Protosound was vulnerable to scrambled boards?

Is the beacon output always active?  Is it a flashing drive?  Does it power LED's or incandescent bulbs?

Thank you John!

As for the lights, I take it they are going to be DC, and if I understood correctly the markers are 3-6V (dependent on track voltage?) and the head/tail lamps are 1.5V?  Can I run LEDs off of them?

I'm going to have to try the LED's on a PS/1 module lights, because I don't believe you can.  The white LED's for headlights would require 3 volts and current limiting, that's more voltage than is available.

The markers apparently can be LED's.

If you're dead-set on LED's, there is a way to drive them from the 1.5V outputs, it would involve a small NPN transistor and a resistor or two for each bulb, and a source of DC voltage.  You might be able to get that from the PS/1 module, never actually looked.

Just hook the LED headlamp up to the 6v cab lighting output. Use a 150 ohm resistor in series. Or run a headlamp off track power. shown here

http://www.jcstudiosinc.com/BlogShowThread?id=619

Dale H

Dale, that would work for a light always on, but if I want it to come on and off with the direction, then the 1.5V outs would need to be used.

I didn't know that LEDs needed that much to work.  But then I am a mechanical engineer and not an electrical engineer for a reason...

So for you EEs or more electrically inclined guys, could you use the 1.5V outputs to run a relay that turns the LEDs on that are powered from track voltage?  I'm used to working on my own cars, so when I think relays, that's the size I think of, big, which would only fit in large tenders, like my SP Cab Forward, but not in any diesels.  Do they make small relays?

I don't know what cab lighting output Dale refers to, as there is no such output on the PS/1 boards.

Since the 1.5V is too low to light a white LED (presumable what we'd want for headlights), my suggestion is the transistor to switch the higher voltage for the LED. Yes, this takes more components, that's the price you pay for using 15 year old technology with modern lighting.

If you want to run a 1.5V relay, there happens to be such an animal, I have some that I bought for another purpose.  They are the TQ2SA-1.5V.  IMO, these are overkill for the task, a 10 cent transistor and a resistor does the job just as well for a lot less money, and a lot smaller footprint!

PS 1 has a separate board for the lighting,usually in front section of a diesel. . Half wave rectification with a diode and a 7806 regulator as I remember. Has an output for the 1.8 volt light headlamp and one for the cab lighting.

Dale H

that would be the bottom board for the lights...half the front for lights and back half for the cuppler..whick one is cab?..just wondering is mth is the same setup as the QSI...want to put a low led light in the breakman house on the tender for my Q2

Put 3 pair of diodes in series to the motor from the reverse board. That would give you about + or - 2 volts DC depending on direction. Wire the bulbs in series to the 2 ends of the diode string.  In series put a 1n4001 diode to the bulb. The lamp will light in one direction and not the other and receive about 1.5 volts DC

Here is a diode string inserted in the motor wiring as described.

http://www.jcstudiosinc.com/BlogShowThread?id=488

Dale H

White LED's require around 3 volts to light.  However, if they're not current limited, about a volt too much and POOF!  You really want to provide a more positive method.  Since the outputs are already present on the boards, and they are directional, it seems pretty silly not to use them.

The direction light connections are about 1.2V generated off a diode voltage difference.

John Yes the beacon is a LED and it flashes automatically.  The Beacon output and the Marker output are current limited.  I said 3-5V for the marker because MTH documentation says 3V but I have measured 5V.  Gets back to the use of series or parallel markers.   The key is it is current limited.

Dale for PS-1 diesels, the headlights are the 1.5V bulbs.  Others use a 6V regulator and there are some boards with the current limiting resistors installed to operate LED markers.  Need to look at the CV board to tell.  G

Right George, that's why I suggested the transistor to switch that voltage and provide sufficient voltage for the white LED's.  If you can tap some DC off the board somewhere, a couple of resistors and a transistor is all that would be required.  If DC voltage isn't available, a diode from track voltage will get the job done.  Screwing around with diodes on the motor just doesn't seem the way to do this task.

These boards have so many diodes, 2 different DC VR there are plenty of places to tap for extra lights.  G

It did look like there must be some DC floating around somewhere on them!

GGG radio shack doesnt have the chip puller....

PLCC Chip Puller

Looks like he has an offer to fix it.

thankyou gunner john..