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John Robertson <spam@flippers.com>: Apr 20 08:39AM -0700 On 2020/04/20 12:04 a.m., Mike Mocha wrote: > incorporated a "tip" I made regarding vacuum tube televisions on his TV > FAQ back in 1997! I had a lot of great memories lurking and posting in > this group from 1995 to 1997. Thanks all!   Welcome back! Were you trapped on a desert island with only a volleyball for company?   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."

jjhudak4@gmail.com: Apr 19 01:43PM -0700 Following up on my repair effort, I'll document what I found in case anyone going down this road stumbles on this writeup.   In short the unit uses a Peltier module heat pump to both heat and cool the yogurt container. The Peltier module was bad in my unit - gave a constant ~30K ohms reading, connected it to a 12vdc battery source, no heat what so ever. The module is a TEC1-12705. To my surprise none of the usual electron parts houses have them (Mouser, Digikey, avnet, allied, newark, etc.) Amazon has them ranging in price from $6 to $10 from varying sources and from what I see in the reviews, all parts are of questionable quality. To my surprise, they are available through Walmart! Not sure where to get the OEM part - suggestions? pointers appreciated.   Description of the unit, it contains: 1) 5 VDC 6A smps, which feeds a... 2) a 2"x3" micro based control module that contains connections for: the Peltier module, a rtd/thermister temp sensor, power supply input. 3) the heat/cool stack composed of 1.25" aluminum heat block encased in styrofoam, the peltier module, a massive Al finned heatsink (5"x 2.5") and a 3" fan bolted to the finned heatsink.   Getting the unit apart is a little tricky because it has 4 plastic fingers that lock the bottom half of the unit to the top half - need to simultaneously unlock all four tabs then separate the top and bottom.   Couldn't see any obvious design or implementation screwups, although I question why there is a 1.25" thick piece of aluminum between the Peltier module and the bottom of the yogurt container. I'll need to do some heat transfer calcs to see if they are controlling the module correctly and take some temp measurements to infer their desired (required) heating and cooling temps.   From what I could tell on the scope the output to the Peltier module was fairly smooth DC voltage that is (my guess) a LPF PWM output to a power transistor (MOSFET?) from the microcontroller The markings on the chip were unreadable due to some clear coat that was put on the chip. A lot of speculation here since I could not read a lot of the component markings. My googlefu failed to turn up anything about the components, although the PS looks like it is an off the shelf module from somewhere.     Next step is to get the replacement Peltier module, perhaps upgrade the thermal silicon grease, and reassemble. J

John-Del <ohger1s@gmail.com>: Apr 20 04:46AM -0700 > The module is a TEC1-12705. > To my surprise none of the usual electron parts houses have them (Mouser, Digikey, avnet, allied, newark, etc.) Amazon has them ranging in price from $6 to $10 from varying sources and from what I see in the reviews, all parts are of questionable quality. To my surprise, they are available through Walmart! > Not sure where to get the OEM part - suggestions? pointers appreciated.   Walmart is a poor man's Amazon. Many of the things sold on Walmart's online site are deliverd from someone's basement, and I don't know if Walmart would offer the same protections as Amazon, as good or as bad as that might be.

Allodoxaphobia <trepidation@example.net>: Apr 20 12:55PM On Mon, 20 Apr 2020 04:46:45 -0700 (PDT), John-Del wrote: >> To my surprise none of the usual electron parts houses have them (Mouser, Digikey, avnet, allied, newark, etc.) Amazon has them ranging in price from $6 to $10 from varying sources and from what I see in the reviews, all parts are of questionable quality. To my surprise, they are available through Walmart! >> Not sure where to get the OEM part - suggestions? pointers appreciated.   > Walmart is a poor man's Amazon. Many of the things sold on Walmart's online site are deliverd from someone's basement, and I don't know if Walmart would offer the same protections as Amazon, as good or as bad as that might be.   Walmart == Made In China Store   Even those who lower their expectations are often disappointed.

Bob Engelhardt <BobEngelhardt@comcast.net>: Apr 19 08:29AM -0400 On 4/19/2020 2:29 AM, Mike S wrote: > What about installing an on/off switch to isolate the battery from the > pcb when not in use?   That's a good idea - thanks. Wouldn't be the 1st time that I've done a bodge like that 8-) I'll look into it.

Mike Mocha <mocha@mailexcite.com>: Apr 20 07:04AM Wow! I just got back on Usenet after literally 18+ years and it's great to see this is one of the last text groups still active with real people talking! Good to see Sam Goldwasser and others still on here. Sam incorporated a "tip" I made regarding vacuum tube televisions on his TV FAQ back in 1997! I had a lot of great memories lurking and posting in this group from 1995 to 1997. Thanks all!

Jeff Liebermann <jeffl@cruzio.com>: Apr 19 10:18AM -0700 >is large enough. Sometimes I temporarily glue it in place to get proper >alignment while drilling. It has saved me a lot of time waiting for >parts. I also have a drill and tap for a 1-72 screw if that is needed.   I do something similar when desperate. Instead of drill and pin, I use a flexible sewing pin (not a needle) and my soldering iron. I put some gouges in the surface of the pin, heat the pen head, shove the pin into the parts that I want to glue, and wait for the plastic to harden. When done, I cut off the head of the pin with flush cutting diagonal cutters or a Dremel tool with a cutoff disk. If I need pull strength, I use a straightened paper clip instead of a pin. The paper clip metal is softer, so I can use my wire cutters to roughen the surface of the paper clip. I heat instead of glue to assemble the parts because the hole is usually in some inaccessible location that can be reached with a soldering iron, but not a Dremel drill tool.   Another alternative is plastic welding. <https://www.harborfreight.com/plastic-welding-kit-with-air-motor-and-temperature-adjustment-96712.html> <https://www.harborfreight.com/plastic-welding-kit-with-adjustable-temperature-96464.html> I modified a spare tip for my SMD hot air desoldering tool by adding a smaller nozzle suitable for plastic welding. So far, it's worked nicely for parts about the diameter of a pencil. However, my attempts at plastic welding small parts usually result in a blob of plastic or a cloud of plastic smog. The next time I get a laptop in the shop to fix, with the usual ultra-thin standoffs broken off by the threaded brass inserts, I'll give plastic welding another try.   >As you are aware, it breaks where at the point where it needs the >most reinforcement.   Yep. However, my usual problem is finding the broken off plastic piece.     -- 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

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 19 10:08AM -0700 On Saturday, April 18, 2020 at 4:49:52 PM UTC-4, kill...@coronavirus.com wrote:   Forwarded to: fbi.gov/coronavirus Forwarded to: abuse@web.com (Via whois)   May you die exceedingly slowly, and hurt the entire time you are dying.

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