Hp3582a CRT to convert to LCD - Page 1
Forum section: electronics / beginners

author: Sergio68
author_rank: Contributor
timestamp: December 11, 2024, 02:12:59 pm
content: HiI'm new here and first a quick presentation.I'm french car designer but also a huge passion for HIFI and electronics. I started 4-5 years ago to restore some hifi gear specially Sony ones.I have some projects that I would be happy to show you when finished completely...I bought a Panasonic Audio Analyzer VP7722a (really cool one) and a HP 3582a Spectrum analyzer, really amazing stuff. I love it but the CRT started to make som cracks noise while it was already very dim. Not possible to have at the same time text and trace...Looking at many examples of existing conversion if you have a solution to swap the screen or any experience in it I would be really happy.From my side I can help for 3D modeling or designing some parts for 3D printing.Thanks a lot.Serge

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 11, 2024, 02:26:01 pm
content: 3582A seems to use the famous "very blurry" 1340/1345A CRT unit.Simmconn makes an LCD conversion kit (expensive) but it doesn't seem to be supported.http://www.simmconnlabs.com/2001/2073.htmlwait to see what others have to say.

author: Sergio68
author_rank: Contributor
timestamp: December 11, 2024, 02:44:33 pm
content: I already had a chance to contact the Owner of simmconnlabs but like you said does not exist any kit and any for the future from him....Thank you for th answer !

author: CaptDon
author_rank: Super Contributor
timestamp: December 11, 2024, 02:56:50 pm
content: I'm not familiar with that unit. I am wondering, is it a normal raster scan or is it more like a vector scan similar to how an analog oscilloscope display works? Does it have any sort of video output on the rear panel such as VGA or composite NTSC? Is the original display monochrome or color? There are some very expensive color LCD replacements for Tektronix and a few others but those replacements are limited in what signals they can display. Many O.E.M. displays used oddball scan methods and frequencies. We are running into this problem with older pleasure craft C.R.T. radars as the C.R.T.'s are fading away, no new ones are being made and the best you can hope for is to find a used system for parts that has a good C.R.T. but not worth repair due to other issues. It seems a lot of HP gear and a few others are getting 'parted out' or scrapped due to fading C.R.T.'s.

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 11, 2024, 03:09:01 pm
content: 1345A is vector scan, but it is a CRT unit with uC, font ROM, etc. built in. controlled by 16-bit parallel(my memory).hp called it a “DIGITAL DISPLAY” and sold it as a stand-alone unit.You have to take a big gamble to buy a used one. because it is blurry and does not show a perfectly clear image even if you adjust it again.

author: Sergio68
author_rank: Contributor
timestamp: December 11, 2024, 03:43:12 pm
content: Thank you for your answers.It's a green CRT, no video outputs... nothing except X, Y, Pen for plotting on rear panel. It works like a scope tube as mentionned in the service manual. So vector scan...I didn't know about the 1345A but very intersting.In a post here I've read that a member "dxl" had made this swap succefully... but nithing more ;(

author: Sergio68
author_rank: Contributor
timestamp: December 12, 2024, 03:30:56 pm
content: Hello,Hope somebody will have a solution)))

author: ZhuraYuk
author_rank: Regular Contributor
timestamp: December 13, 2024, 01:37:07 pm
content: There is no solution except to build yours FPGA based converter or to fix 1345 display. I have HP 4145A and after making full adjustments including high voltage in 1345 and replacing some caps it shows quite nice sharp image.1345 is generally very reliable unit which can produce very sharp image 2048x2048 points on 5 inch display. It has 3 time related problems:1. Electrolytic caps2. Tantalum caps3. 0.5W 100 PPM resistors which go open

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 13, 2024, 02:07:03 pm
content: zhurayuk, can you tell me more about it?My 3562A, no matter how much I adjust it, is blurry.For now, I have replaced the tantalum and electrolytic. Resistors?

author: ZhuraYuk
author_rank: Regular Contributor
timestamp: December 13, 2024, 06:06:18 pm
content: This is how mine looks like, is it blurry enough for you ?The resistors are large ones, example is below, half of them were open in my unit.

