Very Low Frquency V to F convertor.

[dr pepper]

Even more than that:

Like all 2 stroke diesels it cannot run without a blower.
Neither me or the mrs likes soaps of any kind.

 

[muso52]

OR MAYBE CORRIES ON RIGHT NOW AND YOUR WIFE LIKE MINE WANTS US OUT OF THE ROOM. OR DO YOU WATCH IT WITH HER!!!!


Willy

only playing.......

The Deltic Rail engine had 2 napiers. 2 X 12cyl?
willy

 

[muso52]

18cyl's per each engine delivering 1650 hp each
Use in quite a few RN craft
willy

 

[dr pepper]

There are a number of deltic variations, not sure what went in trains, though there were at least 2 versions, is it the class 55 that is the baby deltic?
Theres a fire breathing version that makes silly power too, I think it was a proposal to make a diesel powered super quick airoplane.
The deltic by the way was a german idea, junkers, only they couldnt get it to work, napier did.

 

[schmitt trigger]

Muso52,
I'm sorry I cannot provide better solutions to what has already been posted....
But keep the good work! Model trains are fascinating indeed!

 

[Ian Rogers]

I have been studying DCC and the MNRA protocol... I have two bridge drivers here ready to go..

I am going to make a miniDCC booster fit for four trains, and I'm going to make the four decoders for my steam trains..
My only concern is driving a small SD card under these conditions.. I would have to run the decoders at 3v3 instead of 5v to see if I can get several sounds out in harmony.. I have to do the exercise first!! I'll keep you informed..

 

[dr pepper]

Ian what do you think to the speed of Dcc, I'm not so sure it'd be quick enough for scalextric applications, maybe thats why they have their own, or maybe its a copyright thing.

 

[Ian Rogers]

Ian what do you think to the speed of Dcc

seems to be 9600 baud... but if you make the encoder and decoder, you make it any speed you want!

There is a good site with miniDCC schematics... https://www.minidcc.com/

 

[dr pepper]

I must've misunderstood something there then thats around 200 frames a second, plenty quick enough to slam the brakes on.

 

[dr pepper]

Muso, remember the circuit I posted, I got it to do as your spec, it stops completely below 0.6v input, I just added 2 resistors and a transistor, the chip is disabled below 0.6v.
The circuit might need some slight value tweeking, but it works ball park, on 12v from 0.1hz to about 11hz, if your interested let me know.

 

[muso52]

Muso, remember the circuit I posted, I got it to do as your spec, it stops completely below 0.6v input, I just added 2 resistors and a transistor, the chip is disabled below 0.6v.
The circuit might need some slight value tweeking, but it works ball park, on 12v from 0.1hz to about 11hz, if your interested let me know.

dr pepper you are a star!
the chip is disabled below 0.6v.
That would be to my advantage as a dc motor dosn't start to turn untill aboult 1.5v which would have an effect, but as you say it can be tweaked.
Of interest did you try this on a sim packeage?

Thanks an excited willy!
Ps Oh yes very interested!

 

[muso52]

There are a number of deltic variations, not sure what went in trains, though there were at least 2 versions, is it the class 55 that is the baby deltic?
Theres a fire breathing version that makes silly power too, I think it was a proposal to make a diesel powered super quick airoplane.
The deltic by the way was a german idea, junkers, only they couldnt get it to work, napier did.

is it the class 55 that is the baby deltic?

No. The big Deltics on the East coast mainline were the twin engined versions. The baby deltic did not last long enough into the sixties to receive a TOPS code,Class 55 Deltic etc. It was not a success but I do not know if it had a napier engine or got its nick-name because it looked like a smaller version of the Class 55

 

[muso52]

Muso52,
I'm sorry I cannot provide better solutions to what has already been posted....
But keep the good work! Model trains are fascinating indeed!

Thanks for your comments and interest.
Willy

 

[muso52]

I have been studying DCC and the MNRA protocol... I have two bridge drivers here ready to go..

I am going to make a miniDCC booster fit for four trains, and I'm going to make the four decoders for my steam trains..
My only concern is driving a small SD card under these conditions.. I would have to run the decoders at 3v3 instead of 5v to see if I can get several sounds out in harmony.. I have to do the exercise first!! I'll keep you informed..

With the utmost respect Ian are you sure you know what you are letting yourself in for? Without your obvious skills and knowledge I would fear to tread where you are going. It is not the fact that it can not be done as you say but? Where to place the electronics?. Latency of SDD cards?. Memory? Addressing?Audio provision? Speakers? Obtaining and editing suitable sounds?
Retail sound decoders for DCC are available. So why do I not to go down that route? As I believe I said previously, cost and poor quality of sounds. However I wish you success and will watch with interest.
Willy

 

[muso52]

The circuit might need some slight value tweeking, but it works ball park, on 12v from 0.1hz to about 11hz, if your interested let me know.

Is that the V drop over one of the transistors (the .6v)? As I alluded to above one thing not mentioned was that a dc motor will not turn until aprox 1.5 - 2.0 v
Obviously the above will not impact on that but it would seem feasible if it were a 'junction' to sort of calibrate it to the movement aspect with additional diodes.
Also with complete independance of the 2 aspects I can match movement to 'triggers' ie sound. i.e I can raise max voltage out to that what better visually and soundwise matches the 11hz.
Willy

 

[Ian Rogers]

cost and poor quality of sounds

Don't be too alarmed... I can get a decent quality of sound from a pic18f1840.. A min SD will fit under the micro... When I get a bit of time, I'll give it a go..

 

[muso52]

Don't be too alarmed... I can get a decent quality of sound from a pic18f1840.. A min SD will fit under the micro... When I get a bit of time, I'll give it a go..

Its integrating the sound with the movement of a steam engine is the difficult bit. But forgive the pun I am all 'ears'.
Suitable cylinder and clanking sounds are triggered on dcc sound chips by utilising bemf I believe.

Willy

 

[Ian Rogers]

Its integrating the sound with the movement of a steam engine is the difficult bit

sensor on the running gear will do the job..

 

[dr pepper]

Ok the, heres the modded schem, note that the supplies are all now +12v, and there is bottom left a level shifter transistor that gives you a 0-5v Ttl compatible output, or if you want you could make this 3.3V, note the resistor on the collector goes to +5v not +12v.
12v makes the circuit works a lot better, the 4046 is a cmos cd4046, a 74hc4046 would not work here, but the cmos version 4046 is still common.
Instead of a 2n2222 you could use Bc547, 2n3904, Bc107, Ztx457 etc.

 

[muso52]

Hi drpepper,
many many thanks for the circuit. Would this be ok?
**broken link removed**
**broken link removed**
Also, have 15v circuit to hand from previous project. Can it be used? Do not see any probs.
Finally for the moment, I am assuming the 47k pot adjusts output frequency? And just one more thing (for the moment) What is the 1K pot on pin 9 doing? Is it a trimmer?

the chip is disabled below 0.6v.

Is this still relevent?

Am aiming to source all components from CPC draw circuit up for vereboard and get back to you soonest.

Thanks again,
Willy