Re: Analog vs Digital Oscilloscopes
Ok, that just BEGS the question: ?What do any of us *amateurs* need such a fast scope for? ?DIY Nuclear physics experiments? ?Home brew nuclear bomb igniters? ?Ultra fast laser pulses? ?Time of Flight experiments? ? I'm curious to do a quick survey.
I'm a *professional* and work for a small company that makes mm-wave devices and the fastest scope we have, need or want at work has about a 100MHz bandwidth. ??
At home, I've used my 7854 to observe the pulses from a Tektronix type 109 pulse generator that I found and repaired, but that was just for fun and curiosity. ?It's not the main thrust of any of my hobbies (other than electronics). ? And yes, I know, wrong group, so I've cross-posted... and probably hijacked the thread by accident.
? But seriously, what are folks our there doing with their scopes, at the highest frequency bandwidth they've needed, whether they be digital or analog?
? Dan
On Friday, July 21, 2017 1:10 PM, "Harvey White madyn@... [hp_agilent_equipment]" wrote:
?
On Fri, 21 Jul 2017 16:39:54 +0000 (UTC), you wrote:
>Hmmm.... makes me want to get one. ?they are within reach on e-bay.... but NO. ? I can't expand anymore. ?I'll stick to my "slow" 7854.
The 710x series is that fast, but the CRT has a limited life due to
the MCP. It doesn't make a good bench scope unless you need what it
does (intensifying a very low duty cycle aberrant pulse, for
instance).
I have one, needs a slight amount of fixing, but I don't intend to use
it unless I really need what it does.
Harvey
|
Re: Analog vs Digital Oscilloscopes
Peter said
"Perhaps that may be due to the lack of reasonable international cost
shipping options and the relative fragility of the instruments. "
I think it's historic export control. MCPs are used in night vision equipment and even ordinary very high speed scopes were (are) export controlled by the USA. see item "Components with Nuclear Weapons Applications to Pakistan
& India" here
Robert G8RPI.
|
Re: HP-3586B PS problem - connector J2 overheating
Bill,?
Thanks for that very practical recommendation regarding the Molex connector issue with overheating. ?Soldering. There are still 14 pins on the PS motherboard and I presume that the soldering would have to be done under that board where the pins are connected to the board. Otherwise, I would use a new connector with the accompanying wires to plug into the 14 pins and then solder those wires to wires on the transformer side after cutting off the bad connector. ?I have not looked at the connections under the PS board to see if they are solderable or not. I know that this is not very clear, but I can see the point of preventing any future overheating of the connection by soldering.?
That was very interesting about the foam gas problem that affected the knobs. I noticed it on my HP-3702B and 3712A as well as some of the transmitters and receivers that I have that measure microwave channel distortion and a lot of other microwave transmission parameters that I don't really understand.
I acquired this equipment as a lot from a microwave facility workshop that had shut down around 2005. Out of the lot I was able to resuscitate a signal gen (HP-3336B), a spectrum analyzer (8659B), a power meter (432A), two selective level meters (3586B) and another SLM, a (3746A). There were also a couple of frequency meters (5342As), a live one and a dead one. The live one is still dodgy and still beyond my capacity fix properly.?
They are all useful on the ham bench and all are within calibration tolerances that are acceptable for 'hobby use', as I call it. They all had service tags when I got my hands on them and all had minor problems. It appears that true microwave engineers will service tag anything that is not within .0001% of NIST standards. Hi. Level measuring was little affected by age, in my opinion, but frequency calibration was another story, of course. Aging had put frequency calibration all over the map, but by using a cheap GPS driven frequency standard I was able to get them all back within a Hz or so of each other and WWV. I used the 3586B and 3336B to approximate the frequency measuring setup of Bert's (K6OQK -?) and can measure frequencies on the air to near Hz standard, perhaps even sub-Hz, but I can't really be certain of that.?
