Re: HP instrument measuring ¡°RMS Power¡±
On Sat, 3 Sep 2022 at 07:48, tgerbic < tgerbic@...> wrote:
The 434A is a calorimetric meter. It is calibrated using by measuring a DC power supply and the calibration port on the front provides a DC signal. I suspect it would effectively be RMS since it is the same wattage measurement for AC as DC.
--
T. Gerbic
Central California
The mean AC power provides the same heating as DC. So RMS watts have no practical use, but that doesn¡¯t stop them being used in the wrong places.?
For a sine wave feeding a resistor, the mean power dissipated in the resistor is not the same as the RMS power. I did once work out the maths of it, but can¡¯t recall the difference - if you Google RMS power, I am sure you will find articles showing ?RMS power is a pointless measurement.?
But as I note from both Analog Devices and Minicircuits, even big companies make the error occasionally.? Keysight seem immune - I can¡¯t see any Keysight products that claim to measure RMS power.?? But I have seen the term on some bit of test equipment. I thought it was old HP, but it might have been Marconi.? -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@...Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom
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Replacement OCXO board for 5315B
Hello everyone,
Just as a follow-up for the other topic (1820-2131 for the 5315B counter).
My 5315B came with Option 004, which is the high-stability OCXO. Unfortunately, the Ovenaire 85-50 oscillator had a problem with the heater which stayed cold, so it "worked" and generated a sinewave, but was 30 Hz away from its nominal 10.0000 MHz.
I decided to use another OCXO and got a Bliley NVG47A, for which I designed a PC board which mounts on the original bracket intended for the Ovenaire oscillator (re: attached pictures). No electrical or mechanical changes to the counter are needed.
I have a few bare PC boards which I'd be glad to sell for $1 each plus the price of mailing from France. If anybody is interested, please let me know !
Cheers,
Joel
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Re: Chips for 5315A/B counter: 1820-2131 and 1820-2312
Hi Kevin,
Of course I'm still reading this thread ! Here's my 1820-2131 story.
The 1820-2131 is a Mostek MK3870 microcontroller which includes mask-programmed ROM. This chip was first produced by Mostek, then second-sourced by Motorola (I guess the 3870 series was never a part of Motorola's product line). Of course, this chip is now pure unobtainum.
I got a 5315B counter which needed a new 1820-2131. Fortunately, the mask-programmed 3870 can be replaced with a 38P70 (the "P" stands for "Piggyback") fitted with an external 2716 EPROM. Although not cheap, the 38P70 is still available on Epay. The next missing part is the microcode which I think was never published by HP.
Fortunately, Maurice Smulders had a disassembled version of the code, apparently read from a 1820-2131 chip by Sean Riddle. He was kind enough to send it to this group (re. his message on 08/18/19), so I burned it into a 2716, plugged it in my 5315A and crossed my fingers. With a little additional debugging, I got it to work :
- The 38P70 seems to require higher logic-high levels on inputs pins 38 (Ext/int) and 39 (/Reset). This is easily fixed by soldering two 100K pull-up resistors on the underside of the board.
- The 5315B worked, but upon power-up it displayed error E1. This code means the checksum mechanism in the microcode has detected a problem, which I was finally able to identify. The root cause is that the disassembly process generated incorrect data at address 0x7E8, which was an unused address in the original code. This byte must be changed to 0x2B:
?? ?7e6: b5??????? OUTS $05
?? ?7e7: 1c??????? POP
?? ?7e8: 2b??????? NOP????????? ; This byte corrected by JS on Oct 6, 2019
?? ?7e9: 2b??????? NOP
?? ?7ea: 2b??????? NOP
With the corrected file (and pull-up resistors), the "piggyback version" of the 1820-2131 works perfectly on a 5315B. I also tested it in a 5316A and it works just as great. A copy of the binary file is attached.
Comments welcome !
Cheers,
Joel
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Re: HP instrument measuring ¡°RMS Power¡±
HP has quite a list of power meters starting in the 43x series numbers. I think all or nearly all are peak or average reading.? Most depend on a thermocouple or diode device to do the power measuring.
