Bachmann Online Forum

This one I did do a search on.....

Can the circuit boards in the Spectrum 4-6-0 and 2-8-0 be removed and hard wiired for DCC Operation? Perhaps this should not be within the process of troubleshooting a problem (which is want I'm thinking) but I just wanted clarification.

Thanks all,
Russ

Yes.  Rich can give you more information.
Gene

I removed the pc board on a Spectrum Richmond 4-4-0 and just solder spliced the decoder wires. I insulated each wire with 1/16" shrink tube. I needed to add a 1k resistor because the engine has an LED. I have an advantage as I have been an electronic tech for many years. Your mileage might vary.

Rich

Russ;
As a total proponent of the "KISS" philosophy and have done enough DCC installs to feel a bit competent,  I now remove all the boards that come with an engine, and do hard-wire.  There is no need for them in reality, if you are installing decoders, especially if you are going with sound-and a lot of guys are, given the advances in the technology and increasingly competitive pricing as of late.

When/if you do this, do double check your wiring-and I do mean check!   
The wiring is essentially two leads that are your feeders, two to the motor, and two (or more?) to lighting.  Use a reliable VOM (volt/ohm/ammeter) to assist you in this, have a good 35-watt soldering pencil; and if you do not know how to solder, you will learn-this is essential! Learn to do it well, and it will pay off on spades.  Heat-shrink tubing is available in quantity at reasonable cost at most electrical supply houses; Ideal Industries markets it.

I recommend Tony's trains anyway as both an info source and a parts supplier.  Tony has both himself, and his staff, that are very knowledgeable and up to date, plus generally willing to talk you through a problem/question.   Whichever way you choose to go, good luck.

RIch

Thanks for the repies.....

I have a Spectrum 2-8-0 (DCC) that ain't running, I mean it does nothing. (I have changed decoders, checked wiring the best I could) Once confirmed that the board could be removed, I thought I would attempt the task and see what I could learn. I have the tools and have hardwired decoders before. Didn't know about the resistor though......

Thanks again,
Russ,       

It sounds like it is time for the three ates:  isolate, locate, and eliminate.

THis is how it works:  Find the two motor leads and isolate them from any plugs, etc; attach a power source to them (like a 12 volt transformer by MRC); and run it up.  If noting happens, you have a problem with the motor or the connections; if the motor runs well, then your problem lies somewhere else-like connections.

This is why I rant and rave about direct wiring a decoder to the leads, rather than go through that block.   Every decoder I have ever seen comes with some sort of wiring diagram, and directions.  The less things in your path, the less things that can trip you up.

RIch

Rich,

Amen to that brother......

Russ,

I just woke up.....

Which wire (what color wire) do you install the 1k resistor?

Thanks

It makes no difference. Many like to use the cathode lead. I do.

Rich

Thanks Rich...

After all these years...gonna do this...just need a refresher...

Engine is Bachmann Spectrum HO 2-8-0: Has two pins...one pin has a red and black wire...the other pin has two yellows, one red and one black.

The question is...do I tie the two pin connector (Red and Black) to the corresponding tender pickup (either front or back) together then tie into Pins 8 (Red Right) and 4 (Black Left) ?

thanks

     

Quote from: russ daley on January 01, 2021, 05:14:03 PM
After all these years...gonna do this...just need a refresher...

Engine is Bachmann Spectrum HO 2-8-0: Has two pins...one pin has a red and black wire...the other pin has two yellows, one red and one black.

The question is...do I tie the two pin connector (Red and Black) to the corresponding tender pickup (either front or back) together then tie into Pins 8 (Red Right) and 4 (Black Left) ?

thanks

     

Now you are getting confusing. Do you mean the two pin and four pin plugs between the loco and tender? Please be more clear.

RFich

Darn....

Yes...I met to say the two plugs between the engine and tender. One plug two pins, one plug four pins...

Sorry,
Russ

It has been some years.
I remember the two pin were for DCC pickups from the loco.
The four pin, two for the motor and two for the headlight. All the wires were yellow.
I had to trace with ohm meter. Easy to do.
By the way, what looks like two green resistors are 4.5 micro Henry ferrite chokes. Zero resistance. No resistor has those kind traces. I have worked with components since 1955. I have an Inductance meter also.
I just cut the caps. Those components form a tuned circuit to satisfy the UK. Bachmann sells a lot of DCC locos, different type, on the other side of the Pond.

RIch

Thanks for the replies Rich...I found a nice TCS pictorial and with my multimeter was successful on the wiring and programming. Other issues surfaced like I must of dropped this baby sometime ago as I found some body damage and rod linkage damage. If others are reading this post...yes...you tie the engine rail pickup wires to the tender rail pickup wires and then tie into the correct decoder wire.   

Very good.
I have never found any issues with the circuit boards except when they get in the way of putting in a decoder and speaker like the 4-4-0 tender which is small.
I did add wipers so all the tender wheels have pick ups.

Rich

I read several post on circuit board removal and headlight bulb/LED replacements but remain a bit confused on whether I need to add the 1K resistor when removing the circuit board and direct wire to decoder. The Engine is a Spectrum 4-6-0, probably purchased 2004-2007 time frame. To be honest....I couldn't tell you if the front headlight is a bulb or LED. The rear backup light looks like a bulb. The parts list really doesn't define. I do know that when I direct wired the light to a DC transformer I get the "dim" clear light same as in DCC and not the assumed LED green light I see on other engines. I can live with the dim light but I want to avoid burning out the existing light whatever it may be.

So questions are....I know what a resistor does but what exactly will the 1K resistor do in this circuit? Why a 1K? Do I need a resistor in my hard wiring regardless if the light is a bulb or LED? 

thanks,     

Yes. The PC boards were labeled also in my steamers.

Rich

Thanks Rich....Install in Blue Common correct?

Never mind Rich...After some more research I think I got it down...thank you...next adventure is getting a double crossover to work...oh boy....

Well 1k for LED's are normal and 28mm for speakers are normal at least for me.
I have done reverse loops and crossovers but never a double.
Good luck. It has been many years.
Time's fun when you are having flies. I will be eighty in April.

Rich

Well Happy Coming Birthday.....I'm 66 and really don't get into the hobby until cold weather....had the best train season this year than I've had in many years...spent a great deal of time this year trying to get some engines to run, learning how...remembering...etc...

thanks for your contributions Rich....