Hp 5004a and 5005a for Hp 3582a? - Page 1
Forum section: electronics / testgear

author: RNA
author_rank: Regular Contributor
timestamp: June 25, 2015, 01:05:46 am
content: HI everyone this is my first post!I have recently been given a free (but faulty) Hp 3582a spectrum analyser. It has scrambled text on the screen and a locked up front panel.Switching on the test button on the graphics card produces the AAAAA's on all four lines but no Square wave is shown.After taking out all the cards except the rom and processor I have checked every voltage that can be measured with the service manual and every thing seems ok.No ripple on any of the dc lines. The clocks are present in the tp1 and tp2 test points. The Single/both channel led does not change when switched.I have also checked with the scope the reset circuit for the initial turn on and this all looks ok.So now I am pretty sure my fault is with either the processor or the rom board.To progress with this repair I guess I will need to buy a 5004a signature analyser.So my question is can other analysers be used such as 5005a or 5006a? As these seem easier for me to get hold of.Also if any one who has experience in repairing these might have some ninja checks I could make any help would be appreciated.

author: PaulAm
author_rank: Frequent Contributor
timestamp: June 25, 2015, 12:25:25 pm
content: They all calculate the same signature. You can also use a Sony/Tektronix 308 which gives you an 8 bit LA to boot. If you get a 308, make sure it comes with the probes.Try not to pay too much. The last one I got (a 5005b) was $1/pound. Before that I got a dead 5004a for $20 that just needed a filter cap. These things are absolutely useless unless you're fixing equipment from that era that has signature data.

author: nctnico
author_rank: Super Contributor
timestamp: June 25, 2015, 12:31:09 pm
content: Before spending money I'd check the logic levels on the address and data bus. If you see nothing or levels only going half way then there is your problem.

author: MadTux
author_rank: Frequent Contributor
timestamp: June 25, 2015, 03:22:30 pm
content: And see if you can find the ROM images somewhere to make yourself a new set of EPROMs.That box has some real ROM madness inside, from what I've seen in the service manual, so chances are rather high that one of those EPROMs has leaked over the years. Bit rotten EPROMs produce all kind of funny problems.

author: free_electron
author_rank: Super Contributor
timestamp: June 25, 2015, 04:34:05 pm
content: if you want such an analyser i have those avaialble. i have both the 5004 5005 and the sony 308.

author: RNA
author_rank: Regular Contributor
timestamp: June 25, 2015, 07:58:27 pm
content: Yes i have the feeling its the rom chips as well. I might have got lucky as I found a cheap rom board on ebay. I know its a long shot but if it does not work out it will still be useful for spares. The seller says it came from a working machine and its the same version as mine.I am in the uk and can only find a 5004a for £120 ($188) LOL so i might have to contact you later free_electron if this rom board is hawked as well. Although i can not see many more HP kit coming my way.Burning fresh eproms sounds like a great idea although as of yet I can not find any rom imagesI will keep looking.I will report back and let you all know if the cheapest option works out.Thanks

author: RNA
author_rank: Regular Contributor
timestamp: July 24, 2015, 12:34:35 am
content: So by pure luck I managed to get hold of a CPU and ROM board but to no avail.The seller they had came from a working machine and with them in I have exactly the same results.So they are put to one side. I have checked all caps now for capacitance and ESR (out of circuit) and I have to say they are all really good.I have also re-soldered everything including the board connectors in the nests as the machine had been in a pretty grim store cupboard for about15 years.For my tests I only have 1 input installed, the ROM, CPU, RAM, Display processor/driver and the Analog display driver.I am not used to probing digital systems so maybe someone with knowledge might be able to steer me in the right direction.For those playing along I have taken a few pictures of the ROM, RAM and CPU edge connectors.The I/O bus all sits at 5V as do the outputs from the decoders. I presume thats because the CPU is stalled. I also do not have pcb extenders which is a real bind.SO before I buy a signature analyser is there anything else I might have overlooked?

author: PaulAm
author_rank: Frequent Contributor
timestamp: July 24, 2015, 12:47:48 pm
content: There's a 5004a on ebay now with a buy it now for $30. Even looks like it's working. The nice thing about the 5004a is the self test.no connection to seller, buy at your own risk yada yada

author: RNA
author_rank: Regular Contributor
timestamp: July 24, 2015, 02:26:41 pm
content: Yeah there are a lot of self tests on the 3582a, if you can get the processor turning lol

author: MarkL
author_rank: Unknown
timestamp: July 26, 2015, 10:36:38 pm
content: Quote from: RNA on July 24, 2015, 02:26:41 pmI think what PaulAm meant is that there's a self test on the 5004A. You can plug the probes into test points on the front panel of the 5004A to verify it's working correctly before proceeding with the DUT.The 5006A has this feature too, but the 5005A doesn't.

author: RNA
author_rank: Regular Contributor
timestamp: July 27, 2015, 12:05:35 pm
content: Yes I understood PaulAm. I have managed to get hold of a 5004a cheap from Sweden (with a passed self test) so soon I can have a dig around the digitals. All i need to find now is an extender board. Can the edge connector socket be bought? Maybe I could etch my own extender board?

author: PaulAm
author_rank: Frequent Contributor
timestamp: July 27, 2015, 05:04:06 pm
content: You might have to look around a bit for a connector. I think a lot of those were 0.156 inch spacing; still available, but not so common today. See if you can find a caliper and measure them. That would be just under 4mm (3.96mm) spacing.

author: RNA
author_rank: Regular Contributor
timestamp: July 27, 2015, 05:53:20 pm
content: I have just found this uk websitehttp://electrojumble.org.uk/Extender_Boards.htmThey hire many types of extender boards at around £4 per week.So it looks like I will be all set for a good probing session soon.

