pillboy Posted April 16, 2006 Share Posted April 16, 2006 Scott- Great job! I am tempted to try this as it looks both fun and useful, but I think I need a little more detail. I am comfortable with basic electrics, but am by no means as knowledgeable as yourself. Mark It is still ugly. Link to comment Share on other sites More sharing options...
scottmcphee Posted April 17, 2006 Author Share Posted April 17, 2006 Scott- Great job! I am tempted to try this as it looks both fun and useful, but I think I need a little more detail. I am comfortable with basic electrics, but am by no means as knowledgeable as yourself. Mark CD4538 is a 16 pin package.. the dot marks pin 1, get the PDF from google.. the 0.1 capacitors are monolythic type, % not critical resistors are 1/4 watt, % not critical diodes are 1n4048, or 1n4002, or .. just about any C is the timing capacitor, electrolytic type at least 25v, + side toward R R is the timing resistor. You can pick the "on" time using different values for R and C, as per http://www.cvs1.uklinux.net/cgi-bin/calculators/time_const.cgi Regards Scott Link to comment Share on other sites More sharing options...
BDII Posted April 17, 2006 Share Posted April 17, 2006 only 3 blinks? I'd write you a BIG FAT TICKET! Need forum help? Private Message legGTLT Link to comment Share on other sites More sharing options...
pillboy Posted April 17, 2006 Share Posted April 17, 2006 I picked R=42K and C=47uF as the timing constant which is about 5 blinks. only 3 blinks? At least I read REV 2. It is still ugly. Link to comment Share on other sites More sharing options...
scottmcphee Posted April 19, 2006 Author Share Posted April 19, 2006 only 3 blinks? I'd write you a BIG FAT TICKET! Even set to 3 blinks, I'd fight your ticket in court, and win. So eat your fat ticket! 11-604.Turning movements and required signals (a) No person shall turn a vehicle or move right or left upon a roadway unless and until such movement can be made with reasonable safety nor without giving an appropriate signal in the manner hereinafter provided. (b) For vehicles equipped with mechanical or electrical turn signals, a signal of intention to turn or move right or left when required shall be given continuously during not less than the last 100 feet traveled by the vehicle before turning. The law also says that signals must blink between 60 and 120 regular pulses per minute. Good news! The Subaru pulse rate is 85 cycles per minute, says right on the module have a look yourself, or measure it if in doubt. Suppose I was traveling in a 50 mph zone, and I was doing 50 mph.. (I didn't get a ticket for speeding, right? It was lane change infraction..) Anyway, going faster than 50 improves the case even more... 50 mph means I'd be doing 73.3 feet per second. The mod sends out 3 pulses. You can show this over and over again in court - that you simply can't get less than 3 pulses out of the car in a given direction. If you leave your lane exactly on the beginning of the 3rd blink then you have traveled for at least 2 complete cycles, which takes more than 1.4 seconds to do, which means you've traveled at least 102.6 feet. Look at that! Within the law. And going faster increases the distance. Considering the mod is really meant for highway use where you don't want to click or hold the stalk to make a lane change, it can really be to your advantage. Maybe it's just nice to know that it's impossible to signal short of the law so long as you use the third blink as your marker for leaving your lane, you're in good shape. Cheers Scott Link to comment Share on other sites More sharing options...
scottmcphee Posted April 19, 2006 Author Share Posted April 19, 2006 By the way, I changed some component values for better performance. R = 36K, C=47uF.. so this is a crisp 3 blinks. And I increased the 10K resistors to 500K ... because when the wheel cancels a signal, there is enough interia in the stalk that sometimes it swings far enough to make contact for signaling the other direction! 500K value snubs this brief contact. Bottom line: now you've got to tap for at least 50 milliseconds to trigger it.. but no big deal.. it's almost humanly impossible to tap the stalk for less than this.. so you can get it every time. We're done! Regards Scott Link to comment Share on other sites More sharing options...
TSiWRX Posted April 20, 2006 Share Posted April 20, 2006 This mod is *sooooo* tempting for my "gadget-must-have" nature. Thanks, Scott, for putting this up and working things out! Now, if baby Anna would just give me enough time alone with the car, I'd have this done! <-- I love Winky, my "periwinkle" (ABP) LGT! - Allen / Usual Suspect "DumboRAT" / One of the Three Stooges '16 Outback, '16 WRX, 7th Subaru Family Link to comment Share on other sites More sharing options...
scottmcphee Posted April 28, 2006 Author Share Posted April 28, 2006 Well, not quite done. With the 500K resistors, the snubber circuit slow rising characteristic can cause a retrigger - you get 3 more blinks.. and it can retrigger again - 3 more blinks... This is not good. It only happens sometimes. However, this is enough to need a fix. So I added a diode across the 500K resistors (left and right halves of the circuit). Connect the diode in parallel with the 500K resistor - cathode to the chip pin. There you go. Times two. Now, as soon as the signal stalk breaks its contact the snubber circuit recovery is immediate.. no longer a slow rising slope in that direction. It does remain slow on its make-contact side, so it still snubs a "wobbly stalk" as it settles into neutral position after the wheel cancels it. So if you're building the circuit.. add the diodes. And life goes on. Scott Link to comment Share on other sites More sharing options...
