[Gary]

A decoder is a decoder - is it?

Given that there is a standard and given that there is such an alarming price variation it might be an idea to analyse why one should pay X rather than Y.

Lets start with the base price of £8 for a Hornby or Bachmann decoder. These presumably are minimum specification so if this could be defined by one of our resident experts then we could build on this and see exactly what we get when we pay more.

What do I get for an extra £4?

What do I get for an extra £8?

What do I get for an extra £20?

Etc, etc.

Lets do a "Which Report" type survey of what is available and what it offers.

If I want a chip that simply enables a loco to be identified and move forward and back do I need to have more than the basics?

Why is one chip aparently offering an identical specification to another considered better?

Happy modelling
Gary

 

[Bilbo]

I thonk if someone was going to do this exercise it would help if they said what loco the decoder fits. My biggest problem is not the number of functions etc but will it fit in the intended loco.

 

[ashleyh]

Gary, I'm up for contributing to this discussion, but not this week as I teach and this week we are being inspected

!!

However, just for openers I've tried all sorts of DCC Decoders from various manufacturers and I can say there is a massive difference between the best and worst.

How does this manifest itself? In how smoothly and quietly a loco can be controlled, and whether or not a constant speed is maintained under varying load and up and down inclines, for example (Back EMF, Load Regulation).

Also a decoder that is effective with one particular type of mechanism/make will not necassarily be effective with a different one. So there is no one answer for all locomotives.

More later once I've been through the grinder

 

[neil_s_wood]

QUOTE A decoder is a decoder - is it? No it's not, there is a significant difference between cheap ones and expensive ones. The more expensive ones will have additional functions are prepared for add ons such as sound. The basic ones such as those provided by Hornby and Bachmann will allow the loco to move and little else. However if thats all you want your loco to do then thats fine, just go with the cheap ones.

A decent decoder such as Lokpilot or Lenz Gold will have functions which allow you to half the locos speed for better slow speed control and have the locos lights flash on and off and thats before you wire up any functions you had in mind like light or smoke generators.

There is a noticeable difference in control quality especially as regards maintaining a constant speed. My Lokpilot decoders will maintain a relatively constant speed regardless of whether they are going up or coming down a gradient, my Bachmann (old Lenz) decoder in my White Knight does nothing off the sort.

This will get replaced with a Lenz Gold when I receive a batch I order from Germany.

I'm sure this has been discussed before under the DCC section so it may be worth your while looking there. There will be many other features and reasons to buy a decent decoder rather than the cheapest available which I'm sure other people can bring to your attention. A mistake I made initially, by buying Bachmann ones, and will not repeat.

 

[mthornton]

The Bachmann decoder I used (aka Lenz 1014) works pretty well in a Bachmann class 24. You miss out on the really super slow motion, but thats about all.

 

[Gary]

QUOTE A decent decoder such as Lokpilot or Lenz Gold will have functions which allow you to half the locos speed for better slow speed control and have the locos lights flash on and off and thats before you wire up any functions you had in mind like light or smoke generators.

That may be so IF you have a control console that permits this.

Think of a Ford and a Rolls Royce. Both have motors that get you from A to B and perform that function. The Rolls Royce offers more functions and the performance to get you there is better.

We can look at performance and function.

The more functions a chip offers the more expensive it normally is.

In terms of performance this is the area that is subjective. Smoothness of performance and how quietly a loco is controlled by a given chip can be factors that affect price.

All most of us want to know is that from a base of £8 for a basic chip that is a Ford, what are the advantages of moving up to a BMW or a Ferrari and what are the cost implications of doing this.

If I have a budget DCC control unit am I wasting money having more than a basic chip?

Happy modelling
Gary

 

[neil_s_wood]

QUOTE If I have a budget DCC control unit am I wasting money having more than a basic chip? To be honest, only you can answer that Gary. I made the mistake of buying cheap crappy decoders once and it was false economy as their preformance is rubbish, but that is entirely my opinion. It is quite apparent that you have very different priorities from me when it comes to DCC. All I would suggest is that you buy one good decoder and try it out and then you can judge for yourself.

