I had one fail in 20 years or so. You have to ensure the window is 100% blocked to UV light (i.e. with a metallic label if you can find one).
Well. the point is different.
The "instrument" becomes smaller and you place it close to your UUT.
Then you can connect to it via the network... which is the whole point of it. You place the interface where you gonna use it and the data acquisition/drive where the UUT sits. The good old days of having the computer next to the racks of instruments is gone... even if you got to the lab, those computers are already on a bench, on a network, and the engineers are not on the rack anymore.
(Exception noted below).
Back in '95 we started to migrate to network connected labs for software development, slowly we started to see physical instruments also become remote.
Today, the exceptions I see, usually by analog/RF hardware guys who are in their bench and have a few instruments with them, everything is remote. The digital hardware guys are doing it in RTL anyhow, with emulators and FGPAs, which are remote access.
Also you got DoD "secured" labs were Intranet access is via secured networks and also ESD controlled labs where you might want to place your engineers in the cold comfort of 69F. Example, working in a bunny suit in a clean room. Usually, you go in there..
This also makes far easier to share a lab, even across continents.
Besides, again with few exceptions, everybody has a networked computer ( laptop ) at their desk. So, a nice touchscreen become the interface for all instruments.
The "instrument" becomes smaller and you place it close to your UUT.
Then you can connect to it via the network... which is the whole point of it. You place the interface where you gonna use it and the data acquisition/drive where the UUT sits. The good old days of having the computer next to the racks of instruments is gone... even if you got to the lab, those computers are already on a bench, on a network, and the engineers are not on the rack anymore.
(Exception noted below).
Back in '95 we started to migrate to network connected labs for software development, slowly we started to see physical instruments also become remote.
Today, the exceptions I see, usually by analog/RF hardware guys who are in their bench and have a few instruments with them, everything is remote. The digital hardware guys are doing it in RTL anyhow, with emulators and FGPAs, which are remote access.
Also you got DoD "secured" labs were Intranet access is via secured networks and also ESD controlled labs where you might want to place your engineers in the cold comfort of 69F. Example, working in a bunny suit in a clean room. Usually, you go in there..
This also makes far easier to share a lab, even across continents.
Besides, again with few exceptions, everybody has a networked computer ( laptop ) at their desk. So, a nice touchscreen become the interface for all instruments.
Do the EEPROM get refreshed when it's powered on?
NAND does. It has a controller that takes care of it.
To make sure NAND lasts a long time, wrap it tightly in foil and then plastic and put it in the freezer. That prevents heat and enthropy.
If you're doing research, yes. That may be true. If your hands are on equipment troubleshooting or sorting out an issue with a design, no it is not true. You are on the bench with the test equipment and computer. If the equipment is ATE, then yes. More of a QC use then.
I remember my audio analyser being "stuff" mounted on a computer chassis (HP 35665A), then more followed. Personally, for low noise work it isn't a workable trend. Computers are typically noise monsters inside. Then there is conducted electrical noise through the USB, Ethernet is isolated.
All I know is that equipment built on a computer, or controlled only by computer introduces all the computer problems we know and love. That includes security. No more high security memory wipe for your test equipment. Now you have any network connected device being a security risk.
Computer control is convenient, and I use it on the bench. However, anything solely controlled by computer will be dead after Microsoft decides to end support for software written for whatever version of Windows was out then. Then my favorite, issues due to Microsoft updates. I vastly prefer Linux but not all test equipment has apps that run on Linux or WINE.
When I'm on my bench, I am not in the mood to waste time troubleshooting Windows issues - because that computer (is mine) a tool I use. You can't waste time fighting your tools.
I remember my audio analyser being "stuff" mounted on a computer chassis (HP 35665A), then more followed. Personally, for low noise work it isn't a workable trend. Computers are typically noise monsters inside. Then there is conducted electrical noise through the USB, Ethernet is isolated.
All I know is that equipment built on a computer, or controlled only by computer introduces all the computer problems we know and love. That includes security. No more high security memory wipe for your test equipment. Now you have any network connected device being a security risk.