Now the other HP test equipment, that made up most of the lot, was for microwave transmission testing involving baseband measuring, channel distortion, 70, 140 Mhz (+/- 30) signals etc. My question is how, if possible, could any of those transmitters and receivers be used on the bench for conventional electronic applications involving ham radio, kit building or testing of any kind. I have a rough idea how those systems work, but no idea how to apply or use this equipment in any useful way. Next step is to go for the great quality internal ?parts.?
In mentioning the knobs and the crumbling problem I did not mean to imply in any way the HP gear is cheaply made or not very durable. The knobs were an exception. I got started with this test equipment collection business in Cairo when I was living there for many years. I found out that some foreigners in our community would go to the City of the Dead Flea Market every Friday and pick up cheap antiques. I started going myself and found that every manner of electronic device manufactured over 60 years could turn up there in varying degrees of condition.?
Over a period of about ten years there was not much in the way of ham equipment and testing gear I did not find there: Collins, Heathkit, Harris, Hallicrafters, Tek, 20s and 30s AM radios, Russian electronics (a lot of it and very poorly made), and so many parts. I took everything home that might have parts in it and I built a lot gear on the bench with those parts (I did not have a ham license there until the very end - SU9AM). So the HP gear, by far, providing the best quality parts, particularly tuning capacitors and coils.
I used a recovered ?651B test oscillator for my signal generator and when I could no longer keep that running I used it's amazing tuning capacitor in a home brew VFO. One day at the bottom of a large pile of trash I spotted what looked like something HP. I had some help digging it out and found it was an 141T mainframe with two plugins. I had no idea what it was, but the screen was not broken or cracked so I took it home. It was pretty bent up and one of the plugins had damage near one of the knobs. It was also filthy. I obtained a schematic off the net and over the next few months after rewiring a plugin switch and doing some other basic maintenance and alignment I got it running again. It was good enough to bring home with me.
I brought home all my HP carcasses', as I called them, for spares. What I found in general was that at the City of the Dead most of the equipment that had been thrown away had been so because of minor faults, simple things like bad switches or even blown fuses. The locals in government who used this equipment did not have much in the way of budget for training or maintenance and if something failed the first response would be to throw it out and take a new one off the shelf. The new one off the shelf usually had been paid for by USAID ( our taxes) or some other donor. That was good news for me.?
The most interesting finds there were probably a complete telephone kiosk from Orange County,CA with the 714 number still on the phone and a "Russian nose cone from a Mig fighter with the avionics still inside. Close behind were all the golf bags with clubs from all the golf courses around the U.S. Egyptian friends have told me that Cairo Airport left luggage is where just about everything that's lost in air travel ends up eventually. And I can tell you from experience that anything that is thrown out of a household (or stolen out of left luggage) in Egypt that is in anyway still usable 'in any way' ends up at the City of the Dead also.?
Sorry about the long post. Thanks for the suggestion on the connector problem.?
Jim? W3BH
??
?
|
Re: Analog vs Digital Oscilloscopes
Office, son¡¯s old room, garden shed, lockup. ? A case of strong TEA. ? Craig ?
toggle quoted message
Show quoted text
From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: 21 July 2017 18:31
To: hp_agilent_equipment@...
Subject: RE: [hp_agilent_equipment] Analog vs Digital Oscilloscopes?
A serious case of TEA (Test Equipment Acquisition syndrome) J ? Dave ? ?
Hello, same problem here - I ran out of lab space. But I will buy a bigger lab soon ;) ? Tam
|
Re: Help needed with HP Pin diode.
?
?I have a Schlumberger 4002 signal generator, I
need help with a pin diode in this unit.
The pin diode is QPND 4709?(HP manuafacture), I can't find it anywhere,
I am looking for this or a replacement for it, would
like a non smd, since layout is for leaded axial type. I
have no experience with pin diodes and need help. The
pin diodes is used for AM modulation and level
adjustment of the carrier, please see the schematic I
attached.?
Thank you.
Rgds
Henrik
This is the output when I try and open this file:
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on line 122
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in /code/pb-htdocs/public/galleryd/index.php on line 122
|
Re: Analog vs Digital Oscilloscopes
A serious case of TEA (Test Equipment Acquisition syndrome) J ? Dave ?
toggle quoted message
Show quoted text
From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: 21 July 2017 17:41
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] Analog vs Digital Oscilloscopes?