author: Sergio68
author_rank: Contributor
timestamp: December 15, 2024, 10:36:42 pm
content: Hello.Very interesting and thank you for details. But because of many issues with contrôler card, high voltage and probably crt also, I’ll prefer to switch to lcd…That why I’m asking help.

author: Sergio68
author_rank: Contributor
timestamp: December 16, 2024, 01:41:15 pm
content: I would like to understand what to purchase first (hard) to fit the same specs of original crt. And maybe there is here somebody who already made code for FPGA...)))) Or similar to adapt....

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 16, 2024, 01:48:35 pm
content: !?Are you really going to modify it?I was adjusting my 3562A CRT all day today and i too wanted to go LCD.Quote from: ZhuraYuk on December 13, 2024, 06:06:18 pmmy 1345 was properly 27.4K.I took a bath and thought about it,1345A receive XY position and stroke commands, character commands and graphic commands. like HPGL. It has an MCS-48 for this purpose.it is feasible with a uC with an LTDC such as STM32/ATSAM and a 6.5” LCD.CRT seems to be able to specify a 2048x2048 XY position, but we do not need such a high resolution LCD. It will be blurry to begin with. XGA (1024x768) is sufficient.

author: Sergio68
author_rank: Contributor
timestamp: December 16, 2024, 02:49:01 pm
content: Ok thank you for the details. I really want to make the jump because I like this HP and I'm also intersted in learning... Actually it is not possible to use it....

author: TERRA Operative
author_rank: Super Contributor
timestamp: December 16, 2024, 05:14:46 pm
content: In the CRT's in my 4145A and 4145B, I found bad trimpots.After replacing all the electrolytic caps and the Bourns 3329 trimpots, they are nice and sharp again.

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 16, 2024, 05:44:29 pm
content: +task list. memo memo....

author: bsdphk
author_rank: Regular Contributor
timestamp: December 16, 2024, 08:38:22 pm
content: Quote from: squadchannel on December 16, 2024, 01:48:35 pmThe MCS-48 is only there to drive the self-test image(s), during regular operations it is held in reset by the "host-present" signal.The 1345A needs the host-computer to drive the sequence of instructions, and at the rate the display needs them, and they vary quite a bit in duration.It's an awkward rate things happen, too fast for interrupts on the microprocessors of the time and too slow for having the CPU stuck there driving an entire frame.So they created an option where an extra PCB makes it look like RAM from the host computer, and the logic on that board automatically starts displaying the instructions from location zero 60 times per second.This also adds new "instructions", interpreted by the logic on the new PCB, for jumps, which means you can enable and disable parts of the picture by jumping to them or past them. (The inspiration for the HP1345, the display module in the HP856 family is even smarter.)If you have the "RAM" version, it wouldn't be too hard to hook up an Rpi, have that simulate the RAM behaviour and then draw the instructions on it's LCD.If you do not have the "RAM" version, you can probably still do it, but it becomes much more involved.(Your instrument is designed to either the RAM or the non-RAM version, you dont get to choose that.)See also:https://phk.freebsd.dk/hacks/Wargames/

author: Sergio68
author_rank: Contributor
timestamp: December 17, 2024, 03:25:41 pm
content: Hi.Big thanks to all explanations.What I understand is that the modification can be done with either fpga, stm32/atsam or Rpi?And important is to check if there is a RAM.Resolution Is XGA…Screen should be 6,5 inches ….I’m not familiar with this kind of material, much more with audio équipements.Even code programs not familiar.Need help definitely;)))))

