VCR to record to PAL in the first place).

Maybe I could try capturing something in EP mode with my Panasonic PAL VCR but that would be a little difficult... (to properly test EP PAL mode on Samsung).

Geez I am going in circles here.

Dinks

[dinkob]

Ok last update:

After cleaning the head thoroughly (I noticed the brown line on the cloth when I cleaned it up) this is the PAL playback.

Here's a pic (I think the green line says it all > some component died for sure). On top of that picture goes from up down very fast with lot of snow present.



So, it looks like I could just use my other VCR to play PAL SP tapes.

Picture though seems somewhat Jumpy (slight motion up and down - nothing to annoy toooo much out of you). I think this is becuz of old recording (Croatia > Jugoslavia in 1970!) and there is some flicker as well.

Now this is NTSC to NTSC SP mode playback (one armed boxer SP tape).

I couldn't get picture at all (had to do fast forward):



Soooo I think I should just stop here. Maybe it will fix on it's OWN (gosh if I could just get PAL SP working it would be great!).

Thanks for all your help.

Dinks

[Roundabout]

If I remember correctly, there are usually 4 heads on the drum, and it's possible that one of them is clogged causing the bars you see on the SP playback for NTSC. Two of the heads are for EP playback and if they aren't clogged, the unit will play OK on EP but not on SP (which is using the opposite two heads). They are optimized for the gap necessary for the playback of each format (SP/EP).

You should use chamois swabs and denatured alcohol (not isopropyl, which tends to smear crud around and leave residue). If you use a cloth, you risk snapping off the head, especially if you use a up/down motion on it. You should always use gentle force and hold the swab steady while spinning the drum by hand slowly.

Because it is easy to damage heads, generally most people use a cleaning tape, wet or dry type. As long as you're careful you can clean it by hand as you've done - just be very careful. You shouldn't see any residue on a clean head or drum. Also clean the pinch roller and audio heads while you're at it.

[NightWing]

The problem can be if that cap went, it could take out other componets down the line or damage others. If you can get a circuit diagram with voltages and waveform charts could verify if everthing is working. Beyond just a voltage check would require a repair shop with equipment to check it fully out.

The key is if it takes a 1000uf then replace it with a 1000uf. No more or less. Its ok to use a higher rated voltage just dont go lower! A bigger value will take more current to initaly charge which could damage parts before it.

If you pop a Tantalum { the ballon shaped one } they usualy pop a hole and ooze a silver blister or the top explodes when they go bad.

Hate those alumium confetty generators! When they pop you usualy get a sticky oily substance with paper all over everthing! Hated to clean out Swan MB40/MB80 Transevers comming back for service. Would even find junk in the sealed vfo compartment!

Good luck!

[dinkob]

Oh ok thanks for the info.

One last thought. So after cleaning no Success.

However if A PAL source which is my PANASONIC works through RCA then conversion itself works (most important thing).

So most likely it's head that has been simply damaged (if 2 are used on EP mode and 2 for SP mode) because even NTSC to NTSC SP doesn't work. I don't know if head can be replaced but I can certanly give it a try depending on how much it cost$.

Maybe replacing it would work but I'll leave that for later.

[Roundabout]

Yeah, heads aren't cheap, and it's hard to replace by yourself. They have to be aligned when you put a new drum in, and you have to have an alignment tape and a good oscilliscope. Sony head drums were $75 -200 depending on model. So we're talking about bucks here. Most likely this unit will cost a bit to replace the drum too. If you find a good wet cleaning tape, you might try that. Beyond that, it probably won't be worth it to you to invest in a new drum assy. because of the cost vs. new unit. At least you can do some things you need to do with it anyway.

@ nightwing:
I worked for Sony for many years and never once had a problem replacing a filter cap of, say, 1000uf with one like a 2200uf. It's not critical in a power supply circuit where it's only filtering AC out. While it's true that it does take longer to initally charge, we're only talking microseconds, and it is not enough to damage a diode or voltage regulator in any unit I've ever worked on in my lifetime. The only thing that is critical is that the voltage rating has to be at least what the original component was or higher, and obviously the part has to physically fit in the unit.

[NightWing]

You can but with the design of todays electronics shaving cost here and there would be carefull.

I agree on the voltage rating. Either equal or better. Never lower.

Remember getting a replacement head on a Beta unit. Sheech that was expensive!

[VideoJockey2002]

How about buying parts from Samsung?

www.samsungparts.com

I'm considering buying this VCR because lots of old shows and movies I want are out of print. For some reason, I'm finding a lot of them in PAL format through dealers in Europe. I live in NTSC USA.

That Samsung has caught my eye because, even though expensive, it looks as though they sell parts via Samsung. I can fix a VCR as long as I can get a handle on a parts source.

There's two or three other factory authorized service centers/parts outlets listed on that page as well.

If you try and are successful, please post about experiences with SamsungParts. Just because the web site lists the VCR parts, doesn't really mean they are available. If you are able to buy what you need, I'll go ahead and buy the SV5000.

By the way, while it was working, were you pleased with the output on formats that did work?

--vj2k