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Posted by Michael Clark (Member # 369) on May 05, 2005, 09:38 AM:
Ok, I received my Sankyo 800 projector on Monday. It's worked PERFECTLY since then (I've already used it several times). Last night I was watching a film, and all of the sudden the projector light went out. The film continued running, with sound, but no light. So I turned the machine off and checked the bulb. I forgot to unplug the machine first, and as I began to loosen the bulb, I heard a pop and sparks flew. Now, there is NO sound, and the smaller, dimmer light under the sound head doesn't work. Although the machine still operates and feeds the film. I took the bulb out of my Sanko 460 machine and put in this machine and still no light. Has there been a short somewhere in the machine? It still operates, but just no souond and no light. And wouldn't you know it, I put the bulb from my Sankyo 460 machine BACK into it, and now IT doesn't work either! ARGHH!!! I get real nervouse about electrical issues, so I'm afraid to start tinkering with it. I do know (or assume) that in addition to whatever electrical problems may exist, I think the original bulb is ALSO burnt out, because I can hear a rattling sound when I shake it and also the bulb inside looks burnt. But the bulb from my Sankyo 460 does not look burnt out, but for some reason, it won't work either. So now neither machine has a working light.
I guess I'm really just venting here. I know I'll probably either have to take it somewhere for repair, or just put it up in the closet and eventually buy another one. I guess I should really get an Elmo.
Mike.
Posted by Alan Rik (Member # 73) on May 05, 2005, 12:51 PM:
That sucks. Is this the one off of Ebay with the 1200 ft reels and the 1.0 lens?
Posted by Michael Clark (Member # 369) on May 05, 2005, 01:34 PM:
Yes.
Posted by Mike Peckham (Member # 16) on May 05, 2005, 02:05 PM:
Sounds to me as though you've just blown a fuse [the projector that is, not you]. have you taken the back off and had a look at the fuses? It's a while since I've had a look in the back of mine but I seem to remember there being more than one fuse, that would suggest that different circuits are protedted by different fuses.
Some times a bulb blowing will blow a fuse, and if it was still powered up when you first tried to cahnge the bulb that would increase the likely hood of a fuse going.
Check them first and then report back ![[Wink]](wink.gif)
.
Mike
Posted by Michael Clark (Member # 369) on May 05, 2005, 02:54 PM:
I'll check the fuse and report back.
Posted by Alan Rik (Member # 73) on May 05, 2005, 03:13 PM:
Well I hope that its a fuse. ![[Smile]](smile.gif)
You got a pretty good deal actually. I was bidding for that machine before "Fishdr" had it. We were both bidding on the same item. My high bid was $400 and I bowed out. He won the auction for around $450 and then turned around and tried to sell it for $799. It didn't sell then he tried to sell it for $600. Finally it sold for around $300. He lost some money on it. Ah...the beauty of Ebay!
Posted by Kevin Clark (Member # 211) on May 05, 2005, 03:29 PM:
Hello Michael
Sorry to hear about your Sankyo troubles - I've owned a number of Sankyos in the past including this model and found them to be very robust and well designed so hopefully only a fuse has blown causing your sound problems now. It is unlikely the lamp from your Sankyo 460 would have lasted long as I recall it is a 12v 100watt lamp, with the Sankyo 800 using a 15v 150watt lamp it would most likely have blown it the moment you turned the dial to the lamp on position due to the higher voltage being applied. I'd recommend you check the lamp cable for breaks in the insulation especially where it bends tightly into the machine - suitable sized replacement lamp connectors and wiring are available from disco lighting unit suppliers if yours cannot be repaired or re-insulated. With the top of the range lens and 1200ft extended arms this machine has got to be worth repairing.
Posted by Jan Bister (Member # 332) on May 05, 2005, 08:18 PM:
Alan: the beauty of eBay alright, I was following fshdr's adventures in trying to make a fast buck off the Sankyo, too. ![[Big Grin]](biggrin.gif)
Kevin Clark: (why, welcome to the forum!) Good advice, it could indeed be the wire leading to the lamp, even the connector itself. But I too hope it was just a fuse - I recently blew something up inside my Bauer T450 and now the sound heads won't engage during forward projection anymore - I'm having to manually move the pressure pads up for the heads to pick up the magnetic track. Ugh ![[Frown]](frown.gif)
Posted by John Clancy (Member # 49) on May 06, 2005, 02:14 AM:
You can get almighty bangs from Super 8 machines when fuses blow. Anyone remember when the fuse in the Xenon went at the Top Hat club during a show about 10 years ago? Sounded like a bomg going off.
Posted by Kevin Faulkner (Member # 6) on May 06, 2005, 03:37 AM:
Yes even that dreaded mains filter in the Elmo xenons go with an horrific explosion as Tony knows too well when he was standing next to my machine when it decided to explode.
The Sankyo problem sounds a bit strange to me as I wouldnt expect the Lamp, Sound and pilot lamps to die due to a fuse unless they all come off the same transformer and the transformer itself is protected by 1 fuse. Even if this is the case I would expect the lamp, Sound etc to have their own fuses and also the main drive to be coming off the same transformer. Does the drive work?
Kev.
Posted by Michael Clark (Member # 369) on May 06, 2005, 06:08 AM:
Kevin, what is the drive? Sorry, I'm still learning here
I've opened the back of the machine and am looking for the fuse. Can someone point me in the right direction?
[ May 06, 2005, 03:48 PM: Message edited by: Michael Clark ]
Posted by Kevin Clark (Member # 211) on May 06, 2005, 12:47 PM:
Hello Michael. I'm sure by 'drive' Kev Faulkner was refering to the motors and film feed which you said are still working OK. Unfortunately I don't have a Sankyo 800 projector to hand at present or I would happily remove a fuse at a time to see if I could simulate your problem - perhaps another Sankyo 800 owner on the forum could try this to establish if a specific fuse is the cause of the combination amp / light faliure?
