Re: Oscilloscopes - analog but with digital capability?
I have a Phillips PM3375 out in the workshop, and I'm using an HP54601A in the radio shack to monitor transmitter RF; with accurate directional couplers, I can calibrate watt meters. Not far away, on a very heavy-duty turntable, sits a 141T with 8552B and 8554B plugins. I don't actually use that very much, mainly to check harmonics.
I was using a Leader 15 MHz analog scope with a cracked graticule (now at our radio club) which served almost as well,at least letting me know if the sound card output has reset itself to 100 percent again, but the digitizer lets me capture peaks and know what I have.
The 141T has an analog storage CRT, writing to a charged grid then flooding the CRT with electrons. It's finicky, and the display is perishable, so my "digital" storage is a digital camera on a tripod. Couldn't afford Polaroid film now even if I had the camera.
Cortland KA5S
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--- In hp_agilent_equipment@..., Chris Wilson <chris@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
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Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 21:34:36 -0500, Harvey White <madyn@...> wrote: On Sun, 30 Dec 2012 19:57:46 -0600, you wrote:
On Sun, 30 Dec 2012 20:03:41 -0500, Harvey White <madyn@...> wrote:
On Sun, 30 Dec 2012 14:40:09 -0800 (PST), you wrote:
Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK. That would be the Tektronix 7D20 (as a combined timebase/dual channel scope) which was intended to run at least in the 760x series. I think he means the Tektronix P7001 which attaches to a 7704A between the display and mainframe:
That's a new one on me. The P7001 is not as common as the 7854 which is the same basic design. I have seen one or two in the past couple of years for sale but would prefer the 7854 if only because it is relatively common. Then there was the magnificent 7854. IMO, this is the BEST lab 'scope ever made. It is still my 'scope of choice.
and I'd like to have one, but that's still out there, somewhere.....
The downfall of both of these units was the relatively slow A/D by modern standards. 10 MHz bandwidth for the 468, and about 70 Mhz bandwidth for the 7D20 (IIRC). The 7D20 uses a CCD based sampler like the 2430 series of DSOs. Yep, and they do mention that the CCD has absolutely no static immunity.
Those CCD sampling DSOs occupy a weird place in history. Since Tektronix had access to 100 MS/sec 8 bit ADCs like those used in the 2232, I am not sure why they used them for as long as they did. My guess is that the CCDs were easier to interleave then the digital side of the fast ADCs. The 2232 is limited to 50 MS/sec in chop mode because of that.
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Re: DIY: Repair of HP 8568B Step Attenuators
All-
O.k., I have an 8568B with a bad attenuator (40dB and below are dead).
My big question is - how do you get access to the attenuator to take it apart and clean/repair? It seems to be really buried under a maze of stuff...
Thanks!
Jim
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At 01:44 PM 12/27/2012, you wrote:
Thanks a lot of this.
I just managed to get a 8568B that attenuator has some problems with the 20dB step.
These instructions encourage me to open the attenuator and clean the pads with isopropyl alcohol. Now it works fine.
I didn't made a testped for it i just cold moved carefully the solenoids and checked with dg8saq vnwa the attenuator pads. I'm not sure is the solenoid stuck or is it actually a contact failure.
The instructions how to disaasemble the attenuator was very accurate and easy to follow.
BR, Jarmo
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Re: Oscilloscopes - analog but with digital capability?
I will admit that there is not a complete and free 2230 service manual available online but ArtekManuals and others have scanned service manuals available inexpensively. Maintenance is made easier since the 2230 shares so many parts with the ubiquitous 2232, 2235A, 2221, and others in that series. The 2232 is easier to use and repair than the 2230 but generally at least twice as expensive. On Mon, 31 Dec 2012 13:20:51 +1100, Yuting Wan <ywan03@...> wrote: I've looked into the Tek 2230 before and found it's performance and ease of use is nowhere near the Fluke PM3390. It's also very hard to get detailed info of 2230. For Fluke PM3390, you can purchase a service manual for very little but some parts are very hard to get. Then you end up getting a few units and start cannibalise them.
On 31/12/2012, at 12:46 PM, David wrote:
Tektronix made a number of oscilloscopes like you describe including some interesting hybrids. Phillips made some oscilloscopes contemporary to the Tektronix 2232 series but supporting 4 channels, 200 MHz bandwidths, and with more features. I have avoided them because of the lack of service information.
