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"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 24 07:05PM +0100 "N_Cook" <diverse@tcp.co.uk> wrote in message news:n0fb26$ld$1@dont-email.me...   > If there is no dusting or latent image on the drum/transfer sheet, when > halting the machine mid-cycle and opening up, then failed corona generator > perhaps   That would be my guess - AFAICR: the laser discharges the static charge on the photoconductive film at the points where no toner should be attracted to.   I think a failed laser would result in a completely black page, maybe the transistor that drives the laser going leaky - but that's in a critical constant current loop, a leaky transistor would probably destroy the laser.

Jeff Liebermann <jeffl@cruzio.com>: Oct 25 12:32AM -0700 >just powdered toner and smear easily. Not so.   >Lots of toner. Still, I took out the cart and shook it around and >reinstalled. No joy.   If it faded like that, I would guess(tm) that you're out of toner. Try a different or new toner cart anyway.   Also, I've seen the shutter mechanism jam or break on the toner cart or at the entrance slot to the laser scanner. Play with the toner cart mechanism and see if the protective shutters are operating normally.   Just for grins, try a test page from the printer, not the computah. If the test page works, look for computer problems.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

DaveC <not@home.cow>: Oct 25 01:00AM -0700 On 24 Oct 2015, Ian Field wrote   > I think a failed laser would result in a completely black page, maybe the > transistor that drives the laser going leaky - but that's in a critical > constant current loop, a leaky transistor would probably destroy the laser.   Any idea the approx voltage of the corona wire? I could check, but it would be nice to know if it's 300, 600, 1000?   Thanks.

N_Cook <diverse@tcp.co.uk>: Oct 25 08:17AM On 25/10/2015 08:00, DaveC wrote:   > Any idea the approx voltage of the corona wire? I could check, but it would > be nice to know if it's 300, 600, 1000?   > Thanks.   More like 2,000 to 5,000V. The generator is often a selfcontained unit off 28V or so, with just an on/off control line. Flop a 100M resistor to the corona wire and insulated lead out to a neon bulb to frame , in the first instance.

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 25 04:34PM "N_Cook" <diverse@tcp.co.uk> wrote in message news:n0i331$k8r$1@dont-email.me... > 28V or so, with just an on/off control line. Flop a 100M resistor to the > corona wire and insulated lead out to a neon bulb to frame , in the first > instance.   Pretty sure I've seen one at 6kV, most were somewhere around the 5kV mark.   Some older types are pretty sturdy and can give a nasty nip. Unlikely to be as dangerous as microwave oven innards, but I still wouldn't bother sticking my fingers in there!

jurb6006@gmail.com: Oct 24 11:13PM -0700 So now, with the coveted volume two in hand, I see they call the vertical horizontal and the horizontal vertical. The print does depict what I had been reverse engineering. I think on page 7-249.   The vertical circuit does not use a boost cap, switcher or diodes as far as I can tell. Simple transconductance (current) amp run off a ramp.   It has vertical foldover, that is usually caused by not enough voltage peak on retrace. In an old TV it would almost certainly be a bad lytic. But this does not use that type of circuit.   Actually it might be a bit of fun doing this. I have to put leads on the board to test it because it is shielded. What's more, the way it is I have to use insulated wire. Alot of times I have just used solder, but that won't work with this.

