Featherweight 24mm Av-Bay - Magnetic switch LED Lights Up but Blue Raven Does not Boot

[kjhambrick]

All --

Probably a question for @Adrian A but I am throwing it out to the world for input.

I was gifted a Featherweight 24mm Av-Bay back in October by TRF Member @Worsaer ( thanks Bill ! ).

I finally finished a 3-inch by 24mm coupler for Bill's 24mm Av-Bay so I can fly the Blue Raven in a 24mm rocket on small motors.

When I assemble the Av-Bay and try to boot, the blue LED for the Mag-Switch lights up ( on solid ) but the Blue Raven does not power up.

Are there any areas I should inspect for damage on the Active End ?

Are there any tests I might perform to diagnose the issue ?

Thanks !

-- kjh

This is the 30-gram Featherweight 24-mm Av-Bay in "La Niña Vulcanita 24" :



The threaded rods are 3.5-inch #2-56 316 stainless steel ( Austentic so it is non-magnetic )

Nuts and washers are #2-56 18-8 stainless steel ( only very mildly magnetic ).

The center coupler is a 2-inch section of Semroc SEM-CPL-50-4 which holds the Blue Raven.

There are forward and aft 0.5-inch sections of Semroc SEM-CPL-50-4 with SEM-PB-50 stepped bulkheads to provide hard-points for the main and drogue shock cords and to provide a place to connect ejection charges.

The same 316 stainless steel rods and the nuts and washers work fine in similar 29mm and 38mm Featherweight Av-Bays that I've finally got ready to fly.

This 24mm Av-Bay looks so cute and it weighs only 30 grams fully assembled.

Now if only I can get it to boot the Blue Raven I'll be much happier !

 

[manixFan]

On mine, I have to seat the battery pretty firmly to make sure it is making a good connection. If the blue light comes on but no joy on the altimeter, make sure that the pins from the AV bay are completely inserted into the header on the Raven and then tighten each screw down and verify you have them nice and snug. And of course check the voltage of the altimeter battery. Otherwise, try a different Raven and if you get the same results, you may have a bad AV board. I had one that had been crashed and while it looked fine, it no longer worked properly.

Good luck – I hope it's something simple.


Tony

 

[kjhambrick]

On mine, I have to seat the battery pretty firmly to make sure it is making a good connection. If the blue light comes on but no joy on the altimeter, make sure that the pins from the AV bay are completely inserted into the header on the Raven and then tighten each screw down and verify you have them nice and snug. And of course check the voltage of the altimeter battery. Otherwise, try a different Raven and if you get the same results, you may have a bad AV board. I had one that had been crashed and while it looked fine, it no longer worked properly.

Good luck – I hope it's something simple.


Tony

Thanks for the input and ideas, Tony.

Yes, tightening the Blue Raven terminal block screws 'tight enough but not too tight' is essential.

I was thinking about this last night and ...

I was wondering if it would be worthwhile to try the Active End with my Blue Raven without any rods and nuts.

I only have one Blue Raven for now ( until I order two-or-three more later this week using @Adrian A's new Blue Raven volume discount calculator ) ...

My 29mm and my new 38mm Av-Bays both work.

But my 38mm Av-Bay is inside an AT 1.9 inch coupler, being set up for this month's launches in an old rocket ( "Casi un Vulcanite" ) that used to fly an AltAcc.

I'll try the working 29mm Active End -plus- my Blue Raven without rods and nuts.

If that works, I'll check out the 24mm Active End, especially the (+) and (-) battery connections:

Note: This image was stolen from the Featherweight "Quick Start Both Sides" PDF, cropped and converted to .PNG ( edit: via The Gimp )

I've got some small probes for my VOM that will fit so I should be able to check the voltage at the top of the (+) and (-) set-screws and then check for shorts among the other set screws...

That's a start !

Thanks again !

-- kjh

 

[manixFan]

I would do exactly as you suggested with the active end without any other connections. That 24mm AV bay is so small that it is easy for a washer or nut to make contact with something it shouldn't. It's good that you have the other larger versions that you can verify operation of the Raven with the active end so you know the battery is ok. On the active end that I had that was bad, I finally saw that it was just slightly bent and a couple of components must have lost contact with the board. I still have it and may look at it closer one day, but I have several others that work fine so I figured I did not want to risk it.

Small is good, but small can be a pain sometimes!


Tony

 

[kjhambrick]

I would do exactly as you suggested with the active end without any other connections. That 24mm AV bay is so small that it is easy for a washer or nut to make contact with something it shouldn't. It's good that you have the other larger versions that you can verify operation of the Raven with the active end so you know the battery is ok. On the active end that I had that was bad, I finally saw that it was just slightly bent and a couple of components must have lost contact with the board. I still have it and may look at it closer one day, but I have several others that work fine so I figured I did not want to risk it.

Small is good, but small can be a pain sometimes!

Tony

Yes, I am learning that smaller is A LOT harder !

I just now tried the 24mm Av-Bay without the rods and nuts and it still lites up the Blue Mag Switch LED but does not boot.

No joy !

I decided to moved on -- "Casi Un Vulcanite 48" is ready to fly with a 38mm Featherweight Av-Bay.

And next, I'll finish installing my 29mm Featherweight Av-Bay inside a BT55 Coupler for "La Pequeña Vulcanita 34" and get her ready to fly.

At least I'll have two new rockets with Blue Ravens in Featherweight Av-Bays ready to fly ( CUV-48 and LPV-34 )

And instead of moving down to the 24mm "La Niña Vulcanita 24", for my next trick, I'll kick it up a notch to a new Mach 1 BT60 "La Diminuta Vulcanita 42" with the 38mm Av-Bay and then down to "La Media Pinta Vulcanita 29" an Mach 1 min diameter 29mm Vulcanite.

Dang ! I have also learned that I was completely spoiled by the 'slap it in and send it' installations for the AltAcc

But I'll tell you what, the Featherweight Av-Bays are almost perfectly axially balanced right out of the box which will probably matter with these small 3-finned rockets that tend to roll a little in the Texas Prairie winds.

Thanks again, Tony !

-- kjh

p.s. Double Dang ! I already placed an order with Harry for some RMS 18/20 seasonal motors !

No worries, the D2.3T motors will 'keep' until I figure out a way to fly the Blue Raven in a 24mm rocket

 

[manixFan]

I still have a couple of AltAcc altimeters, but last time I checked, the baro sensor on one was kaput. But they were easy to use. I also was conditioned to always use a new 9 volt battery with those, and that has stuck even with new ones that use far less current.

Old habits die hard.


Tony.