Here are the Tektronix analog oscilloscopes that include at least some form of digital storage roughly in order:
The Tektronix P7001 attaches to a 7704A (200 MHz) between the display and mainframe:
The Tektronix 7854 (400 MHz) works like a P7001 but is all one unit. It uses the analog timebase for digital storage which has the side effect of allowing equivalent time sampling without a clock delay timer. With a 7B87 timebase, it also supports low speed real time single shot captures with pretrigger. The user interface and programming make a great companion to your HP RPN calculator.
The Tektronix 468 is a 465 (100 MHz) with a digitizer module (8 bits and 25 MS/sec) mounted on top. It apparently supports some type of equivalent time sampling called "jitter correction" in the manual but is still limited to a 10 MHz bandwidth in storage mode.
The 2232 (100 MHz 100 MS/sec), 2224 (60 MHz and 100 MS/sec), and 2230 (100 MHz 20 MS/sec) support real time sampling, equivalent time sampling, and peak detection. The other 22xx series oscilloscopes operate with real time sampling only and no peak detection. The 2221A (100 MHz 100 MS/sec) and 2221 (100 MHz 20 MS/sec) are single timebase versions of the 2232 and 2230.
My 2230 is my go to oscilloscope although if I need to backup waveforms for later, I use my 2232 instead because my 2230 does not have the memory backup option.
The Tektronix 2252 is a 2247A (100 MHz 4 channels) with limited digital storage using sequential sampling.
Some of the above oscilloscopes have much higher storage resolution than you would expect. The 2252 is 12 bits vertical. The 7854 is 10 bits horizontal and vertical.
Of the above, the 2230 and 2232 are the most common and easiest to maintain. The 2221 and 2221A are just as easy to maintain because they are essentially the same as the 2230 and 2232. The 7854 is the most versatile but lacks real time operation and peak detection.
On Sun, 30 Dec 2012 17:09:00 -0500, Bryce Schroeder <bryce.schroeder@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy.
------------------------------------
Yahoo! Groups Links
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Re: Oscilloscopes - analog but with digital capability?
Back in the mid 80's I remember using the Tek 7D20 digitizer plug-in. It only had a 20MHz sampling rate with an over sampling bandwidth of 70MHz. It was OK for sampling in the audio range but not go at TTL rates.
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--- In hp_agilent_equipment@..., Yuting Wan <ywan03@...> wrote: I've looked into the Tek 2230 before and found it's performance and ease of use is nowhere near the Fluke PM3390. It's also very hard to get detailed info of 2230. For Fluke PM3390, you can purchase a service manual for very little but some parts are very hard to get. Then you end up getting a few units and start cannibalise them.
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Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 19:57:46 -0600, you wrote: On Sun, 30 Dec 2012 20:03:41 -0500, Harvey White <madyn@...> wrote:
On Sun, 30 Dec 2012 14:40:09 -0800 (PST), you wrote:
Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK. That would be the Tektronix 7D20 (as a combined timebase/dual channel scope) which was intended to run at least in the 760x series. I think he means the Tektronix P7001 which attaches to a 7704A between the display and mainframe:
That's a new one on me. Then there was the magnificent 7854. IMO, this is the BEST lab 'scope ever made. It is still my 'scope of choice.
and I'd like to have one, but that's still out there, somewhere.....
The downfall of both of these units was the relatively slow A/D by modern standards. 10 MHz bandwidth for the 468, and about 70 Mhz bandwidth for the 7D20 (IIRC). The 7D20 uses a CCD based sampler like the 2430 series of DSOs.
Yep, and they do mention that the CCD has absolutely no static immunity. Harvey
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Directional bridge in HP 85046A
The A3 Directional Bridge (Port 1) has a pair of toroids on each side. The pair with brown "wire" is wound with coax. Is the grey "wire" on the other pair also coax?
I have an 85046A S parameter test set with identical faults on both directional couplers (I did not believe it either) and looking at the inside of one seems suspicious as the "Bridge" does not appear balanced in construction. Each end of the grey "wire" out of the toroid pair ends in a solder blob. I cannot see if it is/was a coax.
