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My uBitx with 5v mod #ubitx

Nigel G4ZAL
 

I have finished my build and modded it a little in readiness for adding additional boards/hacks.
I cut the track feeding the TDA2822 and fed it with 5v from a little Radio Control UBEC.
At the same time, I removed the 5v reg on the Raduino and fed that from the UBEC as well.
You can see from the pics, I added a little 'bus'. for picking off further 5v supplies as required.


Nigel G4ZAL
 

Here it is happily decoding FT8 on 40M via a cheap USB sound card/dongle.
Next step is the CAT control via the USB on the rear panel (connected to the Raduino) using KD8CEC firmware.

Joe Puma
 

Cool idea. I have a 5v regulator. I’m wondering if I can use it for a 5 volt supply in the radio and if there would be benifits to supplying tne Raduino too. But I was sure if my would create switching noise. I’ve tried to use it on my Mic (md- 100) for power source and got nothing but noise. But that might of not been the regulators fault.  

This is what I have below. 

Nigel G4ZAL
 

I used this UBEC @ 5v
https://www.banggood.com/Hobbywing-3A-UBEC-5V-6V-Switch-Mode-BEC-For-RC-Models-p-915037.html?cur_warehouse=CN

It has a small metal screen around it and the ferrite on the 5v output lead plus capacitor on the uBitx board (where I cut the track and soldered the 5v lead onto) forms an adequate LC filter on the 5v DC.
I can't detect any 'noise' on Rx, but as yet haven't transmitted.

I use the UBEC on model aircraft with a video transmitter (FPV) and don't see any noise in the signal.
The video transmitters are quite susceptible to 'dirty' DC and often shows as 'herringbone' lines in the received video.

Nigel.

 

Nigel,

Do a test. disconnect the unit from the load aka xBitx. Check the output voltage with the jumper not
installed. Like you accidentally knocked it off!!

If the voltage is more than 5 then hardwire the jumper and solder it. Better safe than sorry.

Raj


At 22-03-18, you wrote:
I used this UBEC @ 5v
https://www.banggood.com/Hobbywing-3A-UBEC-5V-6V-Switch-Mode-BEC-For-RC-Models-p-915037.html?cur_warehouse=CN

It has a small metal screen around it and the ferrite on the 5v output lead plus capacitor on the uBitx board (where I cut the track and soldered the 5v lead onto) forms an adequate LC filter on the 5v DC.
I can't detect any 'noise' on Rx, but as yet haven't transmitted.

I use the UBEC on model aircraft with a video transmitter (FPV) and don't see any noise in the signal.
The video transmitters are quite susceptible to 'dirty' DC and often shows as 'herringbone' lines in the received video.

Nigel.

Joe Puma
 

Thanks, I have a few uses for this if it’s RF friendly like powering my MD-100 Mic and since it’s used in FPV applications it seems like it’s right for the job. 


Joe
KD2NFC 


On Mar 22, 2018, at 8:53 AM, Nigel G4ZAL <nigel@...> wrote:

I used this UBEC @ 5v
https://www.banggood.com/Hobbywing-3A-UBEC-5V-6V-Switch-Mode-BEC-For-RC-Models-p-915037.html?cur_warehouse=CN

It has a small metal screen around it and the ferrite on the 5v output lead plus capacitor on the uBitx board (where I cut the track and soldered the 5v lead onto) forms an adequate LC filter on the 5v DC.
I can't detect any 'noise' on Rx, but as yet haven't transmitted.

I use the UBEC on model aircraft with a video transmitter (FPV) and don't see any noise in the signal.
The video transmitters are quite susceptible to 'dirty' DC and often shows as 'herringbone' lines in the received video.

Nigel.

Nigel G4ZAL
 

@ Raj,
Good question and I tested it out (whilst disconnected from the uBitx).
With the jumper completely removed, the output is 6v.
I suspect that moving the jumper to the 6v position is merely somewhere to 'park' it.

Quite how 6v would affect the Raduino, I don't know, but suspect it might damage it in the long term.

That said, the jumper is a good fit and I have never had one come off in some hard (crash) landings on model R/C aircraft.

@Joe
I have used these UBEC on a homebrew APRS, powering a Raspberry Pi, RTL-SDR dongle etc and never saw any ill effects.
They are cheap enough so won't break the bank if it doesn't work out.

Nigel.

m5fra2@...
 

Nigel, where did you get the case? It looks ideal.

Colin - G8FRA/M5FRA

Nigel G4ZAL
 

Colin, the case is an Excellway EF01 and is available from Banggood, ebay etc.
Ebay UK --> https://www.ebay.co.uk/itm/112584900985

Nigel