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Ralph Mowery <rmowery28146@earthlink.net>: Nov 18 10:08AM -0500 In article <97f7e90a-db15-4238-998a-bac41c84c5db@googlegroups.com>, pallison49@gmail.com says...   > " Today's Special "   > With double the previous asking price.   People are funny about things.   I know a man that sells cantalopes and other items at a farmers market.   He had them for $ .25 each and not selling. He took that sign and marked through it and made it 3 for $ 1. Sold most of them at the higher price. People did not do the simple math and see that they were paying about 8 cents more for each one.

Fox's Mercantile <jdangus@att.net>: Nov 17 05:07PM -0600 On 11/16/19 10:09 AM, Ralph Mowery wrote: > in an old one even if the board may have other problems and not used.   > Now if it was a $ 10 or even maybe a $ 5 part it may be worth putting > the old part back on.   Not even with $5-10 parts. My time is worth more than that.   > sooner than a new one. Then you have to do it all over again.   > It takes often takes more labor time and effort to test than to just > put in a new one.   Exactly, and then you KNOW they aren't the problem.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

etpm@whidbey.com: Nov 15 12:01PM -0800 On Fri, 15 Nov 2019 11:27:05 -0800, John Robertson <spam@flippers.com> wrote:   >with the programmer burn process) and then they tested just fine. I >assume I recharged the gates so all was then well.   >John :-#)# I will need to erase the EPROMs before they get new programs. My wife has a UV light source she uses for curing some sort of fingernail coating for artificial nails. I'm hoping it will work OK. The programmer I am buying is the MCUmall Electronics model GQ-4x4. I called them and they said programmer software verifies the info downloaded from the EPROM and then once again verifies the uploaded info. Eric

Cursitor Doom <curd@notformail.com>: Nov 17 05:34PM On Sun, 17 Nov 2019 07:52:26 -0800, John-Del wrote:   > It's a good plan to avoid knock-off parts of any type. Many of old > timers have seen counterfeit parts going back 40 years or more.   Where did those fakes come from 40 years ago?? I'm guessing certainly not from China. China joined the game *much* later AFAIK.   > have a huge selection of caps. So one can select not only value, > voltage rating, and lead configuration, but also have the option of > selecting manufacturer, ESR, and lifetime hours ratings.   It's kind of baffling when one first sees the range of choice available from those two suppliers, though. I find it takes me *so* much longer to find the part I want than when I was with Farnell/CPC which had a much more limited range. Sometimes you can have too much choice and it becomes a PITA to sort through it all, even with all those filters. Perhaps I'll feel differently once I eventually get used to it.   > I generally only buy Panasonic capacitors because I've grown to trust > them.   Amen to that. Same here!       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

amdx <nojunk@knology.net>: Nov 17 04:42PM -0600 > Greetings John, > Actually the machine starts to work after it has warmed up for a > while.   If this is a consistent response, you may be able to locate the problem by heating/cooling the board. The easiest way is to have the board warmed and working. Buy yourself a can or two of 'Freeze Mist' spray half the board to cool it down, while checking operation. If it still works, let it warm up completely so you don't confuse the issue. Now cool of the other half of the PCB and check operation. If it malfunctions, you know which end to continue troubleshooting. Warm it up until proper operation, then start cooling individual parts on the bad 1/2 of the pcb, one at a time until the problem occurs. You can often isolate the problem part this way.   Or you can do just the opposite, cool the pcb in the fridge, then use isolated heat until the machine works. It is harder to isolate the heat than to cool an individual part. So, I recommend the first procedure. If you decide to use heat on the pcb, use a hair dryer, not a heat gun.   Mikek   Freeze Mist, pick the best price with shipping. > https://www.google.com/search?client=firefox-b-1-d&q=freeze+mist Skip the CRC automotive product, I suspect it has other chemicals in it.

