QSI 50 Class Stay Alive

A Eureka 50 Class will run well out of the box but we have found the addition of a stay alive will improve its running significantly.

All steam engines suffer from pickup issues much more than say a diesel locomotive, this is due to their long rigid wheelbase making tender pickup a necessity so where possible a stay alive is a must-have accessory.

Fortunately, the QSI decoder in the NSWGR Eureka 50 class has a capacitor for DC operation making the task fairly straightforward.

Begin by removing the two self tappers at the front and by sliding back and inserting a single edge blade at the rear lever the back end away.

Note: remember to disconnect the ladder from the tender deck using fine tweezers.

With the top in a safe place locate the factory capacitor at the front of the tender, remove and using a blade expose the wire by removing a small amount of the heat shrink. On this locomotive, the positive was red and the negative black but the grey stripe on the capacitor is always denoting the capacitors negative.

The next task was to remove the reed switch which is why this was pulled apart to start. If the reed switch falls under the influence of the speaker magnetics it will always be resetting and not allowing the locomotive to operate as intended.

With the stay alive installed it is time to reassemble the tender.

Test run the locomotive as shown on the linked video before closing the tender for a final test.

Place the stay alive across the tender under the decoder with the smooth side up. Reinstall the factory capacitor at the front in its original location and start to close up

This is a rats nest so a little jiggle is required but it will close.

Insert the lug into their slots at the rear, slide back to engage the tender body at the rear, then reinsert the two [2] self tappers at the front of the tender.

If it does not close repack and try again

There are separate blogs on setting the long address and undertaking a reset of the decoder on a programming track which will have to be done after removing the reed switch.

To view video showing operation with the stay alive installed on Rumble: Click here

21 pin Stay Alive

This blog covers wiring a stay alive to a 21 pin TCS decoder but is applicable to all decoder conforming to the 21 pin standard

TCS do not recommend soldering onto the decoder

Using the attached image solder the black [earth pin 20] and blue [positive pin 16] onto the pin of the adaptor board. When finished ensure that no balls or solder bridges are present as the SD card slot resets are close to these pins.

If the 12 volt comes into compact with the blue pin comes into contact with the SD card slot will send 12V to ground and will cause arcing/sparking that will destroy the decoder.

Use of Kapton tape across the pads is recommended.

Note: Do not use additional KeepAlive devices in parallel with the TCS motherboard.

ESU provide a basic adaptor board for this installation - click here