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What is this thing on my GP7 chassis?

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  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
What is this thing on my GP7 chassis?
Posted by SeeYou190 on Friday, May 4, 2018 4:37 PM

I finally bought a "new old stock" Proto 2000 GP7, passenger version, with torpedo tubes that I have been wanting for a while.

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It had cracked gears which I just replaced with Athearn 60024 gears. That went pretty easily. None of my other three Proto GP locomotives had cracked gears, but I already had replacements on hand just in case.

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There is a circuit board on this one that my other Proto GP locomotives do not have. It does not say DCC anywhere on the box.

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Is this a DCC decoder?

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I hope not. It runs on DC, but it has a higher starting voltage than the others, so I am not sure. This one is at least ten years newer than my other ones. I am pretty sure the other three are Life-Like models.

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Can anyone verify whether or not this is a DCC decoder?

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-Kevin

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Living the dream.

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Friday, May 4, 2018 5:21 PM

You aren't much into close ups are you?   Wink

It sure looks like a 8 pin board, but maybe it goes with those 8 capacitors?  It looks nothing like my LL GP9 DC board.   Actually it does look like Mel's board in this thread.  My read is he did not consider it DCC ready.

http://cs.trains.com/mrr/f/744/t/258413.aspx

 
 

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
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  • From: Southern Florida Gulf Coast
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Posted by SeeYou190 on Friday, May 4, 2018 5:32 PM

BigDaddy
You aren't much into close ups are you?

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As requested... one close-up image. You can click on the image for a larger view.

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-Kevin

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Living the dream.

  • Member since
    January 2009
  • From: Maryland
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Posted by ATLANTIC CENTRAL on Friday, May 4, 2018 5:46 PM

That is simply the constant directional lighting and the interface for the 8 pin socket. Your loco is DC.

The higher starting voltage is because of all those diodes used for that 1.5 volt incandesent lighting circuit.

I take those out use a simpler circuit with LED's.

I have about 15 GP7's of that vintage, great locos.

Sheldon

    

  • Member since
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  • From: Shenandoah Valley
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Posted by BigDaddy on Friday, May 4, 2018 6:05 PM

ATLANTIC CENTRAL
I have about 15 GP7's of that vintage, great locos.

Not sure why, because I have enough other future conversions but I am watching Ebay auctions and a B&O GP9 had no bids at $40 and there is another one with what sounds like the broken gears with a high bid of <$22  There was also someone selling WM Proto geeps a couple weeks ago at a good price.

Totally satisfied with my GP conversion, with sound and grab irons in the above thread.  Because of an impending move, I did not install MU hoses or side rails.  They look pretty fragile.

 

 

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, May 4, 2018 10:40 PM

ATLANTIC CENTRAL
That is simply the constant directional lighting and the interface for the 8 pin socket. Your loco is DC. The higher starting voltage is because of all those diodes used for that 1.5 volt incandesent lighting circuit. I take those out use a simpler circuit with LED's.

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Thank you. That puts my mind at ease.

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I am not going to do any conversion. This locomotive will run alone, so the mis-match to the other three will not be an issue. Its duty will be to relieve the USRA 4-6-2 on the mail train. That train is only 4 cars long.

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-Kevin

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Living the dream.

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Saturday, May 5, 2018 3:59 PM

Yes, it's DCC ready. Digitrax has a decoder that does noto require the light bulbs to be replaced, the DH165L0. All of mine are of that style, I removed the boards and repalced the bulbs with LEDs and just hward wired the decoders in - the wires are colored per the proper color code. Yoou may have to reverse the orange and grey if you want to run long hood forward, connecting orange to orange and grey to grey runs short hood forward.

                                       --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
    December 2004
  • From: Pa.
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Posted by DigitalGriffin on Monday, May 7, 2018 11:46 AM

DCC ready, but no DCC installed.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

  • Member since
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Posted by ATLANTIC CENTRAL on Monday, May 7, 2018 2:59 PM

DigitalGriffin

DCC ready, but no DCC installed.

 

And since the OP said he does NOT want DCC, how perfect.

Sheldon

    

  • Member since
    February 2008
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Posted by maxman on Monday, May 7, 2018 4:22 PM

DigitalGriffin
DCC ready, but no DCC installed.

Just to educate myself.............but is it really DCC ready?  I enlarged the picture and don't see any holes in that board for an 8-pin to plug in.  All the "holes" appear to be filled with solder.

Does that entire piece get pulled out?  And what are the eight attaches black things?

Thanks

  • Member since
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Posted by wjstix on Monday, May 7, 2018 4:43 PM

"DCC Ready" means pretty much whatever that particular manufacturer using the term wants it to mean. It can mean there's a DCC-receptacle ready for a decoder, or that the motor is isolated from the frame, or just that there's (probably) room for a decoder in the engine.

Lightboards came in about the same time as DCC, so most likely if an engine has a lightboard, the engine is isolated from the frame - which is necessary for DCC. If the engine is "plug-and-play", the lightboard will have a receptacle for a decoder (usually for an eight-pin connection, though some have an eight and a nine-pin receptacle, and now some have an eight-pin and a 21-pin). If there is no receptacle, you would need to remove the lightboard and replace it with a "lightboard replacement" decoder, which looks like the lightboard and fits in the same location; or you'd need to do a "hardwire" installation and solder connections from the motor, wheel pickups etc. to the decoder harness wires.

Stix
  • Member since
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  • From: Maryland
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Posted by ATLANTIC CENTRAL on Monday, May 7, 2018 4:57 PM

maxman

 

 
DigitalGriffin
DCC ready, but no DCC installed.

 

Just to educate myself.............but is it really DCC ready?  I enlarged the picture and don't see any holes in that board for an 8-pin to plug in.  All the "holes" appear to be filled with solder.

Does that entire piece get pulled out?  And what are the eight attaches black things?

Thanks

 

Yes, that is a jumper plug that comes out, then the decoder plugs right in.

But that is not necessarily the "best" way to convert that loco to DCC.

Sheldon

    

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Monday, May 7, 2018 6:53 PM

 The part with the black caps, where all the wires attach, pulls out of that board with the directional/constnat lightign diodes on it, and it plugs in to the decoder. It's a 'backwards' setup where the loco has the male part, so there are only a few decoders that actually just plug right in, if you look at the Digitrax DH165L0 I mentiooned, the decoder looks like the bogger board with the diodes on it, and has an 8 pin SOCKET, the little wiring board plugs in to that. Most locos, the board on the loco has a socket and the decoders plug in to that.

 Just remove it all, hard wire a decoder, and ditch the light bulbs. Not difficult at all, and if you use one of the infinite variety of decoders that has a 9 pin connector, you can still pop out the decoder and replace it at some future time.  And the result is a neater looking job.

                                    --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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