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Carole <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1000@example.com>: Dec 09 03:37AM , 6 wires ,green ,red,, blue, black yellow white, The blue and the black change direction can you send a diagram to change this motor to high voltage? send : E-Mail: carolplotz@frontier.com   --

Paul Drahn <pdrahn@webformixair.com>: Dec 08 07:39PM -0800 On 12/8/2014 7:37 PM, Carole wrote: > , 6 wires ,green ,red,, blue, black yellow white, The blue and the black > change direction can you send a diagram to change this motor to high > voltage? send : E-Mail: carolplotz@frontier.com   What is an Ajax motor?   Paul

"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 09 08:12AM -0800 > What is an Ajax motor?   It's a specialized motor used in sewage systems. It's part of a mechanism that "floats the dirt right down the drain".   https://www.google.com/search?q=ajax+motor+wiring+diagram&rlz=1T4NDKB_enUS510US510&tbm=isch&tbo=u&source=univ&sa=X&ei=zB6HVPO6AoS6ogSyoYKIAw&ved=0CB8QsAQ&biw=1604&bih=1112   https://en.wikipedia.org/wiki/Ajax_Engines

jurb6006@gmail.com: Dec 08 05:09PM -0800 The horn is DC coupled ? Why the hell would they do that ? Sometimes I wonder what kind of drugs these enginers are on.   I was on audiokarma the other day and someone mentioned a protect circuit that wa powered by the DC from the amp. Not hard to figure out how it works, it is a matter of finding a relay, normally closed of course, that will activate at a low enough voltage and current. Couple resistors going to a bridge and a filter should do it.   I commented about finding a suitable relay, someone replied that it has been done and I might be abe to find the link if anyone wants it.   Another thing was about the magnets on the sides of the relay, remember that thread ? you said that it was to draw the arc away from betweent the point so they would be less likely to weld themselves together due to the inductive CEMF.   I posted that a cap, like a 10 uF or whatever, across the cntacts should work just fine. The guy on AK said it might still pass some sound and I replied in the who cares ? you only care about that DC. If the amp is still putting out sound with a shitload of DC on the output, well isn't that just dandy. So what ?   My Phase Linear 400 Series 2 has no relay, no nothing. My buddy's Adcom GFA545-2 is the same. Both of these amps have plenty of current to smoke things. an Ampzilla is the same way. Depends on a fuse. Shit really.   At any rate, with the right relay there could be a decent addon protector for this.   I also happen to like SCR crowbar protection. I like the SOUND of "crowbar protection" actually, and how it works. I designed a bridged car amp a loing time ago used that. Of course must short out the drive to the outputs when it is active, which it did. If any fusibles blow, then something is shorted for sure.   I said at the time "This baby is more than idiot proof, you hook up the speaker outputs to the car battery it will burn the wires off.   I like cool shit like that. The UL or CSA or whatever might not, but I do.

Phil Allison <pallison49@gmail.com>: Dec 08 08:18PM -0800 > The horn is DC coupled ? Why the hell would they do that ?   ** Most are like that and a real lot have LM3886 amps driving the horn direct.     > I was on audiokarma the other day and someone mentioned a protect circuit that wa powered by the DC from the amp. Not hard to figure out how it works, it is a matter of finding a relay, normally closed of course, that will activate at a low enough voltage and current. Couple resistors going to a bridge and a filter should do it.   ** The relay MUST short the speaker to protect it and that means the contacts are normally open. Since the coil is not polarity sensitive, there is no need for bridge - just some RC filtering and a fuse on the amp side.     > Another thing was about the magnets on the sides of the relay, remember that thread ? you said that it was to draw the arc away from betweent the point so they would be less likely to weld themselves together due to the inductive CEMF.   ** Nope, it is to help break the arc that forms when contact open under heavy DC current and voltage. 40V and 5 amps are the limit for most small AC rated relays - adding a suitable magnet might increase that to 50V and 10 amps.     > I posted that a cap, like a 10 uF or whatever, across the cntacts should work just fine.   ** No it wont.   ... Phil

