Homemade Gaugemaster U Controller

[clickertyclack]

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

 

 

[dhjgreen]

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

Model W here if any use.

http://www.rmweb.co.uk/community/index.php?/topic/57463-gaugemaster-model-w/?p=711999

[Tim V]

I have a Codar controller sat in the garage, performance was pretty rough, fine for X04 type motors.

 

that had an additional inertia setup, can't remember what that looked like now. Probably 40 and more years ago.

[clickertyclack]

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

[clickertyclack]

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

[bertiedog]

The Codar Company were an Amateur Radio Enthusiast company that branched off into Model Railways controllers and power supplies in the mid 1970's. The circuit published is the main product that they did at the time. They also used the same circuit without a meter fitted, and a duel model.

 

Stephen

Edited September 23, 2017 by bertiedog

[clickertyclack]

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

[Pannier Tank]

The Codar Company where an Amateur Radio Enthusiast Company

 

They were indeed and produced some reasonable Radio Transmitter / Receivers, still very much sought after.

[Crosland]

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.

If you are talking aesthetics, than that is subjective.

 

With DCC the control in on the loco. A decoder is far more sophisticated than any analog controller. There are very few cases were analog control will produce better results than even a basic decoder, once the decoder is setup correctly.

 

Some analog controllers have attempted to include tuning for various motor types but will always result in compromises when used across a fleet of locos.

[clickertyclack]

Hi Guys,

 

 

Hello CC,

 

May I ask you to look at the UF circuit again and see that there..........................

 

 

 

 

 

 

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?

 

 

............ it is the voltage pulses that get wider as the speed increases ending up when they meet with pure DC at full speed.

 

Cheers - Jim

 

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?)

 

 

If you are talking aesthetics, than that is subjective.

 

 

 

Wasted on me!

 

 

 

A decoder is far more sophisticated than any analog controller. There are very few cases were analog control will produce better results than even a basic decoder, once the decoder is setup correctly.

 

 

  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

[Crosland]

 

Hello CC,

 

You will often see the term PWM = Pulse Width Modulation, the wider the pulse the higher the speed

In a controller with no feedback the amplitude remains the same

 

With feedback the amplitude is varied

The effect of feedback can be seen in the Oscilloscope image for the Hornby R965 controller on the scottpages controller review: http://www.scottpages.net/ReviewOfControllers.html

 

Pulse width controls the speed, amperage controls the power.

 

Cheers - Jim

 

 

There are many ways to skin a cat and feedback can influence any parameter, frequency, pulse width, amplitude, as chosen by the designer. DCC decoders that have feedback vary the pulse width.

 

Pulse width is not limited to the rectifed 50 Hz. A controller can generate it's own time base and independent of the mains.

[Crosland]

 

Pulse width controls the speed, amperage controls the power.

 

Not sure what you are trying to get at there. Power is the product of voltage and current. Increasing the pulse width increases the average voltage and will deliver more power subject to a given current limit.

[kevinlms]

If you are talking aesthetics, than that is subjective.

 

With DCC the control in on the loco. A decoder is far more sophisticated than any analog controller. There are very few cases were analog control will produce better results than even a basic decoder, once the decoder is setup correctly.

 

Some analog controllers have attempted to include tuning for various motor types but will always result in compromises when used across a fleet of locos.

Agreed, a DCC decoder can be individually configured to suit the characteristics of a particular model - depending on model of decoder & whether or not the master controller supports all the features.

 

A DC controller, unless quite complicated with adjustable resistances & even capacitance, will be best suited to particular types of motor. That's why many are not recommended for use with Portescap type motors.

[clickertyclack]

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

[Crosland]

Hi Crossland and apologies if my comments above were considered out of order.

 

Not at all

 

Andrew

[Junctionmad]

MERG www.merg.co.uk has some good circuits for DC controllers, including pulse width and feedback types . you need to join to get access to the relevant Technical Bulletins , all are reasonably modern designs too 

[Crosland]

MERG www.merg.co.uk has some good circuits for DC controllers, including pulse width and feedback types . you need to join to get access to the relevant Technical Bulletins , all are reasonably modern designs too 

 

There are some on the public site, no need to join https://www.merg.org.uk/merg_resources/other.php

[Junctionmad]

 

Hello JM,

 

Just my personal opinion this; modern electronic designs are often very complex and inferior to minimalist designs. Tne first time I heard a 300B single ended valve amplifier was a life changing experience all 3 Watts of it and then its 1950's transistor equivalent the John Linsley Hood 10 Watt, both have a huge worldwide following on DIY audio. 

 

Photography is the same with photographers using 4 and 6 element lens designs direct descendents of the  Cooke's of Leicester triplet (4 elements in a group of 3) designed in the 1890's. The Oscar winning company still make lenses for video and film movie cameras and those Cooke triplets for large format still cameras.

 

Here's one of Jonathan Scott's model railway modern pulsed feedback analog designs using a programmable PID controller.

 

He's an electronic expert and well he would design something like this wouldn't he.

