Re: Understanding the 8753ES frequency loop
Be careful "bench testing" Yig Tuned Ocillators" (YIG = Yttrium Iron
Garnet by the way *.)
Older designs that use + and - polarity supplies can be destroyed if you
get the power up sequence wrong, the little FET that "is" the oscillator
dies.? Similar can happen (or at best some damage that makes them
produce less signal power) if they are run without a RF load of some sort.
*
Plus Wikipedia has some good references too.
From past experience working professionally servicing Spectrum Analysers
to component level that used YIG Oscillators,? check the power supply
rails that feed the coil drivers, also any degaussing scheme, if such is
fitted.
A sudden and permanent step change in the current/frequency
relationship, and also a change in the apparent dynamics of the coil
driver (stability issues) can be an indication of shorted turns within
the tuning coil.? If, there are any documented figures for the tuning
coil inductance, that can of course be checked with a LCR bridge, at low
power.
Take care..
Dave B (G0WBX)
--
Created on and sent from a Unix like PC running and using free and open source software:
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What are main differences between the HP8753D and the HP8753ES? I could maybe figure this out from old HP catalogs but if someone on the list knows I would appreciate your insight.
Thanks.
Steve, K8JQ
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Re: Understanding the 8753ES frequency loop
On Thu, Mar 21, 2019 at 01:29 PM, Peter Gottlieb wrote:
Should the FM input be zero?
Yes, the numbers I gave for the main coil are strictly that - FM coil disconnected. Incidentally, the main coil has a resistance of approximately 44 Ohms at room temperature. That will give you a way to calculate the voltage across the coil for a static case. Vladan
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Re: I'm officially lost now with this 8753ES
...who, if they had any influence on file formats and compression
algorithms, indicates a serious problem within the company.
Not an uncommon problem, by any stretch, but a serious one.
-Dave
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Show quoted text
On 3/21/19 4:54 PM, bownes wrote: Yeah, but you have factor in the suits.
On Thu, Mar 21, 2019 at 4:46 PM Dave McGuire <mcguire@...
<mailto:mcguire@...>> wrote:
? Pretty sure the 8753D is newer than that, but even if it isn't, JPG
was *never* suitable for that sort of imaging.? A good choice (perhaps
the only "right" choice) in 1995 would have been GIF.? Heck, even the
awful BMP would've been better than JPG!
? ? ? ? ? ? ?-Dave
On 3/21/19 4:44 PM, W2HX wrote:
> I don't know the age of these VNAs but PNG was only invented in
1995. Probably needed a few more years before they became popular
such that an engineer would consider using it. Maybe that explains it?
> ________________________________________
> From: [email protected]
<mailto:[email protected]>
<[email protected]
<mailto:[email protected]>> on behalf of Dave
McGuire <mcguire@... <mailto:mcguire@...>>
> Sent: Thursday, March 21, 2019 4:36 PM
> To: [email protected]
<mailto:[email protected]>
> Subject: Re: [HP-Agilent-Keysight-equipment] I'm officially lost
now with this 8753ES
>
> On 3/18/19 3:32 PM, pianovt via Groups.Io wrote:
>> Yes, PNG is great for screen shots. The problem with the 8753D/ES
>> graphics is that the firmware guys didn't do the best job. They
added a
>> graphics dump, but they only implemented jpg. To make it worse, you
>> can't download it via GPIB, it has to be stored to a floppy. At
least, I
>> don't see a command to download the JPG via GPIB. If anyone here
knows
>> how, please let me know.
>
>? ?Wow, I can't imagine that any engineer who was able to get hired
by HP
> wouldn't understand why JPG isn't appropriate for screen shots or
other
> line art. (or anything else that isn't a continuous-tone natural
scene,
> which is what JPG was designed for, and the only thing for which it
> works well)
>
>? ? ? ? ? ? ? -Dave
>
> --
> Dave McGuire, AK4HZ
> New Kensington, PA
>
>
>
>
>
>
--
Dave McGuire, AK4HZ
New Kensington, PA
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: I'm officially lost now with this 8753ES
Yeah, but you have factor in the suits.
On Thu, Mar 21, 2019 at 4:46 PM Dave McGuire < mcguire@...> wrote:
? Pretty sure the 8753D is newer than that, but even if it isn't, JPG
was *never* suitable for that sort of imaging.? A good choice (perhaps
the only "right" choice) in 1995 would have been GIF.? Heck, even the
awful BMP would've been better than JPG!
? ? ? ? ? ? ?-Dave
On 3/21/19 4:44 PM, W2HX wrote:
> I don't know the age of these VNAs but PNG was only invented in 1995. Probably needed a few more years before they became popular such that an engineer would consider using it. Maybe that explains it?
