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$12.99 Telebyte RS-232 Opto-ISolator model 269
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Author:  tomk [ Sat Nov 13, 2004 1:56 pm GMT EthGMT ]
Post subject:  $12.99 Telebyte RS-232 Opto-ISolator model 269

This isolator is on ebay. It is a "port powered" and will not work on the STXR without modification. I found the internal power supply was not working with the STXR output apparently the output levels are not high enough. But the good news it is only used when sending data TO the STXR which isn't necessary. It has a DB-25 on end and a RJ-12 (standard phone connector) on the other. I connected the RJ-12 side to the STXR, DB-25 to the computer. The modification involves prying the Isolator's case open and removing the power supply IC which is the large vertical black IC with pins only on one end nearest the RJ-12. You can carefully unsolder it or cut it up with diagonal pliers (watch for flying pieces!). I made a cable to connect to the STXR from a 4 wire phone cord. Cut one end off, connect the following wires to a male DA-9 connector, Red to pin 3, Green to pin 2, Yellow to pin 5. It may or may not be worth all the work but I already had it.

Author:  Solar Guppy [ Sat Nov 13, 2004 4:01 pm GMT EthGMT ]
Post subject: 

Sound like you hacked the isolator to make it a straight thru connection :shock:

The isolation IS needed on the output , the Suntie does not process incomming data ... it only outputs a packet stream once a second

Please use the isolator listed in the Fishbowl documentation , or don't use Fishbowl [-X as it is part of the terms of use to use a properly working opto isolator

Author:  tomk [ Thu Nov 18, 2004 4:00 pm GMT EthGMT ]
Post subject: 

The Isolation hasn't been compromised. Just the ability to send serial data to the ST. The Telebyte Isolator uses 2, HP 6N139 optical Isolators rated at 2500V. One is used for sending data from and one for receiving data to the computer. For sending this unit connects the TD lines (from the computer, St) to the respective isolator photo diodes. The RD signal needs to generate a voltage so they "borrow" power from the TD signal on each respective side of the isolators. This siphoning off of TD current on the ST side did not leave enough current to drive the isolator photo diode. In this case it wasn't necessary to have the receive on the ST side so I removed the RD supply. The only connections between the two ports is optical, within the optical Isolators.

Author:  adiel [ Fri Nov 19, 2004 10:35 am GMT EthGMT ]
Post subject: 

Tom, here is a diagram of how mines is working perfect WITHOUT any modifications to the opto-isolator. The big difference is that I connected mines backwards to get the stronger TD signal from the PC to power the Opto-Isolator. My Telebyte 269 is right next to the inverter. I used a cat5e db9 to db25 cable I made to connect the inverter to the db25 on the opto isolator. On the other end, I ran about a 100foot cat 5e cable from my computer to the opto isolator and used a phone connector I got from Radio Shack to connect into the other end of the opto isolator. I also welded two strands from the cat5e to run the TD from the pc to the opto-isolator to give it it's juice. The final step is to set the opto-isolator to DTE. All my connections are welded. Here is a "shaky" picture of the instructions since I am no electrical engineer. :mrgreen:

Henry, the inverter has been working great, thanks again!

Image

Thanks,
Adiel

Author:  tomk [ Sat Nov 20, 2004 4:17 pm GMT EthGMT ]
Post subject: 

I never thought to leave off the pin 3 connection to the STXR (should have payed more attention to the Fishbowl manual):oops:. I followed the instructions that came with the isolator. That makes sense that having pin 3 disconnected would prevent loading of the STXR TD signal via the isolator's power suppy. Good job! I think the UPG works great and I love this data link feature.

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