EEVblog #866 - Mailbag - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: April 05, 2016, 12:54:07 pm
content: Is this a slice of Dave's Brain?Find out in today's MailbagSPOILERS:A silicon wafer bonanza!A temperature sensing plasma etching waferhttp://www.diychristmas.orgBullshit BingoModel car controllerA very expensive single photon counter teardown and some experimentation.Random cheapo Chinese Ebay items! A shocking pen, a wet baby monitor, and the world's worst soldering iron.

author: alexanderbrevig
author_rank: Frequent Contributor
timestamp: April 05, 2016, 01:11:51 pm
content: benched!

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 05, 2016, 01:59:57 pm
content: I was the one who ordered that horrible soldering iron.It cost me £0.99 (AUD$1.86)I think it might be one of the worst items he has every seen,If people want i can order him something even more dangerous.

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: April 05, 2016, 02:04:01 pm
content: 9:45 - new Internet meme TBH.

author: n3vti
author_rank: Contributor
timestamp: April 05, 2016, 02:24:14 pm
content: I loved your reaction to the cheap Chinese products.

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: April 05, 2016, 02:29:29 pm
content: Quote from: n3vti on April 05, 2016, 02:24:14 pmWould love them to be sent to Bigclive.

author: mverber
author_rank: Newbie
timestamp: April 05, 2016, 02:46:30 pm
content: What was the input impedance of your scope set at when you looked at the output pulses from the Photon Counting Module? I think it's designed to provide TTL pulses into a 50 ohm load -- if your scope was set for high impedance, the impedance mismatch might explain the ringing and higher than expected voltages you see on the pulse.

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 05, 2016, 03:22:41 pm
content: This is where i got the crap iron from:http://www.ebay.co.uk/itm/DIY-220V-40W-Electric-Vacuum-Solder-Welding-Soldering-Iron-Tool-Pencil-Tip-/252311675127?

author: ModemHead
author_rank: Frequent Contributor
timestamp: April 05, 2016, 04:04:46 pm
content: Quote from: RGB255_0_0 on April 05, 2016, 02:29:29 pmAre you 100% sure?

author: Mephitus
author_rank: Regular Contributor
timestamp: April 05, 2016, 04:38:00 pm
content: You have no idea how jealous I am over those wafers. I have been wanting some to put in a proper frame for the wall.

author: SeanB
author_rank: Super Contributor
timestamp: April 05, 2016, 04:39:11 pm
content: Just in case anybody is looking for the ebay listing..http://www.ebay.com/usr/abercoPostage to the rest of the world...... Ouch!did order 2 though, and will frame them if they arrive intact.Reason for the detector saturating is internal opamp saturating, as the massive signal exceeds the common mode voltage of the amplifier, either on chip next to the photodiode, or the one outside doing current measuring. A possible solution is to install an optical switch ( though at the cost of the sensitivity going down a lot) to blank the optical path during laser firing. You can use a second detector as well so you get the rest of the data, and this lower sensitivity data from the dead period should still be usable.https://en.wikipedia.org/wiki/Electro-optic_modulatorThe original use depends on the start of the pulse, and is specified for that. Saturation is not a worry on the typical system as they use a very good optical path to reduce leakage light. They want the first return pulse, and not the rest.

author: JAH981
author_rank: Unknown
timestamp: April 05, 2016, 04:40:37 pm
content: Quote from: EEVblog on April 05, 2016, 12:54:07 pmI would love to translate the Bullshit Bingo for you!

author: SeanB
author_rank: Super Contributor
timestamp: April 05, 2016, 05:05:05 pm
content: The SensArray

author: redshift
author_rank: Contributor
timestamp: April 05, 2016, 05:18:23 pm
content: I assume the blue tape is just to hold the dies after they getdicedapart?But does anyone have any more info about the plasma temperature sensing wafer thing?

author: Fungus
author_rank: Super Contributor
timestamp: April 05, 2016, 05:55:43 pm
content: Quote from: redshift on April 05, 2016, 05:18:23 pmYep.

author: flextard
author_rank: Contributor
timestamp: April 05, 2016, 08:03:43 pm
content: I have a similar silicon die documenting project as well and would love to help.

author: Lovely_Santa
author_rank: Contributor
timestamp: April 05, 2016, 08:20:16 pm
content: @ 27:00 when he opens the bag with the soldering iron (or something that is supposed to be a soldering iron at least...)He's getting a "Why-do-I-even-open-this-bags-moment" : ooohhhhh, ohhhhhhh noo

author: Kjetil
author_rank: Regular Contributor
timestamp: April 05, 2016, 08:36:54 pm
content: Quote from: JAH981 on April 05, 2016, 04:40:37 pmThe point of it (as the postcard mentioned) is that it doesn't need much translating. It just shows how international management bullshit is

author: station240
author_rank: Unknown
timestamp: April 05, 2016, 09:02:51 pm
content: Quote from: RGB255_0_0 on April 05, 2016, 02:29:29 pmBig clive already has that iron, he seems to be an expert at finding this crap himself.

