I did not intend for this to turn into a bash of the UP6. I think it is a good brake valve. Mine worked well for a couple of years before developing a problem. My point in mentioning the UP6 is that any of them can have a problem. If a problem develops, hands down the SS is the simplest one to service.

Some one mentioned a Trim valve. I forgot that I also have one of those, but have not used it. If I were having the kind of trouble with the SS mentioned here, I believe I would have installed it by now.

I think my equipment does get more of a workout than most because when the Miss. Gang goes jet flying, we fly relentlessly. I simply like the way the Smooth Stop works better than the others. Any needed maintenance is easily and quickly performed at the field if necessary. I do hate to see a good product get bashed by a few people who may not have had as much experience as we have had. There are eight of us in the Mississippi Gang who fly, including my two sons and Rick's two sons. That is eight of us total, and we have a LOT of jets. They all use the Smooth Stop, even my non BVM jets. If we had the kind of problems mentioned by the few comments here, we would have changed a long time ago.

Best regards to all.
Dennis

Tom,
If the above is correct and the valve uses air in the full on position then that is not an improved valve. The older and larger black valves that you mentioned did not use air in the full on position, only time air was being used was either between the on or off position.

I prefer the jettronic valves over the up6 or the SS I just consider them much easier to use, setup and whole lot less maintenance. I did have a smooth stop once and I could not get the darn thing to quit leaking air. It was too finicky for my tastes. The other thing that I really didn't care for was the price, by the time you bought the smooth stop and the servo to operate it you were well over 100.00 for the set. The electronic valves are one nice neat package that is ready to install.

This is just my opinion, and I hope no one considers it bashing of the SS just because I did not like it.

Patrick

I have the new valves, and as far as I can tell there is NO air being vented when the brakes are in the full-on position - pulsing happens only in the range of 10% -> 90% on.

Gordon

If dirt is a problem with the smooth stop, what about putting a one of those rubber pushrod exits for boats or something similar over the valve opening to keep the dirt out?

Chris

That is correct

Patick and Matt:

You guys are right. My brain fart. Been using one of the old ones on my HotSpot for 2 years.....dah!

I just set one of the new Jetronics units up on a club member's ARF Roo this morning. It stops pulsing with full on just like the old ones.....It is rather cool with about 1/2 the footprint of the old one. The programming steps are improved as well.

I haven't yet played with restrictors on the outflow port, but it appears with the right restriction, one may be able to crank in partial ON, say on downwind, and not loose too much air before touching down, thereby changing the degree of braking... Reproducibility of air pressure is important, since if you calibrate the partial setting with say 120PSI, and then by the time you touch down, it has dropped to 40, the brakes will no longer hold.......at least with BVM brakes....

Hey Dennis....We've been friends for a loooooong time! It wasn't my intention to irritate you. There is more than one way to skin a cat concerning getting our jets stopped. I was just relaying the experiences with my (and Ed's) Smooth Stops. I was going to ask for a group hug but I don't think any of us can get our arms around David any more....

Kevin

Well Kevin, I guess I should stay off the internet because it seems I sure don't know how to convey my ideas without seeming like I am on a tear about something. No offense has been taken. I am a very straight forward type person, still, my charming and genteel personality has won me many friends and influenced many people, just not by the internet!

I'm not even going to think about making another comment concerning brake valves.

BTW, when are we gonna see you at a jet event again. I thought for sure we would see you at Tennessee Jets just down the road from you.

Dennis

Dennis,

I'm going to send you a PM concerning missing your event and Tennessee Jets. I hate that I missed both....However, I will be at Superman!!!!!

Kevin

by any chance does anyone have a picture of the new Jettronic brake and retract valves next to something for size comparison?

I have yet to see the new valves in person and was just wondering how small they actually are.


Thanks

Patrick.

I thought there might be a pic of the laest valve on the Jetcat web site - but unfortunately their we site is not working properly right now - you get an internal server error of you try to access the pages for the brake valves.

If no-one else posts a pic today, I'll try to take a photo of my Jettronic brake valve when I get home. Ballpark estimate going from a frequently fault memory - main body of the valve is maybe 1.25" square and 1/4" thick, then it has a "foot" at the bottom for mounting, plus festo-style connectors sticking out in 3 directions. You do need special 3mm airline for it though - "regular" airline will not fit.

