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Jumper pins function Precision craft mother board

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Jumper pins function Precision craft mother board
Posted by old duff on Thursday, March 11, 2021 5:27 PM

What is the function of a pair of pins with a jumper on the mother board of a 2006 Precision craft models Bigboy? They are separate from the 8 and 21 pins. Does the jumper need to be removed when a decoder is added?

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Posted by SeeYou190 on Monday, March 15, 2021 1:40 PM

I do not know the answer, but I am replying to bump this thread to the top so hopefully someone with the answer will see it.

I think this thread was delayed over the weekend by moderation, and appeared "below the fold" when it was approved.

-Kevin

Wink Happily modeling my STRATTON & GILLETTE RAILROAD. A Class A line located in a personal fantasy world of semi-plausible nonsense on Tuesday, August 3rd, 1954.

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Posted by gmpullman on Monday, March 15, 2021 1:50 PM

Possibly a QSI decoder.

Those early models required adding a jumper to perform a total reset.

Later this was replaced by a reed switch and more recently with a rubbery push button.

I'll have to do a little digging to see exactly which version of QSI decoder you have.

https://www.broadway-limited.com/support/manuals/PCM%20Universal%20steam%20and%20diesel%20manual.pdf

 

 

 QSI reset jumper by Edmund, on Flickr

Good Luck, Ed

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Posted by rrinker on Monday, March 15, 2021 3:30 PM

PCM locos used ESU Loksound v3.5 decoders. That's why they came up with a differnet name - it's the same company as BLI. 

Neither of mine are accessible so I can see if the jumper is on or off with a decoder installed. 

All the manual says is that you can upgrade the DC model to DCC by simply plugging in a decoder. No mention is made of any jumper plug.

                                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Overmod on Tuesday, March 16, 2021 12:00 PM

Can the OP be a bit more specific and perhaps link a picture or two?

I got the impression from the post's wording that he did not think his locomotive had a decoder installed yet, in which case the jumper he observed would not be for reset.  The immediate thing that came to mind would be the 'correct' way to implement the kind of DC-to-DCC 'transition' that involves cutting traces on a P2K 'motherboard' -- instead you'd pull the jumper and leave it on only one pin, like the configuration jumpers on an IDE drive.  He noted the locomotive dated from 2006, which is certainly back in the primitive-QSI era... but I would be more comfortable knowing he actually is looking at a QSI decoder (or not...)

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Posted by gmpullman on Tuesday, March 16, 2021 12:21 PM

Scroll down in this TCS installation page for a look at what MAY be the board the OP is refering to.

https://tcsdcc.com/installation/ho-scale/2023

Without knowing exactly which version (stock number) of the PCM/BLI loco he is refering to we are just making best guess assumptions.

 BLI_UP-tender by Edmund, on Flickr

The motherboard here shows both an 8 pin and a 21 pin MTC socket. I was (erroneously) under the impression the 21 pin is a fairly recent innovation, certainly more recent than 2006. §

 BLI_UP-tender_board by Edmund, on Flickr

Both photos: TCS


 

The jumper in the OP's question MAY be the one near the capacitor? The motherboard is still a BLI/PCM design which your choice of decoder can be plugged in.

I don't find any reference to the jumper in any of the BLI/PCM documentation.

§ I stand corrected. Read HERE.

Regards, Ed

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Posted by rrinker on Tuesday, March 16, 2021 6:01 PM

 That should be it - that's a PCM tender with an ESU decoder. Looking at the picture, the jumper links 2 pins on the connector to the left. Guess the next step would be to trace where those 2 wires happen to go. If the TCS picture were a little clearer - I think the pins on that connector are labeled along the edge of the PCB at the very left. Unless that's just a board part number or something.

                                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by old duff on Monday, March 22, 2021 9:55 PM

This is the same mother board!!!  Maybe the jumper remains in place for an 8 pin decoder and is removed for the 21 pin decoder?? The picture shows the jumper removed with the 21 pin decoder.

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Posted by rrinker on Tuesday, March 23, 2021 10:13 AM

 I stills ay, look closely at the board and see which pins of that connector on the left the jumper connects to. That should provide some clue as to what it does.

                                   --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    August 2003
  • From: Collinwood, Ohio, USA
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Posted by gmpullman on Tuesday, March 23, 2021 1:30 PM

old duff
Maybe the jumper remains in place for an 8 pin decoder and is removed for the 21 pin decoder??

It couldn't hurt to send an email to BLI support and ask them.

http://bliservice.com/techsupport-options/

The people in the tech support dept. have always been helpful when I made a request.

Good Luck, Ed

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Posted by old duff on Thursday, April 1, 2021 9:47 PM

BLI tech support says the pins & jumper are only for reset! They had limited info otherwise. Sounds like sound decoder instalation instructions don't exist anymore!!

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