author: ChunkyPastaSauce
author_rank: Unknown
timestamp: April 05, 2016, 10:42:15 pm
content: Quote from: Lovely_Santa on April 05, 2016, 08:20:16 pmYeah that was awesome - the nauseation/depression/loathing feelings were real, no rehearsal from what I could see. lol

author: Smokey
author_rank: Super Contributor
timestamp: April 06, 2016, 06:27:34 am
content: Quote from: SeanB on April 05, 2016, 04:39:11 pmBought some wafers. Should make a great addition to my nerd art along with my old revision production solder paste stencils and frames.

author: FloFo
author_rank: Contributor
timestamp: April 06, 2016, 08:21:01 am
content: Regarding the strange signal form on the Single Photon Counters: try using a 50 Ohm terminator at the Scope, should give a much better signal and removing most of the ringing and negative signal resulting in almost square 4.5V pulses with aprox. 35 ns length (at least that is what i measured with the Perkin Elmer SPCM-AQR-14).

author: deephaven
author_rank: Frequent Contributor
timestamp: April 06, 2016, 10:56:17 am
content: Re the Geocoin. I see that 41 Geocachers have "discovered" it on it's page at geocaching.com So there are at least 41 closet Geocachers frequenting this forum. Maybe there should be a special section for Geocachers as it can be fun making caches with electronics in them, so it's not completely off-topic.

author: romelec
author_rank: Contributor
timestamp: April 06, 2016, 12:39:04 pm
content: Quote from: MatthewMorgan on April 05, 2016, 01:59:57 pmSomething like this boiler ?

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 06, 2016, 01:50:17 pm
content: Or this?http://www.ebay.co.uk/itm/Car-Vehicle-Converter-Inverter-Adapter-DC-12V-24V-to-AC-220V-Charger-Power-USB-/361391736543

author: Mephitus
author_rank: Regular Contributor
timestamp: April 06, 2016, 02:19:47 pm
content: Quote from: MatthewMorgan on April 05, 2016, 01:59:57 pmCheck out bigclive.com orhttps://www.youtube.com/user/bigclivedotcomHe regularly does videos on some extremely sketchy chinese ebay tat. Like a 5 port USB charger that had it's grounding sheath tied into the 220v mains. Or a "water heater" that just uses open contact plates straight from the mains to heat the water.

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 06, 2016, 02:21:26 pm
content: Quote from: Mephitus on April 06, 2016, 02:19:47 pmDave's reactions are comedy tho?

author: Hypernova
author_rank: Unknown
timestamp: April 06, 2016, 03:36:13 pm
content: Quote from: SeanB on April 05, 2016, 04:39:11 pmBought the 20pcs pack, what good is disposable income if you don't use it, I spend more on the IEEE subscription I hardly use anyway.

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 06, 2016, 03:43:27 pm
content: Quote from: Mephitus on April 06, 2016, 02:19:47 pmAnd i also am already subscribed to bigclive,Anyway emailed him and he already has this item.

author: jesuscf
author_rank: Frequent Contributor
timestamp: April 06, 2016, 09:17:14 pm
content: If you want to play bullshit bingo visithttp://www.bullshitbingo.net/cards/bullshit/to get your card.

author: strangersound
author_rank: Regular Contributor
timestamp: April 07, 2016, 06:46:24 pm
content: Quote from: MatthewMorgan on April 05, 2016, 01:59:57 pmPlease do, that shit is hilarious!

author: kcozens
author_rank: Contributor
timestamp: April 07, 2016, 07:14:35 pm
content: Quote from: EEVblog on April 05, 2016, 12:54:07 pmAt 41:32 you show a geocaching item. I've never been geocaching but I know someone who has done it in the past. I wanted to find out a bit more about geocaching so I joined the main(?) geocachine website. I found that the tracking item in your video has been logged by several people as having been last seen on your workbench.I have also discovered there are about 50 geocaches within about 3.2km (2 miles) of my home. I didn't realize how popular this hobby is in my area. I have plenty of caches for me to track down if I want to get involved. At least it would give me something to do on my other than going over the same old routes I tend to travel during my walks.

author: Halcyon
author_rank: Unknown
timestamp: April 09, 2016, 01:52:17 pm
content: Dave, what's the go with mobile reception in your lab? I noticed in this video you were on WiFi and your mobile reception was very low? I know the Sony Z3C isn't a crap phone (in terms of reception quality), so what gives? Either you aren't with Telstra or there is some very serious concrete going on and no pico-cells in your building?