 

[mthornton]

There are two aspects to the decoder decision; one is features like RailCom, ABC, Power1, number of auxillary outputs, while the other is the quality of the motor control. For an engine which runs well and has good flywheels you can use a decoder which isn't quite as good on motor control without losing so much.
Under motor control various aspects are:
1. BEMF or load control. Is it present and how good is it.
2. Silent drive. High frequency control results in a near silent motor, otherwise there is a noticeable buzing or growling.
3. How much effort is required to configure. The TCS decoders can produce reasonable running, BUT may take a while to find the best values for various CVs.

RailCOM (or its equivalent from Digitrax): the decoder can send information back to the command station
ABC: Automatic breaking control. Can automatically bring the engine to a stop at a signal.

 

[dwb]

>ABC: Automatic breaking control. Can automatically bring the engine to a stop at a signal.

How much simpler module wiring would be if it was DCC with ABC! You wire a stop section with signal at the start of your modules. The signal aspect is controlled by a switch. You don't want trains? Set the signal to danger. Train arrives, slows down and stops. You clear the signal, the trains starts up again....

but it is unreasonable to expect everyone to be DCC - yet...
and you only features like ABC if you pay top dollar.

If only...

David

 

[mthornton]

QUOTE (dwb @ 13 Nov 2006, 22:21) <{POST_SNAPBACK}>and you only features like ABC if you pay top dollar.
The prices aren't too bad for Silver/gold decoders in $ from places like Tony's trains.

 

[Gary]

We can all accept that more functions means more cost. However....

QUOTE For an engine which runs well and has good flywheels you can use a decoder which isn't quite as good on motor control without losing so much.
Under motor control various aspects are:
1. BEMF or load control. Is it present and how good is it.
2. Silent drive. High frequency control results in a near silent motor, otherwise there is a noticeable buzing or growling.
3. How much effort is required to configure. The TCS decoders can produce reasonable running, BUT may take a while to find the best values for various CVs.

....this is the area when it is not clear what you are paying for.

A basic Hornby or Bachmann decoder at £8 may be a Lada or it may be a Ford or it may be a Rolls Royce in terms of the quote above.

How do we know?

And is there absolutely any link between the control console and the decoder performance as described in the quote?

If I have a Hornby Digital Select Console is is pointless getting a £25 decoder?

Happy modelling
Gary

 

[mthornton]

QUOTE (Gary @ 14 Nov 2006, 15:03) <{POST_SNAPBACK}>And is there absolutely any link between the control console and the decoder performance as described in the quote?

If I have a Hornby Digital Select Console is is pointless getting a £25 decoder?

With a basic command station (e.g. the Hornby Select) there is no value in RailCom or in functions which are out of reach of your console (> F8 for the select, or > F4 for a Compact).
Otherwise the decoder performance is unaffected by how much you spent on the console. The ultra slow motion modes will work just as well.
A Lenz Gold could still be worth getting if you also add the Power1 capacitor so that it will coast over bad points in your track, on the other hand it might be rather cheaper to just clean your track!

 

[neil_s_wood]

QUOTE A basic Hornby or Bachmann decoder at £8 may be a Lada or it may be a Ford or it may be a Rolls Royce in terms of the quote above.

How do we know?
Well I know from direct experience that the Bachmann ones are s

t. I wouldn't buy them again.

QUOTE If I have a Hornby Digital Select Console is is pointless getting a £25 decoder?

Why bother buying good decoders when you have a bottom end system to run them on which cannot even begin to make full use of their potential?

You will get improved running quality but not the full use of the decoder. For this you would need a higher spec system.

 

[Gary]

QUOTE Well I know from direct experience that the Bachmann ones are s t. I wouldn't buy them again.

The ones installed in the locos that come with the Bachmann digital sets seem to work fine. They accept a loco address and you can do everything with them that the Hornby Digital and Bachmann EZ-Command consoles command of them. For the lay person starting off with DCC who simply looks at function its very difficult to accept emotive arguments.

