Search found 2250 matches
- Feb 07 2019 7:11pm
- Forum: Forum Rules and Features
- Topic: The future of our forum - facebook versus web forums
- Replies: 44
- Views: 2540
Re: The future of our forum - facebook versus web forums
First, wondering what Justin's thoughts are? Second, not a supporter of FB. More and more of it's security flaws are going to be exposed, and I think it is near the top of its curve right now. Third, a conservative, planned migration to the next generation message board engine may be a consideration...
- Feb 01 2019 9:18pm
- Forum: General Discussion
- Topic: This man may change the world Andrea Rossi & eCat
- Replies: 358
- Views: 26356
Re: This man may change the world Andrea Rossi & eCat
... I can't figure out what his endgame is. His approach doesn't really make sense if the goal is to monetize a scam invention. Unless he really does think it works; he may be able to delude himself sufficiently to keep that belief alive. Very possible a small group of ol' guys with a little dement...
- Feb 01 2019 3:59pm
- Forum: Items for Sale - Used
- Topic: F.W. Bell Model 9640 Hall Effect Gaussmeter with STB4-0404 probe TESTED
- Replies: 1
- Views: 193
Re: F.W. Bell Model 9640 Hall Effect Gaussmeter with STB4-0404 probe TESTED
An update on this one too. You can't find a better magnetometer, but It appears it was too pricey. Now willing to sell at a loss at $899 plus UPS shipping. It is still up on the auction site we all know and love. Meter and probe are calibrated and ready to rock and roll.
- Feb 01 2019 3:56pm
- Forum: Items for Sale - Used
- Topic: SOLD--ACDC Electronic Model EL-750 Electronic LOAD BANK TESTED
- Replies: 1
- Views: 232
Re: ACDC Electronic Model EL-750 Electronic LOAD BANK TESTED
I'm going to throw up an update on these. I have sold two of them for $279 and only have one left. If anyone in the USA is interested, will sell for $279 plus UPS shipping costs. If you want to make an offer do so. These are rock solid 750 watt all day electronic loads.
- Feb 01 2019 3:49pm
- Forum: General Discussion
- Topic: This man may change the world Andrea Rossi & eCat
- Replies: 358
- Views: 26356
Re: This man may change the world Andrea Rossi & eCat
Amazing as it may seem, Rossi is still at it and still getting money from investors. Yep I watched it all and couldn't believe it. The echo from a perhaps empty garage, and perhaps three people on chairs and a bare concrete floor (because of the echo). He kept talking about the "dancing ballerina" ...
- Jan 28 2019 9:19am
- Forum: General Discussion
- Topic: Magnify Glass vs Jewelry Microscope Magnifier Loupe
- Replies: 14
- Views: 430
Re: Magnify Glass vs Jewelry Microscope Magnifier Loupe
I have three headbands with the flip down lenses in 1.5 2.5 and 3.5 power. For surface mount PCB work a stereo microscope with Barlow lens. ... and LOTS of light. It seems I am adding lighting above my bench with every 5 years of age.
- Jan 23 2019 8:02am
- Forum: E-Bike Technical
- Topic: I broke a bolt in my hub motor. How do I get it out?
- Replies: 14
- Views: 419
Re: I broke a bolt in my hub motor. How do I get it out?
Here is what I do for broken screws/bolts on really expensive things. It takes a mill (Bridgeport) however, but you may be able to adapt. Lock the part down on the table with fixturing. Take an end cutting end mill and make the top of the broken screw perfectly flat Use a center drill and your skill...
- Jan 20 2019 7:24pm
- Forum: E-Bike Technical
- Topic: How Many Amps 2 Pole Speakon Socket handle?
- Replies: 9
- Views: 227
Re: How Many Amps 2 Pole Speakon Socket handle?
Thank you for all the info, going with all the info I am going to ask ddk on his thread to get more accurate info, as I have doubts the 2 pole can handle 30A :shock: ... Note the specified 3mOhm contact resistance. At 30 amps that 2.7 watt dissipation per contact, or 5.4 watts per 2 pole connector....
