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John Robertson <spam@flippers.com>: Feb 26 09:43PM -0800 >> Thanks,   >> John :-#)#   > You said it "has a jitter on the horizontal lines on the screen (vertical is locked)". Just want to be clear. Do you mean to say the horizontal lines from the generator are jittering up and down indicating a vertical problem?   The monitor has had all electrolytic capacitors replaced, along with most of the mylar ones.   We use Panasonic caps for electrolytics.   No, the lines are jittering sideways - indicating a horizontal problem. If I adjust the horizontal control the jittering stays much the same as the picture shifts sideways until it loses the lock.   John :-#(#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

John Robertson <spam@flippers.com>: Feb 26 02:06PM -0800 I have an older monitor from a video game - and it has a jitter on the horizontal lines on the screen (vertical is locked), yet I don't see this jitter on the H Sync. Using a signal generator (Cross-Hatch, Dot, etc.) and all outputs are the same. Game source also shows same jitter on same screen.   It is not the WICO monitor signal generator as other B&W monitors show a locked image.   Schematics here:   http://www.flippers.com/pdfs/TEC_TM-600_TM-623_Monitor.pdf   Monitor has been recapped. Horizontal does lock, but jitter still present.   Suggestions appreciated!   Thanks,   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

ohger1s@gmail.com: Feb 27 03:13AM -0800 On Monday, February 27, 2017 at 12:44:01 AM UTC-5, John Robertson wrote: > If I adjust the horizontal control the jittering stays much the same as > the picture shifts sideways until it loses the lock.   > John :-#(#     I wonder if you're describing what we used to call "piecrusting". Most of that was was from leaking HV. Remove the HV rectifier and see if there's any green schmutz in the contacts. Any corrosion will cause arcing.

micky <NONONOmisc07@bigfoot.com>: Feb 26 05:04PM -0500 In sci.electronics.repair, on Fri, 24 Feb 2017 15:53:52 -0600,   >I have never had any of them get hot or cause any problems at all. I did   I don't think I had had that either, which is why I posted. Of course maybe I'd never left it on so long before.   >have a few with switch problems, but very few. Since I have plenty ones   I don't have as many as you, I've had maybe 10 total and 2 or 3 have had the switch fail after very few uses. I expect the others to fail any minute....   That's caused me to think, Don't wear out the switch, leave it on, And that's what led to my leaving it on when I put it in my pocket!   Which might be the only reason it was warm.

bitrex <bitrex@de.lete.earthlink.net>: Feb 27 12:55AM -0500 On 02/25/2017 09:28 AM, N_Cook wrote: > Hopefully that means the 74LS138 3 to 8 demultiplexer did not survive > 1/3 century,internal metalisation creep or something, rather than main > micro problem.   Did you try doing a factory configuration reset? These old Rolands use a battery backed SRAM to store both patch data and for the system scratchpad RAM, if it gets corrupted you can get all sorts of problems like the ones you describe.

bitrex <bitrex@de.lete.earthlink.net>: Feb 27 12:58AM -0500 On 02/27/2017 12:55 AM, bitrex wrote: > battery backed SRAM to store both patch data and for the system > scratchpad RAM, if it gets corrupted you can get all sorts of problems > like the ones you describe.   That is to say it stores front-panel settings etc. in the battery backed RAM during power-down, and if they get corrupted to garbage values the keyboard stops triggering correctly, etc.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Feb 26 07:19PM "N_Cook" wrote in message news:o8s467$88f$1@dont-email.me...   Stored indoors for some years and then powering up, missing notes and some top panel sw functions missing. full sm here http://www.synfo.nl/servicemanuals/Roland/JX-3P_SERVICE_NOTES.pdf same 2 notes ,not each octave , but as keyboard is scanned as 8x8 matrix keys 8n and 8n-2 are missing , n= 1 to 8. Hopefully that means the 74LS138 3 to 8 demultiplexer did not survive 1/3 century,internal metalisation creep or something, rather than main micro problem.     ******************************************************       It is more likely dead VCF chips, IR3109.   Scope around this area and see if they have any input/outputs.     It will not be a uP problem.     Gareth.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Feb 26 07:17PM "N_Cook" wrote in message news:o8s467$88f$1@dont-email.me...   Stored indoors for some years and then powering up, missing notes and some top panel sw functions missing. full sm here http://www.synfo.nl/servicemanuals/Roland/JX-3P_SERVICE_NOTES.pdf same 2 notes ,not each octave , but as keyboard is scanned as 8x8 matrix keys 8n and 8n-2 are missing , n= 1 to 8. Hopefully that means the 74LS138 3 to 8 demultiplexer did not survive 1/3 century,internal metalisation creep or something, rather than main micro problem.     ******************************************************       It is more likely dead VCF chips, IR3109.   Scope around this area and see if they have any input/outputs.     It will not be a uP problem.     Gareth.