[ May 06, 2005, 03:07 PM: Message edited by: Kevin Clark ]
Posted by Mike Peckham (Member # 16) on May 06, 2005, 01:15 PM:
Hello Mike.
There is a third fuse in my Sankyo 800, it's mounted on the sound board below the fan and up close to the fly wheel. I've marked it with the red arrow on your picture below;
I tried what Kev suggested and removed one fuse at a time to see what happened. The fuse on the sound board [marked with the arrow] unsurprisingly isolated the soundboard and thus cut off the sound. The righthand of the two fuses together acted as a main fuse, when I removed that the machine wouldn't power up at all and nothing worked. Now, somewhat perplexingly the lefthand fuse didn't appear to do anything, I took it out and powered the projector up, even set it running with the lamp on and all seemed to work as normal. Hmmm...
I should add that on mine the two fuses are mounted on top of the alloy bracket that the mains plug is mounted in and not on the circuit board.
I don't think I've been much help but I should think that between us we should be able to solve this puzzle.
Good luck
Mike
Posted by Kevin Clark (Member # 211) on May 06, 2005, 01:31 PM:
Thank you for trying the fuse removal test so quickly Mike - lets hope the soundboard fuse is the one that has blown on Michael's machine. I think the fuse you removed that had no effect only comes into play when different voltages are selected on the multi-voltage dial.
Posted by Michael Clark (Member # 369) on May 06, 2005, 02:39 PM:
Kevin, is THIS the fuse block? When I remove it, there are 5 small metal pins. I don't see anything that I think of as a fuse.
Also, I noticed that the voltage dial is set to 117 volts. That's the setting it was on when I got it, but on my Sankyo 460 the machine is 120 volts. Is this machine set to the correct voltage setting? I don't know if the U.S. should use it at a different setting than in Europe?
[ May 06, 2005, 03:49 PM: Message edited by: Michael Clark ]
Posted by Kevin Clark (Member # 211) on May 06, 2005, 02:57 PM:
Hello Michael
My appologies - from looking at your clearer new picture I can confirm what I incorrectly identified as a possible fuse block is actually a connector so please plug it back in (if only I still had one of my now sold Sankyo 800 machines here it would be easier to assist you). Also the fuses that are SOMEWHERE around the mains transformer area have been confirmed by Mike to actually make the machine powerless when removed or blown so don't worry about those ones.
As Mike said in his post above the fuse to look out for is on the sound board, in the area marked by his arrow. This fuse will be a small glass cylinder about one inch or less long and about 1/4 inch in diameter - if you don't have a meter to test for continuity you can try to see if it has blown by looking at it up to the light to see if the wire in the fuse is broken. (this will only be possible if the fuse is made of clear glass and not an opaque ceramic material). I'm off now to remove the incorrect fuse block reference in my earlier post!
Regarding the projector mains voltage settings the 117v one should be OK for your location in the USA if your mains supply is 110v or 115v.
Posted by Michael Clark (Member # 369) on May 06, 2005, 03:47 PM:
Thanks Kevin. Ok. Mike, after looking in the area your red arrow points to up above, here is a picture of that area, looking down at the board (sound board?). Is that blue thing the fuse? Am I in the right area?
Thanks alot for everyone's help, this is helping me to really familiarize myself with the inside of my projector.
Posted by Jan Bister (Member # 332) on May 06, 2005, 06:18 PM:
No, that big blue thing is called a capacitor. Here's a good picture of what a fuse looks like: (note, this is a very close-up shot, they're normally quite a bit smaller than the capacitor in your picture)
Posted by Michael Clark (Member # 369) on May 06, 2005, 07:18 PM:
Jan, thanks for the picture! That's what I think a typical fuse should look like, but I can't find anything like that in the projector. Maybe I'm just missing it. I'll keep looking!
Mike.
Posted by Mike Peckham (Member # 16) on May 07, 2005, 03:23 AM:
Hello Mike
I'm afraid your Stereo 800 is a little different to mine inside. On mine there is a fuse just like the one Jan illustrated next to that blue capacitor, there are also two further fuses on top of the alloy bracket that the mains lead is plugged into. Looking more closely at your picture, I did spot a detail that isn't present on mine and might be a fuse holder - just to the left of the lamp flux switch. This might have a slot for a screwdriver on top and when unscrewed reveal a fuse that is forced in against a spring. Can't be sure though as it's difficult to tell on the picture but your machine must have fuses in it somewhere.
I have the wiring diagrams for the Stereo 800 and will attach one of them here but I'm not sure that it will be a big enough image to decipher. I could always email a bigger image to you if you think it might help. You will notice the two main fuses bottom right.
Mike
Posted by Michael Clark (Member # 369) on May 07, 2005, 06:16 AM:
Hi Mike! Here is a picture of that little box next to the lamp flux switch. 
There are three wires coming out of it - two from the bottom and 1 from the left side. It looks like the little box on the extreme bottom right of your wiring diagram. I have noted with a white arrow a little button that pushes in, like maybe it's some sort of re-set button. I was able to get the top screw off easy enough, but the bottom screw won't budge, and it feels like if I try any harder, I'll strip it.
There is still no sound or pilot lamp even after pushing this little button. I see the fuses pictured on your wiring diagram. This is strange. I'll keep looking around!
Mike.
Posted by Mike Peckham (Member # 16) on May 07, 2005, 04:11 PM:
Hello Mike
I don't think there is anything else I can suggest. From the description you gave in your original post it did seem as though the first thing to check would be the fuses. I wasn't expecting there not to be any, especially as my Stereo 800 has three ![[Confused]](confused.gif)
. I can't believe that Sankyo would have made a model that had no internal protection so can only assume that there must be either fuses or trips in there somewhere, but where is another matter.
Having said all that, the problem might not even be a fuse or trip, it just seemed to be the obvious first check. I have to admit, I am a little perplexed. I'll give it some more thought and if I have any more ideas I'll let you know, otherwise it's over to the other guys - maybe one of the two Kevins?
