I recently purchased a used Dwin HD700. The seller informed me that all three CRTs were replaced by Dwin and then the unit went into storage for a little over a year before I bought it. So the CRTs are new and unused. The picture looks really good but the set, which is touted as being silent, emits several sounds -- the yokes on all three CRTs buzz, a cooling fan below the lenses sounds a little rough, and most annoyingly of all, the projector emits a constant crackling sound. It's almost like the normal electric crackling sound you hear when you turn on or off any CRT monitor. But uunder normal circumstances the sound goes away after the tube fires up. In my case, the crackling continues unabated for as long as the projector is on.

The crackling seems to be coming from the vicinity of the anode caps on all three CRTs. I've looked closely in a dark room and I can't really see any visible arcing. I talked to a technician at Dwin which was very difficult. I actually had to go to their small store in Burbank because they would not return phone calls or answer emails. This technician said the crackling was normal for new tubes and that it would go away on its on after a few weeks. It's been over three months and the crackling has not dissipated at all. The crackling seems to get a little louder after the projector has been on for a long time. I attempted to recontact Dwin, but again they have not responded. Their extremely poor customer service is reason enough by itself to stay clear of Dwin products.

The inside of the projector looks very clean and well maintained. No obvious grime or frayed wires. The HV leads look good. What could be causing this sound and will it go away on its own? I've read on other posts that it may be the HV leads are leaking. However since the sound is coming from all three CRTs, I would think its unlikey that all three HV leads are bad.

Any advice would be greatly appreciated. I bought the Dwin specifically because it's supposed to be virtually silent, but that is unfortunately not the case with my projector. Between the audible fan, the buzzing yokes and the crackling, I'm getting to the point where I may have to junk the set. It would be a shame because the picture looks good but I find the noises, especially the constant crackle, too distracting to enjoy using the projector.

Thanks in advance for any info.

Bruce Taylor

Why not try adding a nice thick coating of silicone to the area where is sounds like you are experiencing arcing ? There might be a tiny, tiny break in the anode cap seals ?

Disconnect the HV lead at the HV transformer at the front of the set and see if the crackling goes away. If not, the HV power supply is bad, which is encased within the whole front power supply. If it stops, disconnect all HV leads from the HV splitter and see if it goes away. If it does, then you may have bad HV leads.

I've had a few DWINs through here, they don't crackle.

I have spare parts for them...

Thanks for the input. However, I'm not really sure I understand. Since the crackling is definitely coming from the CRTs, wouldn't disconnecting the HV leads cause the CRTs to receive no power and therefore by definition they would not crackle?

Well in theory yes, but I did want to narrow the possibilities down further.
:)

You're probably right about it being the HV leads. There really aren't a lot of other posssibilities. I was thinking that maybe the leads could have been installed incorrectly when the CRTs were changed. Perhaps if I disconnected and then reconnected with new silicone that would help. If not, then I guess the next step would be to change the leads. One thing that is strange though is that the crackling seems to get louder after the projector has been on for an hour or so. If the leads were bad or the connection, would the crackling get worse the longer the projector is on or should it be constant? Once in a while, the projector doesn't crackle at all until after it's been on for fifteen minutes or so. Thanks for all the advice.

I was thinking that maybe the leads could have been installed incorrectly when the CRTs were changed.

I would bet money on it.

One thing that is strange though is that the crackling seems to get louder after the projector has been on for an hour or so.

When the PJ gets warm, parts can expand or flex slightly, which could account for the change in sound.

Is it possible that the G2 voltage was set too high when the CRTs were replaced and as a result some of the HV is leaking at the anode caps and causing the crackling? I was thinking of trying to lower the G2 voltage but the controls have been silconed in place. I could easily remove the silicone but I don't want to attempt it unless someone with some knowledge thinks that it may work.

Nope, that's not it. Don't break those seals, they are sealed for a reason..

Curt, I read a post of your somewhere that said you thought Dwin may be going out of business. Did you ever find out if that's true? I think they may be closing down because they've stopped answering their phone and returning emails.

I believe they are still doing repairs, there's a thread about it on my forum. Sounds like they come in twice a week, but how long can a company last doing business like that?

The Dwin that I had crackled as well...and I recall hearing this from more than one other DWIN owner. I suspect it's part of most Dwins, maybe room environment plays a role...

Ben

DWIN HD700 projectors are KNOWN to make the crackling sound so before you start taring into it looking for problems just know they do this.

