Not sure how to use Open Collector Jack and Thetis settings...

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N9SSW
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Not sure how to use Open Collector Jack and Thetis settings...

Postby N9SSW » Thu Feb 09, 2023 6:18 am

Not sure how to use Open Collector Jack and Thetis settings...

Spent at least an hour trying to figure out the OC settings and get any kind of measurable result at the OC Jack on the back of my 8000DLE

have a cable plugged in to the 9 pin, have attempted to select\deselect a huge combination of checkboxes on both the OC Receive pins and the OC transmit pin select boxes in Thetis as well as the Tx Pin action and Ext PA control TX\RX checkboxes, cant seem to get ANY results measuring with an ohm meter for opens and shorts as well as the volt meter for any voltage changes between gnd and any of the pins.

I may just not understand the implementation... I typically understand open collector to mean that one of the OC input pins would likely be either pulled high or low with a pull up or pull down resistor (typically pull up to 5v and when the base of the OC transistor is biased the collector turns on and the 5v pull up is then shorded to gnd via the transistor emitter\collector. Do I have some misunderstanding of this or am I doing something wrong in Thetis. My goal would be to use two OC pins on the 8000 configured in a method to act as separate PTT lines that will feed two transverters PTT inputs which could in theory be be set to PTT\Gnd or PTT\5V config. Id be happy if I could get either method to work.

Maybe I just dont understand OC in regards to the DLE8000 and Thetis... I have been looking for days and I cant seem to find any real solid info on how to make use of these OC pins.

Anyone have any info or seen links to resources they might share. I am in the market to purchase possibly two Q5 transverters and an looking for a reliable way to PTT switch their built in PA's via their PTT input, while I am still using my single PTT jack on the 8000 DLE to switch my HF amplifier...

Nick
DE N9SSW
N9SSW
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby N9SSW » Thu Feb 09, 2023 6:31 am

BTW I did the same testing with PowerSDR OpenHP and get the same non-existent results....

I might just need a fresh education on Open Collector use... It appears I am likely missing something.

Nick
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DL2XY
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby DL2XY » Thu Feb 09, 2023 9:15 am

An OC is simply a switch towards ground if activated.
There is no intrinsic pull up.
If you want to switch inductive loads (Relay coil) it is mandantory to use the COM pin for freewheeling.

ULN200x.gif
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w9ac
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w9ac » Thu Feb 09, 2023 9:59 am

N9SSW wrote: cant seem to get ANY results measuring with an ohm meter for opens and shorts as well as the volt meter for any voltage changes between gnd and any of the pins... I may just not understand the implementation... I typically understand open collector to mean that one of the OC input pins would likely be either pulled high or low with a pull up or pull down resistor (typically pull up to 5v and when the base of the OC transistor is biased the collector turns on and the 5v pull up is then shorded to gnd via the transistor emitter\collector. Do I have some misunderstanding of this or am I doing something wrong in Thetis.
DE N9SSW

Nick,

I think your understanding of the OC matrix in Thetis is correct. When the appropriate check box is selected, the OC outputs are switched from a ULN2003AD High-Current Darlington Array.

https://tinyurl.com/fvjewz78

The Darlington collectors do not utilize pull-up, nor pull-down resistors. Each collector alone is routed to the rear panel jack and when activated, is pulled down very close circuit ground (typically 5-20 ohms), in effect making a switch closure albeit polarity sensitive. Being a Darlington output, two transistors are cascaded to offer high current transfer gain and very good base junction protection that isn't achieved with a common BJT transistor.

When testing for switch closure with a Darlington transistor, I don't use a DMM; a VOM provides much better measurement results. Mine is a Simpson 260 with 20,000 ohms/volt DC circuit loading. That low-impedance loading helps to see the Darlington switch to circuit ground. So, VOM positive lead on the OC output pin, black VOM lead to circuit ground. Use the VOM's RX1 scale.

The ULN2003AD is rated for a maximum current of 500 mA at 50V DC (derated based upon duty cycle). That's 12 watts of power. But that doesn't mean we should be switching devices near that extreme. Orion's circuit board has very narrow printed circuit paths; don't turn them into fuses.

Paul, W9AC
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w-u-2-o
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w-u-2-o » Thu Feb 09, 2023 3:08 pm

Perhaps a simpler answer might be helpful.

Connect a 10K ohm resistor (or similar, anything between 1K and 100K will do) between the OC output you want to test and +12VDC. Connect the positive lead of a voltmeter to that same OC output.

Assuming there are no checkmarks in the OC table for that pin/band combo, you will see 12V on the voltmeter. The pin is being pulled up to 12V by the resistor.

When you place a checkmark in the appropriate place in the table for that OC output pin and the current band, the transistor on that OC output will conduct current and the pin will be pulled down to ground. The voltmeter will now read 0V, or close to it.

