1/2 off TCS CN decoders

[thomasjmdavis]

Well, it does make sense that the CN and CN-GP would be on sale. I think they had this same sale a few years ago- I picked up 4 then. Most of the locos that take them (the Atlas GP-7s and -9s) were revised in 2007 of thereabouts. The RS-1s were fairly recently produced with the "classic" frame, but other RS units were revised some while back. So, the demand for these decoders will have fallen off over the years. By now, most people who are going to go to the trouble to install these did so long ago.  I'm going to go through my loco list and see if I still need any.  While there are other options, my preference has always been to use the same decoder in locomotives that are likely to operate in the same consist, and I committed to the TCS on my GP and RS units when I opted for DCC several years ago.

[peteski]

I plan on getting a hot air rework station to replace the on board shunts with 1000 ohm SMD resistors and use wired 0402 LEDs for headlights. The rest of the wires will be replaced with ESU 36 AWG wire. This should allow these boards to be used in almost any engine without milling.

Daniel,  you don't need hot air station to do that.  I have a complete Pace rework system (with suction and hot air) and I very seldom use the hot air for components with 2 pads (like resistors or caps).  Especially resistors.  It is easy to add more solder on both ends, move the iron's tip alternating between them making sure the solder is melted on both sides, then just use the iront' stip to pus the resistor off the pads.  Hopefully you have a temperature controller iron (for this I set mine for 700 deg. F).

If you aren't sure you can do this, use the SMD unsoldering kit SMD1NL from Chipquik. Digikey part # SMD1NL-ND.  It contains a low temperature metal alloy which makes unsoldering SMD components a breeze.  I only bother using it for components with multiple leads in tight spaces where there is no space to move the unsoldered components off its pads.

@Joetrain59 discovered it and posted info back in 2019.  Here is a video demonstrating its usage: https://www.chipquik.com/store/product_info.php?products_id=220001

[peteski]

That's pretty good Sumner, but those nicely machined Aztek frames have not been available for quite some time.  It was a real loss to the N scale DCC community when Aztek closed shop.

[Sumner]

That's pretty good Sumner, but those nicely machined Aztek frames have not been available for quite some time.  It was a real loss to the N scale DCC community when Aztek closed shop.

Thanks and I guess I'm confused.....are you saying...



.... that the frame is an Azteck frame.  I've heard of them but always thought it was a stock Atlas frame.  It was one of the first locos I put a decoder in so not much experience then and still learning.  Move pictures of it and the install ( HERE )

Sumner

[peteski]

Yes, the valley milled on top and the side slots for routing motor wires were machined by Aztek.  It is not a stock shell.

Those shells were very helpful in early DCC conversions.  I've done bunch of them probably around 25 years ago using wired Digitrax decoders whcih were available at that time.

[Sumner]

Yes, the valley milled on top and the side slots for routing motor wires were machined by Aztek.  It is not a stock shell

OK I figured out now why you thought it was an Aztek frame.  I should of figured it out  .



I did the milling  .  Usually don't use the mill unless I have to.  Haven't crushed a frame yet but it is a good possibility that it might happen at some point.  I did have the picture above in the decoder install link.

Also I did make a frame holder that worked really well holding an Atlas GP7 and...



... have the print files up for anyone that might want to try it ( HERE )

at the bottom of that web page.  If someone prints it and finds it works with another frame please let me know and I'll pass that on.

Sumner

[peteski]

LOL Sumner!  The point of this thread was not to have to make any modifications to the frames!  And here you go milling your own.  I had no idea you did that on your own. Not fair!   

Funny how what you did looks exactly (or almost exactly) like what Aztec frames looked like. John C. (owner of Aztec) owned a machine shop.

[Sumner]

LOL Sumner!  The point of this thread was not to have to make any modifications to the frames!

I thought the point was to sell 1/2 price TCS decoders and give us something to talk about for a couple days 

Sumner

[C855B]

I thought the point was to sell 1/2 price TCS decoders and give us something to talk about for a couple days 

Ha! They've been at that price for several months. I feel badly for the shops who stocked them before the sale, because the direct sale price is either at or below what they were wholesaled for.

[daniel_leavitt2000]

Daniel,  you don't need hot air station to do that.  I have a complete Pace rework system (with suction and hot air) and I very seldom use the hot air for components with 2 pads (like resistors or caps).  Especially resistors.  It is easy to add more solder on both ends, move the iron's tip alternating between them making sure the solder is melted on both sides, then just use the iront' stip to pus the resistor off the pads.  Hopefully you have a temperature controller iron (for this I set mine for 700 deg. F).

