Bendix Ignition Exciter questions

[madpatty]

Hi all,

I recently bought this used Bendix ignition exciter, labeled as a 10-30V DC unit.

Here are some pictures for reference:








I have a couple of beginner questions:

1. Where should the power leads be connected, and where does the ignition plug go?
2. I attempted testing it with a 6S (22.2V) LiPo battery connected as follows:
- Positive to the inner lead and negative to the outer threads:


For spark- Two wires connected between the inner lead and the outer casing/threads:

However, all I got was a constant humming sound from inside the unit, and no spark was generated. Is there a more effective way to test the exciter?

Any advice would be appreciated!

Thanks!

[richardm]

I can't answer all your questions . But first of all this is not a toy. It can deliver a very nasty shock that could kill you if the eletricity path happens to be just right.

Many of those sold on E bay and the likes are unserviceable. Quite often because of a bad discharge gap tube. See the radioactive label ? Thats what it is. I believe the radioactive gas in the tube decays overtime.
These devices are not used anymore .


I not sure either if it works fine without the proper spark plug connected. And you will need the cable that fits the unit . They have some weird thread 3/4 x 20 if I remember .

Good luck

[finiteparts]

Agreed with Richard...be careful as the energy this can create is sufficient to stop your heart.

Testing these without the proper connections is a great way to destroy them. I do not have any information on that specific type of box, but similar Bendix ones do hook up like you have shown. As and example, I saw one blow due to forgetting to tighten the fully tightened.

My guess is that this box is for a standard gapped type plug, but if it is meant for a semi-conductor tipped type plug, then the initial pulse required to ionize the gap is much reduced relative to the non-semiconductor type.

I would invest the time getting a similar type cable and ignitor to test it with...anything else might destroy it.

There are only a few styles of connections, but I don't have access to the SAE document right now. I might be able to find it tomorrow and share the standard type of plugs and connections.

- Chris

[richardm]

I did a quick search about the spark gap that is more than likely sitting in this box. They contain CS 137 (Cesium 137) In minute quantity thus the radioactive label. It is used to ionize the space between the electrodes inside the spark gap tube. CS 137 has an half life time of about 30 years. Looking at the attached tag dated 9/ 25 / 87 it tells that it has been in storage for 37 years now + all those years since it has been manufactured.
I would say your box is 50 to 60 years old and the Cs 137 way passed its useful ionizing capacity making the unit unserviceable.

Just to say CS 137 is also used in some smoke detectors and its rather short half life is why it is recommended to change those detectors after about 10 years.

This is just my opinion. It is now up to you to decide in investing more money in a suitable cable and spark plug.

[madpatty]

Hi Richard and Chris,

I completely agree with you both regarding the safety risks involved. It’s definitely not worth the headache, especially since it's pretty much a lost cause at this point. I'll likely look into getting something with the proper leads and a compatible spark plug to avoid these issues.

Thanks for your input!

Patty

[richardm]

Sept 29, 2024 9:26:17 GMT -5 madpatty said:

Hi Richard and Chris,

I completely agree with you both regarding the safety risks involved. It’s definitely not worth the headache, especially since it's pretty much a lost cause at this point. I'll likely look into getting something with the proper leads and a compatible spark plug to avoid these issues.

Thanks for your input!

Patty

I m sure you know that you can make your own pretty decent igniter from an HV generator an HV diode and a microwave capacitor. 
Heres mine: