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Tricky Dicky

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Everything posted by Tricky Dicky

  1. Someone who is familiar with this decoder might be able to confirm or deny this but that looks like a customized integrated circuit not a blister. Components like this are often seen in space critical situations such as circuits in musical greeting cards. Richard
  2. Try using the bezels in the following link, you push the LED in first then push the bezel into the mounting hole it has a good interference fit and at the same time locks the LED in, further down are some solderless LED holders these a tight push fit on the LED legs which do have to shortened but you can still identify the cathode of the LED by using the small flat on the bottom rim of the LED. The solderless holder fits inside the bezel. This should solve your movement problem as well as saving a little soldering. http://m.rapidonline.com/Mounts-Holders Richard
  3. The M1 transformer is the cased version, the above applies to the T1 type which is an uncased transformer. Richard
  4. Kytes Lights have a fairly close replacement which could be fettled to look like the original. http://www.kyteslights.com/product_info.php?cPath=24&products_id=332 Richard
  5. I refrained from mentioning SMD LEDs which are hard enough to solder onto a PCB let alone attach flying leads to. Even Richard Johnson mentions the high loss rate in production, hence the premium price. These are probably your answer Julia. Richard
  6. You can get through hole LEDs as small as 1.8mm http://www.rapidonline.com/Electronic-Components/Miniature-1-8mm-High-Power-LEDs-73568 The problem is that it is only the domed part that is that diam. the other part of the body is about 3mm wide to accommodate the standard leg spacing of 2.5mm. Wether you could fit that into the shade is doubtful. You might be better mounting the LED within the structure and using a light pipe or a length of fibre optic cable to take the light out though the shade. Even there you may have issues as there are usually minimum bends to consider. Richard
  7. Metrocab and Chimer you do yourselves an injustice by claiming to to be rubbish solderers. There is usually a good reason why it does not work for you and it is a process of elimination to discover the problem. A clue to your problem Metrocab is your complaint you cannot hold your iron in place long enough to complete soldering. This suggests to me that you may have either an underpowered iron or yours has a badly oxidised tip, small soldered connections should take about 3secs. to complete. Dealing with the latter problem first if your tip is blackened, solder takes a long time to melt and then tends to run off the tip in blobs when it does, this is a badly oxidised tip. The tip should have a thin coating of solder known as tinning and when wiped on your damp sponge should appear silvery, if it does not look like this then you you have not a hope in hell of successful soldering. If this is the problem then the tip needs to be cleaned and re-tinned, care needs to be taken not to remove any coatings on the tip in the process. Cleaning a tip has been covered here before. If you have a correctly tinned tip and still find soldering takes a long time then it is probably underpowered and you need to invest in an iron that is man enough for the job. A good maxim is that you can too little power but not too much. Richard
  8. Rather than simply retiring older locos, why not sell them to fund the conversions. Richard
  9. I agree with you Andrew, I have used Antex irons and treated carefully tips will last almost indefinetly, but keeping the coating intact is essential. I have seen many an Antex tip destroyed mainly by the inexperienced abusing the tip and abrading the coating off. As a teenager I had an iron manufacturer unknown which which had an unplated copper tip which lasted me well into adulthood and the tip never needed replacing, unfortunetly some scroat relieved me of it. Richard
  10. Most modern soldering iron tips are made of low quality copper coated in iron carbide. Once you wear through the coating you will find for a while the iron will solder well but over time a cavity will appear and the tip will need replacing. To clean a badly oxidised tip you need to abrade it but you need to be careful not to scratch through the coating, so files, emery cloth and wet n dry are out. A brass brush is the answer, I had a technician who managed to revive some really badly oxidised tips using a small brass wire brush in a Dremel type tool. Once clean the tip needs to tinned as you have been advised already. Not getting to the point where your tip becomes covered in crud is the answer to getting a long serviceable life out of your tip. The crud that develops on the tip is mainly oxides of lead and tin, the tin being the harder oxide. If your iron spends long times sitting hot in the soldering stand the flux burns off and the constituents of the solder vapourise as well leaving the oxide crud. This is one of the reasons why lead free solders are used these days. Keeping the tinning refreshed is way to do it, if you are doing a lot of soldering then this will happen as a result of the process. If as mentioned already your iron is spending a lot of time in the stand then you periodically need to add solder. Your sponge is your friend in keeping the iron clean, I always give it a wipe before soldering and after each bit of soldering. Why? Oxides are suspended in the flux once it burns off they settle on your tip, wiping the tip regularly removes these suspended oxides. It will not stop the tinning from further oxidation that is something that will happen where heat is involved but the less you have to deal with the easier it is to keep the tip clean. Finally when you have completed soldering always wipe the tip so you can see a silvered tip before switching off the iron. You mentioned that the sponge was cooling your iron down. That may be because you are holding it in the sponge too long, a quick wipe is all that is needed. Holding it in the sponge too long could be where you are picking up detritus that is contaminating the tip. Richard