If you aren't sure you can do this, use the SMD unsoldering kit SMDTA30 from Chipquik. Digikey part # SMDTA-30-ND.  It contains a low temperature metal alloy which makes unsoldering SMD components a breeze.  I only bother using it for components with multiple leads in tight spaces where there is no space to move the unsoldered components off its pads.

@Joetrain59 discovered it and posted info back in 2019.  Here is a video demonstrating its usage: https://www.chipquik.com/store/product_info.php?products_id=220001

This is sort of a project designed to learn a new skill than do it with my current equipment. The hot air rework station would work well at my job, and if I can get it to do small BGA packages, then it solves a lot of non-train related problems. The resistors here are a first step.

I have been adding new tools to my soldering kit - low temp solder/flux paste made for reworking BGA components. I'm experimenting with liquid flux too (I always used paste before). Results with a standard iron are encouraging.

That ESU decoder looks very promising. No doubt it is already equipped with the 36AWG wire ESU sells. If the functions are designed around LEDs, I'll probably use it. If not, the TCS CN and the NCE N12SR (with the shunts replaced) will probably work best for me.

[C855B]

...if the functions are designed around LEDs, I'll probably use it. ...

Not on the LokPilot 5 Nano - they put full voltage out there, but I forget offhand if it was common (-) or common (+). What I do know is it annoyed me greatly when I started converting BLI RSD-15s from the factory decoder, as the factory LEDs are reverse of this scheme. Adding resistors is trivial, but by the time everything was wired-up best it could be, I really had to cobble up a Frankenstein board. I have three more to do and the roundtuit involves drawing artwork for a custom board.

Read the docs carefully. You might find the only ESU decoders that support LEDs directly are the drop-ins for recent Atlas chassis.

[peteski]

I have been adding new tools to my soldering kit - low temp solder/flux paste made for reworking BGA components. I'm experimenting with liquid flux too (I always used paste before). Results with a standard iron are encouraging.

Solder paste is a mixture of paste flux and microscopic spheres of solder. During soldering the heated flux evaporates and the tiny solder spheres ball up into a solid drop of liquid solder.   I just can't visualize how you use liquid flux and standard iron to rework BGA devices.

[Sumner]

. I'm experimenting with liquid flux too (I always used paste before). Results with a standard iron are encouraging

I for building turnouts and my electrical projects I started with paste, switched to  GC Electronics liquid solder-flux and liked it better than the paste.  Then and I think it was on here was introduced to Superior No 30 liquid flux and love it.  All that I use now for building turnouts and any electrical project I'm on.  I use a small plastic craft bottle with a metal dispensing tip.  Crush the tip almost closed.  Easy to put a drop wherever I need it.

That ESU decoder looks very promising. No doubt it is already equipped with the 36AWG wire ESU sells. If the functions are designed around LEDs

Are you asking if the LED's are on the decoder or can it control them?  You need a resistor but lots of options controlling them.

Sumner

[daniel_leavitt2000]

Solder paste is a mixture of paste flux and microscopic spheres of solder. During soldering the heated flux evaporates and the tiny solder spheres ball up into a solid drop of liquid solder.   I just can't visualize how you use liquid flux and standard iron to rework BGA devices.

Standard iron with solder paste for normal soldering jobs. I'll be using an air iron for BGA work. I did not get the air iron yet as we are about to leave for vacation.

Are you asking if the LED's are on the decoder or can it control them?  You need a resistor but lots of options controlling them.

I want on-board resistors. I think it is the clutter that gets to me. A mess of wires, heat shrink, tape, resistors and LEDs drives me crazy.

[peteski]

Standard iron with solder paste for normal soldering jobs. I'll be using an air iron for BGA work. I did not get the air iron yet as we are about to leave for vacation.

Maybe our definitions are different for what Ball Grid Array (BGA) chips are.

To me BGA chips have solder pads on the inner surface, so you cant' touch those with a soldering iron. That is why hot air is needed to hieat and melt asolder at all the pads under the chip.

This is what I think of as a BGA chip.


And this is a basic BGA rework station.

I want on-board resistors. I think it is the clutter that gets to me. A mess of wires, heat shrink, tape, resistors and LEDs drives me crazy.

I share your disdain for rat's nests.  My solution is to make simple custom-made PC boards which hold resistors and LEDs, or act as junctions.  It is quite easy to make those PC boards.