Hello, same problem here - I ran out of lab space. But I will buy a bigger lab soon ;) ? Tam
|
Re: Analog vs Digital Oscilloscopes
On Fri, 21 Jul 2017 16:39:54 +0000 (UTC), you wrote: Hmmm.... makes me want to get one. ???they are within reach on e-bay.... but NO. ??? I can't expand anymore. ???I'll stick to my "slow" 7854. The 710x series is that fast, but the CRT has a limited life due to the MCP. It doesn't make a good bench scope unless you need what it does (intensifying a very low duty cycle aberrant pulse, for instance). I have one, needs a slight amount of fixing, but I don't intend to use it unless I really need what it does. Harvey ??? Dan
On Friday, July 21, 2017, 9:05:59 AM EDT, Chuck Harris cfharris@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
???
Hi Dan,
I think there is a math error, but its only physics, so
close is pretty good.
That is why I said "The 7104... operates in this region".
Imagine what would have come next if tektronix had made
the next generation leap with the MCP.
The horizontal sweep is not even close to the fastest thing
the 7104 does with its beam... sweep is a pretty slow function
for any scope...
For example, the 7104 travels the beam about 8 divisions in
300ps in the vertical direction, while sweeping 200ps/division
in the horizontal direction... the diagonal speed is pretty
spritely.
And, there is an OEM version of the 7104 that is 3x that
fast. All these speeds are limited by the amplifiers, not
the CRT... The CRT is about another 2x that fast.
Additionally, just because an electron in the beam is launched,
doesn't mean it gets multiplied in the MCP...its only those that
happen to hit an active spot on the MCP's walls at just the
right angle that get multiplied.
Interesting to think about... don't you think?
As to the question about speckle, yep, there is a grainy
character to all of the cells that show on the screen. If
you adjust the internal "MCP Output" pot, you can make the
screen scintillate quite nicely. Go the other direction,
and you can make the beam only show the very hottest electrons
that went down the pipe, making the trace very grainy.
If the 7104 wasn't so rare, it would make quite a nice little
physics experiment.
-Chuck Harris
Daniel Koller kaboomdk@... [hp_agilent_equipment] wrote:
Hi Chuck, Almost, but not quite. I don't know what the electron beam current of a
7104 CRT is. Let's assume 1 microamp (that's probably a low estimate), so 6.24E18
electrons per Coulomb x 1E-6 C/ s = 6.24E12 electrons per second. Fastest
sweep on a 7104/7B10 is 200pS per division, x10 setting, so 20pS per division.
6.24E12 Electrons per sec x 20E-12 = 125 electrons per division..... Wow, you are
right. It would be hard to resolve on a regular CRT and the MCP bins them and
multiplies them of course, but it's almost discrete. However, the uncertainty
principle will make sure that we can't predict when they leave the electron gun
thus blurring any spots on the screen... Is there speckle on the the MCP CRTs?
Dan
On Thursday, July 20, 2017, 4:32:45 PM EDT, Chuck Harris cfharris@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
Go fast enough, or small enough, and everything becomes discrete.
That should light a fire!
For example, if you take a standard electron beam, ala a CRT, and sweep the beam
quickly enough, you can get to a speed where the electron beam looks similar to
what you would have with a rapid fire BB gun.. Each electron represented by a BB.
The electrons will land in discrete spots on the screen. The 7104, with its MCP,
operates in this region.
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|
Re: Analog vs Digital Oscilloscopes
Hello,
same problem here - I ran out of lab space. But I will buy a
bigger lab soon ;)
Tam
With best regards
Tam Hanna
---
NEW: Enjoy electronics? Like seeing oscilloscopes get repaired? Please subscribe to my new YouTube channel ->
On 21.07.2017 18:39, Daniel Koller
kaboomdk@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
?
Hmmm.... makes me want to get one. ?they are within
reach on e-bay.... but NO. ? I can't expand anymore.
?I'll stick to my "slow" 7854.
