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9xtreme Reverse Current Protection Mod
Hi,
Before the 9Xtreme Upgrade Board for the 9x radios arrives,
I will do the Reverse Current Protection Mod on the 9x Main Switch Board. Cut Track and add SS34 Vishay DIODE SCHOTTKY 40V 3A SMC (http://www.ebay.com/itm/20PCS-SS34-Vish ... 2a5236986c)

MikeB wrote:The 9Xtreme has a processor controlled power switch for the Tx modules, so on the 9Xtreme, they will be protected by the single diode.
If doing this mod, I would suggest removing the 5V regulator on the switch board at the same time, it isn't needed anymore.
Mike.

(viewtopic.php?f=95&t=7182&start=270#p101974)
Mike, What do you suggest, that I should do to (disconnect CJ78L05) removing the 5V regulator on the Switch Board ? If you have SHUTTING DOWN screen message see: (viewtopic.php?f=126&t=7828&p=103935#p103847).
See here for other 9Xtreme information: (viewtopic.php?f=95&t=7182).

Bob B.

That's what I did. Since I was modifying the backboard I chose to remove the transistor and the buzzer as well!

Mike.

Hi Mike,
Should I then just unsolder and remove the 5V regulator (CJ78L05), Transistor (SC8050 D331)
and the Buzzer from the 9x Switch Board ?

I am not modifying the backboard.

Bob B.

yes.. And you can also remove/unsolder the transistor near the buzzer..

João

What about using a P-channel MOSFET instead of a diode?



Voltage drop should be much lower - which may be good if one is using a 2S battery...

(I used a similar solution in the 'PowerSound' module - and it works good)

That's a useful circuit, but not needed in this case. The soft power switch, which uses a similar reverse current protection circuit, shorts out the diode, so in normal use there is no voltage drop across the diode.

Mike.

Ah, right! Understood.
Thanks!

I have unsoldered/removed three components:
Regulator, Transistor, Buzzer and also I removed the old Antenna Contact Bracket. Next to cut the track I used a Dremel to grind it away. Soldered SS34 Vishay Diode Schottky 40V 3A SMC to Switch Board. Next to reassemble Modified Switch Board to confirm 9x radio still is working properly.

Bob B.

Problem ! No Screen at all now.
Radio seem to be powering up and screen has a quick flash of light.
No back light and no screen there is a beep from the transmitter.
Was working before.

Bob B.

The beep is probably from the RF module at power ON?

João

Double check the diode is the correct way round, and is fully connected to the two pins (switch and connector).

It may be worth a check with the diode shorted out to see if the radio starts then.

Mike.

I jumper around the diode and radio now powers up.
I checked another diode on the bench and I do have the diode in backward.
So I need to turn the diode around.

Update: bad diode had to use a different one.

Bob B.

I reversed the diode and it still dose Not work !
SS34 Vishay DIODE SCHOTTKY 40V 3A SMC (http://www.ebay.com/itm/20PCS-SS34-Vish ... rmvSB=true)

Bob B.

Test the diode with a multimeter. Maybe it is open circuit..

João

I'll try to do the mod myself this evening.

Mike.

Multimeter set to 2X OHM, 2nd diode reads: .539

There may have been a problem with the 1st diode because it is reading .265

Maybe I should turn the second diode around.

Bob B.

I turned the 2nd diode around like I had the 1st diode and Now it is working properly ! The first diode must have been a bad one.

My first 9Xtreme installation: (viewtopic.php?f=126&t=7718&start=90#p103320).

Thank you Mike and João !

Added João's Videos Jan. 31, 2016: Safe Power Switch: (https://www.youtube.com/watch?v=qzIZSg5U_6w)
and Safe Power Switch Battery Reversal: (https://www.youtube.com/watch?v=eFM2aSYPYYQ).

Bob B.

Good that is working..

João

Just received my 9xtreme.. i will be doing this shortly as well.. thanks for the posting...

While still waiting for my boards (even snails seem to be quicker than our customs )
I do prepair my 9Xs for them.

So I did the current protection mod with an alternative diode, the 1N5822.

Here 2 pictures that show how it can be installed:
(Also you see here an easy way to get rid of the buzzer and it's surroundings ... )
the cut track is clear to see...
The piece of isolation I strongly recommend ...

... next step is to put a drop of hot glue between diode and PCB ...

Klaus

You had no mercy cutting that board
I do think that the other screw add a little more support when operating the switch.

João

There now resides a rotary encoder ... I'm no friend of this centered neck strap supports.

This is my prefered solution:

Ahhhh, you're not a thumb flyer That explains everything

João

I can't picture it. What are the skis for?

Are you kidding me?
Klaus

Is the tray riveted to the radio??
Can't see very well on the pictures..

João

Just a 3 mm screw and some washers ...and yes, it's not built for blacksmiths ...

definitely not

This is my tray for the 9x

viewtopic.php?f=48&t=1454

João

Hi Klaus,
Sorry, but I am not able to see how the aluminum out riggers added to 9X radio with the strap are attached to a person for usage ?


Bob B.

In absence of a helper for taking a picture ...