help identefing TO92 device . please harry up  - Page 1
Forum section: electronics / projects

author: eevblogfan
author_rank: Frequent Contributor
timestamp: May 09, 2013, 11:09:37 am
content: Hey .i am in the job and we have fluke thermometer in here . the castumer said that ther's somerhing pilled off and i should now replace it ... i came to order the part but didn't found the device on findchips ... so please help me ?The device is national semy's ...( they'r logo ) ... and thers written :"752 (next line ) sx ( next line )23281Thank you in advance !

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: May 09, 2013, 11:30:24 am
content: Hi,It sounds like a Fluke part number. What is the model number of the thermometer?Have you found the manual?Jay_Diddy_B

author: eevblogfan
author_rank: Frequent Contributor
timestamp: May 09, 2013, 11:52:50 am
content: Fluke 51/jmenual of the part - nope

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: May 09, 2013, 12:03:45 pm
content: Hi,The manual is available here:http://www.to-way.com/teqman/Fluke/51_52/5152____smeng0100.pdfIt includes the schematicsJay_Diddy_B

author: eevblogfan
author_rank: Frequent Contributor
timestamp: May 09, 2013, 03:21:37 pm
content: heyhow can I find the To 92 device's name in there ?sorry for me being that fool

author: ddavidebor
author_rank: Super Contributor
timestamp: May 09, 2013, 05:08:57 pm
content: Watch the board layout and check on the component table

author: eevblogfan
author_rank: Frequent Contributor
timestamp: May 09, 2013, 06:43:34 pm
content: heyIt's Q1 , on the menual it says " temperature sensor transistor " but ther's no part number]does someone know how shall I find that ?thank you in advance !

author: free_electron
author_rank: Super Contributor
timestamp: May 09, 2013, 07:54:30 pm
content: thhaaaatssss theeee coooooolddd juuuunccctiiooooonnn seeeeenssoooooorrr.. aaaa cccaaaareeefuuulllllyyyy seeleeeecteeed traaaansisssssstooooor tooooo meeeeeeaaaaasuuuuuurrrreeee theeee teeempeeeeeraaaatuuuurrreeeeee aaaatt ttheeeee cooooonnneeeecctoooor toooo cooompeeeensaaaateeee foooorr theeeeee seeeebeeeeck effeeeeect iiiiin theeeee cooonnnneeeeccctoooooor.thiiiiis issss aaaaa paaaaart seeeeeleeeected iiiin faaaactooorryyyyy...naaaaatioooonaaal stoooopppeeeed toooo maaaakeee traaaaanssiiiisssstooooorrrrsss loooongg agooooo.aaaanyyyyyweeeee , iiiiitsss aaa fluuuuukee onnnnnlyyy paaaart....juuuuusssssttt beeeecaaaaauuuussssseee yooooouuuuu aaaaaskeeedd tooooo haaaaaarrrryyy uuup ...

author: eevblogfan
author_rank: Frequent Contributor
timestamp: May 09, 2013, 08:12:28 pm
content: heyfree . have you smoked some marijuana ?LOL , ummm , shall I contact fluke ?PS , I know what's the purpose of that device is , I've seen dave's vids about the subjectthank you

author: mikes
author_rank: Regular Contributor
timestamp: May 09, 2013, 08:31:20 pm
content: I'd try a common 2N3904. You would, of course, need to calibrate and then check it across the range.Read the Linear app notehere. It discusses using the 2N3906 (PNP), but you need an NPN.More info.Edit: Fluke used 2N3904 (actually, MMBT3904, Fairchild) in the 80TK thermocouple module. Q1 in the 51/52 is probably just a factory selected (or maybe parameter tested) 2N3904.