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 17, 2024, 05:05:36 pm
content: Hello Sergio68,As other members already undescored, an LCD 'off-the-shelf' replacement kit for the failing HP 3582a CRT seems not easily available.So I guess that if you want to upgrade with LCD you will have to build that kit yourself. It is far from an easy project and I also doubt that anyone will do it for you. Tweaking such a conversion kit needs to have the video signal available. This means that only people who also own a HP 3582a would be able to do that.As an alternative, it would be possible to digitize the video signal(s) and replay it with a powerful (multichannel ?) arbitrary generator. But this kind of stuff is not that common among electronic hobbyists.I would suggest that the first thing to do is to catch the service manual to find where the video signal(s) are located and then open your unit and probe this (these) signal(s) to know their exact shape and frequency.Even though I have very limited video knowledge, I would say that a good start would be to determine these features :[video gurus, please correct me if I'm wrong]- CVBS or RGB signal- if CVBS, only luminance or is there also chrominance (color information)- line frequency- frame/image frequency- interlaced image or not- sync pulses (separe signal; mixed with CVBS, sync on green, ...)After that, you can have a look tothis threadstarted by @DC1MCT, where @Trantraton (from Toulouse, France) works now for weeks to program a video processor/scaler in order to replace the old CRTs of Advantest SA.Helped by very skilled members on this forum, and after 6 weeks of harship, some encouraging results did show up just very recently (actually this week).But at the beginning, he also asked for help and nobody had an 'off-the-shelf' answer for him. He had to spit in his hands and devise himself an LCD kit for the specific requirements he has (as far as I remember : RGBS 15,8 kHz interlaced).I think you will have to follow a similar track.

author: bsdphk
author_rank: Regular Contributor
timestamp: December 17, 2024, 09:43:33 pm
content: Quote from: timeandfrequency on December 17, 2024, 05:05:36 pmYou are totally in the wrong part of town: This is not a raster scan display, it is a vector display.The available analog signals are X, Y and Z (=intensity).

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 17, 2024, 10:37:31 pm
content: Quote from: bsdphk on December 17, 2024, 09:43:33 pmOK, great to know.So @bsdphk, any hint and suggestion on how to digitze these signals and display the result on an LCD screen ?

author: Sergio68
author_rank: Contributor
timestamp: December 18, 2024, 10:48:55 am
content: Hello to all of you !First thank you for yours messages extremely intersting !I'm totally aware that making this modification is hard and requires knowledge and time. I either don't want to ask somebody to do the job for me but there are here skilled persons (like all of you) here to understand the conversion.I will do some experiments during vacations.... and let you informed!

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 18, 2024, 01:11:50 pm
content: There's clealy a trend about display overhaul of old TE where the functional/front end hardware is still of great value but the display sub-system becomes defective and no replacement parts are available.The concerned TE are mainly SA, VNA and some high-end metrology grade voltmeters. Some high-end counters, power meters, and RF & µWave generators might also require a display redesign.Since small CRTs are also very rare today, only LCD/TFT screens are a viable alternative.However, the path is often difficult: if the TE does not provide conventional video signals internally, custom video processing and image resizing are absolutely necessary.Several projects designed by very competent guys have been published on the Internet in recent years, and I hope that more articles will be available on this topic soon.Quite for each TE model, some tweaking and/or customization is still required.The retrocomputing and vintage arcade game scenes also have related needs.

author: bsdphk
author_rank: Regular Contributor
timestamp: December 19, 2024, 09:15:41 am
content: Quote from: timeandfrequency on December 17, 2024, 10:37:31 pmWell the cheating way is to buy a cheap LCD oscilloscope with a good XY mode, but the HP1345A is a pretty high-performance piece of work, so do not be surprised if "cheap" isn't particularly :-)The alternative, as I already mentioned above, is to go in at the digital interface and implement the commands yourself.It is not particularly hard, I did it for my reverse-engineering toolkit here:https://github.com/bsdphk/PyReveng3/tree/master/pyreveng/cpuBut personally, I wouldn't do it: I love the HP1345A vector æsthetic :-)

author: Sergio68
author_rank: Contributor
timestamp: December 19, 2024, 11:02:18 am
content: Hello timeandfrequency and bsdphkTotally agree with what you are saying and there is a dilemma between keeping original and “upgrade “ to more modern screen. Second option for me was motivated because of many issues in this crt part of the 3582a, with all the rest totally working. And I don’t want to throw out all… it’s a fantastic piece and updating with lcd could be really cool and also lighter (!)Basically I would like to test with a scope and after go deeper with a solution keeping all functions.So I was curious if connecting a scope to those points XY mode could produce something (see the photos, it’s the analog entries of the crt command card )There is no XY in the back, only plotter out commands.I’ll have a look on the link.Thanks a lot again !!!