- Dec 12 2018 8:35pm
- Forum: Large EV General Discussion
- Topic: What’s stopping Ford and GM from building compelling EV’s?
- Replies: 19
- Views: 766
Re: What’s stopping Ford and GM from building compelling EV’s?
Always an pleasure and honor to see you Bigmoose. Most of the decision maker position folks at these companies are ICE/Hybrid legacy mindset folks who viewed EVs as the burdensome and financially costly compliance requirement to sell their gas cars into California. If you have two boats, you might ...
- Dec 12 2018 10:31am
- Forum: Large EV General Discussion
- Topic: What’s stopping Ford and GM from building compelling EV’s?
- Replies: 19
- Views: 766
Re: What’s stopping Ford and GM from building compelling EV’s?
Its not about vision but about Return On Investment. The european market and mindset is very different than the USA. Its all about the distances and population density. I'm a rural guy in the USA. Always have been, and Lord willing, always will be. I live where there is 3 months of that white stuff ...
- Dec 12 2018 10:22am
- Forum: Motor Technology
- Topic: Sensorless at standstill, development updates and status
- Replies: 78
- Views: 4517
Re: Sensorless at standstill, development updates and status
Lebowski great tech! You deserve the :wizzard: label for sure! I would recommend you form a company. Make your technology the company's IP. Then approach the big guns of TI. This is a chip level solution with associated algorithms. If TI bites, they will buy out your company for the IP. Typical tech...
- Nov 02 2018 10:46am
- Forum: Motor Technology
- Topic: High side vs Low side PWM
- Replies: 74
- Views: 4651
Re: High side vs Low side PWM
Can you share the part number of the polymer caps that you are using?
- Nov 02 2018 10:09am
- Forum: Electric Aircraft
- Topic: Farfles Electric Ultralight.
- Replies: 196
- Views: 20258
Re: Farfles Electric Ultralight.
Great thread, great build, great flights! 

- Oct 04 2018 6:57am
- Forum: Motor Technology
- Topic: How much Heat can To-247 handle in real world
- Replies: 10
- Views: 484
Re: How much Heat can To-247 handle in real world
Electron, I'm an ol' guy now...and have forgotten the specifics of this calculation I did back in 2012. There should be a thread on here with a deeper discussion. Note the significance of switching losses versus conduction losses at high PWM frequencies.
- Sep 02 2018 3:40pm
- Forum: General Discussion
- Topic: TEST 850w table heater and 685w desk heater ( 2nd bill in, page 6)
- Replies: 137
- Views: 10262
Re: Got new $243 AC for my central air system! (quick test)
A little off the thread tangent, but relevant. I built the house in 1987, and I personally installed a 5 ton R22 system. I bought a 30lb bottle of R22 just to have it back then... cost about 100 bucks. Fast forward to last year. Old system was costing me a total of 500 bucks a month to run during ju...
- Aug 31 2018 8:59am
- Forum: General Discussion
- Topic: Best way to remove all components off a PCB
- Replies: 5
- Views: 335
Re: Best way to remove all components off a PCB
I've salvaged components a few ways. The delicate way is to use a solder sucker often called a desoldering station. I use a METCAL-SP440-Desolder-System-with-Handpiece-SP-PW3-11 I would use this to get temperature sensitive components off the board. Then I have a dedicated toaster oven. I put the bo...
- Aug 11 2018 6:32pm
- Forum: Items for Sale - Used
- Topic: F.W. Bell Model 9640 Hall Effect Gaussmeter with STB4-0404 probe TESTED
- Replies: 1
- Views: 193
F.W. Bell Model 9640 Hall Effect Gaussmeter with STB4-0404 probe TESTED
Gents, I have for sale a great F.W. Bell Model 9640 Gaussmeter complete with STB4-0404 probe. This is a very thin probe that can get between a rotor and stator. I is up on that auction site that we all know and love... haha... but would give preferential treatment to ES members. Unit has been cleane...
