Hi guys

I am in the process of installing a Tamjets failsafe in a Weatronics rx and in a conventional receiver using 2 channels - one for gear doors and other for gear train.

How can I set-up the Tamjets gear fail safe with 2 channels. This device as a plug hole for gear servo and if you are using a sequencer (with only one channel) it is clear, but how about if you are using 2 channels as described?

Regards

Nuno

I can't think of an easy way to use the Tamjets failsafe as you describe but you might be able to work around it.

Bear with me as I might be talking rubbish here but

The only way I can see that you could get the failsafe to operate 2 channels plugged into the Weatronic is if the output from the Tamjets failsafe is input to the receiver. The only 'input' that I am aware of, is through the gyro function. In this case the Tamjets failsafe would replace the gyro. I am not sure if you would be able to set up the sequencer function in the RX like this though.

I personally think that, if you want to use the failsafe, it would be much easier to use a separate sequencer.

I wonder if you could setup the Tam sequencer on a separate channel and then mix the channel with your gear switch so that if the Tam unit goes into failsafe then the mix would activate your gear? Have you called Tam yet?

What valves are you using for the doors?

You can't, they are single channel. IF both channels can be activated at the same time without delay/sequencing then you can plug the second servo into the AUX port on the unit, but if this were the case, you'd only need one valve in the first place


[sm=confused.gif] the Tam failsafe is activated via air pressure, has nothing at all to do with the radio failsafe system.

Thanks for the imputs.

In my F16 I have set up like the one in the attached photo. There are 2 servos driving 2 airvalves, in 2 different channels that have a mix with delay in my Futaba 12FG.

Also I was planning to install one in my F18 with Weatronics rx that as 1 channel in use but an internal mix in the Weatronics receiver with a master/slave with delay between each other.

From what I have understood the Aux in the Tamjets can be plugged to the doors and the rx plug to the gear. If there is a pressure drop the signal will be invoiced to both channels. The delay in the mix might retard the gear to open after the doors???????

Also I have the latest version of Tam's with firmware upgrade. This is not clear because from wht I understood from instructions is that I can operate brakes as long as I have gear down[&:][&:][&:]

Tam, some help would be appreciated

Regards

Nuno

No the delay is via the transmitter it isn't the servos that are slowed, it's the signal the transmitter is sending to the receiver, when the failsafe feature of the gear reaches it's set low pressure the servos move at full servo speed.

if you have the brakes mixed to the gear (such as on the Flash) with the new firmware the servo will move within a set limit allowing the mix to turn brakes on/off, the gear switch has to be in the DOWN position for it to work. you can test it by pumping the pressure up till the gear will retract, with the gear retracted press the fill valve allowing air to escape, when the failsafe kicks in and drops the gear, moving the brakes will do nothing, flip the gear switch to DOWN and then the brakes should work. I've got the newest firmware on both mine and they both work as advertised.

when using the brake mix I've found one thing out, i have mine on my Flash set so when the failsafe kicks in it drops the gear and puts the brakes on, because of this when i power up the receiver with the transmitter in brakes OFF the brakes will not release till I've placed the brake switch in the brakes ON position for about 2 seconds, the failsafe unit boots then and will allow the brakes and gear to function.

KC,

Thanks for the support.
You need little Tamlish to add ice on the cake.

I'll work on it, but to tell the truth, as many times as we've spoke i completely understand your every word and always have so i don't pick up on it like the left coasters do, Tamlish must have a little southern draw to it.

Now that's FUNNY y'all!! [&:]

Hi Nuno:

I have installed in my Skymaster F-16 1/8 the Air Micro Switch from BVM (part No.: BVM # 5753 at USD $ 27.50).

You can find it at:

http://www.bvmjets.com/Pages/Catalog/air.htm

I have also installed the Tamjets Gear Fail Safe and it have been working very nice. I have set the activating pressure in 50 pounds. After the gear is retracted, the strut push the button in the swicth through the lever and air flow to the doors cylinders closing them.

When gear is extended, the strut release the button of the Air Micro Switch and gears and doors open simultaneoulsy.

Regards

Guillermo

the trigger valve is an OK cheap way to work doors But I've found it only works reliable when you've got a forward retracting gear that you use for the trigger strut. the air pressure in flight on that gear slows it down from retracting so all the gear have an opportunity to get up and tucked away before the switch is pressed, otherwise it's luck of the draw and if the trigger gear happens to not be the last gear up then the doors close on the other gear.

It operates the gear servo when it senses low airpressure right? so why couldn't you mix that signal on one channel to operate another channel (i.e. the true gear channel) when it is sent a movement signal. Maybe the radio being used cannot handle it but it is in theory a very simple concept.