John Robertson <spam@flippers.com>: Nov 15 01:48PM -0800 > machines, while similar, are never the same. I'm even afriad to copy > them. That's why I am going to practice on some others first. > Eric   Reading is pretty safe, however I would recommend you contact MCUmall and make sure that the READ process for pin 21 is done at 5VDC and not at the programming voltage which is 21VDC. You can verify this with a voltmeter by simply not having any chip in the socket and then do a read while monitoring socket pin 21 (ad common at pin 12) to make sure the voltage is 5VDC. It would not hurt to verify that pin 24, again relative to pin 12 - is also 5VDC. Lastly, for the paranoid folks, I would also check pin 20 and 18 to make sure they are never higher than 5VDC.   I am not saying the MCUmall programmer is bad, I'm just pointing out how I would check any programmer that I am trusting irreplaceable EPROMs to!   If you have a scope so much the better to test the programmer READ voltages at the various pins!   As you say you only have the one set of EPROMs and your equipment would be worthless if any are damaged by the programmer!   Does this machine have an 8-bit CPU such as Z80, 68XX, 6502, etc? If someone lives near you and has a Fluke 9010 with the appropriate pod then they could extract the data from the EPROMs at no risk to them. They would also need an RS-232 port on the Fluke to grab the data... I can do this in my shop, but I suspect we are not very close - I'm in Vancouver (Burnaby, but no one knows that city), Canada area...   John   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Cursitor Doom <curd@notformail.com>: Nov 17 12:57AM On Sat, 16 Nov 2019 15:46:48 -0800, John-Del wrote:   > So if I have to replace a board that caps won't fix, why go through the > trouble of recapping it?   I'm worried about cheap Chinese crap getting into the supply chain and that's why I'd rather leave things be. I might end up replacing a perfectly serviceable 40 year old cap made by a prime manufacturer with something nasty from China that's going to go *phut* long before the original one would have.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Cursitor Doom <curd@notformail.com>: Nov 15 09:40AM On Thu, 14 Nov 2019 18:32:29 -0800, John-Del wrote:   > 99% of the time a board that works normally when heated has a lazy > electrolytic.   Or a dry solder joint somewhere on the board.   > If the electro replacement doesn't fix it, try cooling individual parts > to see if you can get it to act up.   Good call. For which you can use stuff like 'pipe freeze' or 'Arctic freeze' with the fine straw inserted - sold at your local plumbing supplies. Clean the board with IPA afterwards.         -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

etpm@whidbey.com: Nov 15 12:47PM -0800 On Fri, 15 Nov 2019 12:38:19 -0800, John Robertson <spam@flippers.com> wrote:   >good 2716s to burn and a few spares...   >Please do not erase your originals!   >John :-#)# I will NOT be erasing the originals. They are, as near as I can tell, not available from any soyrce. I have looked for a long time on eBay in the hope that someone scrapping a machine will have some. But the machines, while similar, are never the same. I'm even afriad to copy them. That's why I am going to practice on some others first. Eric

Chris <cbx@noreply.com>: Nov 14 11:34PM OK, thanks to everyone who responded. I'd thought that volume feature would be unique to one manufacturer to be honest - I've never seen it on any other amp. I think now someone mentioned JVC and that *does* ring a bell. It's just that I'd never equated JVC with the best of the amps of that era. Looks like I may have to review my prejudices. The search goes on...

makolber@yahoo.com: Nov 20 01:59PM -0800 to the OPs question...   concrete and cinder block are porous to moisture.   Paint the walls with Drylock and the floors with a suitable low permeability paint. That will help a lot right off the bat.   In the winter, if your furnace is in the basement, that is usually enough to keep it warm and dry.   In the summer, do not promote outside air exchange when it is humid outside.   I have my electronic gear down there, I try to turn it all on once a week for n hour and I do run a dehumidifier near the gear. If you have AC, make sure the condensate is dumped outside, not into the basement.   Do promote outside air exchange when it is sunny and dry and a nice breezy day, open the window.   Its a process. :-)     m

Ralph Mowery <rmowery28146@earthlink.net>: Nov 16 11:16AM -0500 In article <3172fcc8-cfa4-4313-ae22-b23bc9d8300e@googlegroups.com>, timothy42b@aol.com says...   > A dehumidifier should be heat neutral as you say.   > I?m not so sure about the process. A phase change is involved, when water goes from gas to liquid it has to dump all that phase change energy.   > I use a dehumidifier in the basement. If you figure out how to make one last more than 2 years let me know.   The dehumidifiers in homes do produce some heat from the motors. Not much, but some. Then if you have to empty the water by hand, you are not loosing heat by the water to ammount to anyting.   Many people do not get very many years out of their dehumidifires. Looks like they should as they are nothing much more than a refrigerator with an open door or even an airconditioner.   I have not thought about it , but I wonder if you put a window AC in a room and a drain bucket under it if it would not be just as good as the dehumidifier and last longer.   I think the newer ones do use the splash from the condenced water to help cool the coils.

amdx <nojunk@knology.net>: Nov 16 12:08PM -0600 On 11/16/2019 10:16 AM, Ralph Mowery wrote:   > The dehumidifiers in homes do produce some heat from the motors. Not > much, but some. Then if you have to empty the water by hand, you are > not loosing heat by the water to amount to anything.   I have found several sites that either complain about the extra heat produced by a dehumidifier or explain why they produce heat.   Dehumidifiers are over unity heat producers with a 1.5 COP.   My dehumidifier was recalled as a fire hazard, had to send in the cutoff power cord. I'm tempted to reinstall a cord, run and then measure the temperature of the condensate to see if heat is removed and how much. It may not be much as I have seen that as part of the calculation. I thought it was applicable and still not sure it isn't. Mikek

