开云体育

Really impressive work! :-)
I'm in the UK so I'll aim to find similar facility here, though I've only found fabricators who serve industry so far and I think they'll expect orders by the tonne, not a handful.

Well..... So I took the case off and checked the voltages on J119 and they are all correct according to the service manual, but I'm unclear on how exactly you go about checking the peak to peak ripple and the 2X line frequency ripple. I set everything up according to the service manual. I'll add pics to the previous folder so you can look at what I see. I almost think quite a few of these have out of tolerance ripple values, but I'm not sure. The kicker here though is that the 850 MHz trace that I had been seeing was GREATLY reduced while I had the case off and had it set up as normal, as soon as I turned it off and put the case back on it came back same as before.

Will do. Wouldn't be a huge surprise to find bad filter caps, especially if they've never been changed.

On Thu, May 15, 2025 at 9:47?AM Jason B via groups.io <sydbowen=
[email protected]> wrote:

Oh no, NVM that I see that it's one of the hybrids, not a regular IC. I
may try reseating that and see what happens. If you remove that and power
the scope up with it out of circuit will that cause any major issues? If I
can that would tell me if the oscillation is before or after that hybrid I
suppose?

IIRC the attenuators have a soldered connection to the preamps, or I would
suggest switching them to see whether the problem follows an attenuator.
All that being said, you REALLY need to check the power supplies on J119.
There's really no point to diagnosing anything else until the power
supplies have a clean-ish bill of health.

Oh no, NVM that I see that it's one of the hybrids, not a regular IC. I may try reseating that and see what happens. If you remove that and power the scope up with it out of circuit will that cause any major issues? If I can that would tell me if the oscillation is before or after that hybrid I suppose?

That was the same thing I was thinking, now I just have to figure out what.... I wonder if I can take a small loop of wire and put it near the ch 2 preamp components and narrow it down to exactly what part it is if that's what is going on...

Barry,

How do you want me to get you payment?

Mark

?? ----------------------------------.
? /? Don't take life so seriously, __/
?/?????? it's not permanent.????? /
?\_________.---------------------'
???? _ |/
??? oo\'
?? (__)\?????? _
???? \? \??? .'? `.
????? \? \? /????? \
?????? \? '"??????? \
??????? \????? (? )? \
???????? '-| )--| :.? \
?????????? | |? | | \? '.
????????? c__; c__;? '-..'>.__

Hey Jason,

From the photos you posted, I can see that:
1. The scope is triggering on the 850Mhz signal, meaning the trigger hybrid
sees it.
2. The signal is *probably* internally generated, as
/g/TekScopes/photo/302469/3916792 shows GND coupling with
the oscillation visible.

From here, in your shoes, I'd do some organized diagnosis, so if you
measure the below and report back, we can perhaps help you try and suss
what's going on.

1. What is the DC resistance of the attenuator in DC coupling?
This should be 1MOhm within 1% or so, but because of potential leakage
currents, you have to measure this both ways (DMM positive on GND then
center contact) and average. Or you can report both measurements.
You have to measure this across multiple V/DIV settings, as the attenuator
may be working right at some, but not all settings. There are two 10X
attenuator stages, so the total attenuation can be 1X, 10X or 100X, and I
think it's probably best to measure all three combos.

2. What is the DC resistance of the attenuator in AC coupling?
This should be infinite, but you can measure it at any one V/DIV setting.

3. What is the DC resistance of the attenuator in 50Ohm coupling?
This should be 50Ohm within 1% or so, you can measure this once at any
V/DIV setting.

These are all important because of the way GND coupling is implemented
(faked) on these scopes, and so these measurements only allow us to
validate whether the attenuator is working OKish.

You also probably want to pop the case off and measure the voltages on
A1J119, because if your power supplies are bad, there really is no point in
speculating about anything else until those are fixed.

My $0.02 is that your CH2 preamp is oscillating for some reason, but that's
just a guess at this point.

