<marcos__>
#0 0x00007ffff7b8f002 in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (__str=<error reading variable: Cannot access memory at address 0x68>, this=0x7fffffffd5f0) at /usr/include/c++/7/bits/basic_string.h:440
<marcos__>
#1 0x00007ffff7b8f002 in OscilloscopeChannel::GetHwname[abi:cxx11]() (this=0x0) at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/lib/scopehal/OscilloscopeChannel.cpp:199
<marcos__>
#2 0x0000555555581e52 in OscilloscopeWindow::UpdateStatusBar() (this=this@entry=0x5555558e6210) at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/src/glscopeclient/OscilloscopeWindow.cpp:736
<marcos__>
#3 0x0000555555581ff8 in OscilloscopeWindow::OnWaveformDataReady(Oscilloscope*) (this=this@entry=0x5555558e6210, scope=scope@entry=0x55555582b4d0)
<marcos__>
at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/src/glscopeclient/OscilloscopeWindow.cpp:707
<marcos__>
#4 0x000055555558230b in OscilloscopeWindow::PollScopes() (this=0x5555558e6210) at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/src/glscopeclient/OscilloscopeWindow.cpp:664
<marcos__>
#5 0x00005555555acbf1 in ScopeApp::run() (this=0x5555557cdf30) at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/src/glscopeclient/main.cpp:101
<marcos__>
#6 0x000055555557da51 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at /home/marcos/paltatech/tools/glscopeclient/scopehal-cmake/src/glscopeclient/main.cpp:237
<marcos__>
um, sorry, thats probably not the proper way to paste stuf into irc
marcos__ has quit [Ping timeout: 248 seconds]
marcos__ has joined #scopehal
futarisIRCcloud has quit [Quit: Connection closed for inactivity]
<azonenberg>
ok there we go, that's something i can actually work with
<azonenberg>
marcos__: yeah a pastebin is normally preferred for that many lines
marcos__ has quit [Ping timeout: 272 seconds]
<azonenberg>
Welp, got some initial measurement
<azonenberg>
LED ground pins (whatever they're made of) are no better than the steel needles
<monochro1a>
azonenberg: iirc... more steel
<monochro1a>
or something, they stick to magnets :P
<sorear>
steel + rf sounds like a bad time, skin effect in iron is bad enough at 60hz?
<azonenberg>
let me see if those are magneti
<azonenberg>
you gotta be kidding me
<azonenberg>
they are
<azonenberg>
here i was thinking they were tinned copper
<azonenberg>
so this means my ground impedance has been all out of whack too
<azonenberg>
not just the signal pin :p
<sorear>
so how do you remotely begin to get a calibrated signal in absolute units out of a rig like this?
<azonenberg>
The hope is that i can eventually get it flat enough that i just tell the scope it's a 10x probe and i'm good out to a couple GHz
<sorear>
is there any way to actually verify the flatness and establish an uncertainty interval around that 10?
<monochro1a>
check against a reference source
<azonenberg>
sorear: i'm testing my probe against a direct SMA feed-through
<azonenberg>
so i have a good reference to compare to
futarisIRCcloud has joined #scopehal
monochro1a is now known as monochroma
azonenberg has quit [Quit: Leaving.]
azonenberg has joined #scopehal
<azonenberg>
anyway i have some 510 bronze wire, 0.635mm diameter, inbound from McMaster-Carr and hopefully arriving tomorrow
<azonenberg>
So we'll see how that works
<azonenberg>
phosphor bronze is apparently used pretty routinely as an electrical contact material instead of BeCu
futarisIRCcloud has quit [Quit: Connection closed for inactivity]
m4ssi has joined #scopehal
marcos__ has joined #scopehal
marcos__ has quit [Quit: Konversation terminated!]
marcos__ has joined #scopehal
marcos__ has quit [Ping timeout: 272 seconds]
marcos__ has joined #scopehal
bvernoux has joined #scopehal
<bvernoux>
hello
m4ssi has quit [Remote host closed the connection]
<azonenberg>
new probe tip materials are in
<azonenberg>
have to leave for work in a few mins but trying to bang one up quick
<monochroma>
:D
<bvernoux>
ha nice
<bvernoux>
I'm impatient to know if all issues was due to tip only
<bvernoux>
evne if it seems it was the case ...
<bvernoux>
even
<azonenberg>
preliminary results: improved but still more stuff to tweak
<monochroma>
azonenberg: significant improvement?
<azonenberg>
will compare this to the direct SMA feedthrough when i get home
<azonenberg>
dont have time for a full analysis
marcos__ has quit [Ping timeout: 268 seconds]
azonenberg_work has joined #scopehal
<azonenberg_work>
So, overall signal quality with the bronze tip isnt much better than I had with the LED pins i think
<azonenberg_work>
I still like the bronze from a mechanical perspective, it's my favorite tip material so far
<azonenberg_work>
has just a little springiness to it
<azonenberg_work>
and its certainly no worse than the other materials
<azonenberg_work>
i think the next step is to play with the geometry of the tip
<bvernoux>
it is bad after 1GHZ ?
<bvernoux>
or before ?
<bvernoux>
as from 0 to 200MHz any material shall be good I think