Date   
Re: National Instruments GPIB-400

Harvey White
 

On 10/1/2019 5:39 PM, Bob Albert via Groups.Io wrote:
Thanks Harvey!  That shows clearly that building one or two of these isn't a trivial matter.
Not trivial, but quite doable....

The real problem is not so much the software, that can be written easily enough depending on your skill level, it's the 488 bus controller itself.  The TMS9914 and CB7210 are not readily available, although I do have enough for a board or so.  The 68488 is not a controller, which limits it.  If I were to go from scratch, and wanted to do the design more or less properly (and apologies to those who have taken the simpler route), I'd be designing for function and not necessarily cost.  It wouldn't be a product.  I'd use the appropriate (still available) drivers, an FPGA at about 11 dollars or so, I'd likely use an STMicro LK432 processor in the arduino nano format.  That gives me the USB input if I want to go that way, if not, then the Chinese made CH340 adaptors are inexpensive and go USB to TTL level serial.  The LK432 processor is likely far more than is needed, but I have a considerable infrastructure developed for ARM processors.

Having said that, it would seem that economics of scale ought to chop a bunch off the costs.  If it costs $40 to build one, then it should cost $40 to buy ten of them if they are cranked out in quantity.  This is proven time after time online with great stuff at what appears to be practically giveaway prices.
Note all the stuff that I said was "free".  Software development time, assembly time, and so on....


So my take on it remains to wait and see if the magic appears on this item.  And if not, I have plenty to keep my interests going at more than full blast.  My list of unfinished projects is daunting.  I need a reason to get at one or two of them at least.
I understand about unfinished projects, they all take time and some money.  I have an assortment of 488 capable test equipment, so I do have a need for a 488 controller.


From the antenna rotator to the synthesized signal generator to the VNA to the chart recorder and so on.  And someone is on the way to bring me some gear to repair.
I love this stuff!
Can't disagree.  Finished redesigning the FPGA for a modular test equipment monitoring design similar to a tricorder.  The FPGA handles LEDS, bidirectional I/O, neopixels, distance sensing, and serial/FIFO for the WIFI.  Still working on parts of it, but I went *very* modular with the VHDL.  Now that I have two versions (close to each other), it's time to go back to RF networking.

Harvey


Bob
On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <madyn@...> wrote:
On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
  Correct me if I am wrong, but it seems that the cables we are discussing are little more than some wire and a couple of connectors.  Perhaps there is some electronics in there as well; I suspect so.  But isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several
subsections.  Firstly, you have I/O drivers, getting the right ones is
important for driving more loads.  Next, you have the 488 chip itself.
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere.  FPGA of the right size may be
5 to 15 dollars.  Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then some.

Buy in quantity, fake some chips, you're lots cheaper.  Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is ridiculous.  I can buy USB devices that can read many memory card formats for a couple of dollars, and I suspect those aren't any simpler than a GPIB interface cable.  I can buy the nanoVNA for less than $50.  So the cost of the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The manufacturers have probably analyzed the market and have decided that it's better to sell a few at high prices than many at lower prices.  It's their call and I am not in a position to argue.  But I vote with my money and my money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of the market.  Value is important to me, if not to the big guys who do this stuff for a living (of which I used to be a part).
Bob
      On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <leo@...> wrote:
  On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo










Re: Tektronix 561B - is it a decent collectors item?

Cliff Carrie
 

The 561 / 564 family are very respectable 10 MHz mainframes, the first with two plug-in slots, I believe, one for the vertical and one for the horizontal.
They differ only in the power supply design and features.
561A: vacuum tube LV power supply. 561B: Solid-state LVPS (heat sink covering most of the rear of the instrument).
564A / 564B: Power supplies as above. Split-screen storage scopes. They use the CRT screen for waveform storage.
There is also a Mod 121 564B which has auto time delay (or external control) storage erase.
I never saw a bad cap in any of these, so leave well enough alone, I say. Okay, check the ESRs if you like.
The family uses similar power supplies, and there are two common weaknesses:
1. The main power transformer has a dedicated CRT filament winding which is elevated to -3300V, I believe. Moisture can cause the paper transformer insulation to become leaky and carbonize. This shuts down the HVPS (but does not necessarily damage it). The rest of the main transformer usually survives this also. A small filament transformer with a split bobbin (primary and secondary side by side, not one over another) can be substituted (contact me).
2. The HVPS transformer may fail, or it may simply develop a surface leakage path on the phenolic terminal boards. Inspect for carbon tracks, carefully scrape away all carbon and fill any tracks with epoxy.

The 561A was bought in quantity by IBM in the 1960s (for the IBM 1440 and 1460 mainframe families). It was the first dual-channel scope I ever used. My grandson has now inherited one of them from me and loves it. They (and their manuals) are great learning platforms. I also have a 564B and a 564B Mod 121, as well as a couple of dozen plug-ins, all working (including sampling). As for parts, the plug-ins are so cheap that buying a parts mule is often the best course. Collectible? They're almost indestructible. Of course my go-to scope today is a 7854.
Cliff

Re: National Instruments GPIB-400

Bob Albert
 

Thanks Harvey!  That shows clearly that building one or two of these isn't a trivial matter.
Having said that, it would seem that economics of scale ought to chop a bunch off the costs.  If it costs $40 to build one, then it should cost $40 to buy ten of them if they are cranked out in quantity.  This is proven time after time online with great stuff at what appears to be practically giveaway prices.
So my take on it remains to wait and see if the magic appears on this item.  And if not, I have plenty to keep my interests going at more than full blast.  My list of unfinished projects is daunting.  I need a reason to get at one or two of them at least.  From the antenna rotator to the synthesized signal generator to the VNA to the chart recorder and so on.  And someone is on the way to bring me some gear to repair.
I love this stuff!
Bob

On Tuesday, October 1, 2019, 02:17:43 PM PDT, Harvey White <madyn@...> wrote:


On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
  Correct me if I am wrong, but it seems that the cables we are discussing are little more than some wire and a couple of connectors.  Perhaps there is some electronics in there as well; I suspect so.  But isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several
subsections.  Firstly, you have I/O drivers, getting the right ones is
important for driving more loads.  Next, you have the 488 chip itself. 
I know of three of them that are specific controllers, and there's an
FPGA implementation out there somewhere.  FPGA of the right size may be
5 to 15 dollars.  Next, you need a USB to something interface, likely to
TTL serial data. You'd also (with at least the non FPGA versions, want a
processor to implement the conversion from the serial data to the
chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar
fifty per PC board (and that's Chinese special, no bigger than 100mm
square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff,
and 7 for major stuff like processors, and USB interfaces. Throw in
another five dollars for miscellaneous chips, ignore the connector,and
ignore the labor to put it together, and we've got 32 dollars and then some.

Buy in quantity, fake some chips, you're lots cheaper.  Throw in
assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is ridiculous.  I can buy USB devices that can read many memory card formats for a couple of dollars, and I suspect those aren't any simpler than a GPIB interface cable.  I can buy the nanoVNA for less than $50.  So the cost of the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The manufacturers have probably analyzed the market and have decided that it's better to sell a few at high prices than many at lower prices.  It's their call and I am not in a position to argue.  But I vote with my money and my money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of the market.  Value is important to me, if not to the big guys who do this stuff for a living (of which I used to be a part).
Bob
      On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <leo@...> wrote:
 
  On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo






Re: National Instruments GPIB-400

Harvey White
 

On 10/1/2019 12:40 PM, Bob Albert via Groups.Io wrote:
Correct me if I am wrong, but it seems that the cables we are discussing are little more than some wire and a couple of connectors.  Perhaps there is some electronics in there as well; I suspect so.  But isn't it maybe just level shifting?
Actually, it's a bit more than that.  You have at least several subsections.  Firstly, you have I/O drivers, getting the right ones is important for driving more loads.  Next, you have the 488 chip itself.  I know of three of them that are specific controllers, and there's an FPGA implementation out there somewhere.  FPGA of the right size may be 5 to 15 dollars.  Next, you need a USB to something interface, likely to TTL serial data. You'd also (with at least the non FPGA versions, want a processor to implement the conversion from the serial data to the chip/FPGA.  Throw in 3 to 7 dollars for that.  Ask at least a dollar fifty per PC board (and that's Chinese special, no bigger than 100mm square, including DHL shipping).