Cursitor Doom <curd@notformail.com>: Nov 14 11:42PM On Sun, 10 Nov 2019 18:37:41 -0800, Michael Terrell wrote:   > leaving the remaining part of the capacitor, in circuit. If you measure > the capacitance of a damaged X or Y capacitor, it will be lower than > marked.   Yeah, I guess it would. Anyway, after hacking a hole in the bottom of the motherboard I was able to removed the cap in question from underneath and it looks far worse now I can see it properly. It definitely let go in a big way and now I'm pretty confident it was the source of the loud bang I heard. I've also carefully examined all the other sub-boards and the PCB underneath them and they're all fine. Shards of broken cap were scattered about the area of the explosion. Shame I had to butcher the board to get it out, but there was no other way open to me. I follow what you said about removing that j6 power connector but I just don't have the dexterity I'm afraid. So it was a case of Dremmel to the rescue! :-)

Fox's Mercantile <jdangus@att.net>: Nov 14 08:24PM -0600 > 1234   > Server Issues?   UR 5X9 NTX, QSL?       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"Paul Hovnanian P.E." <paul@hovnanian.com>: Nov 18 08:28PM -0800 Part of that price is the size. If you must have a 15" disk, it's going to cost you. 6" are about $25 to $30.   -- Paul Hovnanian mailto:Paul@Hovnanian.com ------------------------------------------------------------------ The large print giveth and the small print taketh away. -- Tom Waits

Branden <brand555at@verizondot.net>: Nov 18 03:33PM -0500 On 11/18/19 3:20 PM, John Larkin wrote: >> great age, like John and I, in order to remember such obsolete atrocities.   > But don't heat the filament, just apply a lot of high voltage, high > frequency stuff to it.   Yes, Ive applied clear incandescents to a HV source too! It can produce a different display from an actual plasma globe depending on bulb vacuum or type of gas used. One has to be very careful of the 25 watt incandescents though if applied to high voltage. Some of those used to produce x-rays because they were vacuumed but not backfilled! I think manufacturers have corrected this nowadays, but 20 years ago they were not backfilled.

John Larkin <jlarkin@highland_atwork_technology.com>: Nov 18 12:20PM -0800 On Mon, 18 Nov 2019 20:17:16 -0000 (UTC), Cursitor Doom   >John means a lightbulb with a tungsten filament in it which burns very >brightly when a current is passed through it. You have to have attained >great age, like John and I, in order to remember such obsolete atrocities.   But don't heat the filament, just apply a lot of high voltage, high frequency stuff to it.   --   John Larkin Highland Technology, Inc picosecond timing precision measurement   jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

Cursitor Doom <curd@notformail.com>: Nov 18 08:17PM On Mon, 18 Nov 2019 11:49:12 -0800, John Larkin wrote:   > No, I meant an ordinary light bulb.   John means a lightbulb with a tungsten filament in it which burns very brightly when a current is passed through it. You have to have attained great age, like John and I, in order to remember such obsolete atrocities.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Nov 18 10:59PM +0100 On 18.11.19 21:20, John Larkin wrote: >> great age, like John and I, in order to remember such obsolete atrocities.   > But don't heat the filament, just apply a lot of high voltage, high > frequency stuff to it.   Like putting one in the microwave. To protect the microwave, also put a glass of water inside. The lamp does not need to be in working order.

Branden <brand555at@verizondot.net>: Nov 18 12:41PM -0500 >> purchase.   > An ordinary clear-glass incendescent bulb makes some nice sparks > inside if you apply HF-HV to one side of the filament.   If you're talking a "plasma globe", yes I have one of those. It is about 14" diameter and cost me $19 at Walmart about 15 years ago. However, I see that even those in many cases appear to be somewhat higher in price, but certainly not nearly as high as the luminglas!

Branden <brand555at@verizondot.net>: Nov 17 07:27PM -0500 What I'm thinking of is not a plasma globe, although, like the globe, it too is intended primary for display. If I were to describe it, I remember it being made out of glass, maybe 1-2 feet in diameter, and nearly flat in thickness. Electric discharges from the center to the edge of the glass and looked a lot like lightning. I remember these devices being used in Star Trek The Next Generation used behind the heads of Borg drones. They used to be in Spencers too available for purchase.

Mike Coon <gravity@mjcoon.plus.com>: Nov 19 09:41AM In article <90a7fa1c-d41f-4118-a383-ed0c053340a7@googlegroups.com>, pallison49@gmail.com says...   > ... with thinly veiled treats ...   Is that like "the dance of the seven veils"? ;-)   Mike.

KDKA2 <kdkaa@pa.com>: Nov 18 08:42PM -0500 Anyone here have difficulty dealing with this firm? I ordered parts from them to build a kit, but the remainder of the parts needed are outdated. I contacted them, but they take forever to respond and said they would refund but that's been well over a month ago. Anyone know how to get them moving?

Bill <Bill@William.COM>: Nov 18 12:36PM -0800 Electronic equipment has a rubber like material on the handle.   It is coming off and I want to glue it back on.   What is best to clean both the plastic handle and the rubber-like material ?   What is best glue to use to put it back on.   Probably needs to be slightly flexible since the rubber-like material is the hand grip.

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