Airstart Relays?

[MaxQ]

Any of you electronic wizards have a good relay design that would light multiple motors from a GWiz or other similar device?

I don't think a GWiz can light four ematches...I have gotten three to light, but four won't.

 

[blackjack2564]

Any of you electronic wizards have a good relay design that would light multiple motors from a GWiz or other similar device?

I don't think a GWiz can light four ematches...I have gotten three to light, but four won't.

Instead of building a relay, buy a Prefect Flite Timer only 35.00 , it will light up to 10 e-matches as is. Tiny, uses a 9v. Simple solution.


https://www.perfectflite.com/cgi/PF...=enter&thispage=miniT3.html&ORDER_ID=!ORDERID!

 

[JDcluster]

What type of batteries are you using?
I've been using the 9.6 volt rated.
It doesn't look like they have the 9.6 volt ones but these are close to it with 300 mAh VS 230.

https://www.thomasdistributing.com/-MAHA-9V-300-mAh-NiMH-Rechargeable-Battery_p_230.html


JD

Any of you electronic wizards have a good relay design that would light multiple motors from a GWiz or other similar device?

I don't think a GWiz can light four ematches...I have gotten three to light, but four won't.

 

[cbrarick]

Go for 325 mAh!
https://www.onlybatteries.com/showitem.asp?ItemID=14718.64&cat1=14&uid=1427

 

[FredA]

IMHO -- using relays is asking for problems....
They can close unexpectatly under shake and shock....NO THANKS!

Use a solid state solution.
I found these Igniter Power Boosters from Dave Flynn.
They work GREAT!

See: https://www.dmf-rockets.com/products/index.html
See the third product down on the page....

 

[troj]

We use something very similar when firing the bolts on our large projects.

I agree -- no relays. Use MOSFETs.

If you don't buy a commercial solution, make sure what you use will work with the firing circuitry on your altimeter. Output current and width varies between devices.

-Kevin

 

[stickershock23]

What type of batteries are you using?
I've been using the 9.6 volt rated.
It doesn't look like they have the 9.6 volt ones but these are close to it with 300 mAh VS 230.

https://www.thomasdistributing.com/-MAHA-9V-300-mAh-NiMH-Rechargeable-Battery_p_230.html


JD

Jd has the right Idea.

I am using a simpl Perfectflite timer with a Nicad battery pack. (6 old Makita cells) Nicads put out HUGE amounts of juice so they are perfect for this application.

Yes the battery pack is bigger and heavier, but if you are airstarting a cluster I am SURE you have enough power to lift a couple extra ounces.

I have lit as many as 6 First Fires in he air with this set up.

 

[alexzogh]

Fred,

Is Dave still around? I tried emailing a while ago about his booster droppers, but never received a reply.

IMHO -- using relays is asking for problems....
They can close unexpectatly under shake and shock....NO THANKS!

Use a solid state solution.
I found these Igniter Power Boosters from Dave Flynn.
They work GREAT!

See: https://www.dmf-rockets.com/products/index.html
See the third product down on the page....

 

[dixontj93060]

Any of you electronic wizards have a good relay design that would light multiple motors from a GWiz or other similar device?

I don't think a GWiz can light four ematches...I have gotten three to light, but four won't.

John at Transolve has a relay-based 10A booster board he sells with this Airstart board. He may be willing to sell the relay board separately.

 

[FredA]

Well -- I got a few of these units from him a couple of months ago...
No contact since then.
I assume he is around -- place and order

 

[ROCKet STAR]

Something like this?

https://wooshtronics.com/products-t110/clust-o-matic.aspx

 

[bobkrech]

The G-WIZ altimeters used 4 and 8 amp MOSFET pyro output transistors. Any well made high currrent MOSFET booster circuit will work, however you have to have a battery that will supply sufficient current.

In TRF 1.0 we had a good discussion concerning high current batteries. https://www.rocketryforumarchive.com/showthread.php?t=31425 Battery capacity in AH does not necessarily convert to peak current capacity. The internal battery construction (electrode area), not the chemistry, principally determines the battery's internal resistance, and therefore the peak current you can draw. Spiral wound cylindrical batteries have larger electrode areas than pancake cells so the generate peak current. Pancake 7 cell 8.4 and 8-cell 9.6 volt rechargable 9 volt transistor style batteries do not supply as much peak current as 6-cell 7.2 volt rechargables which actually contain 6 cylindrical AAAA cells in series.

Today, 2 or 3 cell LiPo battery packs offer the best peak current to weight ratio.

Bob

 

[MaxQ]

The G-WIZ altimeters used 4 and 8 amp MOSFET pyro output transistors. Any well made high currrent MOSFET booster circuit will work, however you have to have a battery that will supply sufficient current.

In TRF 1.0 we had a good discussion concerning high current batteries. https://www.rocketryforumarchive.com/showthread.php?t=31425 Battery capacity in AH does not necessarily convert to peak current capacity. The internal battery construction (electrode area), not the chemistry, principally determines the battery's internal resistance, and therefore the peak current you can draw. Spiral wound cylindrical batteries have larger electrode areas than pancake cells so the generate peak current. Pancake 7 cell 8.4 and 8-cell 9.6 volt rechargable 9 volt transistor style batteries do not supply as much peak current as 6-cell 7.2 volt rechargables which actually contain 6 cylindrical AAAA cells in series.

Today, 2 or 3 cell LiPo battery packs offer the best peak current to weight ratio.

Bob

Thanks for all the info guys....
I will read with great interest.


(oh yeah....my batteries on the GWiz?.......I had two fresh 9v lithiums hooked up, one for the device, one on the pyro channnel. I have a nifty double connector for two 9 volt batteries that I considered using - hooking up a double set of 9v the GWiz...using a third battery - ie. making two 9v on the pyro channel - but I didn't want to risk damaging the unit)

 

[JDcluster]

What G-Wiz nit are you using?
I e-mailed one of the guys at G-Wiz a while back & he said that you can run double 9volts for powering your altimeter.

If you run them in parallel you should be fine, as you will still be getting 9 volts.


The software update did help & doesn't drain the batteries when bench testing like they use to.
On some of the G-Wiz unit you can also set the length of firing time.


JD

Thanks for all the info guys....
I will read with great interest.


(oh yeah....my batteries on the GWiz?.......I had two fresh 9v lithiums hooked up, one for the device, one on the pyro channnel. I have a nifty double connector for two 9 volt batteries that I considered using - hooking up a double set of 9v the GWiz...using a third battery - ie. making two 9v on the pyro channel - but I didn't want to risk damaging the unit)