Starship Modeler Discussion Forums

Or you could use something like this, then you wouldn't have to cut the connectors in half and you could make the connections polarised (ie one conection male to female and the other female to male).

https://www.amazon.com/dp/B01M133X6U?psc=1

If you're prepared to do a little soldering, or know someone that can, your most basic option would be to have a go at making one yourself using the ubiquitous 555 or 556 (dual 555) timer chip. Google "Star Trek Nav Lights ne555" or simply go to http://virtualight.com/?p=1199 , there's a g...

Unless it states that it is conductive on the packaging, I'd say no, it doesn't conduct. A lot of RC modellers encase their ESCs in epoxy so it should be safe.
You could make a blob of it then just test it for conductivity with a battery, some wires and a resistored LED to make doubly sure.

You've already seen the circuit :) Its this one: http://www.circuitstoday.com/wp-content/uploads/2009/09/555-astable-multivibrator.jpg Note the addition of the diode across Rb (shown with a dashed line in that diagram) There's some useful info here on how to calculate the values you want more accura...

What strobe pattern is it you want to reproduce MF - single flash?? So if its just a single flash strobe you want to produce, then a single 555 could do the job. R1 = 15k, R2 = 220k, C1 = 10uF and a signal diode (say a 1N4001) across R2 would give you 0.1 sec high (on), 1.5 sec low (off) cycle As a ...

Can you describe how you've got the pins wired?

In theory, those values should give you a single shot of 0.29 seconds, so I can only guess at a wiring issue? Have you wired reset to Vcc to hold it high until triggered?

Here's a very useful online calculator for astable 555 circuits, including one for duty cycles <50%.

http://www.horrorseek.com/home/hallowee ... rCalc.html

I use microprocessors now, but when I used to use 555s or 556s this was always my goto calculator.

If anyone else needs to calculate resistor values for leds, you could do worse than try this site: http://led.linear1.org/led.wiz Generally red or green leds will have forward voltages around 2 - 2.2v and white or blue will be around 3.2 - 3.4v Use a forward current of around 20mA as a maximum. All ...

That should work out to be 130 ohms.

This is a good site for working out SMD codes:
http://www.hobby-hour.com/electronics/smdcalc.php

HTH
Bernie

The only main difference to bear in mind here, except for the actual plug format, is the supply voltage. In the US I believe its 110V ac whereas here in the UK its 240V ac. The PSU highlighted by Madman would do fine as its input voltage range covers both. Just make sure whatever wall wart you choos...

what Mr Engineer said

Bernie

The only downside of that one seems to be the fact that its smd. If you're happy soldering smd components then it shouldn't be a problem. I would think that from the graph on the LM2575 data sheet that at 1A, an inductor of 120uH would do the job. The reason I mention that value is that I can get it...

Bernie - this is a full list of 330uH inductors (axial lead) at DigiKey. There aren't that many, but with many different specs. Do any of them look like they'd match the ones you get from the UK? Don't see any list RossW :? :) Actually, going from your original 58mA @ 5v output requirement, you don...

Those are the ones

Just choose the 1mH choice from the dropdown.
Are you UK based?

Bernie

I bought my inductors from Ebay ( http://stores.ebay.co.uk/sunsphere-components?_trksid=p2047675.l2563 (I'm in the UK)). I'd calculate for your application you'd need a 1H (1 Henry, or 1000uH) inductor part# FALGA0307-102K or check page 17 of the LM2575 data sheet, its got several manufacturers part...

This is the configuration and component values I use with an input voltage of 12v

http://www.flickr.com/photos/38926882@N ... hotostream

Bernie

PS Oooops C4 got truncated - its 100uF

Do you know what sort of current you'll need for the 4.5v supply? I can see two choices - if the current is less than 100mA you could use a L78L05 regulator, but if you need more current, I'd use a step down (Buck) converter such as the LM2575 which is good for up to 1A. Checkout their respective da...

So sad to hear of the passing of this very knowledgeable and helpful man. Condolences to his family.

Chiver,

try this:

http://www.flickr.com/photos/38926882@N ... hotostream

Sloucher

BTW, so as not to hog the board, might be best to continue this thread by PM, unless the mods et al have no objections to carrying it on here if its of help to others as well?

Sloucher

Hi Chiver OK, lets deal with the capacitors first: The larger blue capacitor is what is called an electrolytic, or polarised capacitor. It can only be charged in one direction. In other words, for our purposes, it works one way round but not the other. In the case of the 4.7uF capactor you have, the...

Hi Chiver Nice video - and yes the name's ok!! Two things to mention - first don't connect pin 5 to ground directly. That'll just set the control voltage to 0v and so the circuit won't flash at all. Secondly, can you check your resistor values and double check its all wired as per the 555 astable wi...

OK Chiver - just breadboarded this: http://www.flickr.com/photos/38926882@N03/8170162366/in/photostream Its not quite the speed of flash you want (and I know the led is blue - it was just lying around!), but its just to prove the circuit to you. Cap is 100uF R1 is 2K R2 is 20K If you only have a 4.7...

Sorry for the delay, travelling home!

Let me throw a breadboard circuit together and see if I get any problems. Be back in a coupla hours (gotta go and fetch the wife from work now!!)

Its 2.7 and 27 Kilohms Chiver - thats a factor of 1000
and don't forget that diode

I'll try a few bits and pieces as well l8r

Slouch

For that sort of flash rate you'll need: C1 elect cap = 100uF, R1 (the resistor from +v to pin7) = 2.7 Kohms, R2 (the resistor from pin 6 to pin 7) = 27 Kohms and you will also need a diode (1N4008 should do it) in parallel with R2 with the band on the diode nearest to pin 6. The diode is needed bec...

Pin 5 should really be tied to ground when using the 555 as a timer as pin 5 is the reference voltage input. If its left floating it can cause the timing to drift all over the place. Seems odd it worked before and not now though :? . What fllashing rate are you aiming for Chiver? Let me know what ti...

The only thing I see that I'd change is to fit a small, 0.01uF (10nF), capacitor between pin 5 and ground. Pin 1 must be grounded or the internal comparators can't do their thing. Does the led flash or is it on continuously when it lights? Is the electrolytic cap attached to pin 2 the right way roun...

Your best bet is probably to put your own reference material together from info on this site or via your friend Mr Google, to be honest. Sorry I can't suggest an all in one book.

Hi Rogerp Space is at a premium in this scale of model, so my suggestion would be to use one or two white leds in the saucer section and again one or two in the engineering section for interior lighting. Of course, this does mean making holes to let the light out as required! You could use the self ...

Hi nickymaude I can do a navigation flasher circuit which will flash the red and green leds at any rate you choose and also flash white leds (which I assume you want to represent the strobe marker lights?). The white leds can flash at a different rate to the red/green leds if required. Its the lower...