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-   -   Gould 1604 / 1624 Oscilloscope Problems (https://www.vintage-radio.net/forum/showthread.php?t=76450)

John Engineer 16th Nov 2011 10:50 am

Gould 1604 / 1624 Oscilloscope Problems
 
Hello
THIS POST IS TO HELP OTHERS WITH 1624 GOULD SCOPE

I own two Gould Oscilloscopes, 1604 & 1624
I use to work for Gould back in 1989 In the test & service department.

I have full services manuals & a full range of Eproms of different software revisions for the two scope's and the add on modules that plug on back of the scope. If anyone needs software updates I can send you eproms if you let me know what version you need.

Both of my scope's have developed strange faults over a period of time which puzzled me, the 1624 would not work with modules plugged into the back, no LED's on front panel, and no crt, thus the 4 channel Diff stopped working due to wave form module not working. If I removed both rear modules scope would
work, but seemed sluggish and I knew deep down there was problems. After digging out the service manuals and inspecting the main board, the first thing I noticed was the battery had leaked on to the pcb and was not reading a good voltage.

I removed the battery and ordered a replacement new battery, the design of these batteries are very poor because they are not sealed! and the acid erodes the pcb tracks on the main mother board. It has caused lots of damage to my pcb. I have chosen to take fly leads away from the pcb and place the new battery nowhere near the main motherboard and wrap the battery in insulating tape.

The same problem I found in the waveform processor module, tracks destroyed and acid leaking all over the pcb !! after replacing all the damaged tracks in both the waveform module pack and on the main mother board with very fine pcb wire. I still had the same problem whereby the scope would not power up ??

I needed to look closer at what was happening, so I started to probe around with a scope on the wave for pack and could see some very strange looking waveforms on the KROME & the scope main Processor E & Q pins. they were floating at about 2.5 volts with very strange waveforms on these pins. I knew they should be 5v data/chip select lines. All these bad signals were coming out the scope on the two rear module connectors.

So I started to cut pins on ic's on the main board and rewire the tracks one by one to each IC where I had isolated the pins from the main pcb for all given problem signals found. I also had to cut tracks going to the rear module connectors and rewire the tracks to the IC's. After creating lots of new tracks and what seemed like minor brain surgery, when looking at on these previous problem pins I had lost the 2.5 volt floating levels and could good looking 5v waveforms.

I also rewired many new tracks in the waveform processor around the battery plugged in the module and hey presto the 1624 scope was all back working again.

It turns out the battery leaking on the main board and in the waveform processor was causing the damaged tracks by battery acid to cross talk and induce strange levels between the pcb tracks. The only cure was to isolate these tracks to IC's and rewire the tracks.

I can stress how important it is to lift this battery of the main mother board, if you own a Gould 16xx Oscilloscope please add fly leads to this battery and get it away from the main motherboard and seal the battery. It will destroy your scope if you leave it on the board !

It's a little more harder to over come the very tight space in the wave form module, though Im thinking of having the battery out side the waveform module case on fly leads to prevent further damage.

So I was very pleased to have rebuilt and brought my 1624 back to life after a fault that had bugged me for a few years.

This took me quite a few hours and brain power to get to the bottom of what was wrong as there was multiple issues on the main motherboard and in the wave form module due to battery damage.

I hope this can help others who own the 16xx gould scope, this is a major design flaw with both gould and varta who make these horrible batteries.

There must be many other scopes out there with the same problems.

I have a very strange issue with my 1604 Scope, please see my 2nd post for full details.

If anyone can help me It will be very much appreciated,

Thank you

scirturbo 5th Sep 2012 4:08 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
This is good news! Finally some documentation available.
I own a 1604 with a 260 WP and RS423. I couldn't find a keypad to control the WP so I made a keypad using a micro controller and lots of tactile switches. Stan was so kind to give me a hex dump of the 260 WP which turned the 160 WP into a 260 (hardware is the same).
The service manual of the 260 and other info of helpfull members gave me enough info to construct the keypad and code.

I wonder if you have any firmware upgrade for my scope. The scope uses 3.53 , keypad and rs423 3.54

Simon

oplink1 27th Nov 2013 3:16 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Hello John,

Do you still have the Service manual for the Gould 1624? If so, may I purchase a copy from you?

Thanks.

Station X 27th Nov 2013 3:25 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Hello and welcome to the forums.

John Engineer hasn't been active on the forums for over two years, so he's unlikely to see your post.

However you should be able to email him by clicking on his username.

euleken 29th Nov 2013 11:19 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Hello oplink1,

the scope 1624 is similar as type 1604 except the differential inputs. Main circuits are the same and you can use the service manual found here for free:
http://www.eserviceinfo.com/download...1602/1604.html

The problems with the battery described by John seems to be a general problem with older Gould scopes. I have a 1604 and a 4074 with waveform processor and all batteries were leakage and have destroyed the PCB.
Likely John I have placed new batteries (160mAh, NiMH) away from the pcb and the scopes are working fine. :)

Ralf

WME_bill 30th Nov 2013 2:01 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Gould 1602/1604 The service manual source quoted by Ralf "euleken" does not have the parts list pages, pp68 even numbers onwards. I have the missing pages, but the files is too large to post, but can be sent by email. I am surprised that "oplink1" hasn't found the link to the discussion under Gould 1602 from 6th November 2013, which he may find helpful. wme_bill m0wpn

UweHerc 3rd Feb 2015 9:39 am

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Hello,

I would need a copy of the service manual for Gould 1602/1604 too.
I found a scan of the pages 1 to 68, but I would need the pages 69 to 138 too.
Is there anybody who could send me the missing pages via email please?

Thanks a lot,

Uwe

Freya 4th Feb 2015 10:22 am

Re: Gould 1604 / 1624 Oscilloscope Problems
 
I have even Pages 68 to 113; PM me with your email if you require these. Kindly provided to me by WME_bill a year or so ago.

WME_bill 4th Feb 2015 6:04 pm

Re: Gould 1604 / 1624 Oscilloscope Problems
 
gould 1602/1604. Manual
The missing even pages 68 to 131. I am glad that Freya is able to help UweHerc out. It is nice when you see something you provided last year is still proving useful to others. It fact, I am providing the same pages to Chris55000 following a private message.
Perhaps it highlights that it is much nicer for everyone if calls for help are posted on the Forum. It increases the number of people who might be able to help. wme_bill m0wpn

Station X 29th Oct 2015 9:34 am

Re: Gould 1604 / 1624 Oscilloscope Problems
 
One post moved to a new thread here:-

https://www.vintage-radio.net/forum/...d.php?t=120701

trh01uk 29th Oct 2015 9:51 am

Re: Gould 1604 / 1624 Oscilloscope Problems
 
Quote:

Originally Posted by John Engineer (Post 480682)
There must be many other scopes out there with the same problems.

John,

yes, and I bought some of them from new when I worked for Racal in the 1980s. Gould scopes had excellent facilities - some had 4 channels - some had inbuilt printers. These were fairly revolutionary features for those who couldn't stretch to the world of Tektronix.

However, we noted that Gould scopes consistently failed after a few years use. We got tired of sending them out for repairs. In short, they were seriously unreliable. So we stopped buying them. I presume others did too - since Gould seems to have vanished from the market place since.


Richard


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