author: solarstandard
author_rank: Newbie
timestamp: April 10, 2016, 06:49:53 pm
content: Amazing mailag episode! Thanks, Dave! I really liked the wafer production steps and the Single Photon Counter. I wish there would be someone like Dave doing optoelectronics (lasers, photon detectors, electro- and acoustooptics etc.)... I find these things very interesting (and happend to be doing a PhD in). Maybe there is, anyone have any recommendations?Or maybe Dave could do it? <: He seems very modest in saying he's not an expert, but he's doing it very well!Here's a few ideas on regarding the Photon Counter and the signal in the first 2 us:1) The signal is some sort of real optical backscattering, 2 us is only 300 m roundtrip for light, maybe there's something reflecting it back. Although the abrupt end of the saturaton makes this explanation unlikely.2) Trigger-to-laser emission jitter? You say there's a 600 ns delay between the trigger rising edge and the laser emission and you show a long persistence trace. Is it the same pulse-to-pulse? Maybe 600 ns is just the minimum delay and it varies in the range of 2 us. I'm assuming your laser is Q-switched and these can have pretty much random trigger-to-emission delay. I believe it gets worse with increasing pulse energy.3) EMI from the laser Q-switch ring-down? (Again assuming your laser is Q-switched). I've had major interference problems with a table-top mJ-level Nd:YAG Q-switched system and my detection electronics. After the laser emission the detectors would pick up us transients which would get worse the closer they were to the laser head and the Q-swtich PSU. Even some meters away I would get unacceptble EMI. And it's all with shielded BNC cables, grounded cases etc. It did get better with double-shielded cables though and erm... some tin foil wrapping here and there. Maybe it's the Q-switch EMI pickup that is triggering your detector?4) Finally, if the detector has a gate input, why not use a fast PIN diode with a TTL pulse shaper and use the laser pulse itslef to gate out the initial detector response? (You may need to get creative to have the gate pulse arrive before the laser pulse). If the problem persists, you'll know it has nothing to do with the laser pulse and most likely is purely electronic.And yes, the output for these detectors should be loaded with 50 Ohms. <:

author: tszaboo
author_rank: Super Contributor
timestamp: April 15, 2016, 02:15:00 pm
content: I have half a dozen of these Foxanon (E14 6-ish W) running at home and they are not that bad. They use IC for current regulation, no blinking, the color temperature is sweet and they run more than a year no issues. Definitely not a Philips, but not Wung Hang Lo.

author: Smokey
author_rank: Super Contributor
timestamp: April 16, 2016, 01:41:46 am
content: Got my wafers today. They look bad ass! What do you guys think would be the best way to keep them centered in a picture frame so I can hang them on the wall?

author: ccs46
author_rank: Regular Contributor
timestamp: April 16, 2016, 02:53:34 am
content: Quote from: MatthewMorgan on April 05, 2016, 01:59:57 pmWas that 0.99p delivered??Quote from: MatthewMorgan on April 05, 2016, 01:59:57 pmPlease Do.

author: Mephitus
author_rank: Regular Contributor
timestamp: April 20, 2016, 09:18:15 pm
content: Quote from: Smokey on April 16, 2016, 01:41:46 amIf I was completely bat-shit insane, I might just use some LOCA glue and put it between 2 panes of good optical glass in a suspended frame. But you would need to be careful as hell about bubbles. (LOCA = liquid optically clear adhesive)

author: Smokey
author_rank: Super Contributor
timestamp: April 21, 2016, 01:01:13 am
content: Quote from: Smokey on April 16, 2016, 01:41:46 amI ended up using some double stick tape in a circle around the outside of the wafer on the white mat that came with the frames and sticking the wafers to the mat. Then the mat pushes them against the glass when you put the back on so I don't think they are going anywhere. I'm super happy with how it turned out.

author: Carl_Smith
author_rank: Frequent Contributor
timestamp: April 21, 2016, 03:55:49 am
content: Quote from: kcozens on April 07, 2016, 07:14:35 pmI was into Geocaching for a while but totally quit about 12 years ago. I just recovered my account on the site about a week ago, and found there are around 700 caches within 10 miles of where I live. But it turns out that a vast majority are "micro caches" that are just a tiny vial with a paper inside to sign, stuck with a magnet to a sign post or street light post.I don't really get the point of those. Years ago I did the geocaching to find interesting places to see. I found more parks, hiking trails, interesting things like old bridges over creeks on old country roads in the middle of nowhere, than I had any clue existed in my area. It was more about the journey and the interesting destination than actually finding the cache. Walking 300 feet down the street and finding a paper in a vial on a sign post is not an interesting journey or an interesting destination. Just another check mark on the geocaching site. Guess I need to figure out how to do a search for "real" geocaches.On another note, I've been thinking about how to repurpose an Amazon Dash button to be a "I was here" button for a Geocache. I would need to be near an available WiFi AP though. Maybe I should check if that's been done already...

author: Nerull
author_rank: Frequent Contributor
timestamp: April 21, 2016, 05:24:45 am
content: bigclive also got one of those irons, at least the wires on Dave's were attached:

author: MatthewMorgan
author_rank: Regular Contributor
timestamp: April 21, 2016, 04:59:26 pm
content: Quote from: ccs46 on April 16, 2016, 02:53:34 amYes it was £0.99 delivered.

author: EvilGeniusSkis
author_rank: Regular Contributor
timestamp: April 25, 2016, 06:43:59 am
content: Why does the tencor wafer have a daughter board on it? Why not just build the brains into the wafer?And "wet baby alert"? I thought that was a standard app in all Neuro-electronics projects.