Re: Conductive Paint for Microcircuit Repair...
I have a bunch of highly conductive 2 part silver epoxy but it is past expiration date and a bit hard to mix.? It does solidify very well after mixing though.? It might work?? I have a whole bunch of the small sets of part A and B if you are inclined to want to play with some.
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On 7/16/2024 1:14 PM, Chuck Harris via groups.io wrote: Hi Peter,
The first time I tried, I used it at factory dilution.
However, over the 10 years since I did it last, the
syringes hardened... So, I reliquified them with acetone...
The acetone did a nice job of dissolving the paint, but now
it dries even faster.
So, I let (Hah! I let!) the acetone evaporate a bit, and
then replaced it with MEK, which is like acetone with a
slower evaporation rate, but, it didn't help enough.
I even thinned the stuff with MEK to 3x the volume, but the
MEK still lets the paint skin over too quickly.
I could buy new, but I would be back where I started. I was
hoping that there was a better form of the silver print.
There is a one part epoxy available, that is heat cured, but
it requires 2-300C for 15 seconds, which I think will melt
the kapton substrate.
-Chuck Harris
On Tue, 16 Jul 2024 12:44:08 -0400 "Peter Gottlieb"
<hpnpilot@...> wrote:
I have the same kind of repair to do and have not found an acceptable
solution.
Would your paint work if a little extra solvent was added and mixed
in?
Peter
On 7/16/2024 12:24 PM, Chuck Harris via groups.io wrote:
A form of silver print is what I used before, it came in
little 1ml syringes. The problem is the solvent evaporates
quickly enough that between dipping the one hair brush into
the paint, and touching the damaged spot, the paint has
skinned over, and won't transfer.
The last time I did it, I put the paint right next to the
damage, and dipped, moved 0.1", and painted. Even with that
small distance, the paint laid down like a mixture of straw
and thick mud, as the crust that formed on the wet paint on
the brush laid down in sheets and strings on the repair.
Got to be a better way!
-Chuck Harris
|
Re: Conductive Paint for Microcircuit Repair...
Years ago when I used to paint cars with laquer, thinner was available
in several grades, depending on application temperature. You wanted
the solvent to flash off in a reasonable time, not too fast and not
too slow. The grades were generally fast, medium and slow.
Well, you can still get slow laquer thinner, although I don't think
you'll like the price. However, looking up the mds shows it a near
equal combination of acetone, methanol and toluene with the remainder
mostly naptha and a teeny bit of heptane.
You might try thinning that with toluene and/or naptha and see how
it behaves.
Paul
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On Tue, Jul 16, 2024 at 12:24:56PM -0400, Chuck Harris wrote: A form of silver print is what I used before, it came in
little 1ml syringes. The problem is the solvent evaporates
quickly enough that between dipping the one hair brush into
the paint, and touching the damaged spot, the paint has
skinned over, and won't transfer.
The last time I did it, I put the paint right next to the
damage, and dipped, moved 0.1", and painted. Even with that
small distance, the paint laid down like a mixture of straw
and thick mud, as the crust that formed on the wet paint on
the brush laid down in sheets and strings on the repair.
Got to be a better way!
-Chuck Harris
--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@... | Unix/Linux - We don't do windows
|
Re: Conductive Paint for Microcircuit Repair...
Hi Peter, The first time I tried, I used it at factory dilution. However, over the 10 years since I did it last, the syringes hardened... So, I reliquified them with acetone... The acetone did a nice job of dissolving the paint, but now it dries even faster. So, I let (Hah! I let!) the acetone evaporate a bit, and then replaced it with MEK, which is like acetone with a slower evaporation rate, but, it didn't help enough. I even thinned the stuff with MEK to 3x the volume, but the MEK still lets the paint skin over too quickly. I could buy new, but I would be back where I started. I was hoping that there was a better form of the silver print. There is a one part epoxy available, that is heat cured, but it requires 2-300C for 15 seconds, which I think will melt the kapton substrate. -Chuck Harris On Tue, 16 Jul 2024 12:44:08 -0400 "Peter Gottlieb" <hpnpilot@...> wrote: I have the same kind of repair to do and have not found an acceptable
solution.