Good luck
Mike
Posted by John Whittle (Member # 22) on May 07, 2005, 04:50 PM:
Sounds like it's time to get out the old meter and start making continuity checks. Since the motor runs, there is still ac from the wall to the switch to the motor, but apparently all the voltages from the transformer (for the lamp and amp) are gone. So first check the wiring for where the 110 side goes to the transformer and make sure there is voltage there, then check the transformer output. Strange as it may sound there are some transformers withe INTERNAL protection and if that's what shorted then it's a matter of replacement. However, it's far more likely that a wire is off somewhere and only by tracing the circuit with a meter will you find it easily.
John
Posted by Kevin Faulkner (Member # 6) on May 07, 2005, 06:45 PM:
Hi Guys,
I have just looked at mikes circuit diagram and can see from that there shoulb be 3 fuses. The diagram shows a mains fuse, a fuse for just the lamp and one other for the sound circuits.
If Mike can email me this scan direct I can look at it more closely for you. I have to say that a quick look at this circuit diagram suggests that something more than a fuse is causing the problem.
Mike, can you email me a good quality sacn please.
Kev.
Posted by Mike Peckham (Member # 16) on May 08, 2005, 02:32 AM:
Kevin, will do .
Mike
Posted by Alan Rik (Member # 73) on May 08, 2005, 10:18 AM:
Hmmm...sorry to hear that the purchase was not so good. I guess that's the chance we all take with Ebay. The GS that I sold Dan literally died after I shipped it to him!
Luckily we have this forum and the great members. Best of luck..hang in there. From what I hear the machine will be great once it is up and running!
Posted by Michael Clark (Member # 369) on May 08, 2005, 12:27 PM:
Thanks Alan. The machine worked perfectly fine when I first got it, so I don't hold the seller at fault. I think it's just one of those things. Maybe the knocking around during shipping loosened something inside of it, even though it was perfectly packed nothing is full proof. Eventually I'll figure it out!
Mike.
Posted by Rick Skowronek (Member # 385) on May 09, 2005, 11:29 AM:
Hi, I'm a newbie to the forum but have 20+ years in the electronics side of the fence including design work. In looking at the wiring diagram one of you provided, there are only four things that could impact the bulb only. First, the bulb winding of the transformer (highly unlikely), second, the diagram shows a bulb only fuse. It is the left fuse and goes between the transformer and microswitch. I presume the microswitch is to remove juice from the bulb when it's cover is removed. Last is the microswitch itself and the bulb socket.
Since microswitches have been known to blow open sometimes before the fuse acts that is a distinct possibility.
In the order of most to least probable, find the fuse by tracing wires either from the lamp socket to the microswitch then to the fuse (hopefully easy to see). Then from the fuse to the transformer. Without an ohmeter/voltmeter and some electronics knowledge Michael should probably leave it up to a qualified service person. Could do more damage to the point of wiping it completely .
Rick
Just spent a little more time on the eye test diagram and Michael's pictures. It appears there are two microswitches potentially in the path for lamp power. The one on the diagram to the left of the bulb is probably the lamp on-off switch he shows in his picture right in front of the transformer. The other microswitch looks like it has something to do with voltage selection although I can't tell from the diagram. Too small. It is tied to the lamp microswitch though so may have some unknown impact on lamp power. Michael's picture is indeed the picture of the lamp power microswitch. When you move that switch up it should close the pictured switch. If the wiring diagram is correct, the fuse should be found by tracing the red wire on the microswitch to it.
I hope you guys don't shoot Newbies for too many edits and windiness. Dug out the magnifying glass and as much as these tired old eyes can make out, the microswitch on the right just below the transformer in the diagram is the switch Michael has pictured thus it has to be the main lamp power switch. The other microswitch has to be a safety switch located somewhere near the lamp housing. The main switch says it has two yellows and 1 red. The safethy switch which goes to the fuse looks like it has White as the wire to the fuse but really hard to read.
Sorry for the long post.
Posted by Michael Clark (Member # 369) on May 09, 2005, 03:11 PM:
Rick, thanks for the info. If I trace the red wire from the microswitch, it looks like it leads back toward the front of the machine. I may need to remove the panel on the front of the machine that has all the knobs and dials on it. I'll see this evening what I can do.
Mike.
Posted by Rick Skowronek (Member # 385) on May 09, 2005, 03:45 PM:
Hi Michael,
Yeah, sorry for the long windedness of the last. Was kinda thinking out loud. The thing is that depending on what and how you shorted the power when you pulled the lamp, a fuse may or may not have helped. The bulb power seems ultimately to route to many different boards.
As to the means to find that elusive bulb fuse, you actually will need to find that second microswitch (the one to the left of the bulb on the diagram) and to do that you will need to follow the yellow wire on the side of the switch you took a picture of (not the bottom yellow lead). That Red lead goes right to the transformer, the big object with all the wires behind the switch in your picture.
Once you locate the other switch, follow the White wire from it to the actual fuse. Maybe Kevin can verify the color of the wire to the fuse. I can't quite make it out but it looks like it says white.
Good Luck.
I'll do whatever I can to try and help.
Rick
Posted by Mike Peckham (Member # 16) on May 09, 2005, 04:42 PM:
Hi Rick
Welcome to the forum .
I've emailed you higher resolution copies of the circuit diagrams, hopefully you won't need the magnifiying glass for them .
Mike.
Posted by Rick Skowronek (Member # 385) on May 09, 2005, 05:16 PM:
Thanks, Mike.
I really thot I'd be going blind trying to track those lines. Don't know how much help we can be to Michael with out the benefit of a schematic diagram and he not being super electrically literate, though trying hard. These are the kinda probs that can be a devil to chase, but with the right equipment and lotsa patience, it pretty much comes down to following the electron path.
At this time I'd just like to lead him to the fuse for the lamp if it's there. It looks like the power for a lot of stuff comes through that circuitry.
Rick
PS. Just got your email Mike, and Michael, it is a white wire from the as yet unlocated second microswitch that goes to the lamp fuse. Actually I noticed there will be 2 white wires coming off that switch. You'll want to follow the one from the middle connection. Happy tracking.