author: squadchannel
author_rank: Frequent Contributor
timestamp: December 19, 2024, 11:13:25 am
content: Sorry, I determined from the front panel bezel that it was a 1345A, but apparently not.lcd drawing from XYZ, would need a high speed ADC.XY is just voltage vs XY position, Z is luminance.You can draw with a regular scope; if you input in XY mode, you will see the same thing. can't input the Z signal, the luminance will be constant.

author: Sergio68
author_rank: Contributor
timestamp: December 19, 2024, 12:15:15 pm
content: No worries ! Don’t be sorry.I’ll try to hook a scope.

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 19, 2024, 06:36:33 pm
content: Quote from: Sergio68 on December 19, 2024, 11:02:18 amSo, four signals on small coax cables. It would be interesting to know if the shields of these coax are all at the same potential.

author: Sergio68
author_rank: Contributor
timestamp: December 20, 2024, 12:31:45 pm
content: I’ll tell you what’s inside those wires.

author: bsdphk
author_rank: Regular Contributor
timestamp: December 20, 2024, 04:37:34 pm
content: Quote from: Sergio68 on December 19, 2024, 11:02:18 amThat picture is the HV drive card, that's not the right place.Try looking at J4 and J5 on A1, I think those are the aux X+Y outputs at 0-1V DC, and J3 seems to be the Z to go with them.The manual situation is somewhat messy for the 1345, because there are a number of different versions and options.Some of the better copies of the doc is included in other instruments manuals, notably the 3577 which may have been the first time it was used.On version had three 3-pin connectors where XYZ could be looped through external circuitry to multiplex analog signals, I think the 8981 may have used that model.Ohh, and one more thing: If your problem is "badly out of focus" you should check if there is an external focus pot attached, or if there should have been. Check the jumper (it's in the manual)

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: December 20, 2024, 06:47:44 pm
content: It would be so nice to provide some links to all of these service and user manuals

author: Sergio68
author_rank: Contributor
timestamp: December 20, 2024, 11:24:59 pm
content: Oh cool! Thanks a lot bsdphk!I’ll share the links for operating and service manuals.Of course and share more photos.Thanks again!

author: Sergio68
author_rank: Contributor
timestamp: December 25, 2024, 08:29:12 am
content: Hi! Christmas time…so very busy!Here the operation manual :https://www.artisantg.com/info/Agilent_3582A_Manual.pdf?srsltid=AfmBOor7U-n3wXG4w5s34k4_gLAB8ZTvHohyMD9vAgtpDL9F-0oWprLL

author: Sergio68
author_rank: Contributor
timestamp: December 25, 2024, 08:32:58 am
content: And service manual :http://www.petergottlieb.com/docs/hp/3582/hp3582a_svc.pdfI wish you a happy and merry Christmas !Thanks a lot for support.I’ll probably start soon some tests.

author: MathWizard
author_rank: Super Contributor
timestamp: January 15, 2025, 01:54:53 am
content: I know the basic's of CRT's, but not how all the data was encoded. So how did they do it on Tekronix DSO's with CRT's ? I guess the main board outputs some digital data to some DAC's that drive the vertical HV.So for 1980's scopes, what sort of data speeds, and how many channels and voltages would you have to monitor, to get all the data for an LCD ? So what size of say an AVR MCU, or STM32 would you need ? Would AVR even be fast enough, or maybe you would need a few of them.I'm just learning how my Stereo works, and writing some Assembly programs to help a few of it's IC's that are acting up. And I have a nice new fast DSlogicPro32 I want to try out on something, like my old Tektronix. In fact I'd make the screen bigger.