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[SimonCornes]

Can anyone recommend a device that achieves this please? Getting hold of a blue LED should be easy enough but I want something that will make it flash on then off at about a 1 second interval. I have no idea where to find such a thing!!
Thank you.

[Abandon Ship]

Flashing LED's are widely available but I don't know how fast they flash, someone else might be able to help with that.
If you fancy a small challenge you could look up "555 timer" and build your own. You'll need to be handy with a soldering iron and calculator to work out resistor/capacitor values (or cheat and use one of the many published circuits).

[HMS Invisible]

https://www.google.com/search?q=led flasher 1 Hz
www.ebay.co.uk led flasher ic 1hz

[Treble]

Try Leeds Model Shop . They normally stock different flashers , some complete with assorted LED's .Also try Component Shop .

[chas]

Just get one of these simple cheap adjustable units from ebay.
http://https://www.ebay.co.uk/itm/141830849224?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20220405142716%26meid%3Df43d0b243fd740818b5c60c70ae54ded%26pid%3D101506%26rk%3D1%26rkt%3D10%26sd%3D130859902492%26itm%3D141830849224%26pmt%3D0%26noa%3D1%26pg%3D4481478%26algv%3DDefaultOrganicWebWithV11WebTrimmedV3VisualRankerWithKnnV3AndUltBRecallAndCassiniEmbRecall&_trksid=p4481478.c101506.m1851

[chas]

http://https://www.ebay.co.uk/itm/141830849224?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20220405142716%26meid%3Df43d0b243fd740818b5c60c70ae54ded%26pid%3D101506%26rk%3D1%26rkt%3D10%26sd%3D130859902492%26itm%3D141830849224%26pmt%3D0%26noa%3D1%26pg%3D4481478%26algv%3DDefaultOrganicWebWithV11WebTrimmedV3VisualRankerWithKnnV3AndUltBRecallAndCassiniEmbRecall&_trksid=p4481478.c101506.m1851


Oops, sorry about that, this link should work.

[SimonCornes]

No, unfortunately neither work !

[SimonCornes]

Try Leeds Model Shop . They normally stock different flashers , some complete with assorted LED's .Also try Component Shop .

Thank you

[HMS Invisible]

https://www.ebay.co.uk/itm/266368370782

Two for £6.28 with longer delivery time.
https://www.ebay.co.uk/itm/314891459657

[SteamboatPhil]

Component  shop are another good source

[SimonCornes]

https://www.ebay.co.uk/itm/266368370782

Two for £6.28 with longer delivery time.
https://www.ebay.co.uk/itm/314891459657

That’s a very good option but it says it’s designed for 9 - 12v whereas I want to use 6v. I wonder if the electronics would work on 6 with a 3v LED and a resistor?

[HMS Invisible]

The high voltage is almost certainly to do with driving leds in series.
The integrated circuits work down to 3 volts, so you are making the tiniest circuit adaptation.

On weight saving, if you look on ebay you'll also find 1s boost modules that could replace the 1.3Ah Pb battery, taking supply from a 500mAh disposable vape battery. The 1s to 5v boost circuit of £2 poundland phone banks is only good for 0.5 amp.

[Abandon Ship]

One of the ebay links shows a circuit diagram which looks a bit odd. The 4017 chip is used in a very strange way, it's flashing one bank of LED's on and off 3 times then the other bank 3 times. This may be because it's overdriving them at 12v and giving a cooldown period.
Around 40-50 years ago I built a circuit with these 2 chips and LED's as a darkroom timer - the 555 pulsed the 4017 once a second which lit 10 red LED's in sequence then repeated.



At 6v you may find the flash speed is different from the 9-12v rate.


As for LED /resistor values - at 6v you'll lose 0.7v through the transistor leaving 5.3v, so if your LED has a forward voltage of 3v, you'll need a resistor of 110 or 120 ohms for 1 led. If you just use the 555 chip to drive 1 led, the 4017 and transistors are not needed.


I'm not sure this device is ideal for you but if you let us know exactly what you are trying to achieve (flash rate, on/off times, number of led's), we might be able to give better advice between us.

[HMS Invisible]

One of the ebay links shows a circuit diagram which looks a bit odd. The 4017 chip is used in a very strange way, it's flashing one bank of LED's on and off 3 times then the other bank 3 times. This may be because it's overdriving them at 12v and giving a cooldown period.
Around 40-50 years ago I built a circuit with these 2 chips and LED's as a darkroom timer - the 555 pulsed the 4017 once a second which lit 10 red LED's in sequence then repeated.



At 6v you may find the flash speed is different from the 9-12v rate.


As for LED /resistor values - at 6v you'll lose 0.7v through the transistor leaving 5.3v, so if your LED has a forward voltage of 3v, you'll need a resistor of 110 or 120 ohms for 1 led. If you just use the 555 chip to drive 1 led, the 4017 and transistors are not needed.


I'm not sure this device is ideal for you but if you let us know exactly what you are trying to achieve (flash rate, on/off times, number of led's), we might be able to give better advice between us.

I just saw the circuit for the first time a moment ago.
A two second glance confirmed exactly what I thought in my previous post. At six volts it won't drive all three blue and strings of four red in series. It can be changed to parallel.
  There is no voltage dependence on the frequency.
The diagram shows the 4017 outputs use diode logic in wired-or. So all 12 blue alternate with 12 red.
It's ideal with no issues at all. You'll find it better to use the more accurate model for leds is with lower V_on & 20 ohm internal resistance if the external series resistor is only 100 ohm.