Don't throw in any money for software because we all know that's free.

so let's see, single quantity prices, say 20 dollars for the 488 stuff, and 7 for major stuff like processors, and USB interfaces. Throw in another five dollars for miscellaneous chips, ignore the connector,and ignore the labor to put it together, and we've got 32 dollars and then some.

Buy in quantity, fake some chips, you're lots cheaper.  Throw in assembly and a case, and you're less cheaper.

Harvey



I don't know the technical details but it does seem that even $100 is ridiculous.  I can buy USB devices that can read many memory card formats for a couple of dollars, and I suspect those aren't any simpler than a GPIB interface cable.  I can buy the nanoVNA for less than $50.  So the cost of the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The manufacturers have probably analyzed the market and have decided that it's better to sell a few at high prices than many at lower prices.  It's their call and I am not in a position to argue.  But I vote with my money and my money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of the market.  Value is important to me, if not to the big guys who do this stuff for a living (of which I used to be a part).
Bob
On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <leo@...> wrote:
On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo





Re: National Instruments GPIB-400

Reginald Beardsley
 

FWIW There is an entire EEVblog thread on the AR488 FW which is based on an Arduino Uno, but expanding to support the Mega 256, STM32F103, and others. Now that the author has completed a major update on the FW to simplify customization I'm going to add a number of features to control external relays, read a temperature and humidity sensor, real time clock and feed a strobe signal to synchronize measurements with the 34401As.

I'm also planning to rigorously test at least some (i.e. ATMEGA) implementations using a scope and 16500C logic analyzer against the IEEE specs.

The ATMEGA chips will source and sink 200 mA per package and 40 mA per pin at 5 V TTL levels without an external driver chip. That's 8 mA short of the IEEE driver chip per pin specs. The FW uses the Prologix command set with extensions. It won't run a full bus with 16 instruments at 3 mA per device, but should handle 10-12 and adding another one is cheap. In the past I'd been disdainful of the ATMEGA, but being able to operate *at* 5 V TTL logic levels rather than merely being 5 V tolerant has changed my opinion. They make great glue for old TTL gear.

There is an OSHW board designed by @vindoline who is handling the USA Cal Club Round 2 shipping if you want something bespoke. I used his when I was logging the Cal Club LTZ1000 references with a pair of 34401As. I recently completed one using a Chinese $6 Uno with ribbon cable and 2 IDC connectors. The SMD 328P Uno boards can source 200 mA whereas the DIP boards can only source 100 mA, though the latter can sink 200 mA.

I am building an automated switch and GPIB interface to run an annual cal suite on my test bench using a couple of Radiall ST6P SMA relays. I am adding the T&H and RTC support to simplify monitoring voltage references for some long term studies. I'll be using a Pi or Beagle to run everything and archive data from the cal runs as well as provide LAN access. That will provide far more functionality for $100 than any of the commercial offerings.

I'm hoping that someone will layout an OSHW Arduino shield that will allow connecting a 24 pin header to ribbon cable and IDC connectors so that it becomes possible to just buy some bits on ebay, assemble and program it with minimal fuss. Unfortunately, I already have too many projects to also spend time learning a PCB layout tool. Especially staring down the barrel of the Xilinx and Intel FPGA programming toolchains.

Have Fun!
Reg

Re: Tektronix 561B - is it a decent collectors item?

petertech99h
 

If you get to test the 561B, do it.  If filter caps are bad inside a 'bent trace' may appear, horse trade a little and repair it.If a buyer was sneaky, twist the horizontal trace position so it goes off screen before turning on, "oh, look it's broke",but nobody I know is sneaky! lol
'73
Pete

On Monday, September 30, 2019, 5:49:44 p.m. EDT, David Holland <david.w.holland@...> wrote:

*If* it all works, its probably worthwhile. (IMO).  The 560 series is
perfectly usable for what it is.  I don't believe the series suffers
from the same HV transformer problem Roy mentioned, I thought that
problem was limited to the 540's...