 

But what does he use on his layouts, why bless my soul this the GM 'UF' :-)

 

Why? Because it's ridiculously easy to build, will go into the tiniest space and performs better than the PID controller and costs about £15.

 

The drawing is mine shows the 2 modified components for those who know how to solder I have done a PDF with explanations and instructions, a nice message and an email address and a copy is yours.

 

Cheers - Jim

 

[edit] speeling

 

 

 

 

Actually Heres what Jonathan Scott says about the Gaugemaster U circuit 

 

 

It works quite well, but it requires AC, or at worst unfiltered dc input, and so is not useful with batteries, etc. It is also a very dated design; it is like the old SCR or TRIAC-based power tool speed regulators that appeared in the late 1970s, but has a little gain provided by the BJT to sharpen the control, and give better low-speed regulation.

Needless to say, these things sell for a whole lot more than it costs to make them, including getting PCBs.

"Note " quite" prefix to the "  well" and " dated " , in fact most of the active components are obsolete , and all in all its a very simple SCR  controller 

 

and he actually replaced it 

 

 

 

I decided I wanted the same sharp speed control action, but I needed the contoller to work with battery supplies as well as AC. My design appears below. It has the advantage that it can be used with either AC, or unfiltered DC or filtered DC.

 

and seriously dude, I cant let this  one fly 

 

 

 

modern electronic designs are often very complex and inferior to minimalist designs.

crap designs, old or new, are just that, crap, being old or " minimalist " isnt any guarantee its better.

 

(in fact his PIC controller is actually extremely simple, and I suspect is designed so that the walk around controller can be removed and repositioned without the train stopping , i.e.  the PIC remembers the settings,  try doing all that with a few Valves , huh ) 

Edited September 21, 2017 by Junctionmad

[Pannier Tank]

 try doing all that with a few Valves , huh ) 

 

Now there's a thought, having worked on Valve Equipment for the last 40+ Years. Use  a 2D21 Thyratron instead of the SCR!

[bertiedog]

Now there's a thought, having worked on Valve Equipment for the last 40+ Years. Use  a 2D21 Thyratron instead of the SCR!

Many thanks, looking forward to the publication of a valve based controller based on your design, will it brew the coffee as well?....only kidding.......would help heat the railway room.....anybody for a DCC valve based controller?

Stephen

[SHMD]

Now there's a thought.

 

How about a clockwork DCC controller?

Think of a cross between a German Enigma cipher machine and a Rolla-Controller but powered by a big Main Spring!

 

    

 

 

Kev.

[Pannier Tank]

Many thanks, looking forward to the publication of a valve based controller based on your design, will it brew the coffee as well?....

 

Well the 2D21 Heaters do get quite warm but I think it would take a while to boil the kettle! Some of my old valve equipment had Filaments 6.6V @ 100A (10kW Equipment) we went up to 100kW Water Cooled  

 

https://www.e2v.com/resources/account/download-datasheet/128 

 

https://www.e2v.com/resources/account/download-datasheet/227

[bertiedog]

Well, dug through the storage boxes and with that and a couple of ordered items two of the controllers to the "dated" SCR type will be built in the next few days, about £10 worth for two, (I always order/find a few spares anyway) As usual, the cases will cost more than the electronics these days...Ohh... for the days of Edgware Rd and Lisle street electrical discount junk shops! Decent Ex services cases for penny's......

 

It's not as much fun on Ebay as digging through Smiths stockpiles to find military grade equipment like panel boxes for TSR2's !!! or panels from Bluestreak! If you found anything cheap and interesting you usually had to fight off Derek Meddings from Pinewood Studios, or the Gerry Anderson crew making the sets for the latest TV puppet productions! To rub salt in the wounds you can still see the good items they bought in the old shows!

Stephen

Edited September 21, 2017 by bertiedog

[AndyID]

Actually Heres what Jonathan Scott says about the Gaugemaster U circuit 

 

"Note " quite" prefix to the "  well" and " dated " , in fact most of the active components are obsolete , and all in all its a very simple SCR  controller 

 

and he actually replaced it 

 

 

and seriously dude, I cant let this  one fly 

 

crap designs, old or new, are just that, crap, being old or " minimalist " isnt any guarantee its better.

 

(in fact his PIC controller is actually extremely simple, and I suspect is designed so that the walk around controller can be removed and repositioned without the train stopping , i.e.  the PIC remembers the settings,  try doing all that with a few Valves , huh ) 

 

Except that, Dude, you are completely ignoring the many lines of code in the PIC. Who supports it if there is a bug?

 

It's a hobby. I'm all in favour of people using the lowest-tech solution that meets their needs.

[Junctionmad]

Except that, Dude, you are completely ignoring the many lines of code in the PIC. Who supports it if there is a bug?

 

It's a hobby. I'm all in favour of people using the lowest-tech solution that meets their needs.

What, you can't code ? , programming a pic is easier then soldering ! You need to get with the 21st century. Everything " is soft" now :D Edited September 22, 2017 by Junctionmad