> ________________________________________
> From: [email protected] <[email protected]> on behalf of Dave McGuire <mcguire@...>
> Sent: Thursday, March 21, 2019 4:36 PM
> To: [email protected]
> Subject: Re: [HP-Agilent-Keysight-equipment] I'm officially lost now with this 8753ES
>
> On 3/18/19 3:32 PM, pianovt via Groups.Io wrote:
>> Yes, PNG is great for screen shots. The problem with the 8753D/ES
>> graphics is that the firmware guys didn't do the best job. They added a
>> graphics dump, but they only implemented jpg. To make it worse, you
>> can't download it via GPIB, it has to be stored to a floppy. At least, I
>> don't see a command to download the JPG via GPIB. If anyone here knows
>> how, please let me know.
>
>? ?Wow, I can't imagine that any engineer who was able to get hired by HP
> wouldn't understand why JPG isn't appropriate for screen shots or other
> line art. (or anything else that isn't a continuous-tone natural scene,
> which is what JPG was designed for, and the only thing for which it
> works well)
>
>? ? ? ? ? ? ? -Dave
>
> --
> Dave McGuire, AK4HZ
> New Kensington, PA
>
>
>
>
>
>
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B
I have a mess of these I got new a few?years ago when I repaired some 2075 eatons.? ?Might still have some around.?
Pete wa2odo
On Thu, Mar 21, 2019, 4:47 PM Reginald Beardsley via Groups.Io <pulaskite= [email protected]> wrote: Battery life on the early Dallas parts was 5-7 years.? I had to replace one in a 5-6 year old Sun workstation.? Dallas stopped making them and for a while Maxim made them.? At present the only NVRAM source appears to be ST Microelectronics.
I am waiting for a pair of chips to arrive from the UK as there is no stock in NA.? They are backordered until June.? I was able to get a pair for my Tek 11801 courtesy of a member of the TekScopes list.? RS sold out 34 chips in 8-10 days while I was waiting for my 11801 to arrive.? I got the last two.
The only demand for these is repairing old instruments, so ST appears to make a small run once a year.? The current ST chips use a lithium cell, so shelf life should be reasonably good.? But the cells are very low capacity (40-120 mAh) and can easily be drained if inserted into conductive foam. They are widely available on eBay, but the freshest I could find were US NOS parts of 2002 manufacture.
Reg
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Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B
Battery life on the early Dallas parts was 5-7 years. I had to replace one in a 5-6 year old Sun workstation. Dallas stopped making them and for a while Maxim made them. At present the only NVRAM source appears to be ST Microelectronics.
I am waiting for a pair of chips to arrive from the UK as there is no stock in NA. They are backordered until June. I was able to get a pair for my Tek 11801 courtesy of a member of the TekScopes list. RS sold out 34 chips in 8-10 days while I was waiting for my 11801 to arrive. I got the last two.
The only demand for these is repairing old instruments, so ST appears to make a small run once a year. The current ST chips use a lithium cell, so shelf life should be reasonably good. But the cells are very low capacity (40-120 mAh) and can easily be drained if inserted into conductive foam. They are widely available on eBay, but the freshest I could find were US NOS parts of 2002 manufacture.
Reg
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Re: I'm officially lost now with this 8753ES
I was thinking along the same lines. Barely even heard of PNG initially, it might have been considered risky to use a format which might have died out.
Peter
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Show quoted text
On Mar 21, 2019, at 4:44 PM, W2HX <w2hx@...> wrote:
I don't know the age of these VNAs but PNG was only invented in 1995. Probably needed a few more years before they became popular such that an engineer would consider using it. Maybe that explains it?
________________________________________
From: [email protected] <[email protected]> on behalf of Dave McGuire <mcguire@...>
Sent: Thursday, March 21, 2019 4:36 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] I'm officially lost now with this 8753ES
On 3/18/19 3:32 PM, pianovt via Groups.Io wrote:
Yes, PNG is great for screen shots. The problem with the 8753D/ES
graphics is that the firmware guys didn't do the best job. They added a
graphics dump, but they only implemented jpg. To make it worse, you
can't download it via GPIB, it has to be stored to a floppy. At least, I
don't see a command to download the JPG via GPIB. If anyone here knows
how, please let me know. Wow, I can't imagine that any engineer who was able to get hired by HP
wouldn't understand why JPG isn't appropriate for screen shots or other
line art. (or anything else that isn't a continuous-tone natural scene,
which is what JPG was designed for, and the only thing for which it
works well)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: I'm officially lost now with this 8753ES
Pretty sure the 8753D is newer than that, but even if it isn't, JPG
was *never* suitable for that sort of imaging. A good choice (perhaps
the only "right" choice) in 1995 would have been GIF. Heck, even the
awful BMP would've been better than JPG!