Good luck,
Siggi

On Wed, May 14, 2025 at 4:50?PM Jason B via groups.io <sydbowen=
[email protected]> wrote:

Okay I'll try this. I couldn't upload the vid showing me switching through
everything. Idk if any of these pics will help anyone see anything though.
/g/TekScopes/album?id=302469

I have put the Windows source code out on GitHub under the MIT license for public use. It should be fairly easy for some skilled in the art of Linux to get it running on their OS of choice. It's just a simple C program. The ugly part was trying to determine the COM port name that Windows assigns to the CurveBug. Other than that it's a matter of triggering the device to spit out a trace and then to draw the resulting graph. It uses double buffering to draw the graph off screen then swap it onto the screen in a single operation. This link will get you going if you want the challenge.

Okay I'll try this. I couldn't upload the vid showing me switching through everything. Idk if any of these pics will help anyone see anything though. /g/TekScopes/album?id=302469

Barry- those look great!!!!
搁别苍é别

They are pretty rare, particularly ones that fit a 2465x that has the DVM
option. $110 is probably as inexpensive as you will find. That's slightly
more than what I paid many years ago for my cover (but I do have the DVM
option and so expected to pay a bit more). In my mind, it's kind of like
buying the proper 'scope probes for various applications/purposes for use
with a 'scope. And a rigid front panel cover is pretty important if you are
going to transport or ship the 'scope (for calibration, for instance).

There used to be a member of either the TekScopes or TekScopes2 forums who
occasionally would sell 2465x covers.

While not as protective but just as good for keeping dust off of a 'scope,
large clear plastic bags are a temporary alternative. I have collected a
few of those over the years for use on my 7xxx and 5xx scopes.

DaveD
KC0WJN


On Wed, May 14, 2025 at 14:25 KL7AM via groups.io <w7apm=
[email protected]> wrote:

Ebay, Sphere
One on Ebay but not willing to pay a third of what I paid for the scope

----- Original Message -----
From: "Dave Daniel via groups.io" <kc0wjn@...>
To: "TekScopes" <[email protected]>
Sent: Wednesday, May 14, 2025 10:11:43 AM
Subject: Re: [TekScopes] Want Front Cover 2465b

Where have you looked?

DaveD

On 5/14/2025 1:45 PM, KL7AM via groups.io wrote:

Looking for the above

--
This email has been checked for viruses by Avast antivirus software.
www.avast.com

Ebay, Sphere
One on Ebay but not willing to pay a third of what I paid for the scope

Where have you looked?

DaveD

--
This email has been checked for viruses by Avast antivirus software.
www.avast.com

Looking for the above

Mark,

I have knobs and skirts if you need.

Barry

I got knobs and Skirts for the SC502, SC503, and SC504s.

The skirts came out perfect!

See Photos /g/TekScopes/album?id=302038

Barry

The following photos have been uploaded to the SC503 and SC504 Volts/Div and Time/Div Knob Shaft ( /g/TekScopes/album?id=302038 ) photo album of the [email protected] group.

* IMG_2585.JPG ( /g/TekScopes/photofromactivity?id=3916678 )
* IMG_2587.JPG ( /g/TekScopes/photofromactivity?id=3916679 )
* IMG_2583.JPG ( /g/TekScopes/photofromactivity?id=3916680 )

*By:* Barry Breaux <groupsio@...>

On Tue, May 13, 2025 at 11:00?AM Jason B via groups.io <sydbowen=
[email protected]> wrote:

Also I noted that on the waveform in question on the 2465, when I move the
?T markers across the waveform it distorts the waveform as I move across
the center of the screen, and the waveform disappears as I use the vertical
position control to move the trace towards the upper readout values. Does
that ring any bells to anyone here? Keep in mind also this is a 2465 with
the DMM/TV/CTT options if it's possible those options could be doing
something screwy.

From your description it's hard to say what's going on. If you've done any
of the testing suggested above, that might help you narrow down the
problem. If you report the results here, then others might help you
interpret them.
If you haven't read this document before, now might be a good time:
. Even though the
2400-series is digitally controlled, the guts are all analog goodness, so
the advice in the document applies directly.

Photos in this forum go into the photos section:
/g/TekScopes/photos, ideally in a new album with a
descriptive name. It generally helps if you then share the link to the new
album in your post, as that reduces friction for others to look at them.