Holm Tiffe wrote:
Adrian Stoness wrote:
[..]
I have an Fluke Trendar 200 IC Testclip where you can place a known good
chip on to a test socket and place the probe with this chip over the pins
of a chip under test. The probe than reports differences in the behavior
from the tested chip and the test normal with LEDs.
I don't used this device jet, since most of the boards I have to repair
have some protective laquer all over the board so this probe would have
problems to get properly contacted.
http://www.ebay.ch/itm/Fluke-Trendar-200-IC-Test-Clip-200-01-Case-/27078176…
Otherwise it would be ideal to find such bugs.
For my problem Chips, that are mostly russian 7400s and 7408s but tohers
too. Its seems that those chips in plativ mold have problems if they where
stored for laon time in moisture environment and get repaowered after
years. They are functioning at first but several days later they fail.
Maybe baking the entire board in an oven before repaowering the chips would
help?
Kind Regards,
Holm
--
Technik Service u. Handel Tiffe,
www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
Attention: Don't buy the tester from the link above. There are some special
IC sockets missing (looking like wire wrap ic sockets) that need to be
configured for the IC type under test. The tester distinguishes between
inputs and outputs with long and short leads. The manufacturer forbids the
use of standard sockets for this purpose since the connectors will be
get damadged this way. Try to find a unit with spare sockets.
Regards,
Holm
--
Technik Service u. Handel Tiffe,
www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741