Hence QUOTE A decoder is a decoder - is it?

Those advocating higher priced decoders are more likely to score with a technical argument.

Happy modelling
Gary

 

[neil_s_wood]

QUOTE Those advocating higher priced decoders are more likely to score with a technical argument
You have already been given technical arguements. I notice that you did not respond to any of them.

I was responding to specific questions which you asked. If you only want technical responces maybe you should make that clear. There is sufficient information on this thread already to distinguish the benefits of good decoders from cheap ones.

Maybe those advocating higher priced decoders are specifying their personal preferences rather than "trying to score".

 

[Gary]

We were given a list of technical considerations:-

QUOTE For an engine which runs well and has good flywheels you can use a decoder which isn't quite as good on motor control without losing so much.
Under motor control various aspects are:
1. BEMF or load control. Is it present and how good is it.
2. Silent drive. High frequency control results in a near silent motor, otherwise there is a noticeable buzing or growling.
3. How much effort is required to configure. The TCS decoders can produce reasonable running, BUT may take a while to find the best values for various CVs.

What we want to see is emphiric information for the technical considerations above so that we can understand clearly what we are paying for to enable us to establish value.

We all have our own decoder experiances. I personally would find it very hard to condemn a budget decoder because, put simply, it does its job for me!

Happy modelling
Gary

 

[neil_s_wood]

Heres some information on quality decoders;

ESU Lokpilot

QUOTE The LokPilot decoders are the perfect choice for the advanced model railroader. Versatility and reliability are qualities you would expect from ESU. No matter if you operate it using NMRA/DCC or conventional DC, the decoder will automatically detect the operation mode. In DCC mode the decoder determines the number of speed steps and you may select any of 9999 addresses. The individually programmable speed curve allows precise adjustment to match a particular model. Our truly universal function mapping allows all function outputs to be assigned to any of 12 function buttons in any combination. LokPilot supports lighting effects like Mars Light, Ditch Lights, Gyra Light, Strobe Light and many more. The brightness of lighting is individually adjustable.
Of course, the LokPilot offers the unique Dynamic Drive Control (DDC) feature where the Back EMF is active at low speeds for smooth slow running operation with reduced influence at high speeds.
Fitted with overload protection for the motor output as well as the four function outputs, the decoder is extremely robust. It is suitable for DC, coreless and universal motors converted with Hamo magnets. The 40kHz high frequency motor control assures smooth and silent running.
We put great emphasis on maximum performance of our decoders. The motor output handles a maximum current of 1.1A while the function outputs are designed for 180mA each.

Autodetection of digital or analog operation
Suitable for any Digital Command Control (DCC) system, including: Digitrax®, NCE, MRC® DCC, Atlas® commander®, Bachmann® E-Z command®, Lenz® digital plus®, Zimo®, LGB® MTS®, ROCO®, Fleischmann® Twin-Center®
Suitable for AC-, DC- and coreless motors
Super silent running due to pulse frequency of 40 kHz
Perfect load compensation for optimal running especially on uphill or downhill gradients; exceptional slow running characteristics
Load control can be adapted to any motor by means of 3 CVs
Dynamic Drive Control (DDC) - Back EMF active at low speeds for smooth slow running operation with reduced influence at high speeds
Back EMF also active in conventional AC or DC mode - User has full control of motor and acceleration
Acceleration and deceleration can be switched with function button
Switcher mode (half speed) can be activated with function button
Up to 4 auxiliary function outputs suitable for smoke units, interior lighting, automatic couplers, for raising and lowering pantographs, ditch lights or lighting the fire box
Individually adjustable brightness of lighting
Special lighting effects such as blinking, fire box, Mars light, Gyra light etc. can be set for each function individually
New, revolutionary function mapping. All functions can be allocated to any of 12 function buttons. Multiple allocations are possible allowing for the combination of sound and functions e.g. the sound of shoveling coal and light flickering in the firebox
Short circuit protection for motor and function outputs

The Lenz Gold has these features;

