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Re: SCPI Command Parser Firmware For Instrument

 

You might find this helpful:



MK
SCPI Command Parser Firmware For Instrument

 

Anyone here developed a SCPI command parser for embedding in an instrument?? Or know of one well developed.?
?
I have googled and never found a parser that appears to be very compliant to the specification.
?
A simple use case might be to have an Arduino UNO analogread() result available through the USB COM port where the UNO appears to be a SCPI instrument.
?
Regards,
(Forrest) Lee Erickson
Locked Re: Non technical question about the coating on a HP 400E

 

This really is off topic, and now some of the post are getting silly - I have just rejected one from a user that was moderated.?

I would expect anyone reading this list to be aware of the HP/Agilent/Keysight list. The original post would have been far more appropriate there.

The topic is now locked.?
Locked Re: Non technical question about the coating on a HP 400E

 

All of the above mentioned techniques will work.? I'm not sure if the coating on the HP equipment is vinyl or some variation, but if so you can also use a vinyl conditioner for car dashboards.? However the stickiness may be due to a chemical breakdown of the plasticizers in the coating.? If that is the case it will never stop and will eventually come back.? As Leon mentioned about his Nikon camera, this was typical on the "rubber" friction grip strips of many cameras, and on other types of electronic equipment.? Once the breakdown starts I don't think there is any way to stop it.? It will just carry on until the coating disintegrates over time.? That's why for some cameras you can now buy replacement grips as this is the only solution in the long run.? Tobacco smoke is a real witches brew of organic compounds which might have something to do with causing the stickiness if it is attacking the plasticizers in the coating.? Of course the sooner you get it off the better, but the damage may already be done.? I just checked a couple of my HP instruments that I treated with vinyl conditioner a few years ago and they still seem to be OK, but only time will tell.? They came from our local university where smoking was not allowed in the labs at any point in time, so that might be their saving grace.

Cheers,
?John
Re: Open Source Signature Analyzer

 

On 6/30/23 20:04, saipan59 (Pete) wrote:
Yes, S.A. today is only useful in extremely rare cases. For working on older equipment, you need the known-good signatures, and the ability to create the necessary conditions. With newer equipment, BIST and Diagnostics will give a lot more info, and the speeds will be too high for a simple S.A. implementation.
So, even with your early experience using SA in a test bed, you think the speeds are a killer to this approach?
What if Harvey puts it in CPLDs, would that go fast enough?

To me, having SA available on a current design with chip radios could be good. You could trigger a startup of some of the code, then do SA on bitstreams going to the radio and maybe even coming from it -- if you had the right trigger on the start of an external radio signal being received...


--
John Griessen
Locked Re: Non technical question about the coating on a HP 400E

 

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I know that he had retired but I think it was very cruel
to keep that professor in a closet, even if the building
was air conditioned.
Only joking,
Ken g8beq

On 11/07/2023 15:14, Jeff Green wrote:

Thank you for the Simple Green cleaner! It removed all the stickiness in one pass.

And I'll file the sodium bicarbonate away.?We had a piece of cast iron cookware cleaned with a "soda blaster" at a local automobile restoration company.?It's like sand blasting but totally non destructive. We plan to have a heirloom rocking chair cleaned this way. The base layers of paint are lead based and a member of our SWL club own an antique shop and warned me not to use the chemical strippers because they can damage some woods.

I used to be a chemist and my first thought was tobacco smoke so I checked for nicotine.?Nicotine nitrate is extremely stable and residue will last at least 300 years, they've found significant traces on museum pieces that have been locked away at least that long.

This unit belonged to a professor who recently retired and was kept in a closest in an air conditioned building.

It is amazing to see the build quality of HP test equipment! There is something special about real components ass
assembled by hand and (as a computer programmer I know) 'hunks of silicon we've cast spells upon."
My grandfather served visited Switzerland shortly after WWII and bought a Swiss watch. It has a built in stop watch function. I watched as the jeweler cleaned it. The inside is a mess of micro gears.?

I considered becoming a machinist because college was out of the question for financial reasons. I worked part time?
in a machine shop part time and was amazed at the end product. My wife is an artist, she can take a blank sheet of paper, a common pencil, and turn out an amazing sketch.