The caveats, the 3B3 and 3T7 both use tunnel diodes, and the 3S7 uses
sampling diodes (unsurprisingly).  I suspect they'd all be difficult
to source if things aren't working...

If you're satisfied with 10Mhz, its usable....  Mine works, and
they're simple enough to be still repairable...

<Shrug, IMO, YMMV, etc>

David

On Sun, Sep 29, 2019 at 10:27 PM <bradytmm@...> wrote:

Scope appears very clean, with 3A6 amplifier and 3B3 time base. Also includes a crusty looking Scope-Mobile 201-1 with drawer. The intriguing bit is the 3S7 sampler and 3T7 TDR sweep plug-ins (also looking somewhat crusty) sitting in the cart slots.
The scope belonged to a retired tech and appears to have been well cared for. The cart and TDR plug-ins not so much. Seller is asking $165 for the lot. Does this sound like a potential winner, or run away fast?
Thanks,
Tony


Re: National Instruments GPIB-400

Roy Thistle
 

On Tue, Oct 1, 2019 at 10:40 AM, Bob Albert wrote:


I see that it's more than a level shifter.
AFAIR it's TTL (a current sinking logic technology) levels... fairly high current (20 mA), open collector driver chips, for instruments to pull down the bus, in parallel... driver chips of a type not really seen now. But usually you don't need high current drivers if you don't want to run a full bus. There's a bunch of a bunch of projects to implement GPIB controllers (usually with limited current drive) on the Web, mostly using cheap microcontrollers. There's a bunch of threads about kluging one up, on the HP forum, and on the EEVblog.

Re: National Instruments GPIB-400

Leo Bodnar
 

There is a whole thread where people are comparing fake Agilent GPIBs against real ones. E.g. the fake one does not have internal EMI metallisation of the enclosure.

https://www.eevblog.com/forum/testgear/flood-of-new-agilent-82357b-gpib-usb-adaptors-on-ebay-the-real-deal/msg744004/#msg744004

As Bob said - nobody is going to change their opinion, but it's good to share facts and experience :)

Leo

Re: National Instruments GPIB-400

Ken Eckert
 

In the scientific equipment world HP/Agilent equipment that had HP/Agilent
PC software you had to use a HP/Agilent GPIB card. The software was
dependant on code residing in the adapter. If you used a NI card the
software would install okay, but never work.
I had spent many hours chasing that issue on a GC until the local Agilent
engineer "enlightened" me 😁

On Tuesday, October 1, 2019, Roy Thistle <roy.thistle@...>
wrote:

On Mon, Sep 30, 2019 at 09:47 AM, Bob Albert wrote:


am surprised that the Chinese haven't found a way to get around that.
I have seen... over the years, even in the limited market for GPIB...
several low priced IEEE 488, 8 bit, and 16 bit cards.. but they never
really seemed to take hold. My guesses for the reasons for that are as
follows. Unlike almost any card you wanted to plug into a PC, to make it
work, or do something (floppy, hard, disk controller... or serial, parallel
port) GPIB just wasn't in demand enough for importers to order more than a
relatively tiny amount of stock. It was more profitable to make, and there
was more demand for, the common card most people needed to make up a PC.
Another reason is that NI soon realized that the Chinese were doing, or
trying to do this, and also knew that these cards were almost always to be
used with N.I. drivers and software. (As the software provided with them,
especially for commanding instruments, was very sketchy... if provided at
all). For a time some cloning continued on, and then N.I. implemented ways
to verify the authenticity of the card attempting to run the newer (or
most) NI drivers or software. I think that pretty much killed the off the
clones.



Re: National Instruments GPIB-400

Roy Thistle
 

Don posted before me (I should have read the second page!)… but, yes, as he says... that is what happened with Windows... and why Microsoft moved to try to make OEMs (and succeeded with most, like Dell) to make OEMs burn serial numbers into ROM that Windows could query on finishing installation.

Re: National Instruments GPIB-400

Roy Thistle
 

On Tue, Oct 1, 2019 at 07:49 AM, Leo Bodnar wrote:


the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work
with them

They are real deal - from Agilent Technologies, Ins. themselves.
Unless there is something in the hardware that the drivers can query (like in N.I. products)… I reckon that there is no obvious way to determine the "authenticity" of the drivers on the disc... and any kid in Guangdong could fake the artwork, and burn the CDs, making hundreds of clones, from just one legit disc.

