Gould 1604 waveform processor

[scirturbo]

I finally got my broken 1604 fixed. Had to replace some components of the channel 1 input but also a logic component which had a short(?). The powersupply had some dry caps in the +/-12V section. This solved the focus problem which was only good when it was fully warmed up.

I found a manual on the net in german (no problem for me) and I hooked up the rs423 serial port to my pc and tried the various commands which are working fine! This scope has also a waveform processor on the back which could do some nice calculations on the signals. Problem is that most of the commands for the processor option let the microcontroller hang or reset. Some do work. I think it has a bad or corrupted eprom, 27c512. So my question is has anyone a dump of this eprom or a waveform processor that they are willing to sell?

It's labelled with: Gould 1600/160A (105), Processor Interface (memory)
eprom is labelled with: pn48056a, u2-k160a, iss 2.54

Thanks,

[Oldtestgear]

I may have a spare EPROM in my spares box. Do you have an EPROM reader to do a checksum on the suspect EPROM?

I will look tomorrow & send you a message. My 1604 has a problem with Channel 1 i/p. Could you let have a copy of the schematics?

Will get back to you.

Phil

[scirturbo]

I have a programmer but i don't know if it can do a checksum. I'll check this.
Sorry but I don't have a schematic. I only found the user manual on line.
Problem with my input was a bad FET. I think it was a J108 N-CHANNEL JFET or equivalent. I do remember it had a strange low resistance between D and S when measured with a dmm.
Hope this helps...

Simon

[Electrical]

Hello Simon
I too have a Gould 1604 with the 260 processor interface (Memory) but I do not have the 260 key pad and have similar problems without the key pad connected as there are additional GPIB/RS423 commands when the waveform processor is fitted, However I do have a copy of the 160A waveform processor manual, please find attached a copy of the additional command set for the 1604. I can scan the manual, which includes the circuits of the keypad if you wish, however it contains 45 pages so it will take some time to scan.
Phil I also have the circuits for the 1602/4 and I can scan the relevant pages for you, as the manual contains hundreds of pages, it would take too long to scan it all.

Regards Stan.

[Oldtestgear]

Stan,
Thanks for the offer. I only "need" the schematics plus if possible the calibration schedule for the input stage.
The waveform processor seems to be a rare find. Must admit mine dos seem to cause problems whenever I connect it up. I have a later revision of the EPROM -- in fact there seems to have been quite a few changes which is never a good sign.
My EPROM is marked iss 3.53. If anyone is interested in trying this revision, just let me know.

Phil

[Electrical]

Hello Phil
I have scanned the input stage drawings of the 1604 for you. He original drawings are A3 so I have scanned then in overlapping A4, the quality is not too good as the originals are a copy of a copy, also when I converted them to a PDF they have ended up in the wrong order, but I am sure they are all there.
I will have a look and see if I can find the set up and calibration sections for the channels but I am sure the channels are self, calibrating and the software checks the A to D converters on power up.
I hope this information helps and if you need any more sections scanned let me know.

Regards Stan.

[Electrical]

Hello Phil
I have scanned section 4 on calibration for you, please see attached PDF, again I seem to have the pages in the wrong order, I will learn how to do it one day.
With reference to the waveform processor, my scope needs the Type 260 waveform processor and the software No. in, the 1600/260(205) processor interface (Memory) is Issue 3.54 ROM PN480554. I did try using it with a 160A keypad but only the cursor functions worked.
With reference to the repair of channel 1, if you only have to change the FET, the auto calibration may cope, but if any of the resistor or capacitors need, replacing, it may be a rather complex set up. When you find he fault if may be easier to check all the channels with the same signal applied and then force an auto calibration, then check the voltage levels with the cursor and do some comparative checks before any adjustments.
Again I hope the information helps.

Regards Stan.

[Oldtestgear]

Hi Stan,
Thanks for the scans. My last excuse for not sorting it out has now gone....


Phil

[scirturbo]

Hi Stan,

The manual has a big section explaning the commands for the 160 interface but no circuit diagram/description. If you would be so kind to scan just the circuit diagrams. I do have a manual of the 170 keypad in pdf so if anyone want this just let me know.
If you don't have a 260 keypad you could try using the serial commands. They should control it the same way as the keypad.

About the input section, I found some pictures of it after my repair (two years ago) and it seems I also replaced two resistors. The fet is a strange one. Acc to the datasheet it's normally closed(?). Hope this helps in finding the problem.

