Decoders for Tortoises - cost effective when spread across baseboards.

[Norm81]

I’ve now got all the tortoises I need to convert my layout I need to think about control. My layout has the following:-

 

Board 1, 4 points configured as 2 crossovers.

Board 2, 5 points, 4 of which are configured as 2 crossovers.

Board 3, 2 points configured as 1 crossover,

 

I have an DCC Concepts alpha encoder etc for the control panel, and/or could use my NCE powercab.

 

I was looking at an NCE switch 8, as I found one channel could throw 2 points as a crossover so it had enough to drive everything. But, I’ll have almost as many inter-board connections as analogue control not just the accessory bus. It would be the cheapest option at about £70. If I put a switch 8 on boards 1&2, then a switch-it on board 3 it’s heading for £200.

 

Then I looked into Wabbit/Hare/Jack Wabbit, I would need a wabbit, a hare and two jack wabbits which again is heading for £200.

 

I found a single DCC concepts AD1-HP decoder I would need 11 of at £7 each but I have no idea if these are any good or not. They also do a 2/4/6 way AD-fx series ones which would be comparable in cost to a single NCE switch-8.

 

I’m looking for ideas on how to drive these without breaking the bank or having lots of inter-board connections. I’ve done a lot of reading, including on here, so have an idea what types are available but it might be I have missed some or there’s some feedback on the DCC Concepts decoders as the switch-8, hare, wabbit etc all seem to have a good reputation.

 

Thanks.

[Mick Bonwick]

I have employed DCC Concepts AD-fx decoders to drive a mix of Cobalts and Tortoises on my layout under construction. I have three pairs of points configured as crossovers and these decoders work them without any problems, so far, driving two points from each port. The availability of different port densities on one board allows the decoders to be placed nearer to the points they drive, which might help your board-to-board connection dilemma.

 

You could use DCC Concepts AD-fx distributed as follows:

 

Board 1 - 1 x 2-port AD2fx (£18)

Board 2 - 1 x 1-port AD1HP (£9) & 2 x 2-port AD2fx (£36)

Board 3 - 1 x 1-port AD1HP (£9)

 

I make that a total of £72.

 

I have used both Hare and Wabbit in the past, but they were a bit of overkill in my opinion, with all their connectivity options and control capabilities. All I wanted to do was change the direction of the trains.

Edited June 24, 2020 by Mick Bonwick
Can't add up.

[Phil Bullock]

There are many options .... another would be ESU switchpilots , 4 ports on each, £33 each so £66 if you accept cross board connections or £99 if you go for 1 per board.

[meil]

MERG DCC Accessory Decoder - £11 each

[tender]

The DCC Concepts AD1HP decoders can drive multiple Cobalts or Tortoises so assuming you would want your crossover pairs to switch together you would only need 5 AD1HP's. 5x£8=£40 (from a well known Liverpool outlet).

[pheaton]

I use a pair of signatrak dac20s, to control 16 tortoises, easy to setup had no issues  I was considering a switch8 but couldn't find any in the UK at the time.

 

on the other 12 tortoises I use Hares, but these are an expensive option, I just managed to get a bulk lot for a very good price.

 

Edited June 24, 2020 by pheaton

[Oldddudders]

Don't forget that any Tortoise-powered crossover needs only one decoder of any denomination. You simply use the reversing contacts on one Tortoise, which has the decoder, to drive the motor on the other one as a slave. This also has the advantage of making the two points move in sequence, rather than in sync, thus aping powered points in the prototype.

 

Presumably other brands of slow-motion point motor offer the same facility. 

[pheaton]

blimey....its alway obvious stuff you never think about  wish id thought of that earlier olddudders could have saved a bit of money...

[Norm81]

 

1 hour ago, Phil Bullock said:

There are many options .... another would be ESU switchpilots , 4 ports on each, £33 each so £66 if you accept cross board connections or £99 if you go for 1 per board.

 

Would I not also need the extension for each switchpilot to drive tortoises, as I think they can only drive solenoids direct?

 

33 minutes ago, tender said:

The DCC Concepts AD1HP decoders can drive multiple Cobalts or Tortoises so assuming you would want your crossover pairs to switch together you would only need 5 AD1HP's. 5x£8=£40 (from a well known Liverpool outlet).

 

I’ve got 5 crossovers then there is a single point (my OP could be clearer) so I’d need 6, but that’s still looking a good solution.

 

Thanks for all the replies, certainly some solutions I had not considered and the point (pun intended) about cascading one tortoise of a crossover from the other is good for saving a decoder and realistic operation too.

[melmerby]

31 minutes ago, Oldddudders said:

Don't forget that any Tortoise-powered crossover needs only one decoder of any denomination. You simply use the reversing contacts on one Tortoise, which has the decoder, to drive the motor on the other one as a slave. This also has the advantage of making the two points move in sequence, rather than in sync, thus aping powered points in the prototype.

 

Presumably other brands of slow-motion point motor offer the same facility. 

Which if you are using the switches to power frogs?......................

Don't say use a juicer because that is just more cost and extra wiring.

Edited June 24, 2020 by melmerby

[Nigelcliffe]

34 minutes ago, melmerby said:

1 hour ago, Oldddudders said:

Don't forget that any Tortoise-powered crossover needs only one decoder of any denomination. You simply use the reversing contacts on one Tortoise, which has the decoder, to drive the motor on the other one as a slave. This also has the advantage of making the two points move in sequence, rather than in sync, thus aping powered points in the prototype.

 

Which if you are using the switches to power frogs?......................

