EEVBlog #851 - Mailbag - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: February 15, 2016, 10:19:36 pm
content: Several Teardowns on today's MailbagSPOILERSSony M-50 Discman The world's first portable CD player.A weird Japanese pinball game machine display with huge VFD display.The Joey, a, I2C Raspberry Pi LED display boardhttp://www.gooligum.com.au/joey-dispA D-Link router that has released the magic smoke.The Hack-A-Day Omnibus:http://store.hackaday.com/products/hackaday-omnibus-2015Fluke Networks EtherScope teardownTektronix have a new logo

author: Jorpy
author_rank: Contributor
timestamp: February 15, 2016, 10:50:14 pm
content: I think the VFD is multicolor, using different phosphors

author: nitro2k01
author_rank: Frequent Contributor
timestamp: February 16, 2016, 12:23:08 am
content: "Si+PB"This caught my attention. Could Dave or anyone else who has access to the book look up what that article is about? If it was about lead, I would assume that they would write it correctly as Pb.The point of the moss thing is perhaps to grow moss only where the light isn't masked. It's possible that the moss thing has already gotten x-ray treatment to sterilize it. Although then it would probably have a note and an invoice from customs attached.

author: DrGeoff
author_rank: Frequent Contributor
timestamp: February 16, 2016, 12:33:23 am
content: Pachinko is the Japanese equivalent of the pokies here in Aus.It's a gaming machine with loads of ballbearings that fall through it.Pachinko parlours are full of these machines and, as you can imagine, are very noisy.Check them out next time you are in Tokyo. They are quite interesting.

author: coadaman
author_rank: Newbie
timestamp: February 16, 2016, 03:48:40 am
content: Hi DaveThis is first time i'm using your forum, i tweeted few times at you but it doesn't matter, you are a great guy, i'm not an engineer or anything similar but i have interest in technology in general and i do love your videos (although i don't understand everything i grasp at some basic concepts)I have only one plea for you and i hope you will do that for us "young players"WHAT IS WRITTEN IN CODE ON T-SHIRTGratitude Master

author: bktemp
author_rank: Super Contributor
timestamp: February 16, 2016, 06:37:27 am
content: Quote from: Jorpy on February 15, 2016, 10:50:14 pmYes. Yellow segements typically light up red or orange.And Dave missed something else:There is most likely a driver ic embedded inside the display!If you count the rows, it is impossible to drive the display using the few available pins.Below the graphics area there are some a fat traces. This is probably the common anode voltage voltage.Dave, please try to open the display and show us some nice closeups using the microscope.

author: Kadah
author_rank: Newbie
timestamp: February 16, 2016, 07:07:33 am
content: I had a similar model of the D-link router. It did the exact same thing with the included power adapter the first time it was plugged in. Oops.Would have returned it or at least complained, but it was one of the myriad of free junk that Best Buy gave away during the Windows XP launch.

author: Stonent
author_rank: Super Contributor
timestamp: February 16, 2016, 08:16:24 am
content: I'll just cut and paste here what I wrote about the Etherscope on Youtube.We still use an Etherscope like that, but I think ours is an Etherscope II but looks very similar except it has a compact flash port for data storage as well as pcmcia. It runs Linux and can do cable testing and you can put in a wifi card as well. It can do impedance testing of twisted pair wiring, wire map, some signal loss, time domain reflectometry for cable length and distance to damaged or shorted cable. When you're running tests the relays are clicking off and on, probably connecting the wires to the FPGA for testing before switching back to that broadcom chip . You can also do network capture for offline analysis.It can measure voltage on each wire of the differential pairs also so I suppose the FPGA may have some analog capability for that. You can also use it as a tone generator for tracing wires with a fluke wire probe.It's a bit slow to boot up with its old PXA chip so it isn't used as much today. We have a Fluke Linkrunner that gets used for most cable testing and troubleshooting and a big modular Fluke tester that can be converted into several models by changing out the backpack module.Here's a video on the Etherscope II.