Computer control is convenient, and I use it on the bench. However, anything solely controlled by computer will be dead after Microsoft decides to end support for software written for whatever version of Windows was out then. Then my favorite, issues due to Microsoft updates. I vastly prefer Linux but not all test equipment has apps that run on Linux or WINE.
When I'm on my bench, I am not in the mood to waste time troubleshooting Windows issues - because that computer (is mine) a tool I use. You can't waste time fighting your tools.
Hi TonyEE,
No, no refresh on most EEPROMs (never heard of this before), and EPROMS can't be refreshed at all, just rewritten completely after erasure.
No, no refresh on most EEPROMs (never heard of this before), and EPROMS can't be refreshed at all, just rewritten completely after erasure.
Way off topic. But is not possible to program a uv eprom in ckt? Now it depends on what type and if the hardware is capable and designed to change vdd/vpp voltage to enter program mode. Program mode is different going through the 27xx series. EPROMs are floating gates, so reprogramming re-charges the floating gates. You do not have to erase before reprogramming? Obviously have to erase if your changing the data but if you are not, is it not just a refresh? you need to have the image stored in ram or other non-volatile memory since you can’t just program one cell at a time. It’s been a while and going off memory without looking at the datasheets.
I haven't had to deal with an EPROM in over 50 years. I was a digital guy in the late 70's, but now am pretty much an analog engineer.
Hi Rick,
Not once have I seen the host circuit capable of programming an EPROM. Imagine what you could do? Trash the product with a tamper wire or switch for example. May as well just reverse power to the chip, easier. it would also add a lot of cost to the product.
You can reprogram without erasure (freshen it up), but I always used to check the chip after an erase cycle. If it is an old chip failing, you would really want to replace it. It also added a measure of security since chip programmers back then were expensive. Mine cost over $500 each and I bought two (killed by Microsoft changing Windows, it still works fine).
Not once have I seen the host circuit capable of programming an EPROM. Imagine what you could do? Trash the product with a tamper wire or switch for example. May as well just reverse power to the chip, easier. it would also add a lot of cost to the product.
You can reprogram without erasure (freshen it up), but I always used to check the chip after an erase cycle. If it is an old chip failing, you would really want to replace it. It also added a measure of security since chip programmers back then were expensive. Mine cost over $500 each and I bought two (killed by Microsoft changing Windows, it still works fine).
EPROM programmers (and erasers) were a common thing on the scene 50 years ago, kinda thin on the ground these days.
I just checked on Ebay, and they're still around. There are some options that have you load in data byte-by-byte with an array of front panel switches. What would be handy would be an option that worked via USB. Those seem also available, though they are probably not compatible with the voltage levels need to burn UV-erasable EPROMs.
I just checked on Ebay, and they're still around. There are some options that have you load in data byte-by-byte with an array of front panel switches. What would be handy would be an option that worked via USB. Those seem also available, though they are probably not compatible with the voltage levels need to burn UV-erasable EPROMs.
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Mostly for service and repair. EEPROMs inside microcontrollers are the more common thing today.
For a distortion analyzer, I have found the QuantAsylum QA403 to be a great device with outstanding performance. It is an example of a piece of hardware married to a PC via USB. In fact, it is also powered by the USB. As with an AP, the PC takes care of the human interface, permitting a lot of convenience and a human interface as sophisticated and multifunctional as you want. The USB side is galvanically isolated and I have seen no evidence of computer noise getting into the box. The QA403 is only $600.
Cheers,
Bob
Cheers,
Bob
The QA403 is on my to-buy bucket list, too - having said that, I looked closer and it will likely require a powered USB hub to run it, as it is a bit too much of a current hog to run from the usual USB interface.. I never liked the AP stuff that much - the user interface is a little on the difficult side. For 600 bucks, you get a lot for your money with the QA403.
Now you need a PC/laptop, USB hub, screen, KB, mouse, QA403, time to clear off or re-arrange the work bench.
It would be nice if you could use a QA403 similar in operation to a sound card.
Use the DAC section to be able to play music files (.wav,.mp3,.flac), stream on the pc = dual purpose/usage.
Play music through the amp that you have on the bench being tested, without the need to switch source cables, novel idea 🙂
Use the ADC section to record audio, sample those old LP"s, tapes, live from a mix or mics?
s/w features/upgrade or the h/w won't support it? More bang for the buck imo.