The problem here is that the Tam unit bypasses all programming in the radio and goes straight to the receiver from what I understand so in that case this wouldn't work since it relies on a transmitter mix.

Also for the trigger valve you can just use an airline restrictor to control the time when the strut hits the valve.

the failsafe unit is located IN THE AIRCRAFT, it simply drives the servo, it's can't induce a mix IN THE TRANSMITTER.


no it doesn't, it learns the programming of what gear down and gear up are and what pressure you set it to activate at, it does exactly the job it was designed to do.

i'm gonna go out on a limb here, you don't have one????????

Actually I do KC, had one in my F-16. And if you read my post I added the fact that the transmitter is excluded. Thanks for being so concerned though

I dont use them anymore thanks to this little guy:

in reply to the PM, No i don't.

in reply to your above quote, you said previosuly:


the failsafe unit goes between the receiver and the servo, it doesn't bypass the transmitter and go straight to the receiver, it simply removes the signal the receiver was sending to the servo and sends it's own 'Gear Down' signal (that it learned from the receiver during programming) to the servo when air pressure drops below the set limit. with the new firmware if the signal from the receiver matches gear down then it'll allow the servo to be commanded by the receiver again for brake function but not gear up. if the pressure is returned to above the limit by 25 PSI then it'll allow gear up again without reseting the unit.

"the trigger valve is an OK cheap way to work doors But I've found it only works reliable when you've got a forward retracting gear that you use for the trigger strut. the air pressure in flight on that gear slows it down from retracting so all the gear have an opportunity to get up and tucked away before the switch is pressed, otherwise it's luck of the draw and if the trigger gear happens to not be the last gear up then the doors close on the other gear."





I use the buttons for the nose gear doors on most of my BVM sport planes, and find they work perfectly only if you slow the gear servo way down, like 4-5 seconds transition. This would not work for the electronic valves, of course. If you don't slow the servo down, you are absolutely right about snagging a door.

Ooops! I mis-spoke there. My KC and ARF Bandit use normal servo speeds and the N/G strut contacts the button. When the gear is coming up, the door must stay open until the strut is fully retracted, and when going down, although gear cylinder and door cylinder are opening simultaneously, the small volume air cylinder pops the door open faster than the gear cylinder can pull the gear down.

On my BCARF with the eccentric arm that is driving the button, then the servo must be slowed down to work. Same deal on other planes I have had with the button pushed by the BVM or similar retract cylinder.

Essentially the transmitter is out of the picture so mixing will not work and that was my point.

Sounds like you maybe S.O.L. with 2 servos Nuno, but on the other hand you got tons of suggestions on how to make it work other ways[sm=thumbs_up.gif]

Tom

i've never used the trigger valve activated with the servo horn before just the strut, with a servo slow feature that seams like it would be fairly easy to get by with just one servo on just about any application.

I use triggle valve on my Hornet, F-16 and almost anything that had door open gear down, gear up door close.
The trick is you got to set it up right. Any pressure on the strut will get stuck or too loose it bleach out the air slowly in flight.

The other way is like Tom did on his.
Delay the travel on the servo and with little mechanical delay it works like a charm.
Here is the set up I do to have retract, doors sequencer and brake all in one channel and servo.
This is cheap set up and it's just work everytam.

That cam setup idea I originally got from Tom Dodgen and Barry West.....once you get the dimensions right ( I used up 3 or 4 of the round arms which I seldom use elsewhere) and get the hole placement right, it is perfect. I had the room on the BCARF for a small extra air tank, so the doors are isolated from the gear air supply, although it is simple to hook it all up to the gear tank. That is the way I have it on the KC and BARF. I have Tam's FS Unit on the BARF as well. Once I figured out how to get the setup to work right on 2.4 with no jiggling of the gear servo or folding of the gear when I turn RX on, it was [sm=thumbup.gif][sm=thumbup.gif].

Paul Hopkins used to set up his gear with a button valve between separate air and door tanks. He controlled it with just his gear servo by putting in a mix with Aux 4 or 5 that slightly moved the output arm over center, contacting the button. That way, if he lost air in his gear tank, he could transfer air over from his door tank, just enough to at least get the gear down and locked, but Tam's FS has made that system obsolete.

did you find binding with the gear in the UP position fixed your problems? or something else? the gear UP worked for me.

KC,
You the man. You beat me to it everytam.

no problem big daddy but you have to love Ian long time to make him feel better about my earlier post, didn't mean to ruffle his feathers.

Thanks guys....

Ok. so following this idea it should work with the weatronics, because the mixing is in the receiver and it uses a master-slave mix with only one channel.

Well, I just have to plug it and play arround a bit

Regards

Nuno