I have a HD 700 with a little over 1000 hours and it still makes the crackling sounds. Its subtle and not that bad at all and sometiems its quite "nice" to hear those sounds :) . I mean if you have sounds like pops and snaps like an M80 going off then Id get inside and see what is wrong.

YOU SAY BRAND NEW TUBES well, Any and all NEW crts will crackel quilte a bit and thats perfectly normal as they are breaking in. SO that does sound to me like new tubes.

Fan noise well, that sucks becuase the only way I know my DWIN has a fan in it is because Ive actually seen it in the power supply. If you never knew there was a fan in the HD 700 you would suspect it didnt have one thats how dead silent my projector is. You can either replace the fan or try lubing it up. I wont go into details on how to lube the bearings as most of the techs will just shoot my ideas down so Ill leave you to figure it out. Like I say its problably easier to do a fan replacement then anything since the power supply can come right out and you can work on it easiy enough.

The DWIN is an amasing projector once you set it up and calibrate it. Forget that its a 7 inch projector. It does more then what most people can get out of a 7" projector once set up right.

Also the video cabeling internally NEEDS to be swapped out to REAL RGBHV MINI cable as the stock wire is terrible. I did the video mod and after I did this my projector beat the snot out of another "local well tweeked" HD 700.

The mod is easy if you know how to solder if your not good then dont try as its pretty tedious and quite "tight quarters" when moding the molex connector.

One of the easiest things you can do to improve STOCK HD700's is to put color filtered lenses on this machine. NIGHT AND DAY is the best way to describe what true 720p looks like on the DWIN HD700.

Once you see a true calibrated 720p HD700 youll ask your self why do I need 1080p? the answer is, you dont!
Now there is a solution out there to allow HDMI over RGBHV and Im woundering how the dwin would do with HDMI feeding it......Something I need to look into possible..........My HD700 did sync to 1080p via RGBHV but I didnt want to run it too long that way as I was afraid someting bad would happen.

Jeeeeez do I sound like the old Steve B?

DWIN HD700 projectors are KNOWN to make the crackling sound so before you start taring into it looking for problems just know they do this.

I have a HD 700 with a little over 1000 hours and it still makes the crackling sounds. Its subtle and not that bad at all and sometiems its quite "nice" to hear those sounds :) . I mean if you have sounds like pops and snaps like an M80 going off then Id get inside and see what is wrong.

YOU SAY BRAND NEW TUBES well, Any and all NEW crts will crackel quilte a bit and thats perfectly normal as they are breaking in. SO that does sound to me like new tubes.

Fan noise well, that sucks becuase the only way I know my DWIN has a fan in it is because Ive actually seen it in the power supply. If you never knew there was a fan in the HD 700 you would suspect it didnt have one thats how dead silent my projector is. You can either replace the fan or try lubing it up. I wont go into details on how to lube the bearings as most of the techs will just shoot my ideas down so Ill leave you to figure it out. Like I say its problably easier to do a fan replacement then anything since the power supply can come right out and you can work on it easiy enough.

The DWIN is an amasing projector once you set it up and calibrate it. Forget that its a 7 inch projector. It does more then what most people can get out of a 7" projector once set up right.

Also the video cabeling internally NEEDS to be swapped out to REAL RGBHV MINI cable as the stock wire is terrible. I did the video mod and after I did this my projector beat the snot out of another "local well tweeked" HD 700.

The mod is easy if you know how to solder if your not good then dont try as its pretty tedious and quite "tight quarters" when moding the molex connector.

One of the easiest things you can do to improve STOCK HD700's is to put color filtered lenses on this machine. NIGHT AND DAY is the best way to describe what true 720p looks like on the DWIN HD700.

Once you see a true calibrated 720p HD700 youll ask your self why do I need 1080p? the answer is, you dont!
Now there is a solution out there to allow HDMI over RGBHV and Im woundering how the dwin would do with HDMI feeding it......Something I need to look into possible..........My HD700 did sync to 1080p via RGBHV but I didnt want to run it too long that way as I was afraid someting bad would happen.

Jeeeeez do I sound like the old Steve B?


Yes you are c(r)ackling like Steve B when his Dwin worked for 6.5 years before breaking down twice and being replaced by a Sim2 C3X 1080. The Dwin gave me mucho enjoyment in its time.

Crackeling like Steve LOL....Thats funny!


Hope your system is working great steve......I have to call about those grills I forgot! Ill do it today!