You can use these outputs to control digital inputs on other equipment if the other equipment has internal pull-up's on those inputs. Otherwise you have to provide your own external pull-up resistors, to the appropriate voltage, of course.

You can use these output as low side switches for relay coils, being mindful of the max. current rating of the outputs per the datasheet, of course.
Joe
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby Joe » Thu Feb 09, 2023 3:24 pm

viewtopic.php?f=17&t=3692&hilit=WD5Y

I hope this helps a bit. I posted this quite some time ago. The actual software has been much improved by Richie for control. I use the OC for bcd inputs - amp band selection. I also attached a schematic “file”, that shows the hardware involved.

73’s
Joe
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w9ac
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w9ac » Thu Feb 09, 2023 3:28 pm

Then how about even simpler with no test gear?

From the OC pin, connect a 680 Ω resistor in series with a standard red LED, anode side to +12V. It's not a measurement, but it does indicate if the OC is functioning correctly.

Paul, W9AC
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w-u-2-o
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w-u-2-o » Thu Feb 09, 2023 3:37 pm

You're probably right, Paul! If there's a resistor laying around, then there might an LED, too!

Heck, if you didn't have anything at all, you could just buy some cheap automotive, 12V LED indicators off of Amazon, the kind with the built in resistor, and use those. Red lead to +12V, black lead to an OC pin.

Example: https://www.amazon.com/Warning-Light-Indicator-Pilot-Directional/dp/B07J6N96S7/
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w9ac
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w9ac » Thu Feb 09, 2023 3:50 pm

w-u-2-o wrote:You're probably right, Paul! If there's a resistor laying around, then there might an LED, too!

Heck, if you didn't have anything at all, you could just buy some cheap automotive, 12V LED indicators off of Amazon, the kind with the built in resistor, and use those. Red lead to +12V, black lead to an OC pin.

Example: https://www.amazon.com/Warning-Light-Indicator-Pilot-Directional/dp/B07J6N96S7/

Scott,

You've just given me an idea to make a test jig using 7 small LEDs with internal dropping resistors soldered on a DB-9 connector. Power it from a 9V battery.

Paul, W9AC
N9SSW
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby N9SSW » Thu Feb 09, 2023 4:04 pm

Thanks for the suggestions all... After reading Paul's reply above the LED idea also popped into my head. I typed up a fairly long reply that I thought I posted but seems to be lost at this point while all these other replies were being posted by all of the rest of you... I may have a 12V LED laying around already.. if not I can breadboard a standard LED hit it with 3.3V off my breadboard 3v rail and tie the grounds together and tie the LED to an OC pin and play with that.

The goal will be to use the OC pins as band specific PTT switching for Q5 Signal transverter(s)... hoping I can get a 2M and 70cm transverters connected and running on the 8000DLE. I already have my PTT jack on my 8000 connected to my HF amp.

I looked at Joes link and somehow I envision a db9 medusa in my future with the DB9 plugged into the radio and several RCA connections hangigng out as PTT1\2\3\4\etc lol

Nick
N9SSW
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby N9SSW » Thu Feb 09, 2023 4:24 pm



Thanks for the link... Funny thing is I ordered this one (a little higher quality metal can)

https://www.amazon.com/dp/B09W28BR6K?ps ... ct_details

and received it last night which is what allowed me to poke around for several hours last night with no results haha.

I started working on it around 8pm and after hundreds of tests and measurements of every possible combination I looked up at the clock and it was already 12:38am lmao time flies I guess... :)

Nick
K4IBC
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby K4IBC » Fri Feb 10, 2023 5:28 pm

w9ac wrote:
w-u-2-o wrote:You're probably right, Paul! If there's a resistor laying around, then there might an LED, too!

Heck, if you didn't have anything at all, you could just buy some cheap automotive, 12V LED indicators off of Amazon, the kind with the built in resistor, and use those. Red lead to +12V, black lead to an OC pin.

Example: https://www.amazon.com/Warning-Light-Indicator-Pilot-Directional/dp/B07J6N96S7/

Scott,

You've just given me an idea to make a test jig using 7 small LEDs with internal dropping resistors soldered on a DB-9 connector. Power it from a 9V battery.

Paul, W9AC


Why not use 12 volts? It's all over just about every shack out there and use lights like Scott suggested.
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w-u-2-o
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w-u-2-o » Fri Feb 10, 2023 7:16 pm

Not Paul, but I could see using a 9V battery or something like that if you wanted a gadget you could just plug into the OC port without having to connect up any other wires, just to do quick tests. You could even get a standard serial cable and have the gadget laying on the table in some easy to see location.
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w9ac
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Re: Not sure how to use Open Collector Jack and Thetis settings...

Postby w9ac » Sat Feb 11, 2023 2:29 pm

Scott's right. It's not a permanent fixture and only used long enough to test OC ports. A battery fastened to the jig is fine and would last the shelf life of the battery.

Paul, W9AC

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