? Dan
On Friday, July 21, 2017, 9:05:59 AM EDT, Chuck
Harris cfharris@... [hp_agilent_equipment]
wrote:
?
Hi Dan,
I think there is a math error, but its
only physics, so
close is pretty good.
That is why I said "The 7104... operates
in this region".
Imagine what would have come next if
tektronix had made
the next generation leap with the MCP.
The horizontal sweep is not even close
to the fastest thing
the 7104 does with its beam... sweep is
a pretty slow function
for any scope...
For example, the 7104 travels the beam
about 8 divisions in
300ps in the vertical direction, while
sweeping 200ps/division
in the horizontal direction... the
diagonal speed is pretty
spritely.
And, there is an OEM version of the 7104
that is 3x that
fast. All these speeds are limited by
the amplifiers, not
the CRT... The CRT is about another 2x
that fast.
Additionally, just because an electron
in the beam is launched,
doesn't mean it gets multiplied in the
MCP...its only those that
happen to hit an active spot on the
MCP's walls at just the
right angle that get multiplied.
Interesting to think about... don't you
think?
As to the question about speckle, yep,
there is a grainy
character to all of the cells that show
on the screen. If
you adjust the internal "MCP Output"
pot, you can make the
screen scintillate quite nicely. Go the
other direction,
and you can make the beam only show the
very hottest electrons
that went down the pipe, making the
trace very grainy.
If the 7104 wasn't so rare, it would
make quite a nice little
physics experiment.
-Chuck Harris
Daniel Koller kaboomdk@...
[hp_agilent_equipment] wrote:
> Hi Chuck, Almost, but not quite. I
don't know what the electron beam
current of a
> 7104 CRT is. Let's assume 1
microamp (that's probably a low
estimate), so 6.24E18
> electrons per Coulomb x 1E-6 C/ s =
6.24E12 electrons per second. Fastest
> sweep on a 7104/7B10 is 200pS per
division, x10 setting, so 20pS per
division.
> 6.24E12 Electrons per sec x 20E-12
= 125 electrons per division..... Wow,
you are
> right. It would be hard to resolve
on a regular CRT and the MCP bins them
and
> multiplies them of course, but it's
almost discrete. However, the
uncertainty
> principle will make sure that we
can't predict when they leave the
electron gun
> thus blurring any spots on the
screen... Is there speckle on the the
MCP CRTs?
> Dan
>
>
> On Thursday, July 20, 2017, 4:32:45
PM EDT, Chuck Harris cfharris@...
> [hp_agilent_equipment]
wrote:
>
>
> Go fast enough, or small enough,
and everything becomes discrete.
>
> That should light a fire!
>
> For example, if you take a standard
electron beam, ala a CRT, and sweep the
beam
> quickly enough, you can get to a
speed where the electron beam looks
similar to
> what you would have with a rapid
fire BB gun.. Each electron represented
by a BB.
> The electrons will land in discrete
spots on the screen. The 7104, with its
MCP,
> operates in this region.
>
>
>
>
>
>
|
Re: Analog vs Digital Oscilloscopes
Hmmm.... makes me want to get one. ?they are within reach on e-bay.... but NO. ? I can't expand anymore. ?I'll stick to my "slow" 7854.
? Dan
On Friday, July 21, 2017, 9:05:59 AM EDT, Chuck Harris cfharris@... [hp_agilent_equipment]
?
Hi Dan,
I think there is a math error, but its only physics, so
close is pretty good.
That is why I said "The 7104... operates in this region".
Imagine what would have come next if tektronix had made
the next generation leap with the MCP.
The horizontal sweep is not even close to the fastest thing
the 7104 does with its beam... sweep is a pretty slow function
for any scope...
For example, the 7104 travels the beam about 8 divisions in
300ps in the vertical direction, while sweeping 200ps/division
in the horizontal direction... the diagonal speed is pretty
spritely.
And, there is an OEM version of the 7104 that is 3x that
fast. All these speeds are limited by the amplifiers, not
the CRT... The CRT is about another 2x that fast.