Posted by Michael Clark (Member # 369) on May 10, 2005, 11:34 AM:
Rick, thanks for all your help. Thank you to everyone who is kind enough to help think through this.
I followed the yellow wire from the side of the first microswitch and it led to the front of the machine (I had to remove the front panel), and it led right to the 2nd microswitch. Also, there was a white wire that ran from the transformer, and met up with the yellow wire, and then both ran to the 2nd microswitch. Then, on the opposite side of the 2nd microswitch, there was a white wire that ran directly to the bulb. And then a white wire ran from the bulb back into the center of the machine (couldn't see where it went). So it appears as though there are no fuses between the first microswitch and the bulb. Also, on the 2nd microswitch, I couldn't find a small reset button like I found on the first microswitch. Although maybe it's out of my line of vision. Does any of this make sense?
Posted by Rick Skowronek (Member # 385) on May 10, 2005, 12:32 PM:
Michael,
You've got yourself a weird one here, for sure. That white wire going to the inside of the machine from the bulb looks like it ends up on a printed circuit card that has the audio output circuitry as well as other impossible to define functions from the diagram. I suspect it's that same circuit board you took a picture of with the blue capacitor on it. You might, as Mike suggested, have a good look at that black device next to the blue capacitor. I can't make it out from your picture but I have seen small fuse holders of that configuration. I would be surprised if it were though since the lamp draws around 9 amps of current so the fuse would have to be healthy sized (around 10-15 amps I would suspect).
One quick question on the yellow leaded microswitc, Does that switch control the bulb on off or just dim it like high & low light output. I suspect from the wiring diagram that it may be hi & lo light output by the way it's hooked up to the transformer.
Rick
PS. Mike Peckham and I have been going back and forth via email on this. It sounds like your projector, at this moment, is completely dead, right? No power to anything and you can't get the motor to run. Please confirm. I would say, in the absence of any other fuses, it has to be your main fuse that you blew. That is usually somewhere close to the power entry plug and usually accessible from the outside of the machine.
Please let me know.
[ May 10, 2005, 02:48 PM: Message edited by: Rick Skowronek ]
Posted by Rick Skowronek (Member # 385) on May 11, 2005, 07:59 AM:
Hi Michael,
Mike Peckham and I have been emailing like crazy on this. Just to clarify, you do have motor function, correct? The rest is dead. Without a new projector lamp we don't really know if that part works at all.
If the motor does work then your problem is probably more major than a fuse. Here's why. The lamp receives it's power from the two microswitches you tracked. The one on the lower right with the yellow and red leads is a brightness switch. When you move that switch to the up position it puts lower voltage on the bulb which makes it less bright.
The other microswitch that went to the bulb has two functions. It is the primary switch to turn the lamp on when you turn on the main projector control. It's second function is when your projector is plugged in but not running is to supply a very low voltage to the lamp. Not enough to light it but enough to keep the strain off of it when you do start the projector. The thoughts were to help the bulb last longer.
In Mike's version and on his diagram, that was the function of that second fuse he has. By your tracking it is clear Sankyo decided to omit that fuse. It would not stop the lamp from working as that fuse is out of the picture when the unit is running. Unfortunately for you, when you pulled the bulb with it plugged in, you shorted out that small "keep alive" voltage. Normally all that would have done is blow that fuse. Since it's obvious you don't have that fuse it's anyone's guess as to what took the brunt of the short. That's why my question of whether the motor was indeed still functional. You would still have to have a main fuse (hard to find, but there somewhere) but that would take power totally away from the projector and nothing would work. There are basically three independant power sources in the projector with the exception of the common transformer. One for the motor, one for the sound system electronics and one for the lamp.
Now what? One good test would be to get a known good lamp. Plug it in (with the power cord disconnected of course). Then fire up the projector to see if the lamp does light. I suspect it won't but this would point us in the right direction. It may be a joint common power connection was blown on the main PC card which then also shut down the sound. May be fixable with some effort but probably not by a layman. If by some chance it wiped the transformer, then you have a 20+ pound boat anchor. It's kind of unlikely though if the motor still runs.
I would be happy to look at it at no charge if there's a way you could pickup shipping in both directions but that's up to you. I have the necessary equipment to test it. Let me know on the motor still running question as that's the hinge pin of all the above deductions.
Rick
Posted by Michael Clark (Member # 369) on May 11, 2005, 08:10 PM:
Rick, I ordered new bulbs last week and they came today. And voila, it works! The light that is. So the motor runs and the light lights, but still no sound, and no pilot lamp. Does this info narrow it down some?
Michael.
Posted by Jan Bister (Member # 332) on May 11, 2005, 10:53 PM:
I'm curious as to what exactly you mean by "no sound" - I know you mean there's nothing to hear when you play a movie, but are the VU meters still showing a signal? Does recording work at all (does the projector "hear" a microphone or line-in signal)? I don't know if your Sankyo has two separate modes for sound and silent film, but if it does, are the sound heads engaged when in the "sound" position? (Pressure pads keeping film running over the heads?)
Posted by Kevin Clark (Member # 211) on May 12, 2005, 01:32 AM:
Hello Michael
Great to hear the lamp works OK now you have fitted the new one. As I originally mentioned the lamp from your Sankyo 460 would never have survived in this machine - 12volt lamps do not like 15volt supplies one bit - and it is more than likely the original lamp blew simply from fatigue rather than any other spurious reason. As it appears you may have a fuse-less design machine (unlikely I know but it looks that way at present) following the 'pop' noise when you disconnected the live lamp supply, the remaining problem of no sound is either a blown component on the amp circuit board or a very, very well hidden amp protection fuse (like the one on Mike's machine but situated somewhere else). One last thought about the fuse location - as your machine does not seem to meet the same design spec as other Sankyo models, have you laid the machine on it's back and looked 'up & underneath' the base of the projector (like a car looking up from an inspection pit) it's the only other place I can think they may have put outwardly facing screw-in type fuse holders or circuit breaker resets. This is definitely a machine worth fixing so the kind offer from Rick to repair the amp circuit board is the route I would recommend you follow now - see if he will also change the lamp connector as a safegard while he's at it
Posted by Rick Skowronek (Member # 385) on May 12, 2005, 08:20 AM:
This really strange how that short caused a failure. I won't give it 100% certainty but pretty darn close that your short on the lamp socket went through the motor control PC board (the one with the blue capacitor in your pictures) and took out the main power ground for the sound pc board. It's obvious you don't have power getting to the sound card because you don't have a power on pilot light.