I looked at the coupler on the VNA from input to output after doing a B/R thru calibration and it starts at -20dB and climbs exponentially to -2dB at 1GHz, stays there then drops off a bit at the 3GHz end. I used a Transmission/Reflection Test Set with "Test" feeding the Transfer Switch end and with the Port 1 end on "B" on the 8753B. Coupler port terminated but it does not change anything.
When connected to the 8753B S11 and S22 with the ports open have identical shapes with two humps starting at -70dB rising to -15dB,and separated by a notch going to -55dB around 2GHz. When terminated they both rise exponentially from -70dB to -20dB at around 2GHz then flatten out. (this has nothing to do with the other thread I started, this is a different 85046A)
I have eliminated the splitter, attenuator, and Transfer Switch because I thought it had to be something in common to both Directional Bridges. I am now looking at the A3 as a separate component.
I can send a full description .docx file with pictures if I have an email.
Main question: is the grey "wire" on the toroids a coax?
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Re: Oscilloscopes - analog but with digital capability?
I've looked into the Tek 2230 before and found it's performance and ease of use is nowhere near the Fluke PM3390. It's also very hard to get detailed info of 2230. For Fluke PM3390, you can purchase a service manual for very little but some parts are very hard to get. Then you end up getting a few units and start cannibalise them. On 31/12/2012, at 12:46 PM, David wrote: Tektronix made a number of oscilloscopes like you describe including some interesting hybrids. Phillips made some oscilloscopes contemporary to the Tektronix 2232 series but supporting 4 channels, 200 MHz bandwidths, and with more features. I have avoided them because of the lack of service information.
Here are the Tektronix analog oscilloscopes that include at least some form of digital storage roughly in order:
The Tektronix P7001 attaches to a 7704A (200 MHz) between the display and mainframe:
The Tektronix 7854 (400 MHz) works like a P7001 but is all one unit. It uses the analog timebase for digital storage which has the side effect of allowing equivalent time sampling without a clock delay timer. With a 7B87 timebase, it also supports low speed real time single shot captures with pretrigger. The user interface and programming make a great companion to your HP RPN calculator.
The Tektronix 468 is a 465 (100 MHz) with a digitizer module (8 bits and 25 MS/sec) mounted on top. It apparently supports some type of equivalent time sampling called "jitter correction" in the manual but is still limited to a 10 MHz bandwidth in storage mode.
The 2232 (100 MHz 100 MS/sec), 2224 (60 MHz and 100 MS/sec), and 2230 (100 MHz 20 MS/sec) support real time sampling, equivalent time sampling, and peak detection. The other 22xx series oscilloscopes operate with real time sampling only and no peak detection. The 2221A (100 MHz 100 MS/sec) and 2221 (100 MHz 20 MS/sec) are single timebase versions of the 2232 and 2230.
My 2230 is my go to oscilloscope although if I need to backup waveforms for later, I use my 2232 instead because my 2230 does not have the memory backup option.
The Tektronix 2252 is a 2247A (100 MHz 4 channels) with limited digital storage using sequential sampling.
Some of the above oscilloscopes have much higher storage resolution than you would expect. The 2252 is 12 bits vertical. The 7854 is 10 bits horizontal and vertical.
Of the above, the 2230 and 2232 are the most common and easiest to maintain. The 2221 and 2221A are just as easy to maintain because they are essentially the same as the 2230 and 2232. The 7854 is the most versatile but lacks real time operation and peak detection.
On Sun, 30 Dec 2012 17:09:00 -0500, Bryce Schroeder <bryce.schroeder@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy. [Non-text portions of this message have been removed]
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Re: HP 8970B firmware v2800+ wanted
Hi Vlandan, Thank you for your answer. Do you think version 8005x is compatible with all 8970B's? (including mine: S/N 2721Axxxx) Seems strange that this number is a five-digit where mine has a four-digit version... Christian Le 31 dc. 2012 � 02:48, pianovt a crit : Hi Christian,
I also see a newer version (standard, not Opt 020) there:
)_ROM_Images_and_Drivers/HP_8970B/HP_8970B_08970_8005X.zip
Vladan
--- In hp_agilent_equipment@..., f1gwr <f1gwr@...> wrote: ...
Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B
So I'm looking for 2800 release or later.