Additionally, just because an electron in the beam is launched,
doesn't mean it gets multiplied in the MCP...its only those that
happen to hit an active spot on the MCP's walls at just the
right angle that get multiplied.
Interesting to think about... don't you think?
As to the question about speckle, yep, there is a grainy
character to all of the cells that show on the screen. If
you adjust the internal "MCP Output" pot, you can make the
screen scintillate quite nicely. Go the other direction,
and you can make the beam only show the very hottest electrons
that went down the pipe, making the trace very grainy.
If the 7104 wasn't so rare, it would make quite a nice little
physics experiment.
-Chuck Harris
Daniel Koller kaboomdk@... [hp_agilent_equipment] wrote:
> Hi Chuck, Almost, but not quite. I don't know what the electron beam current of a
> 7104 CRT is. Let's assume 1 microamp (that's probably a low estimate), so 6.24E18
> electrons per Coulomb x 1E-6 C/ s = 6.24E12 electrons per second. Fastest
> sweep on a 7104/7B10 is 200pS per division, x10 setting, so 20pS per division.
> 6.24E12 Electrons per sec x 20E-12 = 125 electrons per division..... Wow, you are
> right. It would be hard to resolve on a regular CRT and the MCP bins them and
> multiplies them of course, but it's almost discrete. However, the uncertainty
> principle will make sure that we can't predict when they leave the electron gun
> thus blurring any spots on the screen... Is there speckle on the the MCP CRTs?
> Dan
>
>
> On Thursday, July 20, 2017, 4:32:45 PM EDT, Chuck Harris cfharris@...
> [hp_agilent_equipment] wrote:
>
>
> Go fast enough, or small enough, and everything becomes discrete.
>
> That should light a fire!
>
> For example, if you take a standard electron beam, ala a CRT, and sweep the beam
> quickly enough, you can get to a speed where the electron beam looks similar to
> what you would have with a rapid fire BB gun.. Each electron represented by a BB.
> The electrons will land in discrete spots on the screen. The 7104, with its MCP,
> operates in this region.
>
>
>
>
>
>
|
Re: Analog vs Digital Oscilloscopes
Perhaps that may be due to the lack of reasonable international cost shipping options and the relative fragility of the instruments.?
Peter
toggle quoted message
Show quoted text
?
>7103/4's aren't that rare, see them all the time at fleas for $100-300 and usually with plugins.
That might well be the situation in the US; they are as rare as hen's teeth elsewhere on the planet.
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Hi George... So there is no access to the local oscillator without adding option 010? Is the only option for a TG the official HP module? / Gerry
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Re: Analog vs Digital Oscilloscopes
7103/4's aren't that rare, see them all the time at fleas for $100-300 and usually with plugins. That might well be the situation in the US; they are as rare as hen's teeth elsewhere on the planet.
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Re: Help needed with HP Pin diode.
?
Hi Henrik if you want a simple single wire ended
pin diode you might find something like the older 5082-3001 or 3002 might work
in that application. They are only specc'd down to 10MHz in my very old HP book
(Aug 1967 !!) but should work as a modulator down to 1MHz because you can use
normal HS diodes for that. The pins will be better at the high frequency
end.
?
Alan
G3NYK
?
?
----- Original Message -----
Sent: Friday, July 21, 2017 10:17
AM
Subject: [hp_agilent_equipment] Help
needed with HP Pin diode.
?I have a Schlumberger 4002 signal generator, I need help with a
pin diode in this unit.
The pin diode is QPND 4709?(HP manuafacture), I can't find it anywhere, I am looking for this
or a replacement for it, would like a non smd, since layout is for leaded
axial type. I have no experience with pin diodes and need help. The pin diodes
is used for AM modulation and level adjustment of the carrier, please see the
schematic I attached.?
Thank you.
Rgds
Henrik
?
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Re: Analog vs Digital Oscilloscopes
7103/4's aren't that rare, see them all the time at fleas for $100-300 and usually with plugins.?
I only have the R7103 as I wanted that form factor.?
Peter
toggle quoted message
Show quoted text
?
Hi Dan,
I think there is a math error, but its only physics, so
close is pretty good.