author: nwvlab
author_rank: Regular Contributor
timestamp: February 16, 2016, 08:37:25 am
content: Hi Dave!could you please check the color of the LEDs of the board with the VFD? Because I don't really think that the yellowish soldermask has been caused by the UV coming from the LEDs (you should see at least some sort of shadows around the LEDs). Even blue LEDs emit a very very very negligible amount of UV (it's almost on the noise floor of our spectrometers). Longer wavelenghts LEDs (green, yellow, red) emit really 0 UV (well... maybe some photons per second).Only some very recent white or other phosphor converted LEDs could emit some traces of UV, as some of them are using an UV LED (instead of blue one) with an optimized phosphor. But that piece of hardware seems to me quite old to contain such a new technology.I think that, as you originally said in your video, UV came from the outside solar light (which, even though there is a quite thick plastic, some UV could still penetrate and reach the soldermask! Much more than any UV emitted from LEDs). And maybe that gaming machine was outside some pub or bar, and some reflected light could still reach that gaming machine.Cheers!

author: DrGeoff
author_rank: Frequent Contributor
timestamp: February 16, 2016, 11:36:39 am
content: Quote from: nwvlab on February 16, 2016, 08:37:25 amThe UV would have come from common indoor fluorescent tubes. I have seen this before, and other plastic items go brittle and crumble away after a few years under fluoro lighting.

author: Don Hills
author_rank: Regular Contributor
timestamp: February 16, 2016, 12:13:18 pm
content: Regarding the D-50 Discman: Keep an eye out for the accessories.There was a cradle containing a mains PSU which the player slotted onto, with RCA sockets for the line out.There was a large carry case with internal shock mounts that completely enclosed the player.Last time I had mine out (a few years ago) it still worked.Single DAC chip multiplexed between the channels, NOS (Non OverSampling).

author: Fungus
author_rank: Super Contributor
timestamp: February 16, 2016, 12:43:37 pm
content: Re: the display...What was THAT doing in Leeds?

author: max666
author_rank: Frequent Contributor
timestamp: February 16, 2016, 01:31:27 pm
content: Quote from: bktemp on February 16, 2016, 06:37:27 amI was thinking the same thing.

author: AF6LJ
author_rank: Unknown
timestamp: February 16, 2016, 02:00:45 pm
content: This should be good...Regretfully I am going to be too busy to watch this today or tomorrow...It may have to wait till Friday.I love VFD displays as much as I love Nixie displays.Mailbag always gets watched here even with the annoying re-focus on close ups....

author: kalleboo
author_rank: Regular Contributor
timestamp: February 16, 2016, 02:52:46 pm
content: The first thing I thought when I saw the PCB miscoloring was nicotine stains... (Pachinko parlors are notorious for being noisy smoky hellholes)

author: max_torque
author_rank: Super Contributor
timestamp: February 16, 2016, 03:30:55 pm
content: Good mail bag!Particularly the off-the-cuff "Tektronix scopes are slow as a wet week" dig and the "Thatched Cottage" mix up. For overseas readers, this is a Thatched Cottage:

author: philh
author_rank: Newbie
timestamp: February 16, 2016, 05:10:08 pm
content: You can check the colors of the VFD by shining a black light onto it.Be very careful if you break open the display the Red Phosphor is very Toxic.

author: Supercharged
author_rank: Regular Contributor
timestamp: February 16, 2016, 06:06:09 pm
content: My go at the textronix code:it's 2 lines (top and bottom half): both are lines which can be converted to binarry 00100100 and 11001010. if you invert the second half it will give you ASCII numbers which convert to $5 so maybe something will cost 5 bucks.Note: its just a guess from 1 minute of guessing

author: zapta
author_rank: Super Contributor
timestamp: February 16, 2016, 06:10:09 pm
content: [quote author=Supercharged link=topic=63121.msg870927#msg8if you invert the second half it will give you ASCII numbers which convert to $5 so maybe something will cost 5 bucks.Note: its just a guess from 1 minute of guessingMakes sense, it's a hint for the future company valuation.