  11. They are called Scotchlok connectors being an IDC (Insulation Displacement Connector). Therein lies the problem with them, they are really only designed to link two wires of similar diam. With a little leeway on the actual diameters. If you have widely different diameters in the two wires being linked then the following problems can occur. Get one to suit the thickest wire and the blade that makes the connection inside may not adequately displace the insulation on the thinner wire, whereas get one to suit the thin wire and you may find the blade almost severs the thicker wire. You will get get a lot of varying opinion on them but on a personal level as someone who has worked in electronics for much of my professional life, I would not touch them! Soldering is your most reliable method. Look at the DCC Concepts site, Richard Johnson has an interesting method of soldering droppers based on using automatic wire strippers to displace a section of insulation and three terminal tag strips. The finished result not only holds your bus wire securely below the baseboard but also whilst soldering you do not have wires flopping about. Richard
  12. It cannot be done with a standard bi-colour LED as the two colours are connected in reverse to each other and therefore the current has to be reversed to display the other colour. To do what you want you need a tri-colour LED which either has a common anode or cathode. Richard
  13. Probably not is the answer. You can get flashing LEDs which are usually 12v. The only other way I can see you achieving it with a single LED is use the three pin types which have a common anode and use an astable circuit such as one based on a 555 timer. You would only need one astable to flash all your red LEDS. The two pin bi-colour LEDs are actually two LEDs wired in reverse to one another and the colour lit dends on the direction of the current. Richard
  14. I do not know where you get the 4V? White LEDs usually require a higher voltage compared to standard LEDs about 3V. Three in series require 9V then there is the current limiting resister wired in series which accounts for the remaining 3V (Ohm's Law). With regards reverse voltage it is commonly higher than forward voltage, therefore if the appropriate current limiting resistor is used your LEDs should not break down if polarity is reversed. I still think your main problem is your PSU is not supplying enough current. Having read the specs. 36W per 5m will require a 3A supply as Crosland said. Even the seller advises a buyer who submitted a question to buy a 6A supply. Richard
  15. If you are trying to light all 300 then your power supply may not be delivering enough current. A white LED typically needs 30mA+ at its brightest. Depending on how the LEDs are wired that that could be as much as 30mA x 300 but it is my experience with these strings of LEDs they are usually wired in groups of three in series with a single resistor for each group of three but that is still 30mA x 100. Richard
  16. I have replied to the other post but just to add to it regards wiring. Terminals D & E should be connected to either your DCC bus or the rails and F to the frog. If you experience a short then swap over terminals D & E. Richard
  17. According to the specs. It should change the polarity. I would check your wiring, having said that they do have a reputation for problems with the switch which can be induced by poor installation. If that is the case you will not get it to power your latching relay either. So check wiring, check the installation particularly that the PCB is not flexed. If everything is OK then send back to your supplier for an exchange. Richard
  18. My only concern is the on board polarity switching and LED switching as the only sure fire way of knowing a point has moved is by linking a switch to the tie bar. If all the on board LED switching tells you that you have activated a switch to move the point then there could be problems. I may be wrong and admit I have not read the installation instructions but I cannot see how it detects actual movement of the point. Richard
  19. Hi Worzel I have not used a RLM but as far as I know they do not respond to command station commands rather they simply detect the change of polarity and switch accordingly. The only one I am vaguely familiar with is the Lenz LK200 which connects to the track before the loop for power take off and detection which rail is which and connects to the rails within the loop which need to be isolated at both exits of the turnout on both rails. The RLM detects any conflict of polarity and using rapid electronic switching changes the loop polarity before the command station cutout can trip. Richard
  20. With all due respect if you are asking how to wire an open frame transformer here then for safety's sake I suggest you opt for the cased version. Dealing with mains voltage is not for the inexperienced and if anything is done wrong then the consequences could be fatal. Richard
  21. Brilliant layout Jim, but can I suggest you desist from using Laco flux for electrical soldering. It is an acid based flux mainly used by plumbers because it has a cleaning effect it means they do not have to hand clean copper pipe joints. It may be doing a grand job with your soldering but long term you could find problems from residual acid. Any residual flux needs to be flushed away with water, easy to do in a pipe but not recommended for a PCB. Richard
  22. Probably the best book is Brian Lambert's Newcomers Guide to Model Railways or you can go to his website which has got all the information that is in the book. http://www.brian-lambert.co.uk Brian posts on this site and usually responds to queries like yours. Personally, I consider going back to DC as a retrograde step as it does not offer anything near the flexibility of DCC and as you already allude involves a lot of switching sections off and on hence the more complex wiring. As I duck below the parapet! Richard
  23. Should be OK according to the specs the LEDs will have a current draw of 2A and the PSU can provide up to 4A. The only additional item might be the LED strip to power supply adaptor mentioned in the "other items bought with this product", otherwise you will have to remove the plug on the output side of the PSU and make your own connection which probably void the warranty. Richard
  24. Ian You are correct about what a power bus is and that the droppers are the connections between the bus and the rail. Be aware the power bus needs to quite hefty wire as it carries the total current consumed by your layout but more importantly does not cause a voltage drop at the extremes. The droppers can be thinner wire as long as they are not long. Brian Lambert's site has a good graphical explanation of a typical power bus in the DCC section. http://www.brian-lambert.co.uk/DCC.html#Comparison Richard
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