EEVblog #1165 - Cypres Parachute Safety AAD Teardown - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: January 03, 2019, 02:01:25 am
content: DejaVu. Dave revisits the new generation Cypres 2 parachute Automatic Activation Device and tears it down.A safety device that automatically activates your parachute at a pre-set altitude. It has saved over 4000 lives to date.

author: station240
author_rank: Unknown
timestamp: January 03, 2019, 02:48:08 am
content: Dave, the little board with the two SOT23's on it, also has some sort of 3 pin thru hole part.Could pry it out to see what that is.Also having found the lithium cell was dead, why did you not apply a bench supply to see if it powers up ?

author: cnxunuo
author_rank: Regular Contributor
timestamp: January 03, 2019, 03:28:41 am
content: The plastic is the cartridge wall, which holds the wedge shaped slug in place, heres an 300Kv xray of before and after

author: cnxunuo
author_rank: Regular Contributor
timestamp: January 03, 2019, 03:33:24 am
content: from left to right,electric wire with some lead based primer charge wrap as a ball, hense the high density.copper cased primary charge, ruptured in the topwedge slug with shock absorbing.I have tried some salvaged from E-waste, it cuts thru steel wire like butter. There's a bigger handheld version which uses real 9mm cartridge without projectile, can do 16mm steel bar in one shot (handheld)

author: max_torque
author_rank: Super Contributor
timestamp: January 03, 2019, 09:30:54 am
content: When ever i see "life rated" i'm always amazed at what a bodge the devices actually look! Loads of iffy soldered flying leads, bodge components etc.......

author: Chipguy
author_rank: Unknown
timestamp: January 03, 2019, 10:09:30 am
content: This transparent gel can be bought in 2x 1 kg glass bottles, it's a two component stuff that is pretty expensive. It has a shelf life of only 6 months.After that the gel becomes unstable and does not fully "dry" and will still flow around.Somebody wants some?It's no problem to use it with the pressure sensor, it transfers the pressure in a very very linear way.In fact it is so linear that Fluke uses that in their type 713 pressure calibrators. They use a NovaSensor NPC1210 with that gel inside to make it moisture resistant.I have made some experiments with that gel for pressure sensors as well, and used Merit M12 series sensors.They are also available with that gel inside the chimney, but with black dye.Reason is that pressure sensors are also light sensitive and the gel then blocks the light.It does not matter in the Cypres Product since there is no light inside.

author: Kleinstein
author_rank: Super Contributor
timestamp: January 03, 2019, 10:17:30 am
content: It looks like the pressure sensor went out with the gel. At least the chip is gone at the end.I was expecting some labels outside to show it being not RoHs. As least aviation electronics can still require (not just allow) leaded solder.

author: johnlsenchak
author_rank: Frequent Contributor
timestamp: January 03, 2019, 10:39:03 pm
content: Why would somebody be a "Melf" resistor / diode fanboy, that's just strange in my opinionAnyway, Dave how come you didn't connect the bench power supply to the device directly in place of the battery to see if it powered on?That might have made the video a little more interesting , just say'in

author: LapTop006
author_rank: Unknown
timestamp: January 04, 2019, 11:22:41 am
content: Quote from: johnlsenchak on January 03, 2019, 10:39:03 pmI've heard claims that they're still better at specific things (stability or RF? can't remember).Either way Stanford Research's (SRS) design department do seem to be members of that club.

author: Chipguy
author_rank: Unknown
timestamp: January 04, 2019, 11:58:57 am
content: Quote from: LapTop006 on January 04, 2019, 11:22:41 amAt one time that really was the case. They used to have less aging and especially a lower tempco than chip resistors.They also were better in terms of high current pulses.But since around 2003 this has changed and precision / rugged resistors are more available in chip casings.

author: mcovington
author_rank: Regular Contributor
timestamp: September 20, 2019, 01:56:48 am
content: Everybody who makes CPAP machines needs to see this video. Notoriously, CPAP machines get water in their pressure sensors whenever anybody tilts the machine the wrong way and empties the water canister into the air tubing. Beyond economic repair ($$). Why can't they just use that gel?