Crackeling like Steve LOL....Thats funny!


Hope your system is working great steve......I have to call about those grills I forgot! Ill do it today!

Vic, the 10.5' wide 2:35 curved screen with the Siim2 C3x 1080 is just wonderful, like looking through a squeaky clean window without the window!!!!
Brighter yet more natural than the best movie theater whether analog or the latest digital projector (just saw that the other day for The Incredible Hulk at the Cine Capri in Tempe, and that was awesome for the theater, I can only imagine what it'll be like in my theater).

I luved my Dwin in its time. But the video improvement in going from a 2:35 CRT 80" wide to a 3 chip DLP 10.5' wide 2.35 is nothing short of staggering!!!@@@

Thanks for the reply.

Okay, so maybe it's normal for new tubes to crackle. Does anyone know the technical reasons why they crackle?

Also has anyone had any excperience with applying lacquer or crazy glue to the yokes to stop the buzzing sound?

I hear a buzz here and there on very bright scenes so I dont know if yours do it all the time or not. Could be that your brightness it way up too high.

I just re tweeked mine last night.

The crackeling I beleive is just from the new electron guns being so strong creating static electricity inside the projector. You get some dust particals around the tubes being sucked on to the glass and makeing some small crackeles...Also NEW phosphors heating up and burning in (more like breaking in ) for the 1st time will make some noise.

Just the sounds of how a CRT breaks in. It does tend to get a little subtle and after a while you wont here it as much. I dotn beleive I hear my crackles a smuch as I did when I 1st put in my DWIN.. Seems if I dont use my projector for long periods of time I notice it more. It might be just me though.

Thanks Victor,

My projector buzzes all the time. It's the kind of buzz you might hear from a transformer or flourescent light. It's coming from the copper coil on the yokes of all three CRTs. I've attenmpted to apply pressure to the copper coils in hopes that the buzzing was some kind of vibration that could be corrected. Howver, no matter where I press or how hard, it does not affect the buzzing. I've heard this buzzing yoke sound on other CRTs but not all of them so it must not be inherit in the technology itself.

The crackling is some kind of static discharge sound. The crackling is constant after the projector has been on for about twenty or thirty minutes. The crackling used to start the moment the projector was turned on but now there is a slight delay. If it is the electron gun being so powerful because it's new, why don't other projectors make this sound? I don't think dust is being sucked in and causing the crackling because as I said, it takes about twenty minutes or so for the crackling to start. Once it does start, it is constant and seems to get a little louder the longer the projector is on. You said yours still crackles. How long have you had it. A technician at Dwin once told me the sound is normal and would go away after a couple of months. It has not. Others on this board have reported that their Dwins also crackle. For a projector that touts itself as totally silent, I would say this is a real problem.

I hate Dwin. I'm glad they're out of business. They are a real second rate company.

"I hate Dwin. I'm glad they're out of business. They are a real second rate company."

Naah there's a ton of happy Dwin post owners and present owners. I have two, my first HD700 went to 12000 hours before the power supply finally went out. My present HD500 has 2000 hours and has alway performed perfecly. Just another happy Dwin owner, I just like the light weight and small foot print of the machine. I use the CRT as the work horse in my multi projector systems. Great little projector.

Tom,

Did any of your Dwin projectors make the crackling sound I posted about?

I am a happy HD700 owner. In fact I have had two of them. I had my first one for about 6 years until both the lenses and main board blew. I did not get satisfactory service from Dwin when I sent it back to be repaired so I bought a second used HD700 from a very reliable source and I am keeping my first one for parts.

Both units have always had a slight crackling sound. The sound was however a little quieter on my second unit than my first, but they were both tolerable. The fan however has always been inaudible. In this regard the HD700 has been super quiet.

Femi Lakeru.

Thanks for your post Femi,

Are you saying that your first Dwin crackled for the entire 6 and a half years? Right before they went out of business, a service tech at Dwin told me the crackling was normal for new CRTs and it would go away after a few months. Do you have any idea why it crackles? It's somekind of static electricity discharge but I don't understand why no other CRT projectors have this problem. I've owned several different brands -- Sony, Runco, Harmon Kardon -- none of them made any crackling sound at all. It's a little ironic that the Dwin is touted as the silent projector and yet it makes this annoying sound that no other projector seems to make. I prefer the Sony's fan noise to the crackling. I wish there was some way to make it stop.

