LAST SHIPPING DATE FOR 2019 WILL BE THURSDAY 12TH DECEMBER.
SHIPPING WILL RESUME ON THE 6TH JANUARY 2020.

Muzzel Flash and Machine Gun Firing

Forum for asking questions, offering new ideas or facts or suggesting new topics
Post Reply
Steve Stuart
Posts: 649
Joined: Fri Apr 18, 2008 11:34 pm
Location: Oxford
Has liked: 61 times
Been Liked: 47 times

Muzzel Flash and Machine Gun Firing

Post by Steve Stuart » Wed Mar 16, 2016 8:18 pm

Perhaps this might be too broad a topic, but?
I have been trying to search for relevant items on the forum and coming up with a blank. So what I need to have is, guidance on connecting Muzzel Flash and MG Flash LEDs to Benedinni Sound Cards.
Plus a related topic of how to select and connect LEDs together so as to be compatible with the Power of the Sound Card and the 24v Supply of the Tanks.
I hope that, in fact I am sure that, others will be able to provide the links to the topics on the Forum that I cannot find with ease :lol: I have spent a lot of time on this to no avail :roll:
Many thanks
Steve

mark lawson
Posts: 477
Joined: Tue May 14, 2013 9:14 pm
Location: Solihull
Has liked: 1125 times
Been Liked: 80 times

Re: Muzzel Flash and Machine Gun Firing

Post by mark lawson » Wed Mar 16, 2016 8:34 pm

Steve, there is an option on the TBS5 for both MG fire and Main gun fire using LED if I remember right its universal output 6 the centre pin is 5v+ top and bottom pins are –negative one of the negatives operates the MG the other the main gun you don’t need resistors for the LED’s as they are built into the board, the MG can be split to operate both hull and turret MG both simultaneously.
Werkstatt - 5 Panzer parts. werkstatt.five@gmail.com
RAG Militärmodellbau
IG Militärmodellbau

User avatar
Adrian Harris
Posts: 3720
Joined: Thu Jul 12, 2007 10:46 pm
Location: Berkshire (UK)
Has liked: 149 times
Been Liked: 253 times

Re: Muzzel Flash and Machine Gun Firing

Post by Adrian Harris » Wed Mar 16, 2016 9:57 pm

An LED is a light emitting diode.

A diode is a semiconductor junction which allows the passage of current when its forward voltage is exceeded.

LEDs emit light, of varying frequencies and hence colour, depending on the material used for the diode junction.

The two important values needed when selecting an LED are:

1) the forward voltage Vf. This is the minimum voltage across the LED necessary to make the diode conduct and hence the LED to produce light.

2) the forward current If. This is the current which will pass when the diode is conducting, up to a maximum, at which point the magic smoke escapes and it stops working.

The Benedini TBS5 is run from a 5 volt supply and has a 270 ohm resistor in series with the main gun and MG outputs on connector 6.

Making the assumption that the LED has a fairly standard forward voltage of 2 volts, we can use Ohm's Law to calculate that the forward current will be the supply voltage less the forward voltage and all divided by the resistance. This works out to be:

( 5V - 2V ) / 270R, which equals 0.011A, or 11mA.

This is fine for a standard LED with a maximum forward current of 20mA or so.

However, to use higher powered LEDs, so that the main gun muzzle flash will be visible in daylight, much more current is needed, which is why I designed the original recoil unit around a high powered transistor switching chip, as the Benedini by itself cannot provide the current necessary to illuminate a high powered LED.

It should also be noted that it will only work when connected the right way round. The picture below shows the ways to identify the positive and negative pins on an LED.
LED Lead Identification.jpg
As Mark stated, the centre pin on the TBS5 is the positive supply, so needs to be connected to the Anode on the LED. The top and bottom pins connect to the negative supply when activated by a sound, so need to be connected to the Cathode of the LED.

If you run two LEDs in parallel, the voltage drop will be the same, but each LED will only receive half of the 11mA, so will be dimmer and may not even light. Also, if the voltage drops across the two LEDs are slightly different, one will take a much higher proportion of the available current than the other, so the subordinate one may not light at all.

If you run them in series, the voltage drop across the pair doubles, so the available current becomes:

(5v -2v -2v) / 270R, which equals 0.0037A, or 3.7mA, which may just light the LEDs. But probably not.

Adrian.
R.I.P Margaret I.L.Y

Steve Stuart
Posts: 649
Joined: Fri Apr 18, 2008 11:34 pm
Location: Oxford
Has liked: 61 times
Been Liked: 47 times

Re: Muzzel Flash and Machine Gun Firing

Post by Steve Stuart » Thu Mar 17, 2016 10:41 pm

Thank you Mark and Adrian for your replies, food for thought.
It seems that connecting MGs is relatively easy. I will use an Action Electronics Switch, which I have used on my Tiger and Mark IV for a variety of functions. The question is how to run a more powerful LED set up suitable for Muzzle Flash. Is there, or do you have Adrian, an independent switch/device that will allow say the Tanks 24v supply to run a cluster of LEDs? Or is the electronics simple enough for a safe build?
Steve

Maarten Schutjes
Posts: 197
Joined: Mon Mar 19, 2012 7:01 am
Location: The Netherlands

Re: Muzzel Flash and Machine Gun Firing

Post by Maarten Schutjes » Thu Mar 17, 2016 11:01 pm

It's very easy to build a switch that connects with a battery (2x 1,5 volt in my case) and the benedini sound card.