Don't say use a juicer because that is just more cost and extra wiring.

 

In most cases, you're OK with the contacts provided.  
In general, you need 1 SPDT for the frog.   On a cross-over, or a cross-over with a diamond following it, there are 2 SPDT's needed to deal with the frogs.  

 

Each Tortoise has 2 SPDT switches.   How they are used depends on the power supplies around ( a split DC, or half-wave AC, will save one contact set), but general case is:

 

Motor-1, controlled by decoder.  Use both contacts to reverse power to Motor-2.   On Motor-2, use one set of contacts for frog on Turnout-1, and the other set for frog on Turnout-2.  

The downside is the frogs won't be switched until both motors have completed movement.  

 

 

 

- Nigel

 

 

Edited June 24, 2020 by Nigelcliffe

[melmerby]

Gets a bit more complicated if you have a scissors crossing.

[Nigelcliffe]

5 hours ago, melmerby said:

Gets a bit more complicated if you have a scissors crossing.

 

More wiring, yes,  but still works using the method I outlined using just the contacts on one of the paired tortoises for each half of the scissors. 

 

Running rails coloured red/black to indicate which side of DCC bus to connect to those rails.  Frogs in bold need switching, in colours yellow, green, blue and mauve. 

 

Turnouts 1+2 work as a pair, turnout 1 on decoder, uses two contacts to operate turnout 2, and the two contacts on turnout 2 operate frogs Green (2 connections to same switch) and Blue (2 connections to same switch).  

Turnouts 3+4 work as a pair, turnout 3 on a decoder, uses two contacts to operate turnout 4, and the two contacts on turnout 4 operate frogs Yellow (1 connection to switch) and Mauve (1 connection to switch). 

 

Legal Paths: 

Both Straight, 

3+4 straight and 1+2 diagonal

3+4 diagonal and 1+2 straight.

 

As with any scissors switched (unless one uses frog juicers which switch on the short), there is an illegal path, which is both diagonals together.  In one direction that has short circuits.  In this specific example, if both diagonals are selected, then path 3 to 4 will be a short at the diamond.  

 

 

(Edit to diagram - I'd not coloured the lowest rail red, now corrected ). 

 

 

- Nigel

 

 

 

Edited June 24, 2020 by Nigelcliffe
diagram corrected

[melmerby]

30 minutes ago, Nigelcliffe said:

 

More wiring, yes,  but still works using the method I outlined using just the contacts on one of the paired tortoises for each half of the scissors. 

 

Running rails coloured red/black to indicate which side of DCC bus to connect to those rails.  Frogs in bold need switching, in colours yellow, green, blue and mauve. 

 

Turnouts 1+2 work as a pair, turnout 1 on decoder, uses two contacts to operate turnout 2, and the two contacts on turnout 2 operate frogs Green (2 connections to same switch) and Blue (2 connections to same switch).  

Turnouts 3+4 work as a pair, turnout 3 on a decoder, uses two contacts to operate turnout 4, and the two contacts on turnout 4 operate frogs Yellow (1 connection to switch) and Mauve (1 connection to switch). 

 

Legal Paths: 

Both Straight, 

3+4 straight and 1+2 diagonal

3+4 diagonal and 1+2 straight.

 

As with any scissors switched (unless one uses frog juicers which switch on the short), there is an illegal path, which is both diagonals together.  In one direction that has short circuits.  In this specific example, if both diagonals are selected, then path 3 to 4 will be a short at the diamond. 

 

 

- Nigel

 

 

 

I'll have to revisit my wiring as I ended up using two switches on different torti to switch one route as there was a short otherwise (bit of "and" logic)

[Nigelcliffe]

28 minutes ago, melmerby said:

I'll have to revisit my wiring as I ended up using two switches on different torti to switch one route as there was a short otherwise (bit of "and" logic)

 

There will be other solutions to the scissors crossing, my illustration was only one solution. 

 

 

[Andy Reichert]

1 hour ago, Nigelcliffe said:

 

There will be other solutions to the scissors crossing, my illustration was only one solution. 

 

 

 

Yes. The rail triangle formed by the upper three frogs and the mirror image triangle of the lower 3 three frogs can each be a complete switched unit, switched by turnout 1 and 3 respectively.

 

If operated as two independent crossovers, then I think the two centre frogs (LH and RH diamond ends) can be separately switched by turnouts 2 and  4.  

Edited June 24, 2020 by Andy Reichert
correction of turnout number

[Graham Radish]

The next time i fit point motors they will be the tortoise types, my cobalt digital ip's are a no fuss "built in decoder" luxury, however the noise is unbearable to me, not excessively loud but loud enough to ruin automated running sessions, im sure the techs over at dcc concepts will cure this problem in their later product lines, but as it stands i regret fitting them really, i'd take a bit of extra wiring over the noise any day.

[melmerby]

1 hour ago, Graham Radish said:

The next time i fit point motors they will be the tortoise types, my cobalt digital ip's are a no fuss "built in decoder" luxury, however the noise is unbearable to me, not excessively loud but loud enough to ruin automated running sessions, im sure the techs over at dcc concepts will cure this problem in their later product lines, but as it stands i regret fitting them really, i'd take a bit of extra wiring over the noise any day.

It's was there at the start.

The only two Cobalts I ever bought were considerably noisier than Tortoises and that was the "original" type from years ago, so I wouldn't hold your breath!

 

[WIMorrison]

Look at MTB MP1 or MP5 motors, easy to switch, very easy to adjust and virtually silent.