That is why I said "The 7104... operates in this region".
Imagine what would have come next if tektronix had made
the next generation leap with the MCP.
The horizontal sweep is not even close to the fastest thing
the 7104 does with its beam... sweep is a pretty slow function
for any scope...
For example, the 7104 travels the beam about 8 divisions in
300ps in the vertical direction, while sweeping 200ps/division
in the horizontal direction... the diagonal speed is pretty
spritely.
And, there is an OEM version of the 7104 that is 3x that
fast. All these speeds are limited by the amplifiers, not
the CRT... The CRT is about another 2x that fast.
Additionally, just because an electron in the beam is launched,
doesn't mean it gets multiplied in the MCP...its only those that
happen to hit an active spot on the MCP's walls at just the
right angle that get multiplied.
Interesting to think about... don't you think?
As to the question about speckle, yep, there is a grainy
character to all of the cells that show on the screen. If
you adjust the internal "MCP Output" pot, you can make the
screen scintillate quite nicely. Go the other direction,
and you can make the beam only show the very hottest electrons
that went down the pipe, making the trace very grainy.
If the 7104 wasn't so rare, it would make quite a nice little
physics experiment.
-Chuck Harris
Daniel Koller kaboomdk@... [hp_agilent_equipment] wrote:
> Hi Chuck, Almost, but not quite. I don't know what the electron beam current of a
> 7104 CRT is. Let's assume 1 microamp (that's probably a low estimate), so 6.24E18
> electrons per Coulomb x 1E-6 C/ s = 6.24E12 electrons per second. Fastest
> sweep on a 7104/7B10 is 200pS per division, x10 setting, so 20pS per division.
> 6.24E12 Electrons per sec x 20E-12 = 125 electrons per division..... Wow, you are
> right. It would be hard to resolve on a regular CRT and the MCP bins them and
> multiplies them of course, but it's almost discrete. However, the uncertainty
> principle will make sure that we can't predict when they leave the electron gun
> thus blurring any spots on the screen... Is there speckle on the the MCP CRTs?
> Dan
>
>
> On Thursday, July 20, 2017, 4:32:45 PM EDT, Chuck Harris cfharris@...
> [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
>
>
> Go fast enough, or small enough, and everything becomes discrete.
>
> That should light a fire!
>
> For example, if you take a standard electron beam, ala a CRT, and sweep the beam
> quickly enough, you can get to a speed where the electron beam looks similar to
> what you would have with a rapid fire BB gun.. Each electron represented by a BB.
> The electrons will land in discrete spots on the screen. The 7104, with its MCP,
> operates in this region.
>
>
>
>
>
>
|
Re: Analog vs Digital Oscilloscopes
Indeed, and that is the slow set of plates. Think
vertical for the real speed.
-Chuck Harris
David DiGiacomo telists@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
On Thu, Jul 20, 2017 at 6:17 PM, Daniel Koller kaboomdk@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
Fastest sweep on a 7104/7B10 is 200pS per division, x10 setting, so 20pS per division. It's actually 2ns/div unmagnified, or 200ps/div magnified.
------------------------------------
Posted by: David DiGiacomo <telists@...>
------------------------------------
|
Re: Analog vs Digital Oscilloscopes
Hi Dan,
I think there is a math error, but its only physics, so
close is pretty good.
That is why I said "The 7104... operates in this region".
Imagine what would have come next if tektronix had made
the next generation leap with the MCP.
The horizontal sweep is not even close to the fastest thing
the 7104 does with its beam... sweep is a pretty slow function
for any scope...
For example, the 7104 travels the beam about 8 divisions in
300ps in the vertical direction, while sweeping 200ps/division
in the horizontal direction... the diagonal speed is pretty
spritely.
And, there is an OEM version of the 7104 that is 3x that
fast. All these speeds are limited by the amplifiers, not
the CRT... The CRT is about another 2x that fast.
Additionally, just because an electron in the beam is launched,
doesn't mean it gets multiplied in the MCP...its only those that
happen to hit an active spot on the MCP's walls at just the
right angle that get multiplied.
