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Tim R <timothy42b@aol.com>: Nov 17 04:03PM -0800 I haven't measured. This is what seems logical to me:   When a dehumidifier cools air in the evaporator section and warms the same air up in the condenser section, there should be no net loss or gain to the room. Air comes in, gets cooled, gets heated back the same amount less whatever inefficiencies exist.   However the water in the air condenses. The "heat of condensation" is a lot of energy, given by one source as 590 calories per gram where 1 calorie is the energy to raise one gram of water 1 degree. The water comes off the coil at the coil temperature, while the heat is transferred into the coil. The refrigerant then moves the heat over to the condenser coil, where it is transferred to the air. So, net gain greater than the simple dry air case.   That's what my thought experiment suggests anyway.

amdx <nojunk@knology.net>: Nov 18 09:32AM -0600 On 11/17/2019 6:03 PM, Tim R wrote:   > When a dehumidifier cools air in the evaporator section and warms the same air up in the condenser section, there should be no net loss or gain to the room. Air comes in, gets cooled, gets heated back the same amount less whatever inefficiencies exist.   > However the water in the air condenses. The "heat of condensation" is a lot of energy, given by one source as 590 calories per gram where 1 calorie is the energy to raise one gram of water 1 degree. The water comes off the coil at the coil temperature, while the heat is transferred into the coil. The refrigerant then moves the heat over to the condenser coil, where it is transferred to the air. So, net gain greater than the simple dry air case.   > That's what my thought experiment suggests anyway.   That's my argument also, so at least you and I think that happens. This link has some calculations on heat removed from the condensing of the water and delivered to the room, assuming the condensed water goes out of the room. > https://www.greenbuildingadvisor.com/article/the-pros-and-cons-of-running-a-dehumidifier   And a quote from this page. > https://van.physics.illinois.edu/qa/listing.php?id=31123&t=heat-from-dehumidifier   "*Update: A typical home dehumidifier removes roughly 2L of water per kWh of energy used. That soaks up a bit over 1 kWH of latent heat. So the room warming is about 2kWh per kWh input energy. The efficiency is over 200%, not bad if you want to dry your house air also."   Mikek

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.

Branden <brand555at@verizondot.net>: Nov 17 08:08PM -0500 On 11/17/19 7:27 PM, Branden wrote: > 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.   Here's an image:   https://i.imgur.com/72YjfM9.jpg

Branden <brand555at@verizondot.net>: Nov 17 09:16PM -0500 On 11/17/19 7:27 PM, Branden wrote: > 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.   Ok, I found it. Luminglas or plasma plate or plasma disk. Wow, they are really costly now. The ones in Spencer's 20 years ago were around $40 for 15 inch size... now it looks like at least 3 times that!

Cursitor Doom <curd@notformail.com>: Nov 18 01:45PM On Sun, 17 Nov 2019 21:16:17 -0500, Branden wrote:   > Ok, I found it. Luminglas or plasma plate or plasma disk. Wow, they > are really costly now. The ones in Spencer's 20 years ago were around > $40 for 15 inch size... now it looks like at least 3 times that!   Inflation innit. A price tripling over 20 years doesn't seem that unlikely.         -- 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.

jlarkin@highlandsniptechnology.com: Nov 18 07:27AM -0800 On Sun, 17 Nov 2019 19:27:27 -0500, Branden >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.   An ordinary clear-glass incendescent bulb makes some nice sparks inside if you apply HF-HV to one side of the filament.       --   John Larkin Highland Technology, Inc   lunatic fringe electronics

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.

John-Del <ohger1s@gmail.com>: Nov 17 10:10AM -0800 On Sunday, November 17, 2019 at 12:34:45 PM UTC-5, Cursitor Doom wrote: > > 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.   Japan mostly, but that is supposition on my part. I believe some of those fakes were simply relabeled parts and not necessarily purposely built as counterfeits. Back in the CRT TV days, we'd buy horizontal/line output transistors a hundred at a shot (like the Toshiba 2SC1172B or Sanyo 1308K). Then we started getting counterfeits that would last minutes to days, then blow. We used to buy Sony SG613s in bulk and never had a problem. Suddenly the next shipment would blow up on plug in.   We also saw TONS of Motorola and Toshiba audio outputs for stereo equipment that were relabeled. Vertical ICs, SMPS regulators etc.. There was virtually no category untouched. I even remember the counterfeit Sony "jungle" ICs that would work for a few days, weeks, or months, then cause shutdowns or other odd symptoms. The Sony jungle ICs were complicated devices and these were either line rejects or purposely built to counterfeit. I don't really know nor does it really matter at my end. All I know is that they caused costly callbacks.   My guess is that a lot of the early counterfeits were just the lower power/current/voltage versions of the series that were cleaned and reprinted.