Thanks for your help, Christian ... [Non-text portions of this message have been removed]
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Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 20:03:41 -0500, Harvey White <madyn@...> wrote: On Sun, 30 Dec 2012 14:40:09 -0800 (PST), you wrote:
Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK. That would be the Tektronix 7D20 (as a combined timebase/dual channel scope) which was intended to run at least in the 760x series. I think he means the Tektronix P7001 which attaches to a 7704A between the display and mainframe: Then there was the magnificent 7854. IMO, this is the BEST lab 'scope ever made. It is still my 'scope of choice.
and I'd like to have one, but that's still out there, somewhere.....
The downfall of both of these units was the relatively slow A/D by modern standards. 10 MHz bandwidth for the 468, and about 70 Mhz bandwidth for the 7D20 (IIRC).
The 7D20 uses a CCD based sampler like the 2430 series of DSOs.
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Re: Oscilloscopes - analog but with digital capability?
Thanks for all this information. Certainly there are more options to consider than I thought there would be if it existed at all.
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On Sun, Dec 30, 2012 at 8:46 PM, David <davidwhess@...> wrote: Tektronix made a number of oscilloscopes like you describe including some interesting hybrids. Phillips made some oscilloscopes contemporary to the Tektronix 2232 series but supporting 4 channels, 200 MHz bandwidths, and with more features. I have avoided them because of the lack of service information.
Here are the Tektronix analog oscilloscopes that include at least some form of digital storage roughly in order:
The Tektronix P7001 attaches to a 7704A (200 MHz) between the display and mainframe:
The Tektronix 7854 (400 MHz) works like a P7001 but is all one unit. It uses the analog timebase for digital storage which has the side effect of allowing equivalent time sampling without a clock delay timer. With a 7B87 timebase, it also supports low speed real time single shot captures with pretrigger. The user interface and programming make a great companion to your HP RPN calculator.
The Tektronix 468 is a 465 (100 MHz) with a digitizer module (8 bits and 25 MS/sec) mounted on top. It apparently supports some type of equivalent time sampling called "jitter correction" in the manual but is still limited to a 10 MHz bandwidth in storage mode.
The 2232 (100 MHz 100 MS/sec), 2224 (60 MHz and 100 MS/sec), and 2230 (100 MHz 20 MS/sec) support real time sampling, equivalent time sampling, and peak detection. The other 22xx series oscilloscopes operate with real time sampling only and no peak detection. The 2221A (100 MHz 100 MS/sec) and 2221 (100 MHz 20 MS/sec) are single timebase versions of the 2232 and 2230.
My 2230 is my go to oscilloscope although if I need to backup waveforms for later, I use my 2232 instead because my 2230 does not have the memory backup option.
The Tektronix 2252 is a 2247A (100 MHz 4 channels) with limited digital storage using sequential sampling.
Some of the above oscilloscopes have much higher storage resolution than you would expect. The 2252 is 12 bits vertical. The 7854 is 10 bits horizontal and vertical.
Of the above, the 2230 and 2232 are the most common and easiest to maintain. The 2221 and 2221A are just as easy to maintain because they are essentially the same as the 2230 and 2232. The 7854 is the most versatile but lacks real time operation and peak detection.
On Sun, 30 Dec 2012 17:09:00 -0500, Bryce Schroeder <bryce.schroeder@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy. ------------------------------------
Yahoo! Groups Links
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Re: HP 8970B firmware v2800+ wanted
Hi Christian,
I also see a newer version (standard, not Opt 020) there:
)_ROM_Images_and_Drivers/HP_8970B/HP_8970B_08970_8005X.zip
Vladan
toggle quoted message
Show quoted text
--- In hp_agilent_equipment@..., f1gwr <f1gwr@...> wrote: ... Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B
So I'm looking for 2800 release or later.
Thanks for your help, Christian ...
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Re: Oscilloscopes - analog but with digital capability?