The 434A is a calorimetric meter. It is calibrated using by measuring a DC power supply and the calibration port on the front provides a DC signal. I suspect it would effectively be RMS since it is the same wattage measurement for AC as DC.
--
T. Gerbic
Central California
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Re: HP instrument measuring ¡°RMS Power¡±
Jeremy,
I don't think I have seen a 3400A with a scale in watts (option C87) can you send a clear photo of the front and the scale.
I also have a 3400A and it is a great meter with a crest factor like my 3456A.
--
T. Gerbic
Central California
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Which Vector network analysis book to buy - help
I intend to purchase either of both of the following books.? I do have an extensive collection of notes and articles but figure I need some good bedtime reading.? The candidate books are:
1) Handbook of Microwave Component measurement with Advanced VNA Techniques - (J.P. Dunsmore)
2) Fundamentals of Vector Network Analysis - (M.Heibel)
I would normally tend toward the HP publication as most of my equipment is HP and any examples would be directly relevant
BUT - I find following comments on the HP book and would like to get some comments from the group - PREFERABLY from people who have looked at both books in some detail.
a) Re the HP book
I bought this book on the recommendation of an Agilent application engineer. The author also works for Agilent.
The book is full of errors, typographical but also conceptual. For example the author mentions that the scattering parameter s11 is the input impedance of the network. Even a junior engineer knows that s11 is the reflection coefficient, whose value is always less or equal to 1 for all passive networks, whereas the input impedance can take arbitrary values as long as the real part is positive.
Furthermore the formula for the input impedance of a transmission line is incorrect, perhaps a trivial typographical error, but a strong indication that the author was copying formulas carelessly from other sources. In general, it shows superficial knowledge of the whole subject.
The book is below par for any solid theoretical issues. In contrast the book "Fundamentals of Vector Network Analysis" by M. Hiebel is of very high quality, explaining theoretical as wel as practical aspects of measurements. This is a publication by the Agilent competitor, the German company Rohde & Schwarz, and may be hard to get in this country.
B) Re the HP Book
I bought the book in an effort to divine a clear understanding of what's going on in a 3-port balun measurement on my VNA. I didn't get all that I'd hoped for. The text doesn't seem to "take you all the way". I felt at times that some of it was more like those teaser technical articles that promise details, but deliver generalities; as if perhaps Mr. Dunsmore was using this to attract consulting gigs, rather than impart useful, complete "how-to" information..
I find NO 1-4 star ratings for the R&S book, but I also find fewer reviews total.
SO What "enlightenment" can the group give me as to which to pick. - is the HP book really that"buggy"?? The S11 error seems to be a bit gross - could it have been a missed edit in an earlier version?
WHAT SAY? ALL ????
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Re: HP instrument measuring ¡°RMS Power¡±
The HP 400EL meter has the top scale linear db from -10 to +2 and label 1mW 600 Ohms
John
toggle quoted message
Show quoted text
On 9/2/2022 5:16 PM, Mikek wrote: What is the option number for that? Should be tag on the back.
It looks like Option 1, is a db scale on the top line.
???????????????????????? Thank, Mikek
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Re: How do you decipher HP serial numbers for date.
With computers it¡¯s easy the first two digits are the year after 1960 and the next two digits the week. ?I¡¯ve heard several different versions for instruments. The most common relates to the date the last changes were locked into the next evolution of the instrument. It is a year/week but I never heard how it was defined.?
I only did 10 years at HP from ¡®77 to ¡®87. Maybe some of the longer, ok older, guys will have better/different stuff
steve
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When I powered up my MMS 22GHz SA this week and was greeted with this error.
When I run the analyzer self test it seems to pass. ?And I can change CF and spans and the error does not seem to appear. ?
Is there anything I should be doing to not make it worse?
Thanks
Dave
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Probably automatic error correction on an HP computer.