Interesting to think about... don't you think?
As to the question about speckle, yep, there is a grainy
character to all of the cells that show on the screen. If
you adjust the internal "MCP Output" pot, you can make the
screen scintillate quite nicely. Go the other direction,
and you can make the beam only show the very hottest electrons
that went down the pipe, making the trace very grainy.
If the 7104 wasn't so rare, it would make quite a nice little
physics experiment.
-Chuck Harris
Daniel Koller kaboomdk@... [hp_agilent_equipment] wrote:
toggle quoted message
Show quoted text
Hi Chuck, Almost, but not quite. I don't know what the electron beam current of a
7104 CRT is. Let's assume 1 microamp (that's probably a low estimate), so 6.24E18
electrons per Coulomb x 1E-6 C/ s = 6.24E12 electrons per second. Fastest
sweep on a 7104/7B10 is 200pS per division, x10 setting, so 20pS per division.
6.24E12 Electrons per sec x 20E-12 = 125 electrons per division..... Wow, you are
right. It would be hard to resolve on a regular CRT and the MCP bins them and
multiplies them of course, but it's almost discrete. However, the uncertainty
principle will make sure that we can't predict when they leave the electron gun
thus blurring any spots on the screen... Is there speckle on the the MCP CRTs?
Dan
On Thursday, July 20, 2017, 4:32:45 PM EDT, Chuck Harris cfharris@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
Go fast enough, or small enough, and everything becomes discrete.
That should light a fire!
For example, if you take a standard electron beam, ala a CRT, and sweep the beam
quickly enough, you can get to a speed where the electron beam looks similar to
what you would have with a rapid fire BB gun.. Each electron represented by a BB.
The electrons will land in discrete spots on the screen. The 7104, with its MCP,
operates in this region.
|
Hi Gerry
Option 010 is the tracking generator and the LO port is part of it. 8591A's with option 010 do appear from time to time, albeit at a price. A quick way of determining of option 010 is fitted is to look for the second N connector under the display.
73 George G6HIG
________________________________________
From: hp_agilent_equipment@... <hp_agilent_equipment@...> on behalf of gerrykav@... [hp_agilent_equipment] <hp_agilent_equipment@...>
Sent: 21 July 2017 09:04
To: hp_agilent_equipment@...
Subject: [hp_agilent_equipment] LO port on HP 8591A
I am about to buy a HP 8591A SA for what seems like a good price, given availability of these units in Ireland (€400). However, it does not have the TG fitted, and when I look at the back, the LO port is blanked off. Is it usual that there is no LO port? There is no option listing this as a feature. I was planning to either build a TG myself or get a generic one, at least in the short-term.
Can anyone illuminate?
Thanks
Gerry
|
Help needed with HP Pin diode.
?I have a Schlumberger 4002 signal generator, I need help with a pin diode in this unit. The pin diode is QPND 4709?(HP manuafacture), I can't find it anywhere, I am looking for this or a replacement for it, would like a non smd, since layout is for leaded axial type. I have no experience with pin diodes and need help. The pin diodes is used for AM modulation and level adjustment of the carrier, please see the schematic I attached.? Thank you. Rgds Henrik
?
|
I am about to buy a HP 8591A SA for what seems like a good price, given availability of these units in Ireland (€400). However, it does not have the TG fitted, and when I look at the back, the LO port is blanked off. Is it usual that there is no LO port? There is no option listing this as a feature. I was planning to either build a TG myself or get a generic one, at least in the short-term.? Can anyone illuminate? Thanks Gerry
|
Re: 141T reference replacement..a cure??
Examination of the 8552A schematics suggests that the blown fuse is connected with +100V only indirectly, because it is the reference controlling the -12.6V regulator.? The +20V rail won't?go above nominal on +100 overvoltage, but there is a 24V/14V crowbar on the -12.6V rail.? The fact that this crowbar is explicitly designed to pass a -24V spike for a few milliseconds after power-on indicates that HP was aware of the gas tube ignition problem.? But if the spike goes on too long, the crowbar setpoint drops to -14V, and poof.
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David C. Partridge