Renato

Hello, the wire came off at the circuit end, long ago, probably because of an accidental collision. The controller had been used with open cover (it was installed on a sort of a wooden rack). The wire laid off was close to the printed circuit but there are many possible connections in the range of a coulpe centimetres. And no evidence of broken wire on the PCB. However I think I could find the solution (or A solution at least). I soldered the wire to the brush of the "regulator" pot, as you can see on the schematic attached below. When "Simulator" switch is in OFF position there is a sort of a direct feedback connection between the central point of the capacitor partitioner and the brush of the "regulator" pot which controls current to the base of the leftmost transistor. With the connection I made, "Simulator" switch ON intruduces a variable resistance in series to this feedback circuit, thus providing slower evolution of the operating point, so to say (My English probably sounds horrible, hope you can understand). I tested the circuit and it works fine. The 100 kOhm position of the pot is marked "Brake OFF" on the front panel and this way when turning the regulator pot upwards from zero the locomotive hums a bit (some pulse oscillation I think) and slowly picks up speed. If I turn the regulator pot down to zero the loco continues at same speed and slows down in a very long time (more than 15 s). When at zero speed it hums until I turn regulator pot to zero. I then turned regulator pot up again, let the loco catch speed and returned regulator pot to zero. After that I turned brake pot up towards the "FULL brake" position and the loco speed slowed down faster. The more brake rotation up, the faster deceleration. When loco is stopped if I turn brake back to zero it will start again, until I turn regulator down to zero or brake pot up again. And this works both in forward and reverse direction. THe only worry I have is that the humming at stop is quite noisy so probably there is a high current ripple. To be safe I turned the regulator quickly down after loco stopped. Here below the schematic with the wire connected (I also added wire color indication for my convenience). Maybe this is not the best fix, don't know, I will keep locomotives monitored for overheat. Thank you all for advice and support. Renato

DId not have time to try yet. Thank you John, I will look once more into my diagram And thank you Butler, If my attempt fails I will write to Gaugemaster Renato

thank you all for advice. Answering to suggestions in order: there is no frayed end on the pcb side unfortunately I will try to connect the wire to the positiver rail and report reults, thank you no the hole is or a bolt that holds the pcb in place on top of an isolator column Lifetime is remarkable but shipment cost from and to Italy probably is quite high. thank you all, I will report result of trial Renato

Gentlemen, while trying to find information in the internet on how to fix my old Gaugemaster P controller I found this topic and saw that some of you are keen on Gaugemaster and similar controller circuits. So I subscribed and posted a new topic "Repairing a Gaugemaster P - Help needed". Simply a disconnected wire prevents operation of inertia simulator and I don't know where to solder it back ! So I "reverse engineered" the circuit diagram and posted it showing the broken connection. Unfortunately noone replied to my post yet. This to recall your attention hoping somebody may help me. Sorry for leading you out of topic, and thanks for any help Renato

Hello, I am an Italian railway modeller and I need help to apply a simple fix to a Gaugemaster P controller bought back in the '80s in order to restore Inertia/brake simulator functionality. The controller works but Inertia/Brake simulator does not, most likely because of a broken wire solder. I am not keen enough with electronics and simply don't know where the wire should be reconnected. So I reverse-engineered the circuit diagram and ask some kind advice where to solder the wire. In the attachments you can see the controller data sheet, the controller open with visible interrupted wire and the circuit diagram Thanks for any advice, Renato