Gordon

Gordon,
A pic would be great. I already have some of the black valves in my planes and wondered how big the new ones were in comparison. I am planning the installation of all my equipment in my bobcat and just wanted some idea of sizes.

Patrick.

In another thread, the one related to ram solenoids, there is a website that sells pneumatic valves. After extensive discussion with their people, I've found that these valves are suitable for our applications (both retract and brakes). The cost is something like $25.00 for a brake valve (fully proportional) and $25.00 for a retract valve (fully proportional or on off/ for robart or spring air).

I wouldn't all jump ship and start making the calls yet, I'm ordering some for testing in my kangaroo. Should have all operational in a couple of weeks and I'll post my results on RCU.

I forgot, I do have a question that someone here may be able to answer. If I have a two wire device such as a proportional brake valve or an on/off valve. Would I hook up the negative wire from my receiver and the signal wire from my receiver only? Consider that I'm on a 5 volt battery system and the device is 0 -5 volts. It seems to me that I would hook up the proportional signal from my receiver, assuming it is a 0 to five volts originating from my transmitter. You guys see what I'm saying? If not, I'll try to clarify.

Maybe I'm misreading, but you seem to be assuming that the signal wire will show a voltage proportional to the control position ? (Rather than it carrying a signal whose pulse width varies from 1 to 2 ms)

Gordon

Holy Crap, I was! Are you tellinig me that if I put my volt meter on the signal and negative, I'm gonna get a pulsed signal of the 5 volts?

You have a 50 hz, repetitive pulse train, with a variable duty cycle signal. No telling what you will get if you just hang a voltmeter off the signal (just some average voltage), but with an oscilliscope you can see it

The "on" pulse width varies from about 1 msec to 2 msec.

Servos have worked this way for about 25 years I would guess

The valves that jettronic makes have a small computer in them that can interpret the signal, and allow you to program the linearity of the of the braking system to a certain degree.

The computer has an output to control the valve, and it is a bit smaller than the valves we sell for the turbine shut off valves

See http://www.rcuniverse.com/showthread...86#post1077600 for a nice little pic showing what kind of pulse you should expect to see on the signal wire.

Gordonn

What about in ON/OFF application. If you put the servo on a switched signal, do you get Zero volts signal and 5 volts on the on off? Or is it again a pulsed signal? In that case, is there a microprocessor on board the servo taking the pulsed signal and changing the rotation accordingly. I understand that if that's the case. That would then explain why the minihobbies brake valve has a control board attached to it.

Still pulsed. (Otherwise you would need different types of servos depending on whether you were connecting them to a proportional or a switched channel)

If you want to get simple on-off operation of the valves you bought, then the simplest way might be to add in a cheapie servo that drives a microswitch that allows your RX battery voltage to be switched to the valve .

By then tho, you have a "solution" that is more expensive than the Jettronic valve, but is providing less functionality... or to get proportional behaviour you could have a servo drive a pot instead of a microswitch

Or if you are comfortable enough with electronics you could throw together a converter to take the incoming signal and generate a proportional 0 -> 5v level out of it... there may even be a commercial product out there that does this for you.

Sometimes it's just easier to pay someone for the product they already have Maybe less fun though.

Gordon

That is what the little box is on top of the valve section. It has the programmable computer in it.

The long dimension of the top of the valve is about an inch I am guessing.

And the website is undergoing some maintenance, sorry for the inconvenience

Well, right about taking the fun out of it, but got the education that I was looking for. Thanks guys. I thought I was on to something, but looks like cost vs. time vs. the unknown factor, you're right, just go with standard available products. You should have seen my eyes when I showed him the minihobby site and he said "we make that valve for them".

It's definitely smaller than the black one.

Pic attached. Measurements of the rectangular "body" is just over 1" ; height is just under 1" ; thickness 3/8". The base sticks out just over 1/8" extra. Total footprint including the Festo-type connectors is 1 1/2" x 1". To that you must allow some room for access for the airlines (for the next generation valve, it might he handy if they were to to put all 3 connectors on one side, so that you don't need to account for some room on 3 sides of the valve).

Gordon