You may ask how does a lamp short wend it's way over to a completely different PC board. There is one common spot for lamp power, motor power and sound power coming together and that's on the Motor Control PC board (the one you pictured). The sound board appears to be mounted directly underneath that board. Anyway, just above that blue capacitor is a spot on the PC board where Motor power comes in (the Gray wire), the return path for the lamp comes in (the white wire from the lamp socket) and main system ground for everything (a black wire from the transformer 0 volt tap). The white wire from the lamp and the black wire from the transformer would tie together on the PC board as well as another ground wire (black) to the sound PC board underneath. So, basically, in that one little corner of that PC board all system power grounds come together, lamp, sound and motor. It's not inconceivable that the short may have messed up the copper traces on the back side of it a bit to the point of opening the sound card's return power path. The fact that the bulb still lights and the motor runs is a bit of a mystery but the copper traces for them are probably much heavier than the trace for the sound power return.
Anyway, that's my WAG (wild ass guess). One thing to try just to insure that sound board power is still available is to try the projector in the dim lamp mode to insure the lamp still lights. That's because the sound power is also the same power that feeds the lamp in dim (low light) mode. If that works then it pretty much says that it's the ground area discussed above.
Let me know.
Rick
Posted by Michael Clark (Member # 369) on May 12, 2005, 12:06 PM:
Rick, yes, the lamp lights in the dim setting as well as the regular setting.
Jan, the sound head engages - I can see it move up. But the sound meter is measured in LED lights and they don't work.
Posted by Rick Skowronek (Member # 385) on May 12, 2005, 03:09 PM:
Well, guess we have it pretty well tied to an area. From the looks of your picture Michael, that's gonna be a real SOB to get at the bottom of that card since it sits above the the other card. I think if you could see under it, you would find a fairly small burned area that unfortunately acted as a fuse. It also looks like, from the pictures that it's difficult to even look back under the top and spot the white and 2 black wires coming in to their respective spots.
The Bar LEDs for the level also receive their power from the sound card power so they won't light either. The dead give away is no pilot light since it probably would light if there were any power at all on the sound card whether the circuitry was goofed up or not.Usually, the only thing that shuts down everything like all of the sound card would be power.
So, there you have it. You know pretty much where it is and what it is. Afraid the old ball, as they say, is in your court. Just be careful in getting at those boards if you decide to try. Another short or breakage could wipe some pretty bad stuff. Parts would be a devil (if available at all) to get and then you would have your boat anchor.
Last, I tend to agree with Kevin Clark on the lamp socket. It is highly unusual to see a short between the lamp pins just from wiggling the bulb out. Usually means something is wrong with the socket. Offer still stands if you don't have a local guy you can take it to.
Hope everyone enjoyed a long winded troubleshooting exercise. I know I did.
Rick
Posted by Michael Clark (Member # 369) on May 12, 2005, 04:06 PM:
Thank you Rick for all your help. And thanks again to everyone who helped think this one through. Rick, I think I'll try and look up under the bottom of the circuit board and see what I see, but barring some monumental discovery, I'm thinking I may just keep my eyes out for an Elmo ST1200D or HD.
The cost and trouble to pack up and ship this to you just isn't worth it to me. At least not right now. I've got my old Sankyo 460 back up and running after replacing its bulb, so at least now I can watch films again. And, I do have the Hi Pro lens that came with the 800, and that lens works on my Sankyo 460 as well.
I don't know if I want to put the effort into fixing the Stereo 800 or maybe I'll just sell it on e-bay for a really cheap price. We'll see.
Mike.
Posted by Rick Skowronek (Member # 385) on May 12, 2005, 05:03 PM:
Michael,
I appreciate your dilemma. It would end up costing you probably close to $60 or more for a round tripper. And, while certainly appropriate to try and resell, I'm sure you'd feel somewhat remiss trying to explain and the obvious amount of effort to repair same. You may not get even one bid for all your effort. If you have some level of soldering capability as well as a multi-meter to test voltages, I'd say give it a go.
With that said, you know I'm looking for a projector to get started. Believe me, I haven't lead you astray at any point. Would have loved for it to be something that you could've done. You can kind of blame Sankyo for removing the obviously needed protection that would have saved much of this situation.
If you are going to dump it, please let me know. I would be happy to give you something for the projector and pay for shipping it to me. Obviously, that won't recoup your loss but at least you know it's going to someone who knows what the problems are and will take the risk. Let me know what you think and if that sounds fair. Otherwise, good luck on it and really sorry for the problems caused by a problem lamp socket. Shouldn't have been that disastrous.
Regards,
Rick
Posted by Kevin Faulkner (Member # 6) on May 12, 2005, 06:30 PM:
I have a different theory. After studying the circuits I can see that the lamp runs off low voltage AC there is also a seperate recitifier for the motor control circuitry and likewise for the amplifier and all that is associated with it.
I dont think its the neg supply gone down but possibly an open circuit rectifer block for the amplifier and its associated circuits including the led meters. At this stage in the game its a case of checking the supply voltages from the rectifiers. They are not switched so should both have a voltage present. Looks like they are both on that motor control board in question. Its important though to note that the Lamp, Motor and amp have 3 seperate supplies.
Kev..
Posted by Rick Skowronek (Member # 385) on May 12, 2005, 07:53 PM:
Kev,
I appreciate someone else in the pool but let's recap just to insure I'm not too far off base. I agree on the three supplies and confirmed that about 9 posts above.