Would your paint work if a little extra solvent was added and mixed
in?
Peter
On 7/16/2024 12:24 PM, Chuck Harris via groups.io wrote:
A form of silver print is what I used before, it came in
little 1ml syringes. The problem is the solvent evaporates
quickly enough that between dipping the one hair brush into
the paint, and touching the damaged spot, the paint has
skinned over, and won't transfer.
The last time I did it, I put the paint right next to the
damage, and dipped, moved 0.1", and painted. Even with that
small distance, the paint laid down like a mixture of straw
and thick mud, as the crust that formed on the wet paint on
the brush laid down in sheets and strings on the repair.
Got to be a better way!
-Chuck Harris
|
Hello Wayne,
I have an 8702A which?IIRC is an 8753C with firmware to support the optical function by using the optical S parameter test set (which I do not have). Apparently one could mix optical and electrical measurements with the proper test set but I just select?electrical as I only have the S Parameter test set for electrical.?
AFAIK the base electronics hardware on the 8702A and the 8753 are identical only the firmware is different so if you can find a manual for the 8753 you should be good to go. As far as the external display goes I don't know but I believe some members on the EEVblog forum site have converted the 8753's to an LCD display so that might be an option for you.
Sam W3OHM
Sam Reaves
ARS W3OHM
Owner / Moderator of: LeCroy Owners Group on Groups.io
Sencore Owners Group on Groups.io Sprint Layout Group on Groups.io?? Pulsonix EDA Group on Groups.io
LPKF Owners Group on Groups.io
Electronics and Mechanical Hardware Design Engineering Manager
Staff Scientist Andritz Rolls Global Research Center (RETIRED)
|
Re: Conductive Paint for Microcircuit Repair...
I have the same kind of repair to do and have not found an acceptable solution.
Would your paint work if a little extra solvent was added and mixed in?
Peter
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Show quoted text
On 7/16/2024 12:24 PM, Chuck Harris via groups.io wrote: A form of silver print is what I used before, it came in
little 1ml syringes. The problem is the solvent evaporates
quickly enough that between dipping the one hair brush into
the paint, and touching the damaged spot, the paint has
skinned over, and won't transfer.
The last time I did it, I put the paint right next to the
damage, and dipped, moved 0.1", and painted. Even with that
small distance, the paint laid down like a mixture of straw
and thick mud, as the crust that formed on the wet paint on
the brush laid down in sheets and strings on the repair.
Got to be a better way!
-Chuck Harris
On Tue, 16 Jul 2024 10:33:52 -0400 "Michael A. Terrell"
<terrell.michael.a@...> wrote:
I used to use General Cement Silver Print to repair conductive
traces. I believe it was a lacquer with very fine silver particles in
suspension. I don't know if it is still available, because my
satellite internet can take an hour and a dozen tries to open most
web pages. during the day. It is to be replaced by a fiber optic
service, but that hasn't happened yet.
On Tue, Jul 16, 2024 at 8:55?AM Chuck Harris via groups.io <cfharris=
[email protected]> wrote:
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs. The whole
operation was right at the limits of my abilities to manipulate
things by hand. Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over. I got the job
done before, but it looked like a clotted mess.
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like. The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Re: Conductive Paint for Microcircuit Repair...
A form of silver print is what I used before, it came in little 1ml syringes. The problem is the solvent evaporates quickly enough that between dipping the one hair brush into the paint, and touching the damaged spot, the paint has skinned over, and won't transfer. The last time I did it, I put the paint right next to the damage, and dipped, moved 0.1", and painted. Even with that small distance, the paint laid down like a mixture of straw and thick mud, as the crust that formed on the wet paint on the brush laid down in sheets and strings on the repair. Got to be a better way! -Chuck Harris On Tue, 16 Jul 2024 10:33:52 -0400 "Michael A. Terrell" <terrell.michael.a@...> wrote: I used to use General Cement Silver Print to repair conductive
traces. I believe it was a lacquer with very fine silver particles in
suspension. I don't know if it is still available, because my
satellite internet can take an hour and a dozen tries to open most
web pages. during the day. It is to be replaced by a fiber optic
service, but that hasn't happened yet.