Phil Allison <pallison49@gmail.com>: Dec 08 09:24PM -0800 Phil Allison wrote:     > In the example on my bench, it looks like an intermittent solder joint in the feed to the -15V supply did the job. The amps test just fine.   > One 10uF bi-polar cap would have saved the horn diaphragm and a simple triac crow bar would have saved the woofer. A couple of dollars worth of components.   ** I have now added a 20uF, 250VAC cap to the horn feed and an active relay board to the woofer amp. The NC contacts short the speaker while unpowered and open about 2 seconds after AC power is applied, the NO contacts then close and the amp is connected. If more than +/- 9VDC is detected the relay drops back to it's rest condition. There is a 7Amp fuse in series with the relay contacts in case of an arc developing to ground from the 80V rail.     ... Phil

jurb6006@gmail.com: Dec 08 10:27PM -0800 Not what I would've done but sounds good.   Now how do you write tyhe bill ?   Really, when you modify something there is no price schedule. I now I only charged rtwenty bucks to wrap a flyback for an HK short in the CRT, but that was after a couple of basic charges that brought it up to a livable level.   Time and materials ? Alot of machne shop shit is judged that way. Not all, they have a couple different ways of doing it.   Here's a freaky one. How to figure out what to charge for a modification :   In the GTE Sylvania E 4X series chassis of color TVs there was a chip witht he part number of 15-43301. this was custom or made by them and only for themselves. I supported a countdown circuit for line sync and frequency.   Well a bunch of them even brand new werr coming out with no sync. You got the picture but it was floating out there, and nothing really fixed it. Well I hade a look at three of the pins and with the resistor, cap and whatever thee, determined that I could probably just put a transistor there to detect the sync. It worked.   Then I figured that this is what Sylvania had done,to simply put that transistor inside the package with the IC. I know people who lost a shitload of monet for not being able to get good ICs like this, if I had done this a few years earlier I could have made bucks and kept the landfills a bit cleaner.

Phil Allison <pallison49@gmail.com>: Dec 09 12:35AM -0800 > Not what I would've done but sounds good.   > Now how do you write tyhe bill ?   > Really, when you modify something there is no price schedule.     ** Yep - always tricky to put a price on designing a custom modification that fixes a nasty problem the maker could not be bothered fixing. I simply had to fit the mods cos the dumb fault that fed full rail DC to the speaker voice coils just might return.   The owner has now seen the work and was happy and he has another 11 of them in constant use.   In this case, my bill is well less than the combined bills for re-coning the woofer and a new horn diaphragm - which I estimate will exceed A$400.       ... Phil

John-Del <ohger1s@aol.com>: Dec 09 04:48AM -0800 > The horn is DC coupled ? Why the hell would they do that ?   > I like cool shit like that. The UL or CSA or whatever might not, but I do.     Price I guess. I don't work on all that many music amplifiers, but I don't recall ever seeing one with speaker protection relays installed. In the case of home audio, they do provide protection because outboard speakers can be pricy (much more expensive than the amp), and folks wouldn't be thrilled to see their amp take out their speakers. In the case of a music amp, they're self contained so I guess manufacturers figure they can sell new drivers if they blow.   As for mods, I've done my share over the years. Technically, we're not supposed to make any modifications unless the manufacturer provides a procedure in a bulletin. From what I heard years ago, the manufacturer is supposed to submit the mod to U.L. (in the States) for approval before it's allowed, but I don't know if that's a fact.