Ken Layton <KLayton888@aol.com>: Oct 24 12:33PM -0700 > Cylindrical. Axial leads.   > Ordered caps for a speaker crossover because the leads had literally been shaken out of the originals. But I had no luck finding those bulbs. I would rather not jump it out. I guess I could and just put a beefier horn in it.   It's called a "barreter". It's just a lamp used as a current limiter.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Oct 25 08:39AM +1100 > been shaken out of the originals. But I had no luck finding those > bulbs. I would rather not jump it out. I guess I could and just put a > beefier horn in it.   **Select an appropriate sized Polyswitch™. Cheap, reliable and effective.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Gareth Magennis" <sound.service@btconnect.com>: Oct 24 10:49PM +0100 "Trevor Wilson" wrote in message news:d92c5nF8av2U3@mid.individual.net...   > been shaken out of the originals. But I had no luck finding those > bulbs. I would rather not jump it out. I guess I could and just put a > beefier horn in it.   **Select an appropriate sized Polyswitch™. Cheap, reliable and effective.           Polyswitches are not compressors.       Gareth.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Oct 25 10:58AM +1100 On 25/10/2015 8:49 AM, Gareth Magennis wrote:   > Polyswitches are not compressors.   **Correct. They're much better. They protect drivers, without significant audible problems (like compression).     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Gareth Magennis" <sound.service@btconnect.com>: Oct 25 01:54AM +0100 "Trevor Wilson" wrote in message news:d92kb7Fa87iU3@mid.individual.net...   On 25/10/2015 8:49 AM, Gareth Magennis wrote:   > Polyswitches are not compressors.   **Correct. They're much better. They protect drivers, without significant audible problems (like compression).             Do you think you would be able to hear such a compression problem?     Gareth.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Oct 25 02:23PM +1100 On 25/10/2015 11:54 AM, Gareth Magennis wrote:   > Do you think you would be able to hear such a compression problem?   **Absolutely. I've proven it, under blind test conditions, to clients who own speakers that are equipped with such things.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Phil Allison <pallison49@gmail.com>: Oct 24 09:10PM -0700 Trevor Wilson wrote:   > **Select an appropriate sized Polyswitch(tm). Cheap, reliable and effective.   ** Polyswitches are not a good alternative to low voltage lamps with horn drivers in systems used for sound reinforcement.   Biggest problem is the sudden switch off of the horn and long wait for it to come back on - this is unacceptable to performers or audiences.   OTOH, correctly chosen lamps act immediately - reducing the over power condition to a safe level for the horn driver and then recover almost as fast.   Many active systems use limiters that do the same job.     ... Phil

jurb6006@gmail.com: Oct 24 09:54AM -0700 Somewhat like the people who leave their stereo at flat response. the bass and treble controls are there to be used. Every recording is not perfect and every speaker is not perfect, especially in a real room.   How the shoot these new movies and shows annoys me. Color effects, the blacks are green or whatever. And I know it is them because if you turn the color all the way down you have a good greyscale. Camera angles shifting like a damn toddler had the camera.   And geometry ? Either it is letterboxed, cropped on the sides or overscanning because they haven't gotten their aspect ration shit together.

thekmanrocks@gmail.com: Oct 24 11:40AM -0700 > Somewhat like the people who leave their stereo at flat response. the bass and treble controls are there to be used. Every recording is not perfect and every speaker is not perfect, especially in a real room.   > How the shoot these new movies and shows annoys me. Color effects, the blacks are green or whatever. And I know it is them because if you turn the color all the way down you have a good greyscale. Camera angles shifting like a damn toddler had the camera.   > And geometry ? Either it is letterboxed, cropped on the sides or overscanning because they haven't gotten their aspect ration shit together.   ___ Actually jurb, the default TV settings are like having the bass & treble jacked fully clockwise, or the graphic equalizers set like smileys - middle sliders down, and sliders toward the ends higher and higher.   As far as aspect ratio is concerned, 16:9 or "screen fit" will accommodate most viewing scenarios. I'm really annoyed by those who insist on stretching 4:3(old fashioned TV) pictures to fit their wide-screen HD theater, so J.J. from "Good Times" looks wider than superintendent Bookman. LOL!

stratus46@yahoo.com: Oct 24 11:18AM -0700 On Thursday, October 22, 2015 at 3:05:38 PM UTC-7, Percival P. Cassidy wrote: <snip> > or donate a working monitor to the thrift store/charity shop (whichever > term you use where you live) than simply trash it.   > Perce   Older LCD monitors use CCFL (Cold Cathode Fluorescent Lamps) for backlighting and these wear out like any other lamp. Capacitors also go bad FREQUENTLY. There are 'kits' ($15 to $20) to convert CCFL to LED backlighting and I have successfully converted several monitors to LED but it requires above average knowledge. The panel gets disassembled down to individual layers in the backlighting, possible mechanical mods to accommodate the new power module and getting the 12-30 Volt power source into the new power module.   The monitors I did this to are in rack mount drawers with keyboard and track pad so the time was worth it to salvage these expensive units. For home use that's your call and with 24" units on sale for $100 it may not be worth the time unless you want the 'education'.   G²

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