Thanks

I've got a Dwin HD700 I'm working on for a friend that has an intermittent red gun. Wondering if anyone knows anything about this, which he says may be a known issue. He says it definitely goes out periodically, though I've not been able to duplicate the problem even after running it for a few hours (i.e., may not be a thermal-related part failure). Few years ago he had another buddy call Dwin, and a tech talked him through an apparent mechanical issue with one of the connections, but the symptom has come back. Anyone have any experience with this?

Thanks,
Rob Sabin

Trend I've spotted with failed Dwins...especially after shipping back for repairs...is that one brass faraday shield's tabs always break at the circuit board mounting.

Edward put it there for a purpose, it is a mighty expensive addition to his cost-cutting genius...and every one that failed repeatedly had broken tabs.


I wanted to experiment rebuilding and grounding 'em, but my unfortunate extended sabbatical got a wee bit in the way. I've got a 500 and 700 here just awaiting some spare time...ahem.


Just look at that one huge board that is perpendicular to the main board...both tabs should be solid but if you shipped it back to Dwin I guarantee they are broken and you WILL have trouble with the unit.


NO, I don't know why...I am only the tweak not an engineer. I spot the trends, someone else can explain them.


Cheers!

Robo,

That sounds like tarnished connections where the CRT drive board plugs into the back of the gun.

They can react differently when heated, like any good dialectric (even when unwanted)!

Check ALL of Curt's excellent warnings before touching any of that stuff!

Cheers

Thanks much, John! Wouldn't have known where to start looking. I'll see if I can find any of Curt's postings to read the warnings of which you speak.

Rob

Okay, I'm making my way around this projector now, so here's another coupla quick Q's for anyone out there who can help.

This projector has an original TranScanner attached to it for line doubling and input selection, but it's been strictly used for an S-video feed from a receiver until now. Far as I can tell, the projector has never been used for HD playback (don't ask :rolleyes:) I've now hooked up an HD cable box via component input, and the Transcanner is seeing the signal just fine in 480i. But setting the cable box output to any other format including 480p causes multiple screens to appear. I can't get it to sync up on any HD or progressive scan signal. So now my questions:

1. Is the original TranScanner HD capable? Can't find documentation on this piece anywhere.

2. If so, where in the menu system can I make an adjustment so it's happy seeing HD?

3. Anyone got the component code for resetting the original SL8000 to operate the TranScanner. The manual for this piece is not on the Dwin website, and needless to say, getting anyone at Dwin to pick up the phone at this point is impossible. I haven't been able to get into the Display submenu because my remote's not working. (sigh...)

Thanks!

Rob Sabin

The component input on the Transcanner probably cannot even see a line-doubled DVD output, so you're way overloading it with HD.

You'll have to get a transcoder, like the Key Digital, to go from component to RGB (HD-15 type plug) and use the pass-through.


Everything was in transition back then...the good old days.

I'll look up that remote code today, I've got the manual around here somewhere.

I'm still sorting...

Tom,

Did any of your Dwin projectors make the crackling sound I posted about?


No crackling noises, but we did talk about insulating the wires in the power supply because a member was getting crackling noises. Maybe you can search out the past thread, which has pictures on how to do it. His crackling noise was an arcing from the insulator to the case ground in the power supply.

Thanks, John. I got the TranScanner code needed to reprogram the original factory remote URC SL-8000 -- it's 009 for anyone's future reference. (Press AUX and MUTE simultaneously; SET appears in the LCD, enter 009, press AUX).

And thanks for the clarification on the unit's capabilities. I'll look into a converter box of some kind. Glad to know I wasn't crazy -- at least about this!

Robo

Thanks, John. Just responded to this post but I'm not sure where my reply went, so sorry for any redunancy here. But I found the component code for reprogramming the TranScanner's original URC-SL8000 factory remote -- "009" for anyone's future reference. Programming sequence is: Press AUX and MUTE simultaneously (SET appears in the remote's LCD); enter 009; press AUX to complete programming.

And thanks for the clarification on the TranScanner's component input. I'll look into getting an component-to-RBG converter. As I just noted in my errant post: good to know I'm not going insane, at least about this! :)

Everyone that I installed in the past has crackled. Some more than others. Static was always deemed as the culprit.
I have a HD 700 sitting here that I would like to get out of my wharehouse. It was taken out of a clients house when he suffered flood damage. I replaced it with a DILA projector and it has just been sitting in the back here for a few years. Let me know if interested.....
richard@area51audio.com