Is the bandwidth limit turned on ( maybe a fault with the switching? )
The BW limit switch is off. Turning it on increases the rise time and smoothed the trace like I would expect.
Do you have any other scope with a higher bandwidth available? Some way to
verify the setup.
Yes but i checked the setup with my 468 (100 mhz) and the rise time was the correct 3.5ns
On Mon, Jun 18, 2018 at 12:34 am, Albert Otten wrote:
With curves like this
/g/TekScopes/photo/59361/1?p=Name,,,20,1,0,0 I wouldn't even
bother to calculate a rise time. Obviously the main problem is roll-off. I
would search the manual for Adjustments which influence that nanoseconds part
of the curve and try these first.
Ok. I will start turning screws. I just wanted to get opinions on whether this could possibly be a problem with a bad component prior to messing with the calibration. I would hate to have a bad transistor or capacitor causing the bad rise time and start turning the adjustments and mess up something that was actually already set correctly.
So BW = 0.35/risetime in seconds or 0.35/0.000000006 = ~~60 MHz.
The 465 should go around 100 MHz bandwidth. Around 3.5 ns.
.
----- Original Message -----
From: "lop pol via Groups.Io" <the_infinite_penguin@...>
To: <[email protected]>
Sent: Monday, June 18, 2018 12:22 AM
Subject: Re: [TekScopes] 465 bad rise time
Time div is set to .05us but I have 10x mag on so that should be 5ns.
On Sun, Jun 17, 2018 at 09:10 pm, tmillermdems wrote:
Ok, it looked like a probe at first. What is the H sweep rate set to?
Can't
see it in the pictures.
Looks like 1 1/4 divisions on the horizontal 10-90% points.
Regards
----- Original Message -----
From: "lop pol via Groups.Io" <the_infinite_penguin@...>
To: <[email protected]>
Sent: Monday, June 18, 2018 12:02 AM
Subject: Re: [TekScopes] 465 bad rise time
Im using a 50ohm cable with a 50ohm through terminator.
/g/TekScopes/photo/59361/2?p=Name,,,20,1,0,0
On Sun, Jun 17, 2018 at 08:50 pm, tmillermdems wrote:
You are looking at the waveform with a scope probe that presents a 10
meg
ohm load to the pulse generator. What you need to do is use a 50 ohm
cable
to go from the generator to the scope input and include a 50 ohm through
termination right at the scope. A real simple solution would be to use a
BNC
T with the center loaded with a 49.9 ohm resistor. Or just look for a 50
ohm
through termination on ebay.
Regards
----- Original Message -----
From: "lop pol via Groups.Io" <the_infinite_penguin@...>
To: <[email protected]>
Sent: Sunday, June 17, 2018 9:47 PM
Subject: [TekScopes] 465 bad rise time
Hey guys. I have done a lot of work to this 465. I had initially planned
on
selling it to help me buy some plugins for my 7633. I decided I don't
want
to sell it and am keeping it. Today I checked its rise time with a pg506
fast rise. Both channel 1 and 2 closely resemble each other and they are
not
close to right. Before I start trying to calibrate this thing, does it
look
like there is some type of component issue left to fix? I am thinking
since
both channels are so alike there is something wrong besides just out of
calibration. Thanks guys.
here are some pictures
/g/TekScopes/photo/59361/0?p=Name,,,20,1,0,0
/g/TekScopes/photo/59361/1?p=Name,,,20,1,0,0
