HP8560 HP-IB failure - Page 1
Forum section: electronics / testgear

author: Mr Simpleton
author_rank: Unknown
timestamp: September 26, 2013, 07:44:16 pm
content: Sigh... just received my "new" spectrum analyzer and got a NI 488-2 HS USB-GPIB dongle. Everything was running fine yesterday eve, but now not a tiny life over the HP-IB bus. Replaced the spec with a HP signal generator at the dongle and no problems finding the instrument when scanning the bus, but not a sign of life when looking for the 8560!Never had this kind of issues ever... Does anyone have an idea what might have happened??

author: G0HZU
author_rank: Super Contributor
timestamp: September 26, 2013, 08:57:53 pm
content: I haven't played with GPIB on an HP8560 for some time but can you make sure it is set to 'talker listener' and not 'system controller' in the GPIB options?Some HP instruments have both options.

author: Mr Simpleton
author_rank: Unknown
timestamp: September 26, 2013, 09:12:14 pm
content: Been browsing through the menus and have not seen this... I know I have to set it with the 8753 VNA when saving files on floppy. I haven't changed a thing since yesterday, and now even when I use the NI utility to scan the HP-IB no reply at all. Replaced the 8560 with another instrument and I have no problems to find it with the NI bus scan utility!I even tried to "plot" to my PC and use a logging program but no activity on the bus! Just to make sure, I have now installed the software on a second lap-top and still have the same issue, can see my signal generator but when replaced with the spectrum analyzer, nothing

author: G0HZU
author_rank: Super Contributor
timestamp: September 26, 2013, 09:42:45 pm
content: Doesn't sound good...This is a (desperate) long shot but have you tried disconnecting the 8560 from the mains (total switch off) and then repower it WITHOUT the GPIB cable and NI dongle fitted. Then connect the GPIB/dongle and try a scan?

author: Mr Simpleton
author_rank: Unknown
timestamp: September 26, 2013, 10:36:21 pm
content: Yes... been there, done that! Think I have tried all permutations possibleSo now need to get the CLIP and start looking at component level, I bet it is the HP-IB driver chip that given up.For me this is the first time in 30 years that I see a HP-IB/GPIB give up... there is always a first time

author: Mr Simpleton
author_rank: Unknown
timestamp: September 27, 2013, 08:43:46 am
content: Short update... took my lap-top to the office and had absolutely no problems connecting to the HP8568 analyzer... So unless there is a hidden function that switches off the comms on HP-IB, the instrument interface is gone

author: KJDS
author_rank: Super Contributor
timestamp: September 27, 2013, 03:04:47 pm
content: Are there a couple of UARTs between the connector and main GPIB chip? if so they might have died.I've got an assortment of agilent boards that I'm planning to scrap. If you're in the UK or Eu then I can post you sometihing if you can salvage some parts from it.

author: free_electron
author_rank: Super Contributor
timestamp: September 27, 2013, 05:49:28 pm
content: Quote from: KJDS on September 27, 2013, 03:04:47 pmwhat do uarts have to do with gpib ?UART : Universal asynchronous Receive / transmitter. in essence : serial ports.GPIb is a parallel bus .you mean bus drivers ? those will be 75162 75163's

author: KJDS
author_rank: Super Contributor
timestamp: September 27, 2013, 05:56:12 pm
content: Quote from: free_electron on September 27, 2013, 05:49:28 pmYou're right of course, I don't think I've ever looked at what happens at bit level on GPIB, just plugged the cables in and used or programmed it.

author: Mr Simpleton
author_rank: Unknown
timestamp: September 27, 2013, 06:30:40 pm
content: KJDS, thats a nice offer! Yup I'm in EU, and even got some Tesoel relays from you the other weekJust got my grubby lil fingers on service manual and CLIP so will have a look at the circuits tomorrow, my bet is that the driver circuits are gone.Right now I'm trying to get my focus on tomorrow mornings sheep herding competition... see if I survive it.

author: bingo600
author_rank: Super Contributor
timestamp: September 27, 2013, 06:40:41 pm
content: Quote from: Mr Simpleton on September 26, 2013, 09:12:14 pmJust a suggestion ....I think i saw something somewhere .... Mentioning to untick "identify this instrument" , if the instrument doesn't support *IDN?Could it be that your instrument isn't SCPI compliant , and you were lucky that it was unticked yesterday./Bingo

author: Mr Simpleton
author_rank: Unknown
timestamp: September 27, 2013, 06:48:25 pm
content: After a sip of my favourite IPA, Twisted Thistle, I just could not resist but had to look at the schematics.The GPIB controller seems to be a TMS9914 and the drivers are two, SN75160A and SN75161A Impossible to figure out if thes are DIL or SMD though...Update:Just realized there are two schematics in the docs... one using 75160/1 and the other 75160/2 and smd...Guess I have to crack this baby open to see whats inside

author: Mr Simpleton
author_rank: Unknown
timestamp: September 27, 2013, 06:53:11 pm
content: Bingo,the instrument HP-IB did work for a short period, but when I powered up yesterday evening, no response!Then NI utility allows to probe the bus, and see if anyting is alive on the bus even if it does not comply to the latest standards i.e. SCPI.Just to check computer and interface I hooked up a HP8568A and it found the instrument but complainded about no SCPI answer. And yes I could do a screen plot using Soft Plot.

author: echen1024
author_rank: Super Contributor
timestamp: September 27, 2013, 07:14:14 pm
content: What type of agilent boards I might be interested.

author: KJDS
author_rank: Super Contributor
timestamp: September 27, 2013, 07:53:27 pm
content: Quote from: echen1024 on September 27, 2013, 07:14:14 pmI've definitely got the board from a Agilent HP53310A Modulation domain analyzer.I've got a couple of E4406A Vector signal analyzers that i'll break tooand although I've not got any in bits at the moment, there are bound to be some from HP6632B sometime in the future.