jurb6006@gmail.com: Dec 08 04:49PM -0800 Well I got that fow frequenct oscillator running. The last guy in it changed the rate pot and used a different type. The original made a ground conection to some of the circuitry. However I still have no chorus.   There are no clock pulses coming out of the MN3101. The voltages seem alright, so I figure it is either the IC or the 22 pF cap in the oscillator circuit. I'll just change them both so as not to have too much time in there.   Thing I found out though is that my time is limited when the PC board is not mounted. The outputs are not getting enough heat sink and it will get HOT. If I wind up working on alot of amps built like that I might have to figure something out. Maybe a fan or something. I got standard threaded hole on the transistors', mmounting plate o maybe I can just screw a spare heat sink to that.   If necessary. Might not be because there really isn't that much there to troubleshoot. One of my main problems was my PDF reader not autoscrolling to the next page. I have to select the next page up at the top. Don't say to update my reader, it is new enough and aggravating enough. What I really want is version 4 but it won't read shit anymore. One PC at work has a really newer version in which I can't even find the hand tool. Using the scrollbars is worth shit on a schematic. then they have this propensity for downloading updates for Chinese or Mandarin or Korean fonts. Sorry, maybe I am just a dumb yankee but I do not read Chinese. Or Sanskrit or Farsi or anyting but English. If I had it to do over again I would have taken as many languages as possible when I was young.   Enough rant. The chip and cap will be ordered tomorrow and that is that. I got this thing in a basket but that isn't how it is going out.   Oh Matt, about faking the thing out, I think it needs the two clock phases. I don't have a generator tht can do that so I would have to go through some crap to accomplish it.   Now that I think of it, maybe I should build something just to invert a signal for such circumstances. Simple OP AMP should do it. there may be other things I could use it for, like that breadboard down in my basement. I might actually build something again...

jurb6006@gmail.com: Dec 08 04:54PM -0800 >"When I varied the depth control I heard the sound change"   That was obviously NOT due to the BBD working. the way it is connected though to the BBD bias coming out of that other OP AMP seems like it could allow some effect, but not the desired one.   If the BBD was being clocked and the only problem was the low frequenct oscillator not running I think the effect of the depth control would be much more pronounced.   So really, that indicates that the guy who changed the pot either made an error or broke the thing somehow. Of course that's the kind of shit I get all the time. I get a nice unit with all the original screws and parts, with the original problem only, I just don't know what to do with myself.

mroberds@att.net: Dec 09 03:10AM > There are no clock pulses coming out of the MN3101. The voltages seem > alright, so I figure it is either the IC or the 22 pF cap in the > oscillator circuit.   Apparently the diode and 5.1 K resistor are part of the MN3101 oscillator as well. In general it looks like they are using U16/U17/U11 to apply some additional signals to the MN3101 oscillator. (If I remember right, in the one I built, the MN3101 just oscillated on its own... there was an RC network on pins 5/6/7, but that wasn't connected to anything else.)   > Thing I found out though is that my time is limited when the PC board > is not mounted. The outputs are not getting enough heat sink and it > will get HOT.   How about a few of those heat sinks that use a spring clip - either flat metal or a wire bail - to hold the heat sink to the transistor? Not for running the thing outside of the case at 200 W for hours on end, but just for running at low power for 10 or 15 minutes while troubleshooting.   > Don't say to update my reader, it is new enough and aggravating > enough.   If you don't like Adobe Reader (or Acrobat Reader or whatever Adobe is calling it this week), I have had reasonable luck with Foxit Reader. Seems to be less bloated than the Adobe offerings.   > The chip and cap will be ordered tomorrow and that is that.   I think the MN3101s are surplus/Ebay only now, but there still seem to be some around. It's CMOS, so take your shoes off.   > Oh Matt, about faking the thing out, I think it needs the two clock > phases.   I don't remember the details, but I'm pretty sure that it does need both phases.   A quick Google shows that some people have been kicking around the idea of using some 4000-series CMOS chips instead of the MN3101. Some of them are worried that it'll sound different: http://www.diystompboxes.com/smfforum/index.php?topic=72447.0   Matt Roberds

jurb6006@gmail.com: Dec 08 04:56PM -0800 What makes it junk ? I just barely started to take it apart and I think that I might just not need an answer to that question.   I had a nice tight bit in those allen screws and the wanted to strip. Don't they harden metal in Italy ?

"David Farber" <farberbear.unspam@aol.com>: Dec 08 10:02AM -0800 David K. Bryant wrote: > error message often means that the paper failed > to reach a sensor at the right time.   > --- news://freenews.netfront.net/ - complaints: news@netfront.net ---   Is the clutch serviceable or is not worth the effort?   Thanks for your reply. -- David Farber Los Osos, CA

Michael Black <et472@ncf.ca>: Dec 08 12:11PM -0500

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