Stuart K6YAZ
Los Angeles
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Re: HP instrument measuring ¡°RMS Power¡±
You¡¯re right, it¡¯s Option C87. The option characters are typed on a silver/black Hewlett-Packard option label.?
On Fri, Sep 2, 2022 at 5:16 PM Mikek < amdx@...> wrote: What is the option number for that? Should be tag on the back.
It looks like Option 1, is a db scale on the top line.
???????????????????????? Thank, Mikek
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Re: HP instrument measuring ¡°RMS Power¡±
What is the option number for that? Should be tag on the back.
It looks like Option 1, is a db scale on the top line.
???????????????????????? Thank, Mikek
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Re: How do you decipher HP serial numbers for date.
On Fri, Sep 2, 2022 at 07:47 AM, Jeremy Nichols wrote:
Also note that all of my examples are 1969 ¡°models.¡± I wonder if HP went with your ¡°Possibility A¡± in order to keep the old serial number format for stuff started in 1969??
That's a very interesting observation. These odd week codes may have just been transition confusion. Anyone got week codes higher than 52 outside the '68-9 format transition period?
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Re: HP instrument measuring ¡°RMS Power¡±
My HP-3400A RMS Voltmeter (serial 1218A22958) was given a meter movement calibrated in Volts, dBw, and RMS Watts. Most 3400As do not have this meter movement.? Jeremy/N6WFO
On Fri, Sep 2, 2022 at 4:20 PM Dr. David Kirkby, Kirkby Microwave Ltd < drkirkby@...> wrote: I am fairly certain that I have seen some instrument from HP that had something on the front to indicate a measurement of RMS power. It might have been an audio signal generator or similar. Does anyone know of such an instrument??
I see Minicircuits sell a 6 GHz power meter that they claim measures RMS Power.?
Analog Devices have an article about a 100 MHz to 40 GHz RMS power meter.
Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@...Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge,
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HP instrument measuring ¡°RMS Power¡±
I am fairly certain that I have seen some instrument from HP that had something on the front to indicate a measurement of RMS power. It might have been an audio signal generator or similar. Does anyone know of such an instrument??
I see Minicircuits sell a 6 GHz power meter that they claim measures RMS Power.?
Analog Devices have an article about a 100 MHz to 40 GHz RMS power meter.
-- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@...Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom
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FS: (US) HP 83525A and 83522A RF Plug-ins for 8350A/B Sweep Generator
For sale, two HP plugins for the HP 8350A/B sweep generator. Both units are in working condition. The frequency range is 0.01 to 8.0 GHz for the 83525A, and 0.01 to 2.4 GHz for the 83522A. Details are here:
If interested, contact me off list. Thank you looking.
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Re: Chips for 5315A/B counter: 1820-2131 and 1820-2312
I hope Joel is still watching this thread.
I just got around to testing the 1820-2131 ROM image in my HP8315A meter.
This interesting thing is that it works fine unaltered with a MK38P70-02H (97400R)
piggyback processor. I am wondering exactly which MK38P70 part number Joel
had used that required a change to a checksum word in the ROM?
I look forward to hearing from him.
Kevin KO3Y
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Hi Bruce,
Yes, guess its a desire/price issue... :)
Anybody wanting to try the script, and having issues, let me know.
Regards, Askild
On Fri, Sep 2, 2022 at 10:10 PM Bruce < bruce@...> wrote: Askid -
Thanks.? Yes, I looked over the 437 and noted the lack on numeric?
keys.? I may take you up on the script if I decide to get a 437.? To?
me it looks like the E series are still too expensive.? I'll just keep?
my eyes open and see what pops up.
Cheers!
Bruce
Quoting Askild <megafluffy@...>:
> Hi Bruce,
>
> The 437B is of course only a single channel power meter, so if you want
> dual upgrade from the 438A you will need to go to the E-series.
> I have a 437B, and it suits my needs for a power meter. I also have a 432A,
> a 435B, and almost a 436A (Its missing the A2, A3, A4 and A5 boards. So if
> anybody want to donate, please let me know :)
>
> I made two simple python scripts to read from, and write cal tables to the
> 437B. Much easier to enter the cal table into a text editor, than using the
> arrow keys.