clare@snyder.on.ca: Feb 26 08:31PM -0500 On Mon, 27 Feb 2017 10:28:45 +1100, Chris Jones   >I've read that the goop that they supply instead of a spare wheel will >ruin the tyre every time, and that seemed an unacceptable waste to me. >Also as you point out, the goop won't fix a really big hole.   It won't fix a cracked valve stem either -

clare@snyder.on.ca: Feb 26 08:36PM -0500 On Sun, 26 Feb 2017 18:35:19 -0500, Ralph Mowery >for many miles and if out of town hard to find one.   >I did see a small car driving around town and I am sure they had 4 of >the 'small spaires' on it. It's a real bugger if you blow a rear tire on a RWD vehicle with Limited Slip too. You have to take off a front tire and put the spare on there, then take off the flat rear and replace with the front - and from the same side if you have directional tires. Can't carry a "matching" tire for a spare that way either and leave it on....Which is part of the reason they went the "no spare" route.   I know guys who's cars have sat at the dealers or the tire shop for a WEEK waiting for the right tire to be couriered in from Kentucky or Florida to Ontario because there was none closer (one was a Mercedes)

Ralph Mowery <rmowery28146@earthlink.net>: Feb 26 10:21AM -0500 In article <o8uduv$qa3$3@dont-email.me>, ham789@netzero.net says...   > You're never gonna need one...until about a week after you > dispose of it. > Better to have and not need than to need and not have.     That is the way it is for everything. I worked at a plant that was built about 1965. At that time there was a spare part that looked like a big auger. It was about 10 feet long and a foot in diameter. It laid around in the way up to about 2005. We got a new plant manager that had us get rid of all things we had not had to replace in the last 5 years. Out went the auger. Wouldn't you know it , a month later it was needed to replace a bad one. Same as with another piece of equipment . I forgot what it was, something like a 20 HP motor and gear box. It was sold as scrap. Before it left the plant site it was needed and we had to buy it back for a lot more than it was sold for.   I have not seen it, but heard that some new cars do not even have a spare tire now,but come with a can of Fix a Flat. Might be fine for a nail hole, but if there is a large cut in the tire,itwill be useless.

Phil Allison <pallison49@gmail.com>: Feb 26 10:56PM -0800 Foxs Mercantile wrote:   > Another thing to keep in mind, wire wound resistors have inductance. > Although probably not enough to become a substantial issue at audio > frequencies.   ** Typical hollow, ceramic WW resistors rated at 100W show no change in value until the frequency is well over 100kHz.   The metal encased sort that need a heatsink show much less.   Inductance in WW resistors sometimes becomes an issue with very low values - like 0.1 ohms.       .... Phil

mike <ham789@netzero.net>: Feb 27 12:42AM -0800 On 2/26/2017 4:49 PM, Phil Allison wrote:   > ** Wrong - you get a 6.25ohm resistor IF the slider in centralised.   > There are then two, 12.5 ohm sections in parallel.   > .... Phil   Yep, brain fart on my part.

Phil Allison <pallison49@gmail.com>: Feb 27 12:59AM -0800 Phil Allison wrote:   > ** Typical hollow, ceramic WW resistors rated at 100W show no change > in value until the frequency is well over 100kHz.   ** The above applies to resistors of 4 ohms resistance, or greater.   The trick is that for a given physical size, inductance values do not vary that much while resistance values vary over a range of 1,000,000:1.     ..... Phil