On Tue, Jul 16, 2024 at 8:55?AM Chuck Harris via groups.io <cfharris=
[email protected]> wrote:
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs. The whole
operation was right at the limits of my abilities to manipulate
things by hand. Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over. I got the job
done before, but it looked like a clotted mess.
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like. The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Re: Conductive Paint for Microcircuit Repair...
I used to use General Cement Silver Print? to repair conductive traces. I believe it was a lacquer with very fine silver particles in suspension. I don't know if it is still available, because my? satellite internet can take an hour and a dozen tries to open most web pages. during the day. It is to be replaced by a fiber optic service, but that hasn't? happened yet.
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs.? The whole
operation was right at the limits of my abilities to manipulate
things by hand.? Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over.? I got the job
done before, but it looked like a clotted mess.?
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like.? The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Re: Conductive Paint for Microcircuit Repair...
Ok. I saw the arm-hair statement, but not the fact that that was the width of the trace.
Thanks.
DaveD
KC0WJN
==============================
All spelling mistakes are the responsibilty of the reader (Rick Renz, STK, ca. 1994)
==============================
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On Jul 16, 2024, at 09:50, Chuck Harris via groups.io <cfharris@...> wrote:
?As I stated in my original post, about 0.04mm, or one of
my arm hairs.
-Chuck Harris
On Tue, 16 Jul 2024 09:47:12 -0400 "Dave Daniel" <kc0wjn@...>
wrote:
What is the width of the flex cable trace under discussion?
DaveD
KC0WJN
==============================
All spelling mistakes are the responsibilty of the reader (Rick Renz,
STK, ca. 1994) ==============================
|
Re: Conductive Paint for Microcircuit Repair...
As I stated in my original post, about 0.04mm, or one of my arm hairs. -Chuck Harris On Tue, 16 Jul 2024 09:47:12 -0400 "Dave Daniel" <kc0wjn@...> wrote: What is the width of the flex cable trace under discussion?
DaveD
KC0WJN
==============================
All spelling mistakes are the responsibilty of the reader (Rick Renz,
STK, ca. 1994) ==============================
|
Re: Conductive Paint for Microcircuit Repair...
What is the width of the flex cable trace under discussion?
DaveD
KC0WJN
==============================
All spelling mistakes are the responsibilty of the reader (Rick Renz, STK, ca. 1994)
==============================
toggle quoted message
Show quoted text
On Jul 16, 2024, at 09:45, Chuck Harris via groups.io <cfharris@...> wrote:
?Hmmm?
"Masking" tape is generally made of crepe paper that
has crenulations that are bigger than my entire trace
width.
I suppose some kapton tape pieces could be arranged to
make some sort of mask...
Thanks for the idea... I will think on it.
-Chuck Harris
On Tue, 16 Jul 2024 08:07:06 -0500 "Dave Casey" <polara413@...>
wrote:
Use masking tape to define your trace width.
Dave Casey
On Tue, Jul 16, 2024, 7:55 AM Chuck Harris via groups.io <cfharris=
[email protected]> wrote:
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs. The whole
operation was right at the limits of my abilities to manipulate
things by hand. Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over. I got the job
done before, but it looked like a clotted mess.
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like. The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Re: Conductive Paint for Microcircuit Repair...
Hmmm? "Masking" tape is generally made of crepe paper that has crenulations that are bigger than my entire trace width. I suppose some kapton tape pieces could be arranged to make some sort of mask... Thanks for the idea... I will think on it. -Chuck Harris On Tue, 16 Jul 2024 08:07:06 -0500 "Dave Casey" <polara413@...> wrote:
Use masking tape to define your trace width.
Dave Casey
On Tue, Jul 16, 2024, 7:55 AM Chuck Harris via groups.io <cfharris=
[email protected]> wrote:
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs. The whole
operation was right at the limits of my abilities to manipulate
things by hand. Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over. I got the job
done before, but it looked like a clotted mess.
