Hammant and Morgan Commander controller

[Il Grifone]

My attempt to find patent number 1177775 came up with something about teeth. Perhaps someone else will have better luck?

Edited December 15, 2020 by Il Grifone
'up' got lost in cyberspace

[Bassettblowke]

With my  expertise in such matters I dread to think what I would turn up

[railroadbill]

On 12/12/2020 at 19:32, Bassettblowke said:

Been some very good information about H&M controllers. Having a closer look at the manul pages Bassettblowke posted , the manual states that the Commander has "impulse control" for better slow speed running.  The Clipper I've got is a variable resistance type. However, I've never noticed any discernible difference between the two in operation over many years with a variety of locos.

[Bassettblowke]

I also have never had any problems and have never been able to notice any difference between them. However that said I’ve never really been able to stretch them, all of my layouts being simple and uncomplicated with very little demand placed on the transformer and controller. It would be interesting to hear opinions/comparisons with more up to date offerings and whether this vintage stuff is still considered viable.

[tomparryharry]

I also have H&M units. They must be 40+ years old by now. Still serviceable. The idea for the mini drill is a good idea; it never occurred to me...

[Ben Alder]

My Duette - birthday present 1970, and powered many a teenage and adult layout - is also now on bench duties for drill, soldering iron and test track work. I recently dug out my two H&M 3000's and reinstated them as my layout controllers, switched in alongside Orbits, as some locos prefer one or the other, and the H&M's give better control than any other type I have tried over the years, which have been many.

 

[melmerby]

On 14/12/2020 at 14:44, 5050 said:

A transistorised controller with a centre off.  To me, that's a rare beast.  I would rather have that than a switch like on my Gaugemasters.

I made one of those many years ago built around a push pull circuit and split rail supply

I used a 10k wirewound pot as the controller and added a centre tap to it so that zero was zero.

[melmerby]

On 14/12/2020 at 15:49, Il Grifone said:

My attempt to find patent number 1177775 came up with something about teeth. Perhaps someone else will have better luck?

Searching in the Intellectual Property Office. (IPSUM)

When putting in GB1177775 just gets whirling balls and "please wait" forever (EDIT 30mins +)

N.B. you need GB in front of the number, else you might get US or others.

Edited December 15, 2020 by melmerby

[Il Grifone]

8 hours ago, melmerby said:

Searching in the Intellectual Property Office. (IPSUM)

When putting in GB1177775 just gets whirling balls and "please wait" forever (EDIT 30mins +)

N.B. you need GB in front of the number, else you might get US or others.

 

I tried that and their other alternatives, including looking under expired patents, but no train controllers....    I doubt that the circuit is all that complicated though.

 

I had no trouble looking up the original pre-war Trix Express patent some time  ago (German efficiency?).

[spamcan61]

Here ya go, agreed IPSUM is pants, hence I use Espacenet:-

 

https://worldwide.espacenet.com/searchResults?submitted=true&locale=en_EP&DB=EPODOC&ST=advanced&TI=&AB=&PN=GB1177775&AP=&PR=&PD=&PA=&IN=&CPC=&IC=&Submit=Search

 

You even get a circuit diagram :-)

Edited December 16, 2020 by spamcan61

[Il Grifone]

As I thought, nothing too complex, now I'll have a closer look (assuming the distaff side* doesn't find me something to do - menacing noises have been heard!)

 

* Wife and daughter....

 

EDIT

No transistor types are listed, but, given the date, VT1 is probably an OC35 and VT2 an OC71. Superior (and cheaper) silicon types are available.

EDIT 2

No other component values either.

Edited December 16, 2020 by Il Grifone

[melmerby]

It's a fairly simple circuit, not as complicated as I expected it would be.

Useful if you want to refurbish one.

IMHO there are better ways to do it these days.

 

[Adrian K]

On 11/12/2020 at 09:42, Il Grifone said:

The Electran seems to be a development of the Commander incorporating a delay (undoubtedly involving charging and discharging a capacitor) to give gentle acceleration and braking.

Unfortunately I have not been able to find any description of the innards of either unit on the 'net.

You're right about the capacitor(s) - here they are inside a later model Electran; I took the lid off to replace the mains cable.

[melmerby]

Looks like an AC124 (driver) & AD148 (power)

 

I would change that selenium bridge rectifier for a modern silicon bridge rectifier.

It's also good practice to change old electrolytic capacitors.

[cypherman]

Hi all,

I do not have the Commander, but I have 3 Duettes and a Clipper and have found them incredibly reliable as controllers. 

[simes]

I too have a selection of old H&M units and have been following this thread with interest.  I have replaced the innards of a failed Commander controller with the Roger Amos high-gain feedback controller design and found that this gives better control than the original H&M Commander circuit.  However I have now decided to take this further after realising that the resistance mats in these devices - and in the Electran pictured above - appear to be mounted on asbestos formers.  It should be possible to dispose of these mats and replace them with a modern potentiometer whilst keeping the original H&M control knob which cleverly combines on/off, reversing and speed control in the one control.  If or when I solve this I'll post again. 

 

Only the Powermaster and Safety Minor have no resistance mats inside.  With all the others, we need to be careful about asbestos - as well as the selenium rectifiers and the old mains cables.  These issues apart, I still enjoy using these old controllers and with more modern circuitry inside they can be much improved.

[simes]

For anyone else interested in retro-look controllers, I can now say that converting an H&M Clipper to a transistor controller works well (see my post above) .  I recently acquired an H&M Clipper as part of a job lot of equipment.  I didn't really want the Clipper, because I knew it was a variable resistance controller, but I thought it could be useful as a fixed 12V DC or 16V AC power supply.  However, after I converted a failed H&M Commander (which is how this thread started) by adding new components to make one of the Roger Amos designs, I became hooked on the idea of converting the Clipper too.  I removed the resistance mat and the selenium rectifier from the Clipper and replaced them with a transistor controller and diode rectifier.  This has revitalised the Clipper and made a really useful controller with charming retro looks and of course the H&M centre-off control.  There is enough space in the Clipper to fit almost any transistor controller circuit, but I like the Roger Amos high gain closed loop controller because it is easy to build and gives excellent control of all locos from my oldest (a Wrenn 2-6-4T) to newest (a Heljan DPU).  My late father was at school with Roger Amos, but that's beside the point.  For anyone else interested in converting an old centre-off resistance controller to a more modern circuit, the principal challenge is finding a centre-tapped potentiometer to act as the control device in place of the H&M resistance mat.  They are hard to find but Bourns still make them and mouser.co.uk supplies them (from the USA, but despite that they arrive quickly).  This one is the essential but hard-to-find component to make a centre-off version of most transistor controller circuits https://www.mouser.co.uk/ProductDetail/Bourns/PTT111-3220A-B503?qs=h2IHEVivlqCTVdtG16U05Q%3D%3D  .  My 'new Clipper' works so well that I have only one regret.  Ten years ago I threw out a working H&M Duette which I had owned since new because I thought I would never again want to use a resistance mat controller.  The Duette is in essence two Clippers in one case.  I could have converted that into two transistor controllers and it would have been all I need!

[Il Grifone]

I bought a control module on eBay with the intention of upgrading a defunct Hornby controller. Another of those jobs 'to do'. Having three HD Marshal IIIs doesn't make it urgent....

[simes]

I understand that.  The conversion job wasn't urgent for me either.  But once I had the idea it became a priority even though it wasn't strictly necessary!