Tektronix made a number of oscilloscopes like you describe including some interesting hybrids. Phillips made some oscilloscopes contemporary to the Tektronix 2232 series but supporting 4 channels, 200 MHz bandwidths, and with more features. I have avoided them because of the lack of service information. Here are the Tektronix analog oscilloscopes that include at least some form of digital storage roughly in order: The Tektronix P7001 attaches to a 7704A (200 MHz) between the display and mainframe: The Tektronix 7854 (400 MHz) works like a P7001 but is all one unit. It uses the analog timebase for digital storage which has the side effect of allowing equivalent time sampling without a clock delay timer. With a 7B87 timebase, it also supports low speed real time single shot captures with pretrigger. The user interface and programming make a great companion to your HP RPN calculator. The Tektronix 468 is a 465 (100 MHz) with a digitizer module (8 bits and 25 MS/sec) mounted on top. It apparently supports some type of equivalent time sampling called "jitter correction" in the manual but is still limited to a 10 MHz bandwidth in storage mode. The 2232 (100 MHz 100 MS/sec), 2224 (60 MHz and 100 MS/sec), and 2230 (100 MHz 20 MS/sec) support real time sampling, equivalent time sampling, and peak detection. The other 22xx series oscilloscopes operate with real time sampling only and no peak detection. The 2221A (100 MHz 100 MS/sec) and 2221 (100 MHz 20 MS/sec) are single timebase versions of the 2232 and 2230. My 2230 is my go to oscilloscope although if I need to backup waveforms for later, I use my 2232 instead because my 2230 does not have the memory backup option. The Tektronix 2252 is a 2247A (100 MHz 4 channels) with limited digital storage using sequential sampling. Some of the above oscilloscopes have much higher storage resolution than you would expect. The 2252 is 12 bits vertical. The 7854 is 10 bits horizontal and vertical. Of the above, the 2230 and 2232 are the most common and easiest to maintain. The 2221 and 2221A are just as easy to maintain because they are essentially the same as the 2230 and 2232. The 7854 is the most versatile but lacks real time operation and peak detection. On Sun, 30 Dec 2012 17:09:00 -0500, Bryce Schroeder <bryce.schroeder@...> wrote: Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy.
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Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 14:40:09 -0800 (PST), you wrote: Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK. That would be the Tektronix 7D20 (as a combined timebase/dual channel scope) which was intended to run at least in the 760x series. Then there was the magnificent 7854. IMO, this is the BEST lab 'scope ever made. It is still my 'scope of choice.
and I'd like to have one, but that's still out there, somewhere..... The downfall of both of these units was the relatively slow A/D by modern standards. 10 MHz bandwidth for the 468, and about 70 Mhz bandwidth for the 7D20 (IIRC). There were also some Transient Data Digitizers that used specialized double ended CRTs, I think.
That would be the 7912, IIRC, which used the 7B16P and 7B90P programmable plugins as a minimum. Never had one, but it looks like an interesting possibility to have. Harvey -John
=============
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this.
So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy.
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Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 17:09:00 -0500, you wrote: Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were basically analog scopes, but with the ability to digitize what is seen on the display (at some lesser resolution than what you might be able to see on the actual display, presumably)? As I understand it - which may admittedly be incorrect - some of the older spectrum analyzers are sort of like this. Look at the Tek 468 scope. It had a digital backpack, capable of about 10 Mhz bandwidth. The processor was (IIRC) and 8051 style, with limited memory, etc. The basic scope was a 465, a 100 Mhz dual channel scope. The circuitry was an add-on backpack that could take over the display (without the processor running, the scope won't work). The amount of digital controls available were minimal, but allowed you to measure waveform extensions (amplitude) and timing conditions with several manually adjustable cursors. IIRC there was one memory. A more modern processor would allow much greater capability, and one of these days, I might just make a plugin to make that happen. If you look at the scope, there's a digital backpack with an add-on hood for the display, and an extension with the processor boards. The scope was capable of running the HPIB interface as a talker only. Other scopes, say in the 24xx series for Tektronix, are completely digital. Harvey So, this hypothetical oscilloscope type would basically have the analog display "in parallel" with an ADC, such that you could look at the screen and see the waveform displayed like an analog scope, or use the ADC to see a digital approximation. (Presumably the digital stuff could also be used to capture and store one-shot things like a regular digital oscilloscope.) This would be opposed to a purely digital oscilloscope where the ADC and memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display would be "higher resolution" than the ability of the ADC, but the digital stuff would enable automation and storage ability. This would stop being important once digital was high-enough resolution to look more or less indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model numbers?
Thanks for your time - sorry if that was a bit lengthy.
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FS: Mint HP 8447D 0.1-1300MHz amplifier
Hi all.