>
> The biggest drawback on the 437B is the lack of number keys. All entries
> are adjusted with arrow keys, But its easier to just set the frequency,
> than figuring out the correct cal factor and enter that.
>
>
> Regards,
> Askild
>
>
> On Fri, Sep 2, 2022 at 8:43 PM Bruce <bruce@...> wrote:
>
>> Dave - Thanks.
>>
>> I didn't think to take a look at the 437 and I did assume that the 438
>> was an upgrade on the 437 - wrong I guess.? I really do like my 438s
>> except for the inconvenience of entering the cal factor each time.
>>
>> Cheers!
>>
>> Bruce
>>
>> Quoting Dave McGuire <mcguire@...>:
>>
>> > On 9/1/22 23:45, Bruce wrote:
>> >> I currently use HP 438 power meters and am considering upgrading.
>> >> Main driver fo upgrade is I'm getting sick of having to enter the
>> >> cal factor for each frequency measurement.? I would like the
>> >> replacement to be a dual channel device.
>> >>
>> >> I know that latter versions of HP power meters permit entering
>> >> correction tables for use with the 848X power sensors.? What would
>> >> the group recommend?
>> >> Some relevant questions:
>> >> 1) How hard is it to tell the PM what frequency entry to use?
>> >> 2) Do any of the PMs accept an analog voltage to determine the
>> >> frequency correction (that would really be fun)
>> >> 3) Any known problems to look out for
>> >
>> >? ?The E4417/E4418 power meters have come down in price, and are very
>> > nice.? They will also use the later series of sensor heads that
>> > store the calibration factors in an EEPROM in the head, which are
>> > read out by the meter and applied.? You can also use the more common
>> > 84xx heads that only have the calibration factors printed on them,
>> > not stored within them, and you enter the table manually into the
>> > meter's NVRAM.? Then you select the measurement frequency and it
>> > will apply the calibration factor automatically, with interpolation.
>> >
>> >? ?The 437B cannot read the calibration factor table from the newer
>> > sensor heads, but you can enter the table via the front panel or
>> > GPIB. It can store ten tables for ten different sensors.
>> >
>> >? ?My main bench instrument now is an E4417A, which I really like.
>> > The display is excellent; in some modes it will display LARGE digits
>> > which you can read across a room.
>> >
>> >? ?For years I used a 437B, which I still have and use occasionally
>> > in another area.? Everyone complains about the display, I don't have
>> > a problem with it myself, I just don't try to use it in the dark.
>> > The design shares many attributes (and possibly components) with the
>> > 5384/5385 frequency counters, 3468/3478 DMMs, etc, so if you have
>> > one of those, you know what the display is like.
>> >
>> >? ?I've not looked it up, but I'm willing to bet the 437B was
>> > designed well after the 438A.? While I think the 438A is a fine
>> > design in nearly all respects, everything about it seems older than
>> > the 437B.? Older display and button styles, less-featureful firmware
>> > (lack of sensor calibration table storage and interpolation) etc.
>> >
>> >? ?I've never seen a feature by which an analog input voltage can set
>> > the correction factor.
>> >
>> >? ?I have every model of HP RF power meter, including the VXI and MSS
>> > models.? If you'd like specific info on behaviors/features/etc on
>> > any of them that aren't covered by the documentation, don't hesitate
>> > to ask.
>> >
>> >? ? ? ? ? ? ? -Dave
>> >
>> > --
>> > Dave McGuire, AK4HZ
>> > New Kensington, PA
>> >
>> >
>> >
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
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Re: How do you decipher HP serial numbers for date.
Don -
That sounds a lot like the 200As that I used at UW in 1962.
Actually wouldn't suprise me if they (UW) still had a few floating around. I also remember a black cased version.
Cheers!
