Search found 5 matches

by vinnieb
Wed Mar 06, 2019 1:19 pm
Forum: DSO138
Topic: Triggering at 50ms per division and below
Replies: 33
Views: 51552

Re: Triggering at 50ms per division and below

Could anyone repost or share somehow that latest 66 firmware? Don't know if its just me or the files have been rehosted/moved, but any that I download from here I get corrupted checksum errors when I try to open the rar file, be it on windows or linux. From the sounds of it, the 66 is worth going fo...
by vinnieb
Wed Nov 01, 2017 9:19 pm
Forum: DSO138
Topic: Strange test signal, shape and behaviour
Replies: 8
Views: 9630

Re: Strange test signal, shape and behaviour

Got it!! So, first I have to admit I was accidentally focussing on the SEN1 switch rather than the SEN2 which is what I now understand you meant. It was the SEN1 movement from 0.1V either side that didn't seem to have the expected effect on the test signal measurement, so maybe why I thought that wa...
by vinnieb
Tue Oct 31, 2017 8:24 pm
Forum: DSO138
Topic: Strange test signal, shape and behaviour
Replies: 8
Views: 9630

Re: Strange test signal, shape and behaviour

Ah interesting! I match those values for measuring ground to R7 ends. U2 pin 10, as you look down on the board, 3rd up from the right hand side? Was best I could tell from chip diagrams, couldn't see an obvious end marker on the surface mount version here. If that is the one, I get a consistent 120 ...
by vinnieb
Mon Oct 30, 2017 6:32 pm
Forum: DSO138
Topic: Strange test signal, shape and behaviour
Replies: 8
Views: 9630

Re: Strange test signal, shape and behaviour

Thanks for the suggestion! By open you mean, if I check the resistance of it while its on the board, it would be zero? I've checked those 3 and they're all matching the schematic values, and I tried cross checking to see if I got the incremental values measuring across them, and that value came out ...
by vinnieb
Sun Oct 29, 2017 7:18 am
Forum: DSO138
Topic: Strange test signal, shape and behaviour
Replies: 8
Views: 9630

Strange test signal, shape and behaviour

Hi, Put together my DSO138 a few weeks ago and really love the kit! Initially had some problem with the -5V supply due to soldering skills, but that seems pretty stable now. But, you can see in the attached images I get some strange test signal behaviour. On DC, 0.5V the wave is far from square, and...