"Michael A. Terrell" <mike.terrell@earthlink.net>: Feb 26 10:17PM -0500 > thousands of watts range. But to use that kind of tube would require > custom output transformers that would likely mimic the pole transformers > used to feed our homes....     A pole pig would wave been useless, since they weren't designed to pass DC, and they aren't center tapped on the primary. On top of that, they would have a horrible frequency response, because they were designed to operate at 60Hz.   A 25KW, plate modulated AM transmitter would produce 12.5 KW of audio but you would have needed to a hundred amps of three phase 480VAC to power it. Something I doubt that was available on that farm, or from portable generators. You could move the modulator from a 5KW AM transmitter, but the modulation transformer weighed over a ton. We had to abandon one from a Gates transmitter that was bought from WQBQ for spate parts. Sadly, it was only a couple years old, and one of the premium replacements from Peter Dahl.   > conflict whether it was 3,500W or 12,000W. > Either way, that PA system had to cover a very large area, and > apparently it did the job.     Those Mcintosh amps were not designed for that type of service.       > http://www.mylespaul.com/forums/showthread.php?t=100811   > These Mcintosh MC3500 power amps have EIGHT power output tubes > 6LQ6/6JE6B. These amps had an output of 350W. (mono).   The RCA TTU-1/TTU-25 UHF TV transmitters used 16 6146 tubes in parallel for a video amp with a response from DC to over five MHz. It was a 'Distributed Amplifier'.     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

oldschool@tubes.com: Feb 27 01:39AM -0600 On Sun, 26 Feb 2017 22:17:57 -0500, "Michael A. Terrell" >pass DC, and they aren't center tapped on the primary. On top of that, >they would have a horrible frequency response, because they were >designed to operate at 60Hz.   Thats right, no center tap.... Back to the drawing board :)     >to abandon one from a Gates transmitter that was bought from WQBQ for >spate parts. Sadly, it was only a couple years old, and one of the >premium replacements from Peter Dahl.   Too bad you abandoned that transformer. You should have rented a skid loader or farm tractor with a loader. My 1959 farm tractor, which is small compared to modern ones, lifts round bales of hay all the time. They weight anywhere from 650 lbs to 1800 lbs. It struggles on those 1800 lb ones, but a larger tractor could easily handle a ton or more. (I dont buy or make bales larger than 1500 lbs).   >> Either way, that PA system had to cover a very large area, and >> apparently it did the job.   > Those Mcintosh amps were not designed for that type of service.   I thought that same thing, but they apparently can and did handle that abuse, The Greatful Dead,"Wall of Sound". Was entirely run from Mcintosh MC3500, Tube amps, and the MC2300 solid state amps, having a total of around 28,000 watts. Not the intended use, but they held up....     > The RCA TTU-1/TTU-25 UHF TV transmitters used 16 6146 tubes in >parallel for a video amp with a response from DC to over five MHz. It >was a 'Distributed Amplifier'.   Im not real familiar with transmitters, but I know that tube is used in Ham transmitters and is similar to a 6L6 (or am I thinking 6LQ6?).

jurb6006@gmail.com: Feb 26 09:34AM -0800 > remove. From what I've been seeing lately, google never removes outdated > links. I've been seeing around 35% of the links on google are obsolete > lately.   Actually I can understand why when you search for tube stuff you'll get more broken links. The extinct bound are probably going to get more of that in the future. Hell, I can't even find good food anymore.   Dude, I had to make the transition from tubes to transistors and so can you. On tube TVs I had a superfast method which involved shorting things out. I took a grounded screwdriver to the plate cap ot the horizontal output tube which showed me immediately if there was B+ and if the damper tube was conducting. That ain't the half of it, I cured the Zenith ringing in the video problem.   You can do it too. I just had to learn just how fast transistors can be destroyed. With tubes I oculod short things out and see how long it takes for one of them to redplate and thus eliminate the need for a tube tester. That was radical, but it got results which paid the bills.   Solid state is a bit more tricky.   One of the first things is to figure out which section is faulty. Is it the amp ? If so that might be easy. The tone generators are a different story. In an older organ there will be 12 of them. Find an amp and connect SOMEHOW so you can determine all 12 of those generators work. If not, burn it.   I shit you not. It is too damn hard to find parts foro those things. Even if you do then they run out of tune whenb they heat up n shit. One thing you need for an organ or an older electric piano or anything like that is to have the tone generators working properly. If youu don't have that ytou willl be looking for germanium transistors, some of which have not been made in all my born days. Coils and capacitors it will take you three days to find on Digikey, if you can at all. And of course that depends on you getting the inforation on these parts, Digikey doesn't know, how could they ?   Another bottom line, power circuits blow first. It is entirely possible that your tone generators are fine. You have to test it with another amp. somewhere in there is the output going to the amp, if the thing powers up that is where you start. Connect it to anything. Even an elcheapo pair of PC speakers should do it. Test every key. If they all work we move on to the next step. You be lucky if all them tone gennies work and you just have to fix the amp.

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