First, we all agree I presume, that the AC voltage is present for the sound card (going to the sound card via the orange wire from the transformer). If it wasn't there then the low brightness function on the bulb wouldn't work. It also supplies that. The motor voltage is present from the transformer as it runs and is supplied to the Motor control board (which also serves as a main connection point for many circuits) but especially the bridge rectifier for the motor control as well as all grounding/common points for all three power circuits. Please take a close look at the wiring diagram provided by Mike Peckham. The orange power wire (13.5 volts AC) for the sound circuits goes directly to the Sound Card. See schematic for exact clarification. I presume the bridge rectifier for the sound circuit is located on that board.
Now, understanding that the short circuit was through the two pins of the lamp connection, there is only one place where all the commons meet up. The 0 volt tap from the transformer that provides the "ground/common" is located on the upper right corner of the motor control card (via it's black wire shown on the wiring diagram) and also connects to the lamp for it's common, including the 2.9 VAC "keep alive" voltage via the white wire from the lamp socket, to the same spot which is what actually shorted. The only place where something could impact any of the power for the sound card is there and only via the common. It could not get to the sound card in any way shape or form since the common is right there tied to the lamp common and the common transformer lead. The sound card has just another common wire from that spot to it's card (next to the orange wire on the sound card) also colored black.
What I'm trying to say is that there is absolutely no way for a shorted set of lamp leads to find it's way to the bridge rectifier of the sound card. The fact that the motor runs and the lamp lights and no pilot light on the sound card says that it isn't getting any power whatsoever. Yet, his low lamp is getting power which means the sound card is getting the "plus" 13.5 volts AC that it's supposed to. It's missing the common from the black lead from the Motor control board whatever in the short caused that.
If you have another explanation, I'd be happy to hear it.
Thanks,
Rick
Posted by James N. Savage 3 (Member # 83) on May 12, 2005, 09:49 PM:
Michael-
Sorry about your Sankyo troubles. I wish I had checked this thread earlier. I have two Sankyo ST-800 projectors. One is only for parts because....the sound went out on it!
I can't complain though, since I've had it since 1980 and played it all the time back then. I really got some good milage out of it. When the sound went out about three years ago, I sent it off to Atlantic Camera Repair in New York. After keeping it for about a year, they finally returned it to me and stated that they did not know how to restore the sound. So I just keep it for parts. I purchased a used Sankyo ST-800 after that, and it runs fine.
When the sound went out in my old machine, it had been showing some warning signs- sometimes the sound would just fade out during a run, but piddling with it, I discovered that I could restore the sound temporarily by pressing the "record" button for a few seconds (If you try this, make sure you turn the projector off first, as not to earase your sound track).
Eventually, the sound died and would not return
Unfortunately, I am TOTALLY USELESS when it comes to mechanics, such as fixing machines, projectors, etc., so I can't really help you there.
If you think you can figure any thing out by looking over my working Sankyo projector, you can contact me via E-Mail. I live just over the Wilson bridge in southern Maryland just outside of D.C., and I work in D.C., so let me know if I can assist. Also, you are welcome to any spare parts from my old machine, only I doubt it can help, since it suffers from the same problem.
Nick.
Posted by Jan Bister (Member # 332) on May 12, 2005, 11:11 PM:
Guess what JUST popped up on eBay? A Sankyo Stereo 800, being sold as defective/for parts but with working sound. Maybe this is something that one of you (Rick or Michael) wants to check out.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7515768879&ssPageName=STRK:MEWA:IT
With that out of the way - James, when the sound on your first Sankyo started going out, did it become distorted in a particular way as well? If so, my guess would be that some transistor failed and a replacement should fix that right up. I'm a bit surprised that this Atlantic Camera place there couldn't figure it out, seems it's just down to pure electronics - maybe they were more adept at fixing the mechanical aspects of projectors.
Michael, have a look at the auction as well - there are plenty of good photos of the Sankyo being offered there, maybe you can spot visual differences between the eBay unit and yours? It might help confirm that your unit is (or isn't) indeed slightly different, in regard to non-existent fuses and such. It would really be too bad if your unit couldn't be fixed, so I'm rooting for everyone who's been in this helping you so far - if I knew more about electronic components and how they interact, I would, too - but Rick seems to have that part down pat.
Oh, and one more thing... James, why do you call yourself Nick?
Posted by James N. Savage 3 (Member # 83) on May 13, 2005, 07:22 AM:
Jan- I was wondering if ANYONE was ever going to ask me that .
Actually, my first name really is "James". When the old 8mm forum crashed a couple of years ago and we all had to re-register our names and information, I had my wife fill everything out for me (we always blame the wife, don't we ). When the instructions advised to use your REAL name, she took it quite literally and put my full official name, even though I haven't ever really gone by the name "James", but Nick, from my middle name of Nicholas. I'm only "James" on official paperwork, or in very formal situations. Thanks for asking!
Also, in reference to the sound, the only problem I had prior to it going out was an occassional slight "pop" sound that would happen every 5 minutes or so, usually occurring after an hour of continuous movie showing. This went on for about a year, then the occassional fading, then complete loss.
As I mentioned before, I did put MANY miles on this machine before it did this, so I don't really have a complaint on the Sankyo and would still rate it #2 after the Elmo's.
"Nick" ![[Cool]](cool.gif)
Posted by Rick Skowronek (Member # 385) on May 13, 2005, 09:44 AM:
Guys,
Just a little input on your particular Sankyo sound problems. I presume that you all still had your pilot light lit, meaning the board was getting juice, you were just losing signal somewhere in the sound path. I probably personally serviced well over a thousand tape machines in my early career. The problem you describe Nick is probably due to a dirty, slightly corroded record/playback switch. Since probably one of the least used functions on these projectors is the record, the switches would tend to corrode since no wiping action is going on. Virtually every part of the sound system ends up going through that switch including all playback capability. There are a couple of ways to keep it going better. First with either the projector off or a non-important reel on it move that switch into record 10-15 times. The contacts on the switch will tend to self clean. Also, pickup a can of switch contact cleaner at Radioshack, locate the switch and spray it down. Then move the switch 10-15 times and spray again. This will pretty much restore the switch to like new performance. A regular routine should be that everytime you've played several rolls through it, move that switch a few times.