author: RNA
author_rank: Regular Contributor
timestamp: July 29, 2015, 05:50:00 pm
content: The stars are starting to align.....my hired extender board just arrived.

author: RNA
author_rank: Regular Contributor
timestamp: August 05, 2015, 01:01:25 am
content: Well I have some interesting news. I checked the processor and ROM boards which all seemed ok.However there were a couple of readings in the ROM which were a digit out, could this be a typo?The main problem I have found so far though was on RAM ic U10. This had an unstable reading onthe WRITE pin of the Data Line. I unsoldered this chip and the one next to it, added sockets and retested with the sameresults. When I then swapped round the 2 RAM chips the fault followed the IC. So this IC is definitelyfaulty. It is labeled /927 1818-0508.Does this seem a likely candidate for my symptoms? And are these unobtainium?

author: RNA
author_rank: Regular Contributor
timestamp: August 05, 2015, 01:28:56 am
content: These id's are MM5280N-5 4k ram. I found a US seller on ebay so I have bought a couple.Now for an agonising wait.......

author: RNA
author_rank: Regular Contributor
timestamp: August 13, 2015, 09:51:21 pm
content: First the good news.The RAM chip was indeed faulty. With the new chip in I had a working processor, a flashing data loading light, the front panel was unlocked and the 4 text lines were restored to the correct info for normal use. The graphic display however was not showing any sign of life.I took the opportunity to run some of the self checks (ROM and RAM) which all passed ok.The bad news is whilst going through the first signature analysis check on the ASM circuits I lost all image to the screen. DOH!The Data Loading light is still running so the processor is happy and currently I have a feeling it was a D-type flip flop which failed which does the character ROM latch.I also have a suspicion that the graphic problem is due to another D-type flip flop with the same part code. Coincidence?I am guessing these are early CMOS. Does anyone have any 1980's CMOS tales?

author: RNA
author_rank: Regular Contributor
timestamp: August 25, 2015, 11:22:44 pm
content: Ok, so I replaced the flip flops and I then had good looking signals all the way down to the video multiplexor switches. There were no outputs on these switches. They feed directly to the x, y and z high voltage amplifiers. These were the LF13201n, a bit difficult to find. Originally I believe one of these was responsible for the lack of graphic line. The other died whilst I was in the second test mode of the display board. In a way I am glad second died before I found the other fault as I am sure this would have died pretty soon.So to recap, originally there were 2 faults. A dodgy 4k ram chip and one of the multiplexors. Whilst trouble-shooting, a d-type flipflop died as well as the second multiplexor. The flip flop probably due to a careless slip of the probe? And the LF13201 probably due to age.As this was my first attempt at fixing something like this I am pretty pleased and enjoyed every minute. It was a great introduction to digital systems because of its more discreet nature. Thanks for everyone's help...now to hawk ebay's spares repair section!

author: TheSteve
author_rank: Unknown
timestamp: August 26, 2015, 12:17:19 am
content: Well done!It is almost an addiction I tell you.

author: VK5RC
author_rank: Unknown
timestamp: August 26, 2015, 03:17:18 am
content: Great job, every repair job I have done, (only a few complex ones) has taught me a lot. And you have saved a classic going to landfill!

author: RNA
author_rank: Regular Contributor
timestamp: August 30, 2015, 11:06:26 pm
content: I managed to use the 3582a in a video. Actually using the thing is even more fun than repairing it!!This is a repair of a 1980's Soviet mono synth!http://youtu.be/sowKJy4wdxA

author: scopeman
author_rank: Frequent Contributor
timestamp: February 05, 2018, 02:20:13 am
content: This is really cool. I know the guy that was the project leader on the HP3582A. Great to see that someone is using one!SamW3OHM

author: cizeta59
author_rank: Newbie
timestamp: March 03, 2018, 01:13:26 am
content: Hi everyone, I'm looking at the abnormal behavior of an HP3582A that does not have any characters on the screen. I'm following the path made by RNA in its repair told in this post. I recognized the LF13201N (1820-1941) on the A10 board, but I have no information for locating the F / F type D character ROM broken latches. Can I have the position and the board number, and also the HP code?Unfortunately I do not have the signature analyzer available at this moment.Thanks from Italy!

author: cizeta59
author_rank: Newbie
timestamp: March 03, 2018, 01:37:31 am
content: I found four 74ls174 (D f / f) on the A10 board, but also five 74LS273 on board A9 ....According to the wiring diagram they should be on board A9: SN74LS273N, position U7, U17, U1, U2, U19 ...

author: dxl
author_rank: Regular Contributor
timestamp: March 27, 2018, 06:38:03 pm
content: Hi,Quote from: scopeman on February 05, 2018, 02:20:13 ami'm also a user of the HP3582A. But my device is a bit modified - the picture tube was broken during shipment, so i developed a replacement TFT with a FPGA as controller. Nowadays this is easy as almost all of the devices in the 80ies/90ies are already using some VGA or similar graphics. But the HP3582A uses a scope tube, that draws two pictures: on graphics pictures, and the text as second picture. Was quite fun to write VHDL code that translates that. I'm attaching a picture of the early stages - the current one also interpolates the pixels so the graph looks a bit better.It's quite interesting how much logic you had to use to display characters on screen. My deepest respect to the people at that time inventing such stuff.

author: Rax
author_rank: Super Contributor
timestamp: November 15, 2021, 12:46:27 am
content: This is some really cool work. Did you consider packaging this up for others to implement? It'd be really neat to have a kit + software to replace the CRT with TFT on these units.