clickertyclack

Found this listed as a equivalent to the 2N6027 on RS. http://uk.rs-online.com/web/p/ujt-transistors/2508963555/?searchTerm=NTE6402&relevancy-data=636F3D3126696E3D4931384E53656172636847656E65726963266C753D656E266D6D3D6D61746368616C6C7061727469616C26706D3D5E2E2A2426706F3D31333326736E3D592673743D43415443485F414C4C5F44454641554C542673633D592677633D4E4F4E45267573743D4E544536343032267374613D4E54453634303226&dym=nte640 Hope of interest CC

And here is the amended version.( nobody noticed mistakes then?) CC

Briefly looked at one at an exhibition recently. They were having problems which they were obviously incapable of resolving with there jmri system. However to keep things moving they had a fall back of a analog contoller and loco to keep the public interested. I wasn't and moved on. CC

So here it is, in true engineering fashion, being on the back of a fag packet, 'my' Gaugemaster U controller.

Gentlemen. ORDER ORDER! What, you can't code ? , programming a pic is easier then soldering ! You need to get with the 21st century. Everything " is soft" now Everything is soft now except programming a pic which is hard? Maybe for a good few of us. It's s hobby , I've seen layouts with enough automation and computer control to manage the Apollo moon launch Oh yes and it is obvious to many exhibition goers that this aspect of the hobby is of more interest to the owners than the train set hey have 'built'.

Hi Crossland and apologies if my comments above were considered out of order. A decoder is far more sophisticated than any analog controller. Of course yes I agree . What I was trying to put across is that it is feasible and indeed posible to replicate this type of motor control without the DCC protocol, our tracks being the conductors like that of the connections from the decoder to the motor. Again the term analog these days seems to imply old and traditional forms of motion control and the hobyist's who use it are somewhat dinosaurs. Not so. We should not forget also that connected to the decoder is a DC motor. I have yet to come across a DCC one! CC

Hi Guys, Ok You are right Jim having looked at the circuit again. I have to confess I have no experience of using thristor circuits but from my limited knowledge dare I question the statement below? I would argue that it is the amplitude of the pulses which is effected. "it is the voltage pulses that get wider" Since the pulse can not get wider than the periodic time of the rectified ac pulse then your statement implies that they are narrower at lower speeds.Not Sure. Hi Crossland ( Andrew?) Wasted on me! Are you saying that it is not possible to build a controller that exhibits all the qualities of that on a DCC Decoder? I would have to argue that strongly. H bridge,auduino etc anyone? I have no wish for this discussion to turn into a DC ver DCC thing which is not what I envisaged. Yes I have seen poor control of loco's using DCC and you need go no further than view some of the video's presented here on RMWeb. My reasons for looking at analog controllers are simple. Hum, noise are a no no. Also for this project I need to input loco speed and other data to a pc and using boring old analog is somewhat easier and less involved than the DCC protocol for what I envisage. Think of JMRI Virtual Sound Decoder,this being something else I was involved with. Looking back I was ridiculed for suggesting that the speed slope of a DCC loco could be altered to better match that of the VSD sound file! Bit different now................. Cheers, Willy

Hi Jim, With respect know how both controllers work. The one I have just sorted some parts for uses fullwave rectification without smoothing. The difference between the 2 being that I vary the amplitude of the pulses and the feedback controller slices the pulses.I guess the feedback uses a cap to sample gaps in pulses of your controller. Bet there is no feedback at full speed though there being no gaps and the waveform would look little different to mine me thinks!? CC

Hi Jim, Many thanks for your comments .I hope you don't mind me explaining that it's not the feedback that causes the noise but the pulses. No. It's just that we tend to associate feedback controllers with PWM. The UF controller has both it uses the unsmoothed (no capacitors) 50 Hertz mains frequency to create the pulses which is doubled to 100 Hertz by using 'full wave rectification'. So basically the controller is slicing the pulses. Have to say I am quite impressed with your controller thougth. Should I dare say it..........It is a lot better than some DCC controllers I have seen. Though I am sure their owners would argue! As an observation, how do you believe not having a conductivity issue between wheel and track and also wheels to pickups effected the operation? The reason noise is an issue is that after some 5 yrs after building a 'diesel' DC sound system, thought I would have a go at steam one! Have to start at the controller. Think I have now sorted that. Just waiting for some components and will breadboard it. Skol CC

Gentlemen, Many thanks for your comments. I too found the Codar circuit but alas was a bit confused by the circuit wrt to inertia. Have been playing over the weeked and think I have come up with a suitable circuit. Silly thing is I know I have a GM U controller somewhere but can I find it? NO! It is of course somewhere safe. Jim. Having never used a feedback controller how do you find the hum or noise? Is it an issue? CC

Hi Guys, I am looking for a circuit diagram of a Gaugemaster U controller or indeed something similar. Now I know I had the above in my posession but can I find it anywhere? No. I am sure there are members who will scream 'copyright'. Pse dont. The circuit has ben widely used in many fields for the best part of 50yrs that I know of and would be out of copyright if such existed anyway. The circuit is basically a voltage follower with a darlington on the output to the track. The inertia/braking which is switchable, consisting of a charge on a cap the rate of which is varied via the simulator pot. I would probably put a BC107 on the front end of the darlington with its base on the speed pot and emiter on the output to give me an element of closed loop control. I have seen a circuit online in the past but alas can not find it now. Any pointers would be appreciated. CC

Hi Randall, Only just noticed your last post in this thread. As you know, I use a pc based sampler for my train sounds which got me thinking after reading yours above, if something similar would be available as an app for iphone/ipad. Came up with this which might just be what you are looking for. http://appcrawlr.com/ios/ipro-djsampler#authors-description I think it will give you more control over sounds and eliminate any audible gaps. Its free so worth a try. Clickertyclack

Charlie, Like others can not see any details online. Can you give us an idea of price of the EM units pls? cc

I could not agree more. However you assume that this discussion is with respect to DCC sound only. It is not. And lets not forget this topic is not in the DCC Sound section. If I can get a better sound quality with DCC than I can with my DC system then great. But whichever one is being used the method is the same in that bluetooth is utilised for its higher quality and far cheaper price than mainstream sound decoders and can be used in both dc/dcc indeed any system even clockwork! 'It is all well and good having a multitude of sounds for a home layout, no other sounds to compete with, but at an exhibition, perhaps baseboard fitted speakers have an advantage over loco fitted etc.' As I said, " Iv'e done it before. Youtube search OB1Fran " Pse take a look. I believe you and others reading may find it of interest. CC