-Dave
toggle quoted message
Show quoted text
On 3/21/19 4:44 PM, W2HX wrote: I don't know the age of these VNAs but PNG was only invented in 1995. Probably needed a few more years before they became popular such that an engineer would consider using it. Maybe that explains it?
________________________________________
From: [email protected] <[email protected]> on behalf of Dave McGuire <mcguire@...>
Sent: Thursday, March 21, 2019 4:36 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] I'm officially lost now with this 8753ES
On 3/18/19 3:32 PM, pianovt via Groups.Io wrote:
Yes, PNG is great for screen shots. The problem with the 8753D/ES
graphics is that the firmware guys didn't do the best job. They added a
graphics dump, but they only implemented jpg. To make it worse, you
can't download it via GPIB, it has to be stored to a floppy. At least, I
don't see a command to download the JPG via GPIB. If anyone here knows
how, please let me know. Wow, I can't imagine that any engineer who was able to get hired by HP
wouldn't understand why JPG isn't appropriate for screen shots or other
line art. (or anything else that isn't a continuous-tone natural scene,
which is what JPG was designed for, and the only thing for which it
works well)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Re: I'm officially lost now with this 8753ES
I don't know the age of these VNAs but PNG was only invented in 1995. Probably needed a few more years before they became popular such that an engineer would consider using it. Maybe that explains it? ________________________________________ From: [email protected] < [email protected]> on behalf of Dave McGuire <mcguire@...> Sent: Thursday, March 21, 2019 4:36 PM To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] I'm officially lost now with this 8753ES On 3/18/19 3:32 PM, pianovt via Groups.Io wrote: Yes, PNG is great for screen shots. The problem with the 8753D/ES
graphics is that the firmware guys didn't do the best job. They added a
graphics dump, but they only implemented jpg. To make it worse, you
can't download it via GPIB, it has to be stored to a floppy. At least, I
don't see a command to download the JPG via GPIB. If anyone here knows
how, please let me know. Wow, I can't imagine that any engineer who was able to get hired by HP wouldn't understand why JPG isn't appropriate for screen shots or other line art. (or anything else that isn't a continuous-tone natural scene, which is what JPG was designed for, and the only thing for which it works well) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
|
Re: Understanding the 8753ES frequency loop
This is beginning to line up.?
3.5 volts at 300 kHz, 3.5 volts across a 40 ohm resistor = 87.5 mA, 87.5 mA divided by 23 mA/GHz = 3.804 GHz, Right in the correct 1-6 MHz high stated range.?
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On Mar 21, 2019, at 4:17 PM, pianovt via Groups.Io < pianovt@...> wrote: It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.
Vladan
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Re: I'm officially lost now with this 8753ES
On 3/18/19 3:32 PM, pianovt via Groups.Io wrote: Yes, PNG is great for screen shots. The problem with the 8753D/ES
graphics is that the firmware guys didn't do the best job. They added a
graphics dump, but they only implemented jpg. To make it worse, you
can't download it via GPIB, it has to be stored to a floppy. At least, I
don't see a command to download the JPG via GPIB. If anyone here knows
how, please let me know. Wow, I can't imagine that any engineer who was able to get hired by HP wouldn't understand why JPG isn't appropriate for screen shots or other line art. (or anything else that isn't a continuous-tone natural scene, which is what JPG was designed for, and the only thing for which it works well) -Dave -- Dave McGuire, AK4HZ New Kensington, PA
|
Re: Understanding the 8753ES frequency loop
Ah, so it starts at zero mA, although we are not interested (and likely not specced)below 3.8 GHz. 3.8 GHz output would then correspond to 3.8 * 23 mA on the main coil. Should the FM input be zero? ?I haven¡¯t yet checked that. I wonder how far the FM input can move it if for example one if those transistors are bad.?
This would be an easy bench test of the YTO, or even easier in-instrument.?
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Show quoted text
On Mar 21, 2019, at 4:17 PM, pianovt via Groups.Io < pianovt@...> wrote: It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.
Vladan
|
Re: Understanding the 8753ES frequency loop
It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.
Vladan
|
Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B
You are thinking of the Dallas SmartSocket series, and it has
no identifying marks on it. It was used with a normal low power
CMOS RAM chip.
The OP's wording was somewhat awkward, but he doesn't have a
smart socket.
The OP has already said that his is an encapsulated Dallas NVRAM
that is installed in a socket.
He is safe to remove it, and read it with his EPROM programmer.
It will read just like a 6116, RAM chip. Different programmers
have different ways of reading the Dallas chip.
-Chuck Harris
Alan Melia via Groups.Io wrote:
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Show quoted text
Maybe not!! some of these Dallas devices have a battery in the socket to maintain the
contents. It may not be one of those but do check before removing anything. The
"socket" may actually be a header and the whole thing unplugged and read in a
programmer as if it was an EPROM. I last came across these in the 1990s using
prototyping/development kits. Others are rather "fat" 28-pin (0.6in.) IC shapes and
have an internal battery I think.