Bruce
Quoting "Don Bitters via groups.io" <donbitters@...>:
toggle quoted message
Show quoted text
I have actually seen a HP 200A model. It was not in a standard case for the slightly later time period (think HP 540A counter) - the type that the 200C was cased in.? It was in a larger case similar to the 200B, but all of the corners were square and the front panel mounting screws were on the face. The entire unit was a uniform medium grey with white or black markings - I cannot remember which.? I might have seen it at one of the factories or at HP Palo Alto, many, many years ago (1970's).
Don Bitters
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Askid -
Thanks. Yes, I looked over the 437 and noted the lack on numeric keys. I may take you up on the script if I decide to get a 437. To me it looks like the E series are still too expensive. I'll just keep my eyes open and see what pops up.
Cheers!
Bruce
Quoting Askild <megafluffy@...>:
toggle quoted message
Show quoted text
Hi Bruce,
The 437B is of course only a single channel power meter, so if you want
dual upgrade from the 438A you will need to go to the E-series.
I have a 437B, and it suits my needs for a power meter. I also have a 432A,
a 435B, and almost a 436A (Its missing the A2, A3, A4 and A5 boards. So if
anybody want to donate, please let me know :)
I made two simple python scripts to read from, and write cal tables to the
437B. Much easier to enter the cal table into a text editor, than using the
arrow keys.
The biggest drawback on the 437B is the lack of number keys. All entries
are adjusted with arrow keys, But its easier to just set the frequency,
than figuring out the correct cal factor and enter that.
Regards,
Askild
On Fri, Sep 2, 2022 at 8:43 PM Bruce <bruce@...> wrote:
Dave - Thanks.
I didn't think to take a look at the 437 and I did assume that the 438
was an upgrade on the 437 - wrong I guess. I really do like my 438s
except for the inconvenience of entering the cal factor each time.
Cheers!
Bruce
Quoting Dave McGuire <mcguire@...>:
On 9/1/22 23:45, Bruce wrote:
I currently use HP 438 power meters and am considering upgrading.
Main driver fo upgrade is I'm getting sick of having to enter the
cal factor for each frequency measurement. I would like the
replacement to be a dual channel device.
I know that latter versions of HP power meters permit entering
correction tables for use with the 848X power sensors. What would
the group recommend?
Some relevant questions:
1) How hard is it to tell the PM what frequency entry to use?
2) Do any of the PMs accept an analog voltage to determine the
frequency correction (that would really be fun)
3) Any known problems to look out for The E4417/E4418 power meters have come down in price, and are very
nice. They will also use the later series of sensor heads that
store the calibration factors in an EEPROM in the head, which are
read out by the meter and applied. You can also use the more common
84xx heads that only have the calibration factors printed on them,
not stored within them, and you enter the table manually into the
meter's NVRAM. Then you select the measurement frequency and it
will apply the calibration factor automatically, with interpolation.
The 437B cannot read the calibration factor table from the newer
sensor heads, but you can enter the table via the front panel or
GPIB. It can store ten tables for ten different sensors.
My main bench instrument now is an E4417A, which I really like.
The display is excellent; in some modes it will display LARGE digits
which you can read across a room.
For years I used a 437B, which I still have and use occasionally
in another area. Everyone complains about the display, I don't have
a problem with it myself, I just don't try to use it in the dark.
The design shares many attributes (and possibly components) with the
5384/5385 frequency counters, 3468/3478 DMMs, etc, so if you have
one of those, you know what the display is like.
I've not looked it up, but I'm willing to bet the 437B was
designed well after the 438A. While I think the 438A is a fine
design in nearly all respects, everything about it seems older than
the 437B. Older display and button styles, less-featureful firmware
(lack of sensor calibration table storage and interpolation) etc.
I've never seen a feature by which an analog input voltage can set
the correction factor.
I have every model of HP RF power meter, including the VXI and MSS
models. If you'd like specific info on behaviors/features/etc on
any of them that aren't covered by the documentation, don't hesitate
to ask.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
|
Dr. David Kirkby, Kirkby Microwave Ltd
Jeremy Nichols