Re: National Instruments GPIB-400

Roy Thistle
 

On Mon, Sep 30, 2019 at 10:29 AM, Kyle Rhodes wrote:


It's super well made
AFAIK, the HP/Agilent USB (if that's what you are referring to)… they were never made in the U.S.... or at least not very many. They were always mostly manufactured elsewhere... China being one place. So if you mass produce something, under some kind of contract, and are of the type that would want to... what/who says you can't make more than you are supposed to... and then sell them. (Tell me it can't happen in China.) So essentially, unless there is a way to check the "authenticity" built in to the unit, as NI started to do, you essentially have the same thing as the "real" thing. Although, it doesn't have to be... there are probably plenty of fakes... but, if somebody gets one, like you describe... this is how it could be that that unit is mostly indistinguishable, from the "real" thing.

Re: National Instruments GPIB-400

Roy Thistle
 

On Mon, Sep 30, 2019 at 09:47 AM, Bob Albert wrote:


am surprised that the Chinese haven't found a way to get around that.
I have seen... over the years, even in the limited market for GPIB... several low priced IEEE 488, 8 bit, and 16 bit cards.. but they never really seemed to take hold. My guesses for the reasons for that are as follows. Unlike almost any card you wanted to plug into a PC, to make it work, or do something (floppy, hard, disk controller... or serial, parallel port) GPIB just wasn't in demand enough for importers to order more than a relatively tiny amount of stock. It was more profitable to make, and there was more demand for, the common card most people needed to make up a PC.
Another reason is that NI soon realized that the Chinese were doing, or trying to do this, and also knew that these cards were almost always to be used with N.I. drivers and software. (As the software provided with them, especially for commanding instruments, was very sketchy... if provided at all). For a time some cloning continued on, and then N.I. implemented ways to verify the authenticity of the card attempting to run the newer (or most) NI drivers or software. I think that pretty much killed the off the clones.

Re: National Instruments GPIB-400

Bob Albert
 

Everyone has his own take on this topic.  I will do without GPIB, at least for now.
One of my instruments had a problem with the GPIB section so I just removed it.  That one, of course, won't do GPIB any more.
While it's an interesting aspect of test equipment usage, my amateurish foolings around with this originally expensive stuff just doesn't need it enough to fork over even $20.
However, after investigating the link you offered (thanks for that), I see that it's more than a level shifter.  Not being a software guy, I confess to not finding it understandable.  Too bad, as I did entertain some thoughts of bringing my knowledge base more up to date.
Bob

On Tuesday, October 1, 2019, 10:28:36 AM PDT, Leo Bodnar <leo@...> wrote:

Bob,

You can (and I think you should) build one for $20 and be done with it http://dangerousprototypes.com/blog/2014/01/13/open-source-hardware-gpib-usb-adapter/ It will not be able to do what proper GPIB adapter can but it's not a problem - you don't need these features.

Few companies who built $100,000 instruments invested efforts and money into designing and making a contraption that would interface to clusters of these instruments (probably pushing $1m) and have the guts to sell this contraption for outrageous $500-$1000.  I don't take it as a declaration of war. I am happy that somebody can afford to hand over $1000 to NI or Tek or HP so that they continue working on whatever they are working on.
It's fine, seriously.
Personally, I won't use Chinese knock-off to connect to $50k instrument and I won't buy $1000 adapter to use with 50 year old junk I got from a eBay. But this is just me.

Leo

Re: National Instruments GPIB-400

Leo Bodnar
 

Bob,

You can (and I think you should) build one for $20 and be done with it http://dangerousprototypes.com/blog/2014/01/13/open-source-hardware-gpib-usb-adapter/ It will not be able to do what proper GPIB adapter can but it's not a problem - you don't need these features.