I have a mint HP 8447D 0.1-1300MHz amplifier for sale. It is in full working condition and in good shape. It is excess to my needs and so selling it away.
Asking $250 plus shipping.
Pictures of the item:
.. Erik
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Re: Oscilloscopes - analog but with digital capability?
HP 1980B has a digital sampler board used to store a waveform. It has a whole 501 points of resolution. This is an Analog scope with Digital controls. Very nice " AUTO-SCOPE " for it's age.
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--- In hp_agilent_equipment@..., Bryce Schroeder <bryce.schroeder@...> wrote: Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were SNIP <
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Tom, you may have a valid point. I'll have to look at the schematics. I think it's a bit safer however to use a battery substitution voltage then to have the entire instrument up and running. Heaven forbid something falls..etc.
Thanks,
Jeff
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On 12/30/2012 4:59 PM, Tom Miller wrote:
----- Original Message ----- From: "Jeff Machesky" <jeff@... <mailto:jeff%40codebest.com>> To: <hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>> Sent: Sunday, December 30, 2012 2:31 PM Subject: Re: [hp_agilent_equipment] Re: 3457a on the way
Todd, the battery is already on my list of to do items. The security seal on the meter I've got on the way appears to have not been broken. I assume this is from the last cal back in 98. The fact that it has a seal on the case might be a sign that someone had done work internally, perhaps just the offsets.
I have two options, check the battery and replace as needed when I get the meter or wait until just before sending it off for cal knowing that if I loose the cal data it's not the end of the world. I assume Agilent isn't going to charge more because the cal data was lost? I think either way I need to know what the voltage is of the battery and what type of battery it is. Replacement of course would be done with a current limited power source in place to act as the battery while it's being changed. A bench supply with the voltage matched should do the trick. I'm hoping it will already have the 3.4v battery to make my life a bit easier. Not that I mind replacing a couple resistors.
Thanks,
Jeff
Why not just apply AC power while changing the battery. Just use an ungrounded soldering iron.
Or is there some other thing I am not thinking about?
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----- Original Message ----- From: "Jeff Machesky" <jeff@...> To: <hp_agilent_equipment@...> Sent: Sunday, December 30, 2012 2:31 PM Subject: Re: [hp_agilent_equipment] Re: 3457a on the way Todd, the battery is already on my list of to do items. The security seal on the meter I've got on the way appears to have not been broken. I assume this is from the last cal back in 98. The fact that it has a seal on the case might be a sign that someone had done work internally, perhaps just the offsets.
I have two options, check the battery and replace as needed when I get the meter or wait until just before sending it off for cal knowing that if I loose the cal data it's not the end of the world. I assume Agilent isn't going to charge more because the cal data was lost? I think either way I need to know what the voltage is of the battery and what type of battery it is. Replacement of course would be done with a current limited power source in place to act as the battery while it's being changed. A bench supply with the voltage matched should do the trick. I'm hoping it will already have the 3.4v battery to make my life a bit easier. Not that I mind replacing a couple resistors.
Thanks,
Jeff
Why not just apply AC power while changing the battery. Just use an ungrounded soldering iron. Or is there some other thing I am not thinking about?
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Re: HP 8970B firmware v2800+ wanted
Christian,
I have an 8970B, SN 2947Axxxxx, OPT H18, and when I enter '99.9 Special Function', I get '08844' in the left hand display.
When I enter '47.1 Special Function', I get no errors.
Is this what you need? If so, I can open the unit, read the EPROM's, and send you the data.
Joe
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-----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] On Behalf Of f1gwr Sent: Sunday, December 30, 2012 3:54 PM To: hp_agilent_equipment@... Subject: [hp_agilent_equipment] HP 8970B firmware v2800+ wanted In order to use a HP 8757A SNA as a display, the noise figure meter 8970B
requests version 2800 at least to enable special functions 47.x as described in Product Note 8970B/S-4. My datecode is only 2725 yelding E36 error. Bad luck! To display firmware release enter 99.9 SP on the 8970B. If someone could provide me with related ROM dump, would be great!
Almost two years ago I posted the above message, but till now did not get suitable answer. Maybe someone could read a recent ROM and post it? Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B So I'm looking for 2800 release or later. Thanks for your help, Christian
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