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like. The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
HP 8557A Start-Up Calibration & Linear Mode - Errors in Manual?
Hey y'all!? I was hoping to get some help or clarification on the start-up calibration procedure for the HP 8557A/8558B spectrum analyzer plug-in.? First, I did not get this unit in working order and I have completed a lot of restoration on it. Also, I've never used/owned a spectrum analyzer before this unit, which likely contributes to the trouble I'm having.?
?
The problem I'm having is with the linear/10 dB/div calibration.? In this step, the manual states that you should be able to adjust both the Linear and 10dB/div by adjusting the 'Reference Level Fine' knob to get the 250MHz calibration signal peak all the way to the top graticule line.? But I can't do that without adjusting the 'Coarse reference level' knob (the manual does allude to using the coarse reference level knob for this adjustment in the troubleshooting section of the manual).? The manual states if this adjustment cannot be done, then check the linear/log amplifier board A11, but I can't find any issues there.
?
My question is, can anyone who owns one of these make sense of the manual?? Or possibly have they confirmed an issue with the way it is described?? It seems a blog on repairing this instrument (pretty much the same repair I had to perform) also seems to allude to issues with the manual.? My cal signal and amplitude for both linear and log modes looks similar to his (blog link here; scroll to the bottom )
?
Thanks in advance for your help!
?
-Frank
|
Re: Conductive Paint for Microcircuit Repair...
Use masking tape to define your trace width.
Dave Casey?
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs.? The whole
operation was right at the limits of my abilities to manipulate
things by hand.? Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over.? I got the job
done before, but it looked like a clotted mess.?
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like.? The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Conductive Paint for Microcircuit Repair...
Hi Gang,
I need a workable conductive paint for use on repairing a
really tiny flexible circuit board trace.
Due to a flaw in manufacturing, a small bit (about the diameter
of a human hair) of a conductive trace is once again missing.
About 10 years ago, I fixed the problem with a conductive silver
paint, and a brush made from one of my arm hairs. The whole
operation was right at the limits of my abilities to manipulate
things by hand. Now, it is 10 years later...
The first time, I was vexed by the quickness with which the
paint's solvent evaporated, and skinned over. I got the job
done before, but it looked like a clotted mess.
What I would like is a one part conductive paint that flows, and
works like water or ink, but has a working time of 30 seconds, or
so... while making a hair thick trace... which isn't quite the
same thing as making a 1/16th in brush stroke...
Conductive thermosetting epoxies look promising, but I don't know
how they were meant to be applied, or what working with them is
like. The board is orange, like kapton (polyamide), but I don't
really know what its temperature limits are.
The trace is exactly the same width as one of my descended from
northern European diaspora arm hairs... about 0.04mm.
Ideas?
-Chuck Harris
|
Re: 8702A service manual [SEC=UNOFFICIAL]
Yes I am getting that feeling. The 8702A uses a vector display and not RGB? like the later models. one of the Simmconn kits looks like it is the only way to go unless there are boards I can swap out to upgrade the 8702A to a later model, which I doubt. Is there any benefit in changing firmware from 8702A to 8753 as far as functionality? for electrical testing?
I did find the 8753 manuals , but not much info on teh video side. worked out? that the
8702A uses 1349A display unit, but not an easy or cheap upgrade to an LCD :(
|
Re: VNA calibration kit to 50 GHz
finding in addition that a 1-port Open, Short, Load (OSL) calibration is difficult in waveguide due to the problem of getting the Open, so this in waveguide seems to be replaced with SSL, where S=O= l/8, S= 3 l/8, L=matched load. However, why you can¡¯t use a flush short and a l/4 short I don¡¯t know.
?
Another website said the SSL for 1-port could be extended to 2-ports by making the SSL for each port separately, then making a T (thru) calibration in the usual way by just connecting the waveguide ends together, this being referred to as a SSLT calibration, where S= 3l/8, and O= l/8, with L being matched load and T being thru. Again why the S and S cant be a waveguide flush short and = l/4 short I don¡¯t know.
?