I lack that level of creativity. As Clint Eastwood said in a movie, "A man has to know his limitations."
Locked Re: Non technical question about the coating on a HP 400E

 

I have had success using a solution of simple green cleaner to remove the stickiness the develops on the HP textured surface used on various instrument cases.
Ang.:Re: [Test Equipment Design & Construction] Non technical question about the coating on a HP 400E

 

I have done this a couple of times.
First I wash with warm water and soap (sulfo)
Then clear it with alcohol?
When completely dry, I covered it with talcum powder?
Then brushed it away with a soft brush and compressed air. (Gently)

Hans


P? tir., den 11. jul. 2023 klokken 11:02, PAUL NICKALLS via groups.io
<paulnick@...> skrev:
I have had some success on other items with a strong solution of sodium bicarbonate which is readily available for cooking purposes. I apply it with a rag allowing a little time for it to penetrate.? There are usually some surfaces on HP lids that are out of sight and thus good for experimentation. I am not sure about baking powder which has some added acid.

Paul G8AQA

On 11/07/2023 09:07, Leon via groups.io wrote:
Something similar happened to my old Nikon D80 camera. I cleaned it with Iso-Propyl Alcohol (IPA). It removed all the stickeyness.

Leon Heller
Locked Re: Non technical question about the coating on a HP 400E

 

¿ªÔÆÌåÓý

I have had some success on other items with a strong solution of sodium bicarbonate which is readily available for cooking purposes. I apply it with a rag allowing a little time for it to penetrate.? There are usually some surfaces on HP lids that are out of sight and thus good for experimentation. I am not sure about baking powder which has some added acid.

Paul G8AQA

On 11/07/2023 09:07, Leon via groups.io wrote:

Something similar happened to my old Nikon D80 camera. I cleaned it with Iso-Propyl Alcohol (IPA). It removed all the stickeyness.

Leon Heller
Locked Re: Non technical question about the coating on a HP 400E

 

Something similar happened to my old Nikon D80 camera. I cleaned it with Iso-Propyl Alcohol (IPA). It removed all the stickeyness.

Leon Heller
Locked Re: Non technical question about the coating on a HP 400E

 

Back in the late 1970¡¯s I encountered the same tackiness in customer units. Is there any coloration difference or filming on the meter? Smoking in repair facilities was acceptable at that time and units we received from Greece and Turkey were particularly bad. We cleaned those units externally with a strong soap and water solution, then a 92% alcohol wash. All glass surfaces were then cleaned with the original Bonami glass cleaner (alcohol and a glass cleaner spray). If we needed to clean the inside of the instrument, we followed the previous procedure, after the alcohol wash we would blow dry the circuit boards with compressed air or oven dry the boards for an hour or longer.
The alcohol wash would significantly reduce the tackiness if it was due to smoking residue.
Don Bitters
Re: Calibration

 

All resistance ranges are low and the battery was tested good & measures over 9vdc.

According to the calibration procedure, the 37XR- A I have is just barely out of spec.

So it is not a big deal for the stuff I do, I just wanted to make the 37XR-A all it can be and apparently it is.

Thanx for the comments.? We can close this out.

--
-Bob
Re: Has any had any experience with the Renesas ICS511MILF ?

 

There weren't many ways to do it, back then. It was intended for two way radio work, where doing reciprocal calculations was too slow while setting control tones for squelch circuits.

On Sun, Jul 9, 2023 at 4:05?PM Jeff Green <Jeff.L.Green1970@...> wrote:

Wow Heath did it the hard way!

Thanks for the view how it had to be done.

?

I found these designs:

?

Page 125 of

?

Page: 41

?

And

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All are variations on a theme.

?

?

I've breadboarded the last one with a 2N3819 as an input buffer which drives two 2n3819 in a Schmidt trigger. This drives the 4046 perfectly. [I was given a box filled with Fairchild 2n3819s so I plan on using them for every project I have.

I added a 3rd divide by 10 for a X10, X100 and, X1000. The last one has some jitter, the LSD varies a bit even with a very stable input. I'll try tweaking the 4046 timing values to see if that helps.

?

My unit will work down to 10mV at ~0.1Hz.

?

We had a battery operated analog clock (boo hiss, I'm dyslexic) that was dropped. I saved the drive electronics because I thought a 1.5V 1 pulse per second device might come in handy one day. I divided it by 10 and have a ~0.1Hz. It is interesting to put it in the freezer and see the frequency drop to 0.85Hz at 0F

0.1Hz X 1000 = 100Hz.

85Hz / 1000 = 0.86Hz

I thought about adding X10,000 but that'd be sort of ridiculous.

?

This is where one needs a frequency counter that does reciprocals. Measure the time between zero crossings, do the math and presto, you have the actual frequency in seconds.

?