Phil Allison <pallison49@gmail.com>: Nov 17 10:24AM -0800 Cursitor Doom wrote:   --------------------- > > 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.   ** Back in 1980, on open sale in Australia were counterfeit Motorola power transistors. Thousands of them, either included in amplifier kits or across the counter. The devices were branded "TIC" for " Transistor Instrument Company" operating from, Florida. They did not in fact manufacture anything but had a catalogue with hundreds of types.   What TIC did was buy up surplus TO3 stock and remove the original labelling - then re-ink the parts according to your order. So a 10 cent item became worth several dollars each. Just about the only similarity was the TO3 pak. The ones I saw and tried to use were Motorola numbers MJ1003 & MJ15004. The exact same scam was done by fake wholesalers in places like Hong Kong.   Another fake wholesaler in the same state was called "Aero" and dealt mostly in relabelled and used vacuum tubes - again with a large catalogue.   On offer were "new" transmitting tubes from them for hundreds of dollars a piece that had already seen thousands of hours of use. Or tubes from famous US maker Sylvania that were re-labelled stock from places like East Germany or Yugoslavia - for double the going price.   When surplus stocks ran out, shiny new fakes were created in India or China that only resembled the real things in appearance.   Manufacturers well knew to keep away, so sales normally only went to various retail operations and for spare parts.     ..... Phil

John Robertson <spam@flippers.com>: Nov 17 10:33AM -0800 On 2019/11/17 10:10 a.m., John-Del wrote:   > Japan mostly, but that is supposition on my part. I believe some of those fakes were simply relabeled parts and not necessarily purposely built as counterfeits. Back in the CRT TV days, we'd buy horizontal/line output transistors a hundred at a shot (like the Toshiba 2SC1172B or Sanyo 1308K). Then we started getting counterfeits that would last minutes to days, then blow. We used to buy Sony SG613s in bulk and never had a problem. Suddenly the next shipment would blow up on plug in.   > We also saw TONS of Motorola and Toshiba audio outputs for stereo equipment that were relabeled. Vertical ICs, SMPS regulators etc.. There was virtually no category untouched. I even remember the counterfeit Sony "jungle" ICs that would work for a few days, weeks, or months, then cause shutdowns or other odd symptoms. The Sony jungle ICs were complicated devices and these were either line rejects or purposely built to counterfeit. I don't really know nor does it really matter at my end. All I know is that they caused costly callbacks.   > My guess is that a lot of the early counterfeits were just the lower power/current/voltage versions of the series that were cleaned and reprinted.   Japan was a 'problem' back in the 50s and 60s - a friend of mine who lived in Japan in the 60s told me how they literally copied slot machines - they would buy one US slot, take it apart, and build exact replicas...   But, then again, the US was a problem back in the 1700 and 1800s!   Copyright laws did not exist in the US way back when and lots of publications that were protected in Europe were freely reprinted on the other side of the pond..   https://www.varsitytutors.com/earlyamerica/firsts/first-u-s-copyright-law   Currency:   https://www.history.org/Foundation/journal/Summer07/counterfeit.cfm   Roman times:   https://coinweek.com/ancient-coins/bad-money-ancient-counterfeiters-and-their-fake-coins/   Counterfeit stuff has always been around, that is why "bricks & mortar" places like Digikey, Mouser, Element 14, are trusted - unlike parts you buy off eBay or Amazon. Lots of Russian renumbered parts there...   John :-#)#

Cursitor Doom <curd@notformail.com>: Nov 17 06:34PM On Sun, 17 Nov 2019 10:10:00 -0800, John-Del wrote:   > would last minutes to days, then blow. We used to buy Sony SG613s in > bulk and never had a problem. Suddenly the next shipment would blow up > on plug in.     I had no idea it was so universal. I mean, until recently I thought the problem was confined pretty much solely to voltage regulators, but clearly it goes way beyond that. I find it all (the 'infection' of the supply chain) deeply concerning. :(       -- 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.

