View Full Version : Olsen 595 Output Problems

11-26-2016, 11:22 PM
Another problem cropped up today. I had a bad cat5 connector so I fixed that. Now I can't get 2 of the channels on that output to work. Here is my setup:
2 Olsen 595's running from parallel port
Powered by a AT computer power supply
Using Brian's SSR's

The LED for the channels turns on but nothing out the "O" port for output 2 & 3. 1 & 4 work fine. I tested this using Dirknerkle's SSR/CAT-X tester. The LED's turn on the 595 board but not on the tester board. I swapped the 2803 & 595 one at a time from another working board and that didn't fix it. I looked for a schematic to see what actually drives the outputs. I am guessing it is the 2803 chip does that. Actually I swapped the 2803 first then I swapped the 595 with the 2803 still swapped.

Are there any troubleshooting steps that help with this online someplace?


11-27-2016, 09:36 AM
Dave, check back at you're other post, I left you a PDF file with schematic for the Grinch board, same as the 595 but without the led's.


11-27-2016, 10:04 AM
If you are using that schematic to help troubleshoot keep in mind that the Grinch board doesn't have the ULN2803 chips.

11-27-2016, 10:25 AM
I looked at the grinch schematic and realized it is different so can't really use it.

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11-27-2016, 12:29 PM
Here's a link to the thread that has the schematic in case you need it. Keep in mind there's more than one version. Not all versions had the channel LEDs on them.

Maybe this will help you out.


11-27-2016, 03:50 PM
Haven't tried anything yet but looking at that schematic I don't understand how the LED's come on but the output doesn't according to the tester. The 2803 provides a ground right with the resistor pack pulling up to 5 volts.

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11-27-2016, 08:49 PM
Yeah, there's not much left..

I couldn't find a picture that shows the traces on the bottom side of the board.. but I would do a continuity check on the 4 traces that go from the LEDs to the jack.

possibly a bad trace, pad, jack or cat 5 cable.


11-28-2016, 08:07 AM
Here's a picture of the traces for a 595 board. Maybe it will help with your trouble shooting.


12-01-2016, 08:06 PM
You are correct the 2803 drives the ssrs

think your problem may still be in the cat5 conector but i dont know much lol

if my old memory is working the leds onboard run off the 595"s

12-01-2016, 08:17 PM
Nope 595 feeds 2803 then leds then rj45 so if leds work whats next lol

12-03-2016, 10:12 PM
Nope 595 feeds 2803 then leds then rj45 so if leds work whats next lol Would have to disagree with you their. LED,s on this version are powered by 595s then the 2803s after. I have these boards, homemade from plans from here.

P. Short
12-03-2016, 10:36 PM
Based on the trace files from the wiki and provided by DVC2013, I'll agree with jmksparks.

12-03-2016, 10:49 PM
Thanks everybody for your replies. I hope to have a chance tomorrow afternoon to try swapping some chips out. No time during the week because the show starts right after I get home from work and was busy today Christmas shopping.

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12-03-2016, 11:24 PM
It sounds like there is at least a couple of versions of the board...

I dug up a post of a 595 with what appears to have the LED's after the ULN's. I believe it may be Macrosill's coop board...


Dave can you post a picture?

12-04-2016, 03:55 PM
So I swapped a "potential" good 2803 chip from another spare board and no change. I guess I should swap another known good chip on the same board. Anyway attached are pictures of the LED's on the Olsen and the tester, what board I have, and the traces showing the 2803 drives the Led's and the outputs.




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P. Short
12-04-2016, 04:03 PM
Looks like Ronp was right.

In any case, I would use a light and a magnifying glass to look inside the Rj45 connectors for the offending channels, checking for bent, corroded or otherwise damaged contacts. That is, if you haven't done this already. Also double-check for cold solder joints on the RJ45 connectors that may have decided to go open this year.

12-04-2016, 04:06 PM
Yeah. This board was purchased already built so could definitely be a cold joint or problems with the RJ45 connector.

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12-04-2016, 11:20 PM
So I found the problem. It was the RJ45 connectors. The stupid connectors that were used on this board. They have little fingers that the contacts are supposed to stay in but they get out of line and get stuck below the fingers and then don't spring back up to make contact with the connector. Apparently they didn't come from Mouser. Thanks for all your help.

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P. Short
12-04-2016, 11:58 PM
I'm glad that you found your problem.