I missed the lower frequency limit of the?Renesas ICS511.

?

I know it will work down to at least 1MHz because a classmate used one to multiply a 1MHz TXCO to 6MHz.

?

?
Re: Calibration

 

If you do not have the user manual it is?
Re: Calibration

 

How low are the readings and just on one scale or all scales? New battery, right?

Just a thought looking back at one of my flukes that had a strange resistance error on the lowest scale.? They used a resistor divider in a SIP package which turned out to have a cold solder joint on one lead.? Once open, the low range was off by a few ohms but worked otherwise. Touching the probes together gave a reading several ohms higher than usual.

A schematic would be very helpful to see how resistance is sensed by the meter. Since the accuracy should always remain very good, it is possible the problem is mechanical with the PCB unless the resistance range was exposed to a high voltage or current.
Re: Has any had any experience with the Renesas ICS511MILF ?

 

The ICS511 is intended for crystals from 5 to 27 MHz, or clock inputs from 2 to 50 MHz.? See the datasheet here:



Some multimeters have a low frequency counter built in.? Does yours?? Do you have an oscilloscope?? You can also measure frequencies with an oscilloscope.
Re: Calibration

 

After some pleading, Chris at Fluke, went above & beyond and was able to send me the full calibration procedure for the 37XR-A.
Ironically, Resistance is the only mode that is not calibratible in any way.
--
-Bob
Re: Calibration

 

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If you do not have the operation manual it is here:


?I cannot find a reference for the calibration/service manual. ?There are several references to companies doing calibration on this instrument.
Don Bitters

Re: Has any had any experience with the Renesas ICS511MILF ?

 

I built one of these IB1103 Heathkit counters in the mid to late '70s. Audio, up to 10KHz could be multiplied by 10X, 100X or 1000X.

Here is the schematic:

On Fri, Jul 7, 2023 at 8:58?PM Ed Breya via <edbreya=[email protected]> wrote:
I had never heard of the ICS511, so looked it up. It could be very useful, but I think it's geared for much higher frequencies (like crystal oscillator multiplying), not audio like you describe. You probably would be better off using all CMOS like 4000 series or 74HC, which both have the classic 4046 PLL that you mentioned.

You can make an input amplifier with a self-biased CMOS inverter string like with 4049 or 74C(or HC)04 "UB" (un-buffered) style, to save power, and skip the JFETs. If the input signal will be big enough, a 74HC14 would be simpler yet. I never use TTL anymore, except for maintenance on old gear. If you go with a 4046 type, I think it has this input buffer function built in already (maybe not the old original 4000 series one, but I'm pretty sure the 4046A, 4046B, and 74HC4046(X) do), so all you'd need is a coupling capacitor and some protection from abuse. So, two CMOS ICs could mostly do it, say a 74HC4046 and a 74HC390.

The HP counter you recalled is likely the 5345A reciprocal counter, based on time difference to frequency readout conversion - about 9-10 digits resolution at almost any frequency, with one second gate time. No waiting around to count millions of actual cycles, it just needs to make an accurate time period measurement (with 500 MHz internal clock, plus interpolation), then calculates frequency. The more cycles available, the more it can average to improve the answer.

Ed

Re: Has any had any experience with the Renesas ICS511MILF ?

 

I had never heard of the ICS511, so looked it up. It could be very useful, but I think it's geared for much higher frequencies (like crystal oscillator multiplying), not audio like you describe. You probably would be better off using all CMOS like 4000 series or 74HC, which both have the classic 4046 PLL that you mentioned.

You can make an input amplifier with a self-biased CMOS inverter string like with 4049 or 74C(or HC)04 "UB" (un-buffered) style, to save power, and skip the JFETs. If the input signal will be big enough, a 74HC14 would be simpler yet. I never use TTL anymore, except for maintenance on old gear. If you go with a 4046 type, I think it has this input buffer function built in already (maybe not the old original 4000 series one, but I'm pretty sure the 4046A, 4046B, and 74HC4046(X) do), so all you'd need is a coupling capacitor and some protection from abuse. So, two CMOS ICs could mostly do it, say a 74HC4046 and a 74HC390.

The HP counter you recalled is likely the 5345A reciprocal counter, based on time difference to frequency readout conversion - about 9-10 digits resolution at almost any frequency, with one second gate time. No waiting around to count millions of actual cycles, it just needs to make an accurate time period measurement (with 500 MHz internal clock, plus interpolation), then calculates frequency. The more cycles available, the more it can average to improve the answer.

Ed

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