Few companies who built $100,000 instruments invested efforts and money into designing and making a contraption that would interface to clusters of these instruments (probably pushing $1m) and have the guts to sell this contraption for outrageous $500-$1000. I don't take it as a declaration of war. I am happy that somebody can afford to hand over $1000 to NI or Tek or HP so that they continue working on whatever they are working on.
It's fine, seriously.
Personally, I won't use Chinese knock-off to connect to $50k instrument and I won't buy $1000 adapter to use with 50 year old junk I got from a eBay. But this is just me.

Leo

Re: National Instruments GPIB-400

Don Bitters
 

It may be also the factory in China is producing the HP83527’s for HP/Agilent/Keysight for the 1st and 2nd shifts, but is also running an illegal 3rd shift for their own profit, and clones and copies from that. The original parts and labels would have been accounted for by inventory. Knockoff parts and labels would not have been counted. This is similar to what happened to Microsoft win WinXP and Win7 in China.
Don B

Re: National Instruments GPIB-400

Don Bitters
 

The curious thing to note is no serial number listed, not sure but I believe they had serial no’s. on them, and the certificate would have it. So odds are it is bogus.
Don Bitters

Re: National Instruments GPIB-400

Bob Albert
 

Correct me if I am wrong, but it seems that the cables we are discussing are little more than some wire and a couple of connectors.  Perhaps there is some electronics in there as well; I suspect so.  But isn't it maybe just level shifting?
I don't know the technical details but it does seem that even $100 is ridiculous.  I can buy USB devices that can read many memory card formats for a couple of dollars, and I suspect those aren't any simpler than a GPIB interface cable.  I can buy the nanoVNA for less than $50.  So the cost of the interface is definitely out of line.
Yes there are companies that buy things regardless of price.  The manufacturers have probably analyzed the market and have decided that it's better to sell a few at high prices than many at lower prices.  It's their call and I am not in a position to argue.  But I vote with my money and my money isn't voting for those.
Yes I am "just" a hobbyist and my monry isn't a significant fraction of the market.  Value is important to me, if not to the big guys who do this stuff for a living (of which I used to be a part).
Bob

On Tuesday, October 1, 2019, 07:49:32 AM PDT, Leo Bodnar <leo@...> wrote:

On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo

Re: CORRECTION: Tom Jobe Drag Racing Legend; WAS [TekScopes] Tom Job

Chuck Harris
 

Tom was a friend, and somehow I don't think he would approve of
us making a fuss about his passing. He was not big on self
promotion, much preferring to praise and promote others that he
enjoyed.

I sensed something was up about a year ago when he seemed to be
tidying up loose ends. The tone and tenor of his emails seemed
somehow a little different.

One of those loose ends was to give me his remaining stock of
fan collets he made for the 2465. They were made on one of his
CNC lathes, and are simply beautiful. I told him so, but as
was typical, he ignored my praise.

I have 4 or 5 left, and if anyone needs one, I would be happy to
send one on. I would prefer that they be used for a scope that
matters to you, and not just something you want to spiff up for
a sale.

Tom will be missed.

-Chuck Harris

Dennis Tillman W7PF wrote:

George Lydecker misspelled Tom Jobe's name in his original post.

Tom Jobe was a 15+ year member of, and regular contributor to, TekScopes.
He was legendary in drag racing. You can read more about him at this address:
https://www.hotrod.com/articles/farewell-drag-racing-legend-tom-jobe-1940-2019/

More from George:
Tom Jobe was indeed a valued member of, and a regular contributor to, TekScopes for the past 15 years. Tom came from an automotive career at Honda and electronics was a secondary passion. He became involved with our group through his interest in using and understanding oscilloscopes in the context repairing electronics systems in cars.

I’ll have to ask Trevor, Tom’s friend and now mine, about what he knows of this early history. In any aspect, Tom was a good and kind person whose company I enjoyed and will miss greatly.

Dennis Tillman W7PF

Re: National Instruments GPIB-400

Leo Bodnar
 

On Mon, Sep 30, 2019 at 12:56 AM, John Miles wrote:

Also worth noting that the Chinese clones (if that's what they are) of the
GPIB-USB-HS adapters come with a CD containing driver versions that will work with them
They are real deal - from Agilent Technologies, Ins. themselves.
http://www.leobodnar.com/files/IMG_8306.jpg

Leo