It would be nice if you could use a QA403 similar in operation to a sound card.
Use the DAC section to be able to play music files (.wav,.mp3,.flac), stream on the pc = dual purpose/usage.
Play music through the amp that you have on the bench being tested, without the need to switch source cables, novel idea 🙂
Use the ADC section to record audio, sample those old LP"s, tapes, live from a mix or mics?
s/w features/upgrade or the h/w won't support it? More bang for the buck imo.
You need a real, old school THD meter. An HP would be an excellent choice.
A Quantasylum shows a spectrum display, highly useful. I use an RTX 6001, same idea. I also use a ShibaSoku AD725C and an HP 339A. These instruments do other things and they do have an output that allows you to see a crossover notch on an oscilloscope. For other adjustments, these meters are easier to read than a spectrum display.
A Quantasylum shows a spectrum display, highly useful. I use an RTX 6001, same idea. I also use a ShibaSoku AD725C and an HP 339A. These instruments do other things and they do have an output that allows you to see a crossover notch on an oscilloscope. For other adjustments, these meters are easier to read than a spectrum display.
Hi Rick,
Sound cards require in input network. They can normally only handle about 5 V before damage may occur. That depends on the sound card of course. They also have about a 10K input impedance, plus for the input attenuator you need to compensate for input capacitance. I know, I've done it.
Calibrating a sound card can be done, but an audio processor has most of that done for you.
I can do all that with the RTX Rick. It sounds amazing, but it is an expensive DAC! You could probably do that with the AP or the Quantasylum.
Sound cards require in input network. They can normally only handle about 5 V before damage may occur. That depends on the sound card of course. They also have about a 10K input impedance, plus for the input attenuator you need to compensate for input capacitance. I know, I've done it.
Calibrating a sound card can be done, but an audio processor has most of that done for you.
I can do all that with the RTX Rick. It sounds amazing, but it is an expensive DAC! You could probably do that with the AP or the Quantasylum.
It would be, though I've never heard of it being done. When erased, all bits read high (1). Programming turns 1s to 0s, but only UV erasing turns 0s to 1s. Also, 12V needs to be applied to one of the pins to program it, and that was never wired up in-circuit, but only applied by a programmer.
The 8080 and Z80 happen to have the no-op instruction equal to hex 00. This was/is convenient in that you can (put the chip back into the programmer socket and) "zero out" other instructions with no-ops for debugging or whatever, without having to erase and reprogram the chip. The 6800 and 6502 have different values for nop, so that trick doesn't work with them.
Okay I have an old Amber 3401. My thinking is if it's below the Amber's residual, your probably good enough.
Been looking at Bob's old design and he is comparing his old design to the QA403. I thought he mentioned he has a QA401 too.
A QA403 handles a wide range of input levels
The QA403 is calibrated to input level.
That's my idea to use the QA403 as a $600 not so expensive audio DAC? probably, that's why I am asking if its possible or recommending this s/w upgrade 🙂
I have a hand wired eprom programmer that attached to the ole PC parallel port, code etc, = history museum
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Hi Rick,
Your Amber is a great THD meter. It would work great for looking at crossover discontinuities.
Yes, the QA40x is not a sound card, but an analyzer. Totally different kettle of fish. I see a huge number of DACs that are more expensive than a QA403. I have a Bluesound and I bet the QA would sound better.
Yep, it would probably work great, but for the higher volumes I was doing, something commercial was required.
Your Amber is a great THD meter. It would work great for looking at crossover discontinuities.
Yes, the QA40x is not a sound card, but an analyzer. Totally different kettle of fish. I see a huge number of DACs that are more expensive than a QA403. I have a Bluesound and I bet the QA would sound better.
Yep, it would probably work great, but for the higher volumes I was doing, something commercial was required.
Earlier posts mentioned the notion of "refreshing" data without having to erase. My instinct is that this is a risky shortcut. My suspicion is that programing will indeed renew the reliability of the "0" level but will be unable to correct charge leakage of the corresponding "1" state. I suspect the possibility of a "1" drifting into "0" would be unimproved by the programming refresh.
I've not researched this suspicion, so attach appropriate skepticism.