used electronics

Pantherjon

Well-Known Member
Joined
Jan 19, 2009
Messages
7,434
Reaction score
6
Or some will occasionally sell theirs in the 'Yard Sale' section of the forum here.
 

FredA

Well-Known Member
Joined
Jan 18, 2009
Messages
2,849
Reaction score
1,023
I've got a collection -- only one crash each.... :rolleyes:

Seriously -- I recommend you avoid buying used.
You don't know the condition of the electronics.

Static damage is a sleeper that is nearly impossibile to detect.
Sensors are easily damaged on a hard landing and this damage is rarely caught by on-board diagnostics that alert the user to a potential issue.

We (Team Hardtail) had one rocket that stripped the chute and came in hard.
Everything looked ok....the electronics passed it's POST....
But failed on the next launch because he accelerometer didn't detect the launch.........

If our altimeters had some "real' diagnostics, the story would be different.
For now, buyer beware.
IMHO,
FredA
 

ben_ullman

Well-Known Member
Joined
Jan 17, 2009
Messages
1,523
Reaction score
2
ive got some used altimeters you can can have. If I can just find the other 1/2 of that MAWD, and theres one in the ground in Maryland if you can find it.

Ben
 

rocketsmith

Well-Known Member
Joined
Oct 12, 2009
Messages
440
Reaction score
1
I've got a collection -- only one crash each.... :rolleyes:

Seriously -- I recommend you avoid buying used.
You don't know the condition of the electronics.

Static damage is a sleeper that is nearly impossibile to detect.
Sensors are easily damaged on a hard landing and this damage is rarely caught by on-board diagnostics that alert the user to a potential issue.

We (Team Hardtail) had one rocket that stripped the chute and came in hard.
Everything looked ok....the electronics passed it's POST....
But failed on the next launch because he accelerometer didn't detect the launch.........

If our altimeters had some "real' diagnostics, the story would be different.
For now, buyer beware.
IMHO,
FredA

I've got a missleworks rrc2 that came in semi-hard under a drouge and a partial main last month on soft wet sod. It seems okay and since it uses a baro sensor I should be fine, right? Maybe I should fly it with an old reliable I don't care about first?
 

FredA

Well-Known Member
Joined
Jan 18, 2009
Messages
2,849
Reaction score
1,023
The accelerometers and pressure sensors used today are MEMS devices.
These have small moving parts that can be damaged by extreme shocks.

Testing after a questionable landing is always recommended.

In my case -- the broken accelerometer was easily found once we went into the calibration mode -- but the altimeter itself in normal flight mode was "too stupid" to notice that gravity was reading only 0.1G during POST.
 

Pantherjon

Well-Known Member
Joined
Jan 19, 2009
Messages
7,434
Reaction score
6
I've got a missleworks rrc2 that came in semi-hard under a drouge and a partial main last month on soft wet sod. It seems okay and since it uses a baro sensor I should be fine, right? Maybe I should fly it with an old reliable I don't care about first?

If it were me? I would use it, and not think twice about it..Why? Well, my Perfectflite(I know, different make but still...) was riding in my ill fated first L1 attempt when the rocket lawn darted from about 1800 feet..It works perfectly! I imagine a 'semi hard' impact/landing with your RRC2 didn't phase it at all- after all it is subject to up 50g(or more) loads when the event charges go off..

Here are the remains of the rocket that my Perfectflite crashed in- operator error on setting up the altimeter sled, not enough space between baro sensor and the sled..DOH!:blush:
0209launch002.jpg
 
Top