DLM Warp Waddell system

NathanJ · Post by **NathanJ** » Wed Jun 10, 2009 5:32 am

First of all I have to say this is a great kit and reasonably priced if you buy the upgrade parts. My problem is I can't get the ion pods to strobe. The nav lights are working fine, but I can not get those lights to blink at all! Thanks in advance.

RossW · Post by **RossW** » Thu Jun 11, 2009 10:36 am

Not to be picky, but that's "Waddell"

Only mention it as Don named it after me as we worked on it together.

Do you have a voltmeter? Can you see if any current is on the output of the 3909 strobe pin?

NathanJ · Post by **NathanJ** » Thu Jun 11, 2009 4:37 pm

Oh, my apologies sir! I was an AC troubleshooting guy, I have a fluke 322. Hanging head in shame which one is pin 3909? I am assuming it is off the chip. Will check the base solder joints again.

RossW · Post by **RossW** » Thu Jun 18, 2009 10:27 am

3909 is the strobe chip; I think it's an 8-pin IC but I can't remember which ones are the + and - outputs. From the web, I see:

Fit the LED to pins 6 and 8. The short LED leg (cathode) goes to pin 8. The long LED leg (anode) goes to pin 6.

Make sure you are getting around 1.5 VDC between those two pins (on/off of course; it is a strobe

.

Madman Lighting · Post by **Madman Lighting** » Thu Jun 18, 2009 8:24 pm

LM3909? THAT chip? Wow.

I used that chip years ago for a blinky project. Neat little part, easy to use too. Where do you get them? I thought they didnt make them anymore.

USS Atlantis · Post by **USS Atlantis** » Thu Jun 18, 2009 8:43 pm

Madman Lighting wrote:LM3909? THAT chip? Wow.

I used that chip years ago for a blinky project. Neat little part, easy to use too. Where do you get them? I thought they didnt make them anymore.

I think Don said that he laid in a collection of them just before you couldn't get them anymore

That's why none of us can get them anymore - he hoarded the entire remaining quantity

That's ok, I still like the 555 - gives me more control

NathanJ · Post by **NathanJ** » Thu Jun 18, 2009 9:52 pm

I just hope I can get it to work! LOL

RossW · Post by **RossW** » Fri Jun 19, 2009 2:56 pm

Indeed, I'm the one responsible for the worldwide LM3909 shortage. When I was working on the board with Don many eons ago, I mentioned that a local surplus store (Active Surplus on Queen W in downtown Toronto) had a bunch of 'em; I scooped them up and sent them to Don.

What I loved about this chip was how easy it was to get a great looking strobe effect (triangular sine wave). With a 555, I've only ever been able to get a square wave, i.e. 'blinky'. Nowadays, I just use a programmable PIC to do a strobe ...

Mr. Engineer · Post by **Mr. Engineer** » Sun Jun 21, 2009 12:49 am

Ah, the LM3909. It was a fun chip to play because all you ever needed was a capacitor and a resistor to run an LED (it had a voltage booster, I think). Just plug an AA battery in there and it will blink the LED for a few weeks.

The chip went obsolete last millenium and against the still going strong 555, the only application I ever saw was those "torch finders". Perhaps its due to the "limited" market.

But it was also the best quick solution circuit when I wanted a blinkie in a tight space (before SMD technology was available to the masses)