sgt Posted April 28, 2006 Share Posted April 28, 2006 Would you mind adding that to the diagram you posted? Link to comment Share on other sites More sharing options...
scottmcphee Posted April 29, 2006 Author Share Posted April 29, 2006 Would you mind adding that to the diagram you posted? Sure, I updated the circuit where it appears first, and here too. So it now reflects R=36K the snubber resistor, now 500K and the new diode (in red). Remember the diagram shows only 1/2 of the circuit, which is fine if you only want to have tap turn in one direction ;-) The other half is mirror copy. The new circuit is working solid. Haven't seen a false since. Cheers Scott Link to comment Share on other sites More sharing options...
sgt Posted May 10, 2006 Share Posted May 10, 2006 w00t! I finished it. And it WORKS! Not as small as Scott's, probably not as pretty either lol Link to comment Share on other sites More sharing options...
scottmcphee Posted May 11, 2006 Author Share Posted May 11, 2006 w00t! I finished it. And it WORKS! Not as small as Scott's, probably not as pretty either lol Congrats! Glad it worked for you. Scott Link to comment Share on other sites More sharing options...
Spec-B GT Posted May 11, 2006 Share Posted May 11, 2006 I think you should sell me one to save me all the hassel. Link to comment Share on other sites More sharing options...
sgt Posted May 11, 2006 Share Posted May 11, 2006 Congrats! Glad it worked for you. Scott Couldnt have done it without your help Scott. Thanks so much! Link to comment Share on other sites More sharing options...
mwiener2 Posted May 13, 2006 Share Posted May 13, 2006 where is everyone sourceing parts for this.....radio shack doesn't carry much anymore My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
mwiener2 Posted May 21, 2006 Share Posted May 21, 2006 anybody? parts? My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
scottmcphee Posted May 21, 2006 Author Share Posted May 21, 2006 anybody? parts? parts mostly from local electronics supply stores.. You can get all these pieces in any reasonably large center. If you need a hand, or live in some remote area and need to order over the web anyway.. we'll I've built these for others.. Scott Link to comment Share on other sites More sharing options...
sgt Posted May 21, 2006 Share Posted May 21, 2006 I got what I needed between radio shack and www.futurlec.com I ended up using 36k + 100k pots to get an adjustable count. (I really just wanted an excuse to build another =)) Link to comment Share on other sites More sharing options...
jsalicru Posted May 21, 2006 Share Posted May 21, 2006 For those still curious... 3 flashes is enough. BMW 7 Series has this feature. it blinks 3 times. "some say, his arms are made of coiled adamantium fibers. And that he tops his cereal with nuts and bolts. All we know is, he's called the Jose." Link to comment Share on other sites More sharing options...
scottmcphee Posted May 24, 2006 Author Share Posted May 24, 2006 For those still curious... 3 flashes is enough. BMW 7 Series has this feature. it blinks 3 times. I think 3 is the right number too... it's way better than one, or zero. You realize this mod is just my evil plot to get more people signaling a little more often because now it's got a fun factor to it. With one resistor value change on the circuit, you can change the number of blinks.. if you want 4 or 2 or whatever. Regards Scott Link to comment Share on other sites More sharing options...
JK_Asian Posted May 29, 2006 Share Posted May 29, 2006 I don't get it, so when you mirror the circuit, do you mean you need another chip? Link to comment Share on other sites More sharing options...
scottmcphee Posted May 30, 2006 Author Share Posted May 30, 2006 I don't get it, so when you mirror the circuit, do you mean you need another chip? Nope. The CD4538 chip has two complete timer units on it. One arranged on the pins down the left side, and the other down the right side. Link to comment Share on other sites More sharing options...
JK_Asian Posted May 30, 2006 Share Posted May 30, 2006 Nope. The CD4538 chip has two complete timer units on it. One arranged on the pins down the left side, and the other down the right side.NICE. Thank you so much.. Link to comment Share on other sites More sharing options...
scottmcphee Posted June 9, 2006 Author Share Posted June 9, 2006 Here's the finished kit... and the connectors needed to install it. It's a four wire job.. and two of them are the same color because it doesn't matter which is which for the left or right signal hookup. To put this picture in perspective, the white box is less than 2" square. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 19, 2006 Share Posted June 19, 2006 My buddy and I tried to make one today....i don't think it works I gave it 12v at the ign. Ground at the ground. Hooked up my meter to Ground and left. Touched 12v to Left...got 12v on the meter while i was touching left and then nothing. Hooked up meter to right and ground. Touched 12v to right and got sparks anyone wanna sell me one of these or make a better wiring diagram....perferably a ladder diagram? My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
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