www.pulse-jets.com

I have built my own concept with concentric intake, only remotely similar to Tharratt. The engine run very strong with little of forced air, without it, quits. ( It has "perfect" concentric intake, intake area was calculated as 22% of CC area ) Than I started tinkering with it - like bigger intake f...

Im also working on a set of plans for a super valveless which will hopefully revolutionize jet speed control line flying..... I need some people who want to make some prototypes.... but that is for another thread. Eric Eric, I would be much interested in building couple of prototypes. I am working ...

Im also working on a set of plans for a super valveless which will hopefully revolutionize jet speed control line flying..... I need some people who want to make some prototypes.... but that is for another thread. Eric Eric, I would be much interested in building couple of prototypes. I am working ...

Bill,

We want Pictures ! We want Pictures ! We want pictures !

Info about delay line is not related to liquid fueling.
Just hybrid rocket motor issue.

Francisco,

Quite a collection !

Do you have any archive with data sheets and performance notes?
( Assuming, all these babies run )

Ed

I heve been trying to attach short video clip without success.
The file gets uploaded ( at least it looks like that - takes quite a while )
after it finishes original message has no attchment shown.

Where is the problem ?

Ed

Need help from any of you, electronics gurus ! Would anybody help me design delay line curcuit for 6 to 12 volts and Time delay 4 to 6 seconds. Ed: Just Google for "time delay relay", and you'll get more than you need. Here's an example: http://www.electronics-lab.com/projects/misc/014/ --this conc...

Ben wrote:You have a beautiful daughter, Bruno; congratulations to her and her team. It sounds like a great trip, and you've sold me on Prague. Maybe I'll make it there in a year's time.

Bruno,

Ben needs a new girlfriend.
( Ben is very nice and smart young gentleman - you better think about it )

Ed

Hi Ed, What You need is a Schmitt trigger. One pulse is stretched to the desired length, and only repeats when You apply the next pulse. I use the 7400 series IC's which are robust and very cheap. I have included a 555 timer based circuit in the attachment. Al Belli Al ! You made my day ! Thank You...

Need help from any of you, electronics gurus !

Would anybody help me design delay line curcuit for 6 to 12 volts
and Time delay 4 to 6 seconds.
I nedd to charge a gas selenoid and keep it open ~ 5 sec, after 12V-DC
gets disconnected.

Any suggestions are very appreciated.

Ed

OK, Larry, From now on, no more paper engines - everything must me METAL. That will teach you !!! :-) Ed Next time try air nibbler or 4in grinder with cut off wheel, in both cases distortion will not be a problem. If I cut in small triangular sections, I can cut some very tight curves nice & smooth...

I agree that straight pipe charging the CC is the best way, also expansion back to intake is more efficient. From the construction point of view, Larry's idea is pretty sound. Perhaps make that spout as flat as possible. Your objective is minimazing drag and it is not clear if it is good trade off f...

Bruno, I wonder if you saw aircraft engines exhibition. That is realy incredible, all WW II engines and probably most interesting prewar radials from 3 to 9 cylinders ranging from about 25 to 200 HP. Most of them were original Czech Walter engines and these were made as Swiss watch. Incredible machi...

Ok lets ask a basic question that I think Bruno addressed but may have slipped by peoples notice. Were is the point on the air frame were it is best to have thrust applied? Bruno pointed out on a hang glider it was at the centre of gravity for the whole set up ie the pilots position. Forget the eng...

Super !

Looks like you are in serious production.

Ed