- Aug 11 2018 6:23pm
- Forum: Items for Sale - Used
- Topic: SOLD--ACDC Electronic Model EL-750 Electronic LOAD BANK TESTED
- Replies: 1
- Views: 232
SOLD--ACDC Electronic Model EL-750 Electronic LOAD BANK TESTED
Last one of these SOLD on 2/2/2019 Gents, I have 3 of these ACDC Electronic Model EL-750 Electronic LOAD Bank that are perfect for Lithium Battery cyclic life testing or power supply testing. I have them up on that auction site that we all know and love... haha... but would give preferential treatm...
- Jun 28 2018 7:33am
- Forum: Battery Technology
- Topic: Lightweight lithium battery for car
- Replies: 16
- Views: 873
Re: Lightweight lithium battery for car
I think you should take a look at the classic A123 LiFePO4 pouch cells. IIRC they are spec'ed to around 300 amp peak discharge.
reference http://www.a123systems.com/automotive/products/cells/
reference http://www.a123systems.com/automotive/products/cells/
- Nov 25 2017 8:46am
- Forum: E-Bike General Discussion
- Topic: ☠ Heat Damage to Motors (Magnets) ☠
- Replies: 21
- Views: 1368
Re: ☠ Heat Damage to Motors (Magnets) ☠
This was a very important parameter for us in the aerospace industry. We often baked the magnets at various temperatures for various times and developed a matrix of their specific demagnetization characteristics so that we could keep our systems performance up to par for decades in space. Outside of...
- Nov 25 2017 8:34am
- Forum: General Discussion
- Topic: Differences between the old and new version of phpbb & proposed changes
- Replies: 137
- Views: 24612
Re: Differences between the old and new version of phpbb & proposed changes
nep, thanks for stepping up to this huuuuuge job! As you said, without the move to modern servers, operating systems, and bbs software we were a sitting duck... one hacker away from loosing everything.
Thanks again!
Thanks again!
- Sep 16 2017 12:07pm
- Forum: General Discussion
- Topic: TEST 850w table heater and 685w desk heater ( 2nd bill in, page 6)
- Replies: 137
- Views: 10262
Re: $680 zoned HVAC instead of $5000 central system
Some thoughts as this has been my summer of A/C repair/replacement and large industrial dehumidifier repair. First, there are some decent R22 replacements that don't have flammable components. R407c is a decent substitute in R22 A/C systems. It needs POE oil however. If you can replace all the miner...
- Sep 13 2017 4:08pm
- Forum: General Discussion
- Topic: anyone Ever Fixed an alternator?
- Replies: 28
- Views: 2603
Re: anyone Ever Fixed an alternator?
Oreilly auto parts has one in stock the ultima rebuild for $191 does this look like yours? They will ship to you. OK i looked closer once I posted this. The manual transmission one is out of stock. The automatic transmission is in stock. The difference looks like it is just the Pulley. So take your ...
- Sep 13 2017 12:08pm
- Forum: Battery Technology
- Topic: Calculating System Reliability
- Replies: 6
- Views: 679
Re: Calculating System Reliability
Ahhhh this is so easy...not! Just define all mechanical failure modes as noncredible in the FMECA because of pull test on crimped connectors. Then do the rest according to MIL-HDBK-217 ... easy peasy... yea right. Methy, about 8 years ago now, I was contemplating getting into battery systems for mob...
- Sep 12 2017 4:53pm
- Forum: General Discussion
- Topic: anyone Ever Fixed an alternator?
- Replies: 28
- Views: 2603
Re: anyone Ever Fixed an alternator?
If it's got 140,000 to 160,000 it's likely the brushes are just worn. I've rebuilt a ton over the years... only had one with a blown diode, and then it was in one leg of the 3 phase only, so the alternator still had minimal output, and that was back in 1976. Then again, if you can't get an alternato...