Installing Bachmann 1 amp decoder into a new Bachmann B23-7 Locomotive

[Hueydr]

The Bachmann B23-7 comes with front and rear LED lights on a long circuit board H11105, (PCB with light bulbs and diodes).  My question is were to connect the white, yellow and blue wires to controll the lights? Do I have to ditch these lights and buy new LED lights with resistor?

Thanks ahead of time if anyone can help me.

Hueydr

[richg]

If it has diodes, I suspect a DCC ready loco or the diodes are for constant lighting on a DC layout.
Does the loco have a pancake motor or can motor?
If pancake motor, the motor connections would have to be isolated and the motor and pickups might not be the best or even adequate.
A photo would sure help in solving issues like this. A picture is worth  thousand words.

Does this PC board have any tabs on it that are numbered, 1 though 8? If it does, remove the clips and solder the wires to those tabs. I say that, because a few Bachmann diesels have that setup. I could not find a diagram for the loco to determine what it looks like inside.
If it is strictly a DC only loco, you will have to rewire and use resistors for the lights. Many us a 1k, ¼ watt resistor in series with the yellow and white wires.
The blue goes to the other pin for each LED.
Looking at the PC board, there might be an indicator for which lead is positive and negative.
The yellow and white wires are negative.
The blue is positive.

The decoder info should be with the decoer.
I figure you know how to solder.

Rich

[Hueydr]

Rich, I have taken some pictures for you to see the LED's on the board. I know how to hookup the motor wires and rail wires, just need to know what I should do about the LED's (where to solder the white, yellow and blue from the decoder.
Thanks again for your help.

Vic

[jward]

i believe the b23-7 was originally released as a spectrum loco. as such there would be no pancake motored versions.

the b23-7 i have is similar in construction to the gp40. as such, it is not an easy conversion to dcc, but not hard either. the motor has tabs which connect to the frame and circuit board. those will have to be removed, and the motor isolated.

why buy new led's with resistors when with a little care you can solder the resistors to the led's yourself.

also, be certain that what you have are led's and not bulbs. led's will read low ohms one direction, high ohms the other, when measured with a meter.

[richg]

i believe the b23-7 was originally released as a spectrum loco. as such there would be no pancake motored versions.

the b23-7 i have is similar in construction to the gp40. as such, it is not an easy conversion to dcc, but not hard either. the motor has tabs which connect to the frame and circuit board. those will have to be removed, and the motor isolated.

why buy new led's with resistors when with a little care you can solder the resistors to the led's yourself.

also, be certain that what you have are led's and not bulbs. led's will read low ohms one direction, high ohms the other, when measured with a meter.

I have used LED's for some years. None ever showed any resistance. All you see is the equivalent of an open circuit. I use a ohm meter with the 200k scale and nothing.
Yes, I used 12 vdc with a 1k resistor and the LED's work.
Standard diodes do show the Resistance.

I would be interested in knowing which LED's you have that show resistance.

Rich

[Hueydr]

Rich,
I cut the LED's from the board and picked up some 1/4 watt 1K resistors and installed just like you said - worked fine.  Thanks so much for your help.  Now I can install LED's in the rest of my loco's

Hueydr (Vic)

[richg]

Rich,
I cut the LED's from the board and picked up some 1/4 watt 1K resistors and installed just like you said - worked fine.  Thanks so much for your help.  Now I can install LED's in the rest of my loco's

Hueydr (Vic)

It is nice when a plan comes together. Good news.

For those who do not know how to search the 'Net, below is a good link on LED's/bulbs used in DCC. There are hundreds more links available in searches but this should be enough for most here.

https://sites.google.com/site/markgurries/home/part-sources/led-s/resistors-for-leds-bulbs

Matk has tons of usefull DCC info. People, take time to store the link in your PC browser and do a lot of reading.

Rich

[jward]

I have used LED's for some years. None ever showed any resistance. All you see is the equivalent of an open circuit. I use a ohm meter with the 200k scale and nothing.
Yes, I used 12 vdc with a 1k resistor and the LED's work.
Standard diodes do show the Resistance.

I would be interested in knowing which LED's you have that show resistance.

Rich

the open circuit is, by definition, high resistance. when you measure an open circuit with an ohmmeter, you will get the highest resistance reading possible.

the point is, resistance should be very low in one direction, and infinite the other direction. if it reads low both directions you probably have a light bulb. if it is high both directions, you have a burned out component.

[richg]

I have used LED's for some years. None ever showed any resistance. All you see is the equivalent of an open circuit. I use a ohm meter with the 200k scale and nothing.
Yes, I used 12 vdc with a 1k resistor and the LED's work.
Standard diodes do show the Resistance.

I would be interested in knowing which LED's you have that show resistance.

Rich

the open circuit is, by definition, high resistance. when you measure an open circuit with an ohmmeter, you will get the highest resistance reading possible.

the point is, resistance should be very low in one direction, and infinite the other direction. if it reads low both directions you probably have a light bulb. if it is high both directions, you have a burned out component.

Yes, I agree, maximum resistance.
A LED, Light Emitting Diode will have max ohms, either way. Not measurable with the regular meters we use.
A standard diode, high one way, low the other way.
A ohm meter with the probes laying on the workbench will usually show something on the on the display, but not an actual number. The same as when connected to an LED, either way. Newbie's generally do not under stand this because they do not see an actual number.

That is why the occasional person gets confused when they hold the probe tips and LED with their finger tips and see a ohm reading if the meter is say on a 200k or higher resistance scale or they have an auto ranging ohm meter. They are not aware they are seeing their body resistance.

I first realized that back around 1956.

All LED's I have seen that burned out, have maximum resistance but newbie's do not understand this. They see no light and no current flow and figure the LED is bad. Most have a 9 volt battery laying around and maybe a 1k resistor.

Rich