author: MatthewEveritt
author_rank: Unknown
timestamp: February 16, 2016, 06:41:01 pm
content: What was with the daughter board in the pachinko machine display? It looks like they had to add extra TVS diodes in parallel with the existing ones?As for the pattern on the tee shirt, maybe it's just a meaningless distraction. New new logo on the way?

author: f4eru
author_rank: Super Contributor
timestamp: February 16, 2016, 06:41:36 pm
content: The coloration on the PCB and the transparent window of the pachinko thing is probably from cigarette smoke !!If you go to Japan, I recommend going (for a few seconds) into a pachinko house. Incredible noise !!You will spot them easily by walking past the door : if the door opens, a loud continuous metallic white noise comes from the inside

author: Neilm
author_rank: Super Contributor
timestamp: February 16, 2016, 09:01:54 pm
content: My guess on that moss thing - it is moss. You can see it. So perhaps it is CMOS

author: grantbob
author_rank: Unknown
timestamp: February 16, 2016, 11:53:14 pm
content: Quote from: f4eru on February 16, 2016, 06:41:36 pmIt's supposed to sound like this:http://www.allmusic.com/album/pachinko-in-your-head-non-linear-music-mw0000601093(I have the CD... it comes in a metal tin... which seems appropriate)-grantbob

author: Grecord
author_rank: Newbie
timestamp: February 17, 2016, 11:26:06 pm
content: Yellowing looks like bar smoke to me. I've seen many examples of exposed pcbs in service over years from the security industry and you oftne get those "Drifts" of grunge on the surface especially when there are heated(relative) components.

author: generic_username
author_rank: Regular Contributor
timestamp: February 19, 2016, 10:49:53 am
content: This mailbag had some nice items, really liked that japanese PCB.OFT where to get that autorouter T-shirt? Didn't find it in the merch section?

author: retrolefty
author_rank: Super Contributor
timestamp: February 19, 2016, 01:35:00 pm
content: Looking forward to the Sony disc player tear down. I owned one at one time and it was a great unit at the time, very solid even heavy construction. I believe these are even collectible and carry a premium on E-bay.

author: Godzil
author_rank: Frequent Contributor
timestamp: February 24, 2016, 01:11:14 am
content: I'm interested in more information about the Japanese thing, google is not my friend and Sangyo + Win View does not give any thing interesting.Does any of you (or the one who sent it to dave) have more information about that device?By the way, the chip on the Fluke network screen is made by PVI and not OPVI, PVI who is Prime View International, and become later... E-Ink!Cf:http://www.eink.com/press_releases/pvi_eink_reach_agmt_060109.html

author: coppice
author_rank: Super Contributor
timestamp: February 24, 2016, 03:30:57 am
content: Quote from: Grecord on February 17, 2016, 11:26:06 pmIn most developed countries people are starting to forget how so many things, like furnishings, used to be badly discoloured by smokers. Japan still has a great many smokers, and discolouration is still a big issue there.

author: AF6LJ
author_rank: Unknown
timestamp: February 24, 2016, 03:13:47 pm
content: Good Video The condition of the SONY Disc player is amazing.

author: Godzil
author_rank: Frequent Contributor
timestamp: February 24, 2016, 03:57:24 pm
content: By the way it looks more like a shelf CD player than a discman

author: Len
author_rank: Frequent Contributor
timestamp: February 24, 2016, 11:18:32 pm
content: Quote from: Godzil on February 24, 2016, 03:57:24 pmThe D-50 was a portable CD player, however the battery pack was a separate accessory. I don't know if Discman was an official name or just a nickname at that time - later models had "Discman" printed on them.

author: Zom-B
author_rank: Regular Contributor
timestamp: December 11, 2016, 09:59:14 am
content: The Tektronics code is:Up/down: binary (LSB first) '00101010' = ASCII 'T'Thickness: '00000011' = ASCII '?'Spacing: (maybe I'm over-thinking things) '000 111 00' = '8' (not quite 'K' as I hoped)?