Another problem that showed up in the 70 and 80s japanese electronics is capacitor dry out. Over time these capacitors would just stop functioning. They are used extensively in the signal path of these electronics. Obviously, that requires some fancy equipment and fairly extensive electronics knowledge. Probably isn't worth fixing unless you do. Can't tell you how many low or no sound problems I traced to those.
Regards.
Posted by Michael Clark (Member # 369) on May 13, 2005, 10:18 PM:
Nick, thanks for the offer!
Jan, thanks for the link - I'll be watching this auction!
Posted by Rick Skowronek (Member # 385) on May 14, 2005, 10:18 AM:
Michael,
As I mentioned a couple of posts ago:
"With that said, you know I'm looking for a projector to get started. Believe me, I haven't lead you astray at any point. Would have loved for it to be something that you could've done. You can kind of blame Sankyo for removing the obviously needed protection that would have saved much of this situation.
If you are going to dump it, please let me know. I would be happy to give you something for the projector and pay for shipping it to me. Obviously, that won't recoup your loss but at least you know it's going to someone who knows what the problems are and will take the risk. Let me know what you think and if that sounds fair. Otherwise, good luck on it and really sorry for the problems caused by a problem lamp socket. Shouldn't have been that disastrous."
Keep me in mind if you do decide to dump it. Also, watching that item. Asked the seller about motor function. He said motor is running just can't find why reels don't turn. Suspect it's more than a bad belt.
Regards,
Rick
Posted by Alan Rik (Member # 73) on May 14, 2005, 10:55 AM:
Or its a belt....and you may have the deal of the century!
Good luck. Hang in there! I had a few problem projectors till I stumbled upon the GS1200. Then again sometimes this one acts strange at times!
Posted by Jan Bister (Member # 332) on May 14, 2005, 12:12 PM:
Maybe we all just ought to go back to Bell & Howell's silent super-8 projectors (the all-metal ones like the model 346), complete with long-play units and our own twin-track magnetic head add-ons
Posted by Kevin Faulkner (Member # 6) on May 14, 2005, 02:36 PM:
I'm sorry Rick that you decided to disagree with me on the forum here. All I was trying to do was help another fellow collector who has a probelm with a projector. Sorry if you obviuosly felt that I was treading on your toes in this matter!!!
Yes I understand what your saying about the lamp etc, but that voltage for the lamp is AC and when it goes on the control board will be rectified to give a DC voltage. If the rectifier has gone open circuit for whatever reason the lamp will still operate correctly but the amp will be DEAD and all associated items fed from that rectifier. A sudden back emf beacuse of the lamp problem could easily take a rectifier block with it.
I would still say that a voltage check at the rectifier and subsequent smoothing cap would be worthwhile before Michael gives up.
I have passed the details onto our resident guru in the UK Bill Parsons for his opinion.
Kev.
Posted by Jan Bister (Member # 332) on May 14, 2005, 03:16 PM:
Very good point Kevin. For what it's worth, I'm inclined to agree that a check of the rectifier is in order before any other steps are taken. There's quite a good chance that's the culprit right there - it just still seems to me like the problem is really a minor one with an easy fix - just locating it is the troublesome part.
Posted by John Whittle (Member # 22) on May 14, 2005, 04:31 PM:
quote:
So I turned the machine off and checked the bulb. I forgot to unplug the machine first, and as I began to loosen the bulb, I heard a pop and sparks flew. Now, there is NO sound, and the smaller, dimmer light under the sound head doesn't work.
Ok, back to basics. After you installed a new lamp the lamp and motor work but no sound or pilot light. One word of caution, when dealing with these projectors, they ARE wired differently for different markets to meet local electrical standards. An Eiki sold for UL/CSA won't be the same as one sold for the UK or Germany, so a schematic and especially fusing will be different. One Eiki, the SL series sold in the US has two fuses on the amp (exciter and amp), the same machine sold under contract to the US military has a detachable power cord and 2 ADDITIONAL fuses on the high and low side of the 117 volt line.
So back to your projector, most machines use an auto-transformer for the lamp since a traditional transformer would be way too heavy to provide the amps at the low voltage, but there are windings for the various other voltages. So we need to get back to the multimeter and see if you have an AC voltage for the amp coming off the transformer and then trace it. It's very likely that a diode could have blow in that instant you heard the pop since the projector was plugged in anything is possible including feeding the high side of the lamp to the chassis and the voltage could have exceeded the input diode on the amp card capacity.
Also, if the projector has a speed control card for the motor, is that running properly? Do you have both speeds? Are the accurate? It could have been a victim of the same thing or if it's ok, then the problem is just on the amp card. Of course many US projectors just used induction constant speed motors and belt changes since the company didn't have to deal with various voltages or Hz rates that were necessary to accommodate in other parts of the world.
I have an Eiki SNT which was built for the international market so it can be switched between 220/117 and 50/60 hz with switches and a motor pulley change. It's wiring is very different from the normal US sold product. (On the other hand, the EX6000 pedestal xenon machines were all built for 117/220 and the supplied pulleys were 50/60 hz).
John
Posted by Michael Clark (Member # 369) on May 15, 2005, 08:22 AM:
Hi Kev!
Where would I find the rectifier and smoothing cap? Are they in the picture at the top of this thread? I might see if I can get a voltage checker - can I find them at any hardware store?
Thanks!
Michael.
Posted by Bill Parsons (Member # 244) on May 15, 2005, 10:27 AM:
Michael and everyone else!
