Why are GPIB-USB converters so dang expensive? - Page 1
Forum section: electronics / testgear

author: SharpEars
author_rank: Unknown
timestamp: November 14, 2014, 06:54:42 pm
content: Is there a cheaper way than to spend some $150 on a converter to be able to connect multiple GPIB (IEEE 488) devices to a modern PC?

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 14, 2014, 07:00:03 pm
content: 1) It's what the market will bear. Historically, instruments with GPIB have been the rather premium gear. People who can afford that class of gear wouldn't blink at only $150 for an interface.Of course, now that all that old GPIB gear is being replaced with newer, shinier (faster/cheaper/better/more features) gear, the landscape is different.2) The interface itself (hardware) is probably not a major part of the cost. You could do it with almost any $15 Arduino-type board.The big cost is probably the software drivers, which includes LIFECYCLE SUPPORT through all the revisions that the OS people (MS, Apple, et.al.) throw at you.At least that is my perception of the issue.

author: MarkL
author_rank: Unknown
timestamp: November 14, 2014, 08:36:09 pm
content: You can get a used HP GPIB PCI card (82350) for around US$50. But it is odd that the prices have stayed at those levels for years. An old PCI PC with linux and the linux-gpib package would make a fine GPIB server.The USB adapters are considerably more, probably due to their flexibility that they can be used on any computer. You can occasionally find a good deal on a USB adapter on ebay if you're patient.I wouldn't waste time on cheap Arduino or other wanna-be adapters. Many of them don't have the proper line drivers and can cause problems related to cable length, what devices are powered on/off, etc. It's not worth the aggravation to be diverted into debugging the GPIB when you're trying to get some measurements done, at least in my opinion.

author: bingo600
author_rank: Super Contributor
timestamp: November 14, 2014, 09:20:57 pm
content: I can recommend the Beiming adaptershttp://bmjd.biz/index.php?m=content&c=index&a=lists&catid=16I have 2 of those and a Genuine Agilent , all 3 performs super using linux-gpib.They all support Visa under M$ if using Agilents IO-LIBA bit strange they're not on *Bay at the moment , but they are nice quality with real NI 488 chip and the real GPIB drivers./Bingo

author: Macbeth
author_rank: Super Contributor
timestamp: November 14, 2014, 09:36:55 pm
content: I think this is an easy thing to make from an Arduino? I'll look into it as nobody else seems bothered!

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 14, 2014, 09:56:11 pm
content: Quote from: Macbeth on November 14, 2014, 09:36:55 pmGoogle returned "About 99,600 results" for a search on: arduino gpibIt would appear that a few people have been there already.The raw pins from the Atmel chip may not be up to driving long GPIB cables directly. May need a bi-directional buffer/line-driver, etc.

author: Macbeth
author_rank: Super Contributor
timestamp: November 14, 2014, 10:25:04 pm
content: Quote from: Richard Crowley on November 14, 2014, 09:56:11 pmWell, hot diggidy dang! Your are so right. Plenty of alternatives out there. I've never bothered as it looks as ancient as SCSI-1 and expensive cabling/connectors. All my bench devices use USB, except my HP6632B which is GPIB but has an RS232 port. If I had a 66xxA then I would be looking into this GPIB stuff. I'm sure I will eventually have to as collecting old test gear is pretty much turning into a hobby!

author: SharpEars
author_rank: Unknown
timestamp: November 14, 2014, 10:32:33 pm
content: Quote from: Macbeth on November 14, 2014, 10:25:04 pmOn the collecting old test gear turning into a hobby part, I'm way ahead of you brother!

author: mazurov
author_rank: Frequent Contributor
timestamp: November 14, 2014, 10:39:37 pm
content: Galvant Industries makes open sourced adapter, you can build/burn it yourself for the price of components and Microchip programmer.

author: bronson
author_rank: Regular Contributor
timestamp: November 15, 2014, 01:37:38 am
content: I have the Prologix, it works fine but is damned expensive.I keep meaning to buy another GPIB instrument so I can justify buying the Galvant:http://galvant.ca/shop/gpibusb/That seems like the right price for a decent product, and I'm more than happy to support open HW. Just wish it came with a case or was sick-of-beige sized.

author: Macbeth
author_rank: Super Contributor
timestamp: November 15, 2014, 01:52:00 am
content: Quote from: bronson on November 15, 2014, 01:37:38 amThat Galvant looks very well priced. But I thought GPIB/HPIB is networked, why would you need another hardware adapter when all you really need is the OS driver to support more devices? Surely for the price the Prologix would support that?