Simon

[Electrical]

Hello Simon
I have scanned the 160A waveform processor manual, but it is too big to post, so I have split it into two parts, which includes the diagrams of the interface and keypad. On page 15 there is a list of additional commands to use when using the GPIB/RS423 interface, however there could be a problem with software compatibility, as the manual I have is older than my scope.
Please find attached two PDF files containing the complete manual and drawings. You may find some of the pages are not in the correct order, but they are all there.
I hope this helps.

Regards Stan.

[Oldtestgear]

Got the 1604 out today to check my waveform processor and other stuff. After 2 mins there was black smoke & the smell of burning tant cap. Now have to do a full repair before I can use it again.

These old Gould scopes are a pain.................

Thank heavens for the £12 TEK 485 I got earlier this year.

Phil

[scirturbo]

Yes they are. When I first saw the inside of it I was a bit intimidated of the huge amount of ic's. I thought I'd never get it fixed and no service manual or schematic to be found! In the end just measuring with only a dmm and lots of luck I managed to get it up and running.
The WP is still a puzzle to me but i'll continue.....

Stan, thanks for the the manual although the schematic is bit hard to follow. Maybe a scan from a scan? Btw my 1604 firmware rev is 3.53

Simon

[Electrical]

Hello Simon
I have increased the size of the drawings using a photocopier, three times; I hope you will be able to read them. The original manual is about the size of the keypad so the diagrams were not too big. I forgot to mention that I had posted the diagrams for the input channels and the calibration procedure for Phil; I hope they may be of use to you. With reference to the software in my scope it’s revision 3.56, so it’s possible there are lots of versions out there.
Phil
The shorted tantalum capacitors are the easy faults to find, just look for the burnt capacitor and replace it with an electrolytic capacitor if it is used as a decoupling capacitor, which I am sure it will be. I hope you switched of quickly before any resistors cooked as well.
Please find attached enlarged JPG files of the Keypad and Processor diagrams.

Regards Stan.

[electroanorak]

Hi there,

if you have a copy of the manual for this, I would be greatfull if you could let me know where you got it. My 1604 has lost its timebase on the non-storage setting and the timebase speed does not function.

Good luck with yours.

Thanks.

Daniel.

[scirturbo]

Hi,

I guess you need a service manual for that problem or a schematic. I can only help you with a user manual. You can download it here: www.eserviceinfo.com. Unfortunatly it's in german!!

To Stan, thanks for the clear pictures of the schematics. It's easy to follow now how things are connected and why. Also the cal. procedure is very helpfull. Do you have any info/schematic of the cpu (68B09)?

regards

Simon

[Electrical]

Hello Simon
Please find attached a PDF of the 1604 CPU Drawings. I also have drawings of the GPIB option and the RS423 option; I can scan these if it would help.
Hello Daniel
I have a complete set of drawings and a service manual for the Gould 1600 series scopes, but it is quite old, it is about version 2.5*. It is also quite large but I can copy the relevant sections for you, please see JPG file of main system block diagram and let me know which sections you are interested in.

Regards Stan.

[dazzlevision]

Hello Stan (Valveman49),

I have a Gould 1624 (with the 4 channel differential inputs underbelly) and it will not accept setting the date and time - otherwise working normally. I've replaced the NiCd memory retention cells.

If you could have a look through the circuit description part of your 1604 manual, to see what controls this, I'd be most grateful for a scan of the relevant text and circuitry.

Thanks in anticipation,

Dazzlevision

[Electrical]

Hello Dazzlevision
On the 1604 the real time clock module is inside the Processor Interface (Memory) module fitted to the rear of the scope, this is an optional unit, which comes with a Keypad and gives the scope a number of math facilities, please see the PDF of the manual in the earlier post. The real time clock chip is U5 in the processor diagram also in an earlier post. If this module is fitted remove it and check it’s internal 3.6-volt ni-cad battery. Without this module the scope will not retain the time when switched off. If I have not answered the correct problem please let me know and I will have another look at the manuals.

Regards Stan.

[electroanorak]

Hi valveman49,

Thank you for the offer. It is the timebase section that I have a problem with. That is Fig 6.8 on the block diagram.

Thank you.

Daniel.

[Electrical]

Hello Daniel
Please find attached a PDF file of the timebase sections for the 1604 scope, also the fault finding flow diagram from section 5.
I hope this helps. Regards Stan.