I wish I lived nearer to you Michael, I would be round with a test meter to help you out! Kev passed on the diagram to me to have a look at, it is not clear to me looking at the rather poor copy of the diagram what happens to the lamp common (return) it may well do as Rick suggests, it does appear to be rather an odd arrangement to me, but it does make sense to start at beginning and check the AC into the bridge and DC out, there are only two bridge recs, the one you are looking for is drawn as two double diode units (in one block) wired together in a bridge, that is if we have the correct diagrams for the model you have! Also it is worth checking the underside of the boards for burnt print, this is a strong possibility, you could even have a damaged output ic,it is unfortunate but you do need a bit of technical knowledge to get to grips with this type of fault.
Apologies if I have been over ground that has already been covered, one thing this is certainly creating some interest on the forum, we may end up not talking to each other, but it’s all interesting stuff.
Bill.
Posted by Rick Skowronek (Member # 385) on May 15, 2005, 11:20 AM:
Kevin,
I re-read my post and it does look like I'm a getting testy with you which absolutely was not the case. The more input the merrier. In electronics, as you know, there can be many possible causes to one symptom and certainly a bum rectifier is possible. I was just trying to give, from my perspective and with literally thousands of hours of troubleshooting complex electronics, my best possible theory considering the wiring diagram provided by Mike. It's typically not very likely, though not impossible, for a short circuit spike to get past a close-by ground. The bridge rectifiers in my past experiences can usually take a substantial overload before failing.
That said, without either of us having access to the machine and being able to physically measure anything we're all giving it our best "guess".
Last, just to help Michael, the small black object in his picture of the motor board next to the blue capacitor is a bridge rectifier. I believe from the schematic supplied by Mike that it's the rectifier for the motor voltage. Note: the value of the filter cap on the schematic is 1000uF for the motor. The value of the blue filter cap in his picture is that value. The schematic shows that the filter for the electronics is 4700uF. My deduction was that the bridge and filter for the electronics is on the big sound board under the motor board since the 13.5 VAC is shown connecting directly to the sound card.
One last thing, Michael, if you do pick up an inexpensive multi-meter available at Radioshack to check voltages, just be very careful where you stick their probes. Having done it myself more than once, it's easy to wipe out another component by the probe slipping and shorting something else out.
Good Luck and many apologies again for my Post, Kevin. Wasn't meant to come off sounding harsh and would never want to alienate anyone and especially one with all your experience with these oldies but goodies.
To John Whittle, I agree it's clear that the unit Mike Peckham has is "more" protected than the one Michael is troubleshooting, unfortunately. Just a quick answer on the motor it is a DC unit with tach/generator feedback to a motor control IC. If you need or wish better, clearer shots of the wiring diagram and schematic, I have those that Mike was kind enough to forward to me.
Rick
Posted by Rick Skowronek (Member # 385) on May 15, 2005, 05:51 PM:
Sorry, have to add one more post to this thread then shut my trap.
Bill, I can't believe you're not boarding a flight immediately with trusty multi-meter in hand. Of course the SST is gone so would be a devil of a flight. Me too. I wish I were closer to Michael to flop my own equipment on his problem.
I hope he get's it done reasonably cheap. And does anyone want to make this an even 60 replies?
Rick
Posted by Jan Bister (Member # 332) on May 15, 2005, 08:12 PM:
There.
60.
Happy?
Posted by Jan Bister (Member # 332) on September 10, 2005, 09:00 AM:
Double post... Moderators, please delete...
Posted by Jan Bister (Member # 332) on September 10, 2005, 09:01 AM:
Wow, this topic has been asleep since May... well... Michael, do you still have your Sankyo Stereo-800? Have you tinkered with it any further? Or has it been tucked away in the corner this summer?
Reason for my reviving this thread is an eBay auction I noticed last night. It's one-day only and ends in six hours (I really should have posted here about it sooner!) - as you can guess it's for a Sankyo 800 being offered as a parts/repair machine. The seller says the bulb works (which means power works!!) and everything seems to be in great shape although the reels won't move. This could be a great replacement for your defunct machine, especially if you can take parts from both to make a working unit (should this be necessary).
Just hoping the price doesn't shoot up near the end as it so often does.
Oops! Almost forgot: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7545432743&ssPageName=STRK:MEWA:IT
Posted by Kevin Faulkner (Member # 6) on September 10, 2005, 06:23 PM:
Someone just got a bargain
Kev
Posted by Jan Bister (Member # 332) on September 10, 2005, 07:08 PM:
Yeah, too late now I tried to win but apparently was just a few dollars too shy. Ahwell.
Wonder where Michael is, though...
Posted by Osi Osgood (Member # 424) on September 12, 2005, 11:40 AM:
Hey, Jan, Osi here, (duh, It's right above the post!!) Could you write me as I lost your address to write to you. Did you recieve my reply?
all the best
Posted by Jan Bister (Member # 332) on September 12, 2005, 09:23 PM:
I did, and my email address is right in my user profile which you can view by clicking on my name here on the forum.
Posted by Jan Bister (Member # 332) on February 07, 2006, 10:26 PM:
Gentlemen, (and ladies?)
well, shortly before Christmas I bought the Sankyo 800 from Michael Clark... relieving him from a potential boat anchor and giving me another project to do...which I'm finally getting around to now. Having just re-read the whole thread from the beginning, I'm now armed with a wealth of info and some good starting places to check out with a multimeter... A few questions I do have, though:
1. Whoever has the high-resolution scan of the wiring diagram (the one that Mike Peckham emailed to Michael Clark), could you forward a copy to me via email (jbister at neo dot rr dot com) please?
2. There are supposed to be 3 fuses in the projector.... now we've established that this particular unit is missing the sound board fuse (actually it looks like someone took it out and soldered a short piece of thick wire in its place! I wonder...) - but where are the other two fuses supposed to be located? I cannot seem to find any. Then again, however, I've yet to take the machine further apart to get a better view of things. Are they hidden somewhere inside? Near the power transformer?
Thanks in advance
Posted by Jan Bister (Member # 332) on July 02, 2006, 12:09 AM:
This topic is continued here:
http://8mmforum.film-tech.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=001730
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