Search found 13 matches

by johng
Sun Jan 20, 2019 10:54 pm
Forum: DSO Shell
Topic: Power supply of DSO150: laptop power supply + DP20V2A
Replies: 1
Views: 2307

Re: Power supply of DSO150: laptop power supply + DP20V2A

1) I watched the video... at approx. 18:50, the fellow suggests adding extra filtering on the output, if you're concerned about the noise. Think low-pass filter. 2) Another option... The DP20VAS in combination with the laptop supply seems like it would make a cheap/useful bench supply. But it seems ...
by johng
Sat Dec 29, 2018 12:29 am
Forum: DSO Shell
Topic: About WallWarts and Bricks...
Replies: 1
Views: 4049

About WallWarts and Bricks...

INTRO There was a recent post about problems with a 9V adapter ("Let the smoke out", Dec24/18) for the DSO Shell. I was going to reply there but thought this might serve better as a generalized post about using plug-in power supplies (as opposed to batteries). TEST First: * always * measu...
by johng
Sat Mar 10, 2018 9:52 pm
Forum: DSO138mini
Topic: DSO 138 Mini error
Replies: 1
Views: 3597

Re: DSO 138 Mini error

>> Getting a bridge between two contacts is a nightmare to to sort out, especially when I ain't got no solder braid yet. When you get the braid... if it doesn't seem to be wicking up the solder very well, try adding a bit of extra flux to it (liquid or paste). Also, a solder sucker (aka desoldering ...
by johng
Thu Aug 17, 2017 6:31 am
Forum: DSO Shell
Topic: Testing SENSEL 0/1/2/3 ?
Replies: 2
Views: 3099

Re: Testing SENSEL 0/1/2/3 ?

I'll take that as a "yes". Thanks.
by johng
Wed Aug 16, 2017 9:40 pm
Forum: DSO Shell
Topic: Testing SENSEL 0/1/2/3 ?
Replies: 2
Views: 3099

Testing SENSEL 0/1/2/3 ?

The Main board has test points for the SENSEL states, but they're only accessible if the Analog board is disconnected. It appears the SENSEL states are independent of the Analog board ( http://www.jyetech.com/forum/viewtopic.php?f=19&t=1108#p3510 ), is this correct? In which case, I can disconne...
by johng
Wed Aug 16, 2017 8:55 pm
Forum: DSO Shell
Topic: Firmware update: help request.
Replies: 12
Views: 11088

Re: Firmware update: help request.

I just upgraded from 54 to 62 firmware yesterday. I also found that connecting tx -> tx and rx -> rx was what worked to make the connection. And, I said OK to the "Remove Protection" query -- maybe that's the difference? Edit: I found this post, which says "Remove Protection" is ...
by johng
Wed Aug 09, 2017 1:56 am
Forum: DSO Shell
Topic: C5 calibration on new version
Replies: 15
Views: 13812

Re: C5 calibration on new version

Jan, I think there's some misunderstanding here. If you are able to modify the wave shape of both the 0.1 and 3.3 test signals by adjusting C3, this strongly suggests that SENSEL3 isn't being toggled properly. If this is the case, then the C5/U1A circuit is *not* used at all. Modifying capacitor val...
by johng
Tue Aug 08, 2017 1:37 pm
Forum: DSO Shell
Topic: C5 calibration on new version
Replies: 15
Views: 13812

Re: C5 calibration on new version

@AlphaSeek - thanks for the pointer. >> So you're adjusting C5, but the input being selected is still the one adjusted by C3. That makes sense, but, If this is the case, then I think adjusting C3 should have some effect on the shape of the 3.3V signal, shouldn't it? (It didn't.) >> Has anyone compar...
by johng
Sat Aug 05, 2017 4:05 pm
Forum: DSO Shell
Topic: C5 calibration on new version
Replies: 15
Views: 13812

Re: C5 calibration on new version

My experience... Firstly: 1) When I compare circuit diagrams (older vs newer boards), this portion of the circuit is exactly the same, with same values. I expect tuning to have similar results for both boards. 2) I have an older board, dated 2016, with #54 firmware. There is a known bug to do with r...
by johng
Thu Aug 03, 2017 2:05 pm
Forum: DSO Shell
Topic: C5 calibration on new version
Replies: 15
Views: 13812

Re: C5 calibration on new version

When you say "new version", do you mean the recent board revisions?
I think this should still apply: the "FAQ, Tips, and Troubleshooting" post, pinned at the top.
There is a subsection "Calibrating C5 and C3"

If yes to the revised board, where did you get it?