However, it would be interesting to hear a comment from those who use the ?l/8, S= 3l/8 waveguide spacers for calibration2.
|
Re: HP 83590A RF plugin EPROM image
Hi,
?
The firmware for the 83590A I downloaded is not working I'm afraid. When installed the 8350B does not recognize the plugin and stops with a "E001" error.
?
The first bytes of the firmware should (according to the service manual) always be "55" and then "AA". I think the startup check looks for that signature specifically and then does a checksum. This firmware does not have that (it starts "55A8") and so will not work. I'm wondering if the ROM image export was corrupted?
?
Are any other 83590A ROM image files available?
?
many thanks
?
Tony
?
|
Re: HP 83590A - Help understanding frequency band switching
Hi Don,
?
Yes, I've been going through the service manual reviewing both the theory of operation and detailed per-assembly explanations. Thanks for the confirmation re. Band 0/4. I'm still a bit puzzled that there is no reference to Band 2 in the schematics, given that the YTM is involved in the x2 frequency multiplication.
?
I'm going through the adjustments process in the service manual (it seems like a good way to work out at what point things are not working).? Unfortunately things go off track quite quickly. I'm attempting to adjust the variable gain amplifier to ensure the bandswitch points are correct - and while I can adjust the lower frequency 7GHz point correctly, the upper 13.5GHz cannot be set becasue there is not enough adjustment on the potentiometers.
?
thanks
?
Tony
?
|
Re: 8702A service manual [SEC=UNOFFICIAL]
Found the service manual for the 8753, thanks ,didn't see anything regarding the video, will delve deeper into it today. One of the 8702's has arcing in the eht but haven't taken
the covers off yet. The other seems to be working fine, but with old age( mine), the display is getting harder to read.
IS there any advantage I over the 8702 n installing the 8753 firmware as I am only doing RF work, not optical. I have 3 different S parameter test sets, including 1 x 75 ohm model(
still in storage so can't remember the model number).
?
Wayne
?
?
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Show quoted text
From: [email protected]
<[email protected]> On Behalf Of Jim n8qoh
Sent: Tuesday, July 16, 2024 12:10 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] 8702A service manual
?
I believe the 8702A is an 8753C with different firmware (display is color).? Find the video, pick it off and feed it into a Gonbes video converter (or similar) from eBay.? You may need to add an LM1881 sync seperator
depending on which scan converter you choose.
I don¡¯t know of a dedicated service manual for the 8702A. These units are essentially a 8753A with modified firmware for fibre testing with the additional light bridge. ?
There are 8753A service manuals online.?
After having a search, it appears that connecting a external monitor won¡¯t be easy. You may have to use something like a Simmconn Lab LCD conversion to get external monitor capabilities.
|
Re: 8640B won't switch to highest +20 dBm range
Hello Dave, Your diagnosis suggests the attenuator knob and switch is out by one detent. 73 de Brian, VK2GCE
----- Original Message -----
To: <[email protected]>
Cc:
Sent: Mon, 15 Jul 2024 15:48:36 -0700
Subject: [HP-Agilent-Keysight-equipment] 8640B won't switch to highest +20 dBm range
I just purchased a pretty clean 8640B signal generator, but it has a couple of little problems. I already fixed a loose set screw down inside on the option 001 variable audio oscillator and will be adjusting and calibrating the audio oscillator tomorrow.
?
It also has an 003 option and 2232A serial prefix.
?
But I am having a problem with the RF output step attenuator where it won't switch to the highest +20 dBm range, but will switch 1 step below the lowest -130 dBm setting, though that causes the output meter level to drop to zero.?
?
The upper ranges check as perfectly calibrated to a fairly new digital oscilloscope and within a dB or so to a TinySA ULTRA spectrum analyzer. It appears that someone has had the attenuator housing open as evidenced buy an original HP paper sticker that has been sliced along a seam.
?
It seems an odd situation, but does anyone have an idea what is going on? Unless I get a better clue, I plan to pull the attenuator out and open it up tomorrow.?
?
Thanks
Email sent using Optus Webmail
|
Sam Reaves
Michael A. Terrell
Frank Mashockie
Brian