T&L Publications

I think that might be a passive buck-boost transformer arrangement. Purpose is to keep the the charging voltage constant as the ac input voltage varies within a certain range . The capacitor and inductor form some kind of tank circuit I guess.

Steve G.

OK, circuit modified. Adjust the level of the input sinewave to trigger the 550 at the peak.

Steve G.

A 550 monostable from High Tech Chips will get you a 10us 0 to 5 volt pulse with a 1 volt 50hz sinewave input.

http://www.hightechips.com/Download/htc550.pdf



Steve G.

One possible IC amplifier chip is the LM3886. Assuming the speaker is 8 ohms this will provide 38 watts of power which is probably loud enough. It does require plus and minus 28 volt supplies though. Another possible solution is to use a high power darlington xistor driving the speaker directly sinc...

Here's a simple analog design using a 556. You can vary the resistor values to change the tone and speed as desired.

Steve G.

You can get a discrete bridge rectifier and capacitors from Mouser. The parts are in stock and no minimum order is required.
Steve G.


http://www.mouser.com/Search/ProductDet ... LWlg%3d%3d

http://www.mouser.com/Search/ProductDet ... d6xw%3d%3d

Craig,

I would connect the xformer windings for 12 volt operation. Use a 25 amp bridge rectifier and two 4700uf/25 volt capacitors .This will provide a 16 volt dc output for the controllers

Steve G.

Craig,

The specs on the other two controllers would be a big help. What is the max and min voltage output from the controller when the train is operating?

Steve G.

Here's another timer version that may work. Output is low when first powered up then goes high at the end of the 10 second delay. Output stays low and resets timer when the brake is applied.

Steve G

Don't know for sure would just have to try it. Might just need a few extra turns. The magnet wire is usually better because it allows the windings to be closer together due to the lack of the vinyl insulation.

Steve G

Use figure "a" single ended tuned input. I don't see any problem with this arrangement. However, if you look at the end of the article on page 47 "From Here", you can wind a secondary coil over the primary as the author suggest.

Steve G

Lenp, Unfortunately not. I'm only a beginner at Picaxe myself. I did post a similiar question on the "Picaxe Forum" and most of the responses were over my head. I don't know exactly what you are trying to do with the circuit, but the code works and does save some memory space. http://www.p...

One possible way is to use the command "let pins = b0". This will make the variable b0 equal to the status of the input pins on the port in a binary notation. For instance if all the inputs are normally low then b0 will have a value of 00000000 or zero. Say inputs 1,2 and 4 are high then b...

Easier and less expensive to buy then build in this case.

http://www.nextag.com/7-day-timer/search-html

Steve G

rolerbe,

If your circuit looks like this it should work ok as long as the transformer will handle the current required.


Steve G