QUOTE The DIGITAL plus GOLD locomotive decoder is suitable for all DC locomotives with continuous
current draw of 1.0 Amp. or less. The characteristics of the decoder are:
∗ Super smooth and silent high frequency back-emf motor control.
∗ Supports the industry proposed enhancements to the NMRA DCC Bidirectional data
communication RPs
∗ USP with optional power module for operation on dirty track
∗ Asymmetrical DCC support including directional stopping
∗ Adjustable precision stopping control
∗ Low speed gear for switching operations
∗ Selectable for operation with 14/27, or 28/128 speed steps.
∗ Operation on conventional DC layouts is possible or can be disabled.
∗ Motor output = 1A continuous, 1.8A max, > 5 A stall.
∗ Motor and function outputs protected
∗ Four function outputs rated at 200mA each with advanced function mapping
∗ Directional or independent lighting with dimming and special effects.
∗ Support for Advanced Consist Control and Extended Addressing
∗ Support for programming on the mainline (operations mode programming)
∗ Support for all form of programming as described in NMRA RP-9.2.3
∗ Supports service mode decoder lock
∗ Size: L 0.91" x W 0.66"x H 0.2" L 23.0 mm x W 16.5 mm x H 6.5 mm

BTW empiric means; One who is guided by practical experience rather than precepts or theory.

What you got was my practical experience. My experience of Bachmann decoders is not good.

Hopefully the above will give you an idea what you get for your money. At the end of the day Gary we all buy what we feel suits our needs best. I'm not trying to change your opinion, I'm just answering your questions. If you are genuinely interested in DCC and better quality decoder etc then I would suggest that you have a look at these websites;

ESU
Lenz
Digitrax

 

[Dennis David]

All good stuff and a good question as well. I think the person who goes into DCC should buy a couple of different decoders and try them out for themselve. Then they can decide how smooth is smooth, how constant is constant. What are their own perceptions of these highly subjective topics. How do THEY wish to run their trains.

 

[Mainthreadmartin]

Just to put a spanner in the works with regard to Bachmann decoders :

I bought some Bachman 1 function decoders for about £10 ea. Whilst they worked Ok it was not until I bought some Bachmann 36-553 3 function decoders, again for about £10 off eBay, that I was aware of the BIG difference.

With 36-553 you get Back_EMF ( silent smooth running), Shunting mode function ( ultra slow running ) function to turn off Inertia plus F0 for directional lights. Wow what a difference. All my Bachmann diesels ( 08, 20, 24, 25, 37, 40, 45 ) plus Heljan 47 and Hornby 31 are now fitted with these and they run really well and can crawl along for shunting moves.

I plan to try out some cheap TCS decoders that have Back EMF too.

So, don't rule out the cheap Bachmann decoders. There is now also a Bachmann 4 function decoder.
Ok the drawback is that you can only use 2 digit addressing. I use a Compact so not an issue for me.

BTW I also have some Lenz MAC decoders which are on a par with the early 1 function Bachmann.
They drive old Hornby Steam locos Ok but a bit sluggishly. I suspect a decoder with back EMF will be much better, plus Shunting mode would be useful so they may get replaced eventually.

I have one loco ( Hornby J94 ) with a Lenz gold mini decoder. This works well enough but still a bit rough - certainly not as smooth as the 36-553! I suspect this is because I bought the loco second hand and it had been programmed on a Lenz 100 system. It may need setting up again to suit my Compact. One plus of the Silver and Gold series is the possibility of USP. This will allow smooth running over complex pointwork that would otherwise produce a jerky motion due to power interruptions. Again I plan to experiment with a USP at some stage.

So you don't necessarily have to spend a fortune to get good running

 

[mthornton]

QUOTE (Mainthreadmartin @ 16 Nov 2006, 16:28) <{POST_SNAPBACK}>I plan to try out some cheap TCS decoders that have Back EMF too.
No they don't. While they have better slow speed operation than the simple Lenz LE1000, it is nowhere near as good as BEMF. Their advantage over the Bachmann 36-553 is that they support 4 digit addresses and more functions (4 or even 6).