You can adapt the led drive to a constant current, Id= 0.6/R, circuit with another resistor & signal transistor. So 4 to 15 volt in supply shows no difference in brightness.
I think using a receiver pack or esc bec for lights is a bad idea.
https://www.onsemi.com/download/data-sheet/pdf/ss8050-d.pdf
If you had electronic scrap components, and thin ply or card, this circuit with constant current led driver does the job without the versatility the kit modules provide. Link

[SimonCornes]

Well I ordered one last night anyway. That’s because I realised that a PP3 is 9v so I’ve got around that problem. I only want one LED of course so I’ll just solder a fly lead to one of the blue LED positions on the circuit board and then see what happens. I’m hoping that it will just work and then i can play with the flash rate using the pot. Or is it not as simple as that? I like ‘simple’ !

[HMS Invisible]

I added a link to a simple astable circuit as you were typing.
The kit has all the components to drive a blue led apart from ~33 ohm that fixes a constant current of (0.6/33) or ~ 20mA.

[SimonCornes]

I added a link to a simple astable circuit as you were typing.
The kit has all the components to drive a blue led apart from ~33 ohm that fixes a constant current of (0.6/33) or ~ 20mA.

Unfortunately I'm not an electronics expert like you! I can quite happily build Maplins and Action electronic kits but after that it all goes over my head !
Hopefully the kit as provided will do what I want? My intention is to not fit any LED's apart from a flylead from one of the blue LED positions which can then go to the single light I need for the boat. Goodness knows where the power supply for this board attaches but I have a PP3 connector on a lead I can use so that shouldn't be a problem

[SimonCornes]

One of the ebay links shows a circuit diagram which looks a bit odd. The 4017 chip is used in a very strange way, it's flashing one bank of LED's on and off 3 times then the other bank 3 times. This may be because it's overdriving them at 12v and giving a cooldown period.
Around 40-50 years ago I built a circuit with these 2 chips and LED's as a darkroom timer - the 555 pulsed the 4017 once a second which lit 10 red LED's in sequence then repeated.



At 6v you may find the flash speed is different from the 9-12v rate.


As for LED /resistor values - at 6v you'll lose 0.7v through the transistor leaving 5.3v, so if your LED has a forward voltage of 3v, you'll need a resistor of 110 or 120 ohms for 1 led. If you just use the 555 chip to drive 1 led, the 4017 and transistors are not needed.


I'm not sure this device is ideal for you but if you let us know exactly what you are trying to achieve (flash rate, on/off times, number of led's), we might be able to give better advice between us.

One LED, flash rate about once a second. Well more like one second 'on' and one second 'off', maybe a bit less but pretty much to match a standard blue light. It seems very simple to me but if its electronics then I expect it isn't, thats why I wondered if I could by a module off the shelf with a light on one end and a power lead on the other!

[Stavros!]

https://www.componentshop.co.uk/voltage-reducer.html


Well if i can use one anyone can solves all the problems.....I use then on my model railway and power up 40 odd leds inc 4x blue flashing leds and they will run all day at a railway show

Stav

[Colin Bishop]

Is this what you meant Simon?

https://www.railwayscenics.com/diffused-blue-flashing-with-integrated-chip-p-3900.html#description

Colin

[HMS Invisible]

One LED, flash rate about once a second. Well more like one second 'on' and one second 'off', maybe a bit less but pretty much to match a standard blue light. It seems very simple to me but if its electronics then I expect it isn't, thats why I wondered if I could by a module off the shelf with a light on one end and a power lead on the other!

The kit modules are for versatility. The Ebay circuit gives you equal on/off and rate adjust.
I only saw timing spec for flashing blue wired leds is at switch electronics.
Switch stock items were wired for 12v in clear epoxy showing blue.
What they say:
3mm diameter LED (also 5 & 10mm)
Flashes approximately 3 times every 2 seconds
Waterclear lens
Input voltage: 12VDC
DC forward current: 20mA (typical)
Excellent weather resistance
UV resistant epoxy lens

[SimonCornes]

Is this what you meant Simon?

https://www.railwayscenics.com/diffused-blue-flashing-with-integrated-chip-p-3900.html#description

Colin

I may well have to buy a few of those plus appropriate resistors - thank you very much for the lead! Who would think everything was built into the LED?? Remarkable and ridiculously cheap although I expect the postage will be out of proportion but no problem ! Don’t know what I’ll do with my eBay gizmo now! Thank you Colin

[Abandon Ship]

Full circle back to the flashing LED's I suggested at the beginning then! Just out of curiosity what sort of model is it for?
And how's the Trent getting on?

[SimonCornes]

You know, even though you said it in your initial reply, I didn't appreciate that you could buy flashing LED's, I thought it was an LED with a separate flasher circuit of some sort!


The light is for the Trent. The motor department is improving. I ran it with a pair of 540/1 motors and a 5000 3S LiPo and the motors behave properly and the top speed isn't bad but if I move the 6v gel cell (used for the boat lighting) further aft to just in front of the motors and LiPo then that might make there bows more likely to come out of the water at full throttle. I'll try that and if it doesn't work I may go for a small capacity LiPo - 2-2300 maybe - and possible 4S instead of 3S but I'll see what the effect of moving the SLA is first. Getting there! The biggest problem now seems to be getting lightweight fabric RNLI flags that fly properly instead of looking like wooden boards! What a great game!

[Treble]

Simon , With reference to the need for a 6 volt supply for your lights , have you considered exchanging the SLA for one of the smaller and lighter voltage regulators from Component Shop to work from your LiPo ?