I use it in my Panther

http://www.armortek.co.uk/Forum3b/viewt ... 875#p33137
____________________________________________________________________________________
Interested in animatronics for your tank? Contact me at westfrontcustoms@gmail.com | See examples at http://westfrontcustoms.nl

Steve Stuart
Posts: 649
Joined: Fri Apr 18, 2008 11:34 pm
Location: Oxford
Has liked: 61 times
Been Liked: 47 times

Re: Muzzel Flash and Machine Gun Firing

Post by Steve Stuart » Fri Mar 18, 2016 1:09 pm

Maarten, your U Tube Video is coming through as not available, so are you able to provide a circuit diagram so I can get the soldering Iron out and reproduce your Switch?
It seems that is the way to go!
Thanks Steve

Maarten Schutjes
Posts: 197
Joined: Mon Mar 19, 2012 7:01 am
Location: The Netherlands

Re: Muzzel Flash and Machine Gun Firing

Post by Maarten Schutjes » Fri Mar 18, 2016 7:09 pm

Hello here is the diagram for the Muzzle flash in 5 volt, 12 volt or 24 volt. You can use it with 2 watt high density leds. One of my electronic wiz brothers designed it for me a year ago.

Image

I've just made an example to give you an impression of the materials used

Image
Image
Image


It works for me and my Benedini, but, as always, Soldering is at your own risk :)
____________________________________________________________________________________
Interested in animatronics for your tank? Contact me at westfrontcustoms@gmail.com | See examples at http://westfrontcustoms.nl

Steve Stuart
Posts: 649
Joined: Fri Apr 18, 2008 11:34 pm
Location: Oxford
Has liked: 61 times
Been Liked: 47 times

Re: Muzzel Flash and Machine Gun Firing

Post by Steve Stuart » Fri Mar 18, 2016 9:12 pm

Hi Maarten
I must confess I do not follow your circuit diagrams. For a beginner such as my self to understand, ought there not be wires returning to the Negative pole of the Battery and to the common pin of the Benedini board? if so they don't appear on the circuit diagram.
Perhaps a photo of the underside of the circuit board might help to augment the diagrams?
Apologies for my confusion, I appreciate your help. Steve

User avatar
Adrian Harris
Posts: 3720
Joined: Thu Jul 12, 2007 10:46 pm
Location: Berkshire (UK)
Has liked: 149 times
Been Liked: 253 times

Re: Muzzel Flash and Machine Gun Firing

Post by Adrian Harris » Fri Mar 18, 2016 9:17 pm

The downward pointing arrows indicate the ground connections for the Benedini and battery, which are common anyway.

Adrian.
R.I.P Margaret I.L.Y

Steve Stuart
Posts: 649
Joined: Fri Apr 18, 2008 11:34 pm
Location: Oxford
Has liked: 61 times
Been Liked: 47 times

Re: Muzzel Flash and Machine Gun Firing

Post by Steve Stuart » Fri Mar 18, 2016 11:24 pm

Thanks Adrian. There does seem some thing intuitively wrong about connecting a 24v and 5v circuit together. Steve

User avatar
Adrian Harris
Posts: 3720
Joined: Thu Jul 12, 2007 10:46 pm
Location: Berkshire (UK)
Has liked: 149 times
Been Liked: 253 times

Re: Muzzel Flash and Machine Gun Firing

Post by Adrian Harris » Fri Mar 18, 2016 11:36 pm

You're just using the 5v circuit to operate a transistor switch on the 24v circuit.

There should be current limiting resistors for the LEDs in those diagrams - you don't want to be putting 24v directly across them :!:

Adrian.
R.I.P Margaret I.L.Y

Maarten Schutjes
Posts: 197
Joined: Mon Mar 19, 2012 7:01 am
Location: The Netherlands

Re: Muzzel Flash and Machine Gun Firing

Post by Maarten Schutjes » Sat Mar 19, 2016 12:05 pm

Adrian Harris wrote:You're just using the 5v circuit to operate a transistor switch on the 24v circuit.

There should be current limiting resistors for the LEDs in those diagrams - you don't want to be putting 24v directly across them :!:

Adrian.
I used LEDs with built in resistors, voltage dependent.
Otherwise, yes, you have to use limiting resistors.
____________________________________________________________________________________
Interested in animatronics for your tank? Contact me at westfrontcustoms@gmail.com | See examples at http://westfrontcustoms.nl

Post Reply