Phil Allison <pallison49@gmail.com>: Nov 17 10:53AM -0800 Cursitor Doom wrote:   ---------------------- > problem was confined pretty much solely to voltage regulators, but > clearly it goes way beyond that. I find it all (the 'infection' of the > supply chain) deeply concerning. :(   ** The second time ( a few years later) I found myself with fake MJ15003/4 I made an effort to track down the source.   My supplier assured me it was "Motorola Australia" in Sydney - so I rang them and explained the situation. The sales guy checked the company database and found NO sales of those types had been made to the supplier in several years.   Further investigation tracked the importing to a dealer in Melbourne who had offered them to likely customers all over the place. The stock same from a fake warehouse in Hong Kong.   The official line from Motorola here was that one should ONLY deal with authorised suppliers of the brand who offered traceability.   One such dealer told me the problem was rife, claiming hardly a day went by when nobody rang offering to sell them fake semis. The most common back then were memory chips, all nicely packed in bulk containers and all relabelled as to the rated speed.       ..... Phil

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.

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

Fox's Mercantile <jdangus@att.net>: Nov 17 05:08PM -0600 On 11/17/19 9:52 AM, John-Del wrote: > It's a good plan to avoid knock-off parts of any type.   Apparently some people still haven't learned, "Pay shit, get shit."     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Phil Allison <pallison49@gmail.com>: Nov 17 06:01PM -0800 Fox's Mercantile wrote:   ------------------------- > > It's a good plan to avoid knock-off parts of any type.   > Apparently some people still haven't learned, "Pay shit, > get shit."   ** Those who have not learned are dealers in components.   Counterfeiters know their best market and approach firms acting as wholesalers for many brands with "bulk surplus stock" of the same brand at an appealing price. The items then get sold as regular stock the normal rate.   Sometimes, fake items are put into stock by rogue staffers who take away the genuine stuff and sell it off elsewhere. Happened to Farnell a few years back with On Semi power transistors.   Best way to hide a fake semi is to make them look good and sell at standard going prices.     .... Phil

John-Del <ohger1s@gmail.com>: Nov 17 06:29PM -0800 On Sunday, November 17, 2019 at 9:01:31 PM UTC-5, Phil Allison wrote:     > Best way to hide a fake semi is to make them look good and sell at standard going prices.   > .... Phil   They do with with DLP lamps. OEM bulbs over here generally cost $80 U.S. give or take. People started buying ebay and Amazon lamps for a third of the cost of OEM and finding out they were either crapping out immediately or within a few months. They generally are not as bright as well. People started avoiding the cheap lamps.   A few sellers have been selling counterfeit Philips bulbs at prices just below what Philips lamps sell for - seems like a great deal on Philips brand bulbs but it's the same old crappy lamp at a lot more money.

Phil Allison <pallison49@gmail.com>: Nov 18 02:03AM -0800 John-Del wrote:     --------------- Phil Allison wrote:   > They do with with DLP lamps. OEM bulbs over here generally cost $80 U.S. give or take. People started buying ebay and Amazon lamps for a third of the cost of OEM and finding out they were either crapping out immediately or within a few months. They generally are not as bright as well. People started avoiding the cheap lamps.   > A few sellers have been selling counterfeit Philips bulbs at prices just below what Philips lamps sell for - seems like a great deal on Philips brand bulbs but it's the same old crappy lamp at a lot more money.     ** Reminds me of the old trick used by many dealers in second hand furniture.   If they have an largish item that has been taking up space for a while with no sale - they put it out the front with a sign:   " Today's Special "   With double the previous asking price.     ... Phil

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.

Branden <brand555at@verizondot.net>: Nov 17 07:35PM -0500 shorturl.at/cvCQR     Seem like they might be pretty robust for various applications, just wondering if anyone has tried one? There are other venders with them on eBay at even cheaper prices.

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