Alan
G3NYK
|
Looking to connect with other 4396B owners
This is my first post to the group, so hello everyone.? You've been a great resource when I've needed to search for information on prospective or actual TE purchases; thanks :)
I recently acquired an Agilent 4396B spectrum/network/impedance analyzer with all of the options (1D5 oven, 1D6 time-gated measurements, 010 impedance measurement) in non-working condition.? The main problem was some stressed SMD electrolytics on the A50 DC-DC converter board, as discussed in service bulletin 11.? There is also something odd in the source assembly, but it seems to be after the ALC power detector; current theory is the semi-rigid coax link from the output attenuator to the bulkhead N connector, or perhaps the N connector itself.? I'm documenting the repair here:
Looking ahead I have a few questions (and will undoubtedly have more as I dig into the analyzer's capabilities):
1) The calibration constants are stored in an EEPROM and updated over GPIB, but as far as I can tell the actual commands and format of the data are not documented.? The only approved way to update the calibration is to use an HP-UX program called "ADJ4396B" running on an ancient HP controller.? Is this likely to be a problem in the long run?? Should I consider sending the instrument out for calibration (assuming the cal lab even has access to this magic software)?? This is for home / hobby use only, so it likely doesn't matter, but I wonder if a window of opportunity is closing as these units get older and the last support is dropped.
2) Has anyone actually laid eyes (or camera) on the insides of the 43961A impedance test fixture?? I have no need for it except curiosity, but it would be fun to leverage the 010 software in my unit.? It could probably be a worthwhile learning experience to build something equivalent at lower frequencies.
3) Not a 4396B question per se, but what is the currently recommended GPIB interface solution in 2019?? I would prefer not to use any NI stuff or the VISA library, but if that's the price for being able to run useful third-party software (like KE5FX's phase-noise tool), I will.? Although in that case I would still prefer options which *can* work with the VISA library but can also work without them.? Cross-platform compatibility with Linux and Windows would be a plus.
Regards,
Mark
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Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B
Maybe not!! some of these Dallas devices have a battery in the socket to maintain the contents. It may not be one of those but do check before removing anything. The "socket" may actually be a header and the whole thing unplugged and read in a programmer as if it was an EPROM. I last came across these in the 1990s using prototyping/development kits. Others are rather "fat" 28-pin (0.6in.) IC shapes and have an internal battery I think.
Alan
G3NYK
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NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B
Hello, I am doing maintenance on my instruments in my lab at the moment and I have a 6811B which poses a problem for me: the calibration constants are stored in a NVRAM whose date code is 1998, the device works well but no doubt it would be advisable to change this circuit without losing the data before the problems occur. We are talking here about the Dallas DS1230Y (28-Pin Encapsulated Package), the integrated circuit is mounted on a socket. ? I have a programmer Xeltek EPROM super pro Model 3000U available, and has in its library the DS1230Y. I am not familiar with this kind of circuit, but from my understanding, I would have to carefully remove the DS1230Y from its socket and make a copy on my EPROM program. ? Is it a good idea to try to do this, or there is a better solution? Normally the DS1230Y should keep its data since there is an integrated battery. ? Yves
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Re: Understanding the 8753ES frequency loop
Thank you.?
Is there a reference point and current?
Another words, X.XXX GHz at XXX.X mA?
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On Mar 21, 2019, at 2:29 PM, pianovt via Groups.Io < pianovt@...> wrote: Hi Peter,
You did a YTO swap, but it didn¡¯t help, right? I guess, unless you know that your spare YTO is good, the result may not be conclusive. Here is some additional YTO information for you:
The main coil sensitivity is 23 mA/GHz? (+/- 1 mA/GHz). At lower frequencies (3.8 to 5+ GHz), the YTO is pretty linear. If you draw a straight line between 3.8 and 5.5 GHz, the deviation should be less than 3MHz, if that. The FM coil sensitivity is around 230kHz/mA. Maximum allowed FM coil current is 150mA.
Vladan
|
Re: Understanding the 8753ES frequency loop
Hi Peter,
You did a YTO swap, but it didn¡¯t help, right? I guess, unless you know that your spare YTO is good, the result may not be conclusive. Here is some additional YTO information for you:
The main coil sensitivity is 23 mA/GHz? (+/- 1 mA/GHz). At lower frequencies (3.8 to 5+ GHz), the YTO is pretty linear. If you draw a straight line between 3.8 and 5.5 GHz, the deviation should be less than 3MHz, if that. The FM coil sensitivity is around 230kHz/mA. Maximum allowed FM coil current is 150mA.
Vladan
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Dave McGuire
bownes