38 replies to this topic

[exat808]

Wasnt too sure which heading to post this under (moderators please feel free to move it)

I am wondering if any of the electronics wizards out there could design and build a basic initiator device for starting shock tube. They are available commercially ( Dyno- start, and a plug in for Shrike for example) but at silly prices.

Shock tube initiation has its place in certain pyro applications, especially in SFX. We currently use systems based on percussion primers bit we also have a need for a push button option.

[whoof]

Sound interesting, i am prepared to have a go.
Could do with a bit more information though, od dia , any data on ignition energy required ,
And preferably a close up look at an existing (shrike ?) or similar.

[scjb]

The unit I use is 0.75J with a 2.3kV firing voltage (Scorpion HR1 from EIT Corp).

[whoof]

Thanks, is the STC available at reasonable cost ?
It would make prototyping a lot easter.

[exat808]

Sound interesting, i am prepared to have a go.
Could do with a bit more information though, od dia , any data on ignition energy required ,
And preferably a close up look at an existing (shrike ?) or similar.

If anyone needs some shock tube samples mailing to them please PM me.
The interest in this project has surprised me.

[scjb]

I seem to recall Steve M did a bit of work on homebrew electrical initiation. Might be worth getting in touch with him to see if he would swap notes?

The other alternative is a "NoMatch Shocktube Starter"-style pyrotechnic interface to bump up the output from an electric match to something that reliably initiates nonel?

[whoof]

I now have a working prototype.



Box and board were something i made earlier.
Basicaly a 40 v pyro firing box which i have tweaked up to 300v.

Little black box is the pulse transformer similar to the shrike add on adapter.
In bits at the moment as i am waiting for the potting compound to set in the black box.
All i need now is a shock tube connector which i gather is a consumable part for some units.
Would make things much easier if i could obtain one of those.

Edited by whoof, 25 February 2012 - 08:13 PM.

[exat808]

Have also PM'd you.

This link has photos of STCs but no specs.

http://www.blasterst...connectors.aspx

I may be able to source a redundant item or 2 during the week.

[dave]

whoof,

any chance of posting the circuit diagram / components ?

i know some licensed bird ringers who perform canon netting, and their firing box is not really man enough to give them the distances
they need to be from the birds........they are also a charity so dont have much cash.

any help appreciated

dave

[exat808]

whoof,

any chance of posting the circuit diagram / components ?

i know some licensed bird ringers who perform canon netting, and their firing box is not really man enough to give them the distances
they need to be from the birds........they are also a charity so dont have much cash.

any help appreciated

dave

are they looking for a nonel firing system or a more powerful electrical initiation system?

[Arthur Brown]

They should look on ebay (etc) for the next Shrike, that will fire down 1000+ metres of bell wire -should be enough! And if it isn't then maybe it's not safe to fire beyond an a position of clear view. Alternatively they should buy a Cooperman special high voltage firing circuit -yours ready to use for under a hundred pounds

[dave]

are they looking for a nonel firing system or a more powerful electrical initiation system?

basically a more powerful firing system
i've suggested a capacitor discharge system, and the cheapest i have found which i think
would meet their needs is the one from oda enterprises, 8.7joule blasting box.

arthur,
shrikes would do the job, but tend to be a bit pricey, i've got one myself along with a blaster one cap system, cobra, and kingdom unit
boys have to have their toys

dave

[whoof]

whoof,

any chance of posting the circuit diagram / components ?

i know some licensed bird ringers who perform canon netting, and their firing box is not really man enough to give them the distances
they need to be from the birds........they are also a charity so dont have much cash.

any help appreciated

dave

No problem
Circuit is based on the ZXSC440 from RS about 1.30.
The application notes give the basic circuits.
If you have problems with the transformer PM me i have loads.

I can email the diagram of my gear if needed, it uses design spark software which is a free download.

Chip is a surface mount only package photo of mine is here.



This is the most challenging PCB i have ever made, it took about 8 tries to get a worker.

[whoof]

Dave, During prototyping i made some through hole dil carrier boards to mount that chip.
If one of those is of interest pm me.The rest of the components can be standard wire type.
I have some early prototypes one of which may be useful, it would only give the volts though the rest would be up to you.

If you are in a hurry, as mentioned before Cooperman does cd units, iv'e seen one and they pack a good belt.

[dave]

Dave, During prototyping i made some through hole dil carrier boards to mount that chip.
If one of those is of interest pm me.The rest of the components can be standard wire type.
I have some early prototypes one of which may be useful, it would only give the volts though the rest would be up to you.

If you are in a hurry, as mentioned before Cooperman does cd units, iv'e seen one and they pack a good belt.

thanks for the info whoof,
unfortunately ZXSC440 seems to be a discontinued product with rs and is non stock with digikey.
pm sent

dave