Re: Ubitx V3 Please Help, ANTENNA Pins on PCB have SHORTED no Receive #ubitx #ubitx-help

Bill Cromwell

Hello Fabian,

If you trace the circuit from the antenna it will lead you through several relay contacts to an inductor to ground. That is a piece of wire that wraps around and around with or without a core. Your meter uses direct current to measure resistance and continuity. Direct current sees any inductor as a plain old piece of wire - a short. So it sees that inductor to ground as a dead short. At RF frequencies however, it is NOT a short. Most - maybe all - radios will have this:) So you should continue looking elsewhere for the problem.

Have you completed the "alignment" steps? If the oscillators are far off frequency the radio will not work very well if at all. Do you have a more experienced ham there who can help you?

Fabian, we all have or had different 'starting' places. It is not reasonable to assert that a kit is not for a beginner! At one time if hams did not make their own radios from scratch (not even a kit) they had no radio at all. The uBitx is not really so much of a kit. Building your own gear from scratch or from a kit is 'learning by total immersion'. Sometimes that method can seem frustrating but eventually we all get where we want to be. Just relax and enjoy the 'journey'. After you have finally sorted out the trouble and corrected it you will find it more satisfying than that Kenwood or Yaesu:) Those have their own rewards and can be an appropriate starting place for somebody else.

I started out building radios from a pile of old junk harvested from dead radios. At times it was discouraging but in the end it doesn't seem to have hurt me:)

And now about your English. Your English is very usable for a non native English user. I know only a few German words and not very much about the grammar or syntax. If I was suddenly transplanted to Germany I would experience 'total immersion' and would soon be speaking, reading, and writing German. It would sometimes seem frustrating but eventually I would fit right in :) For now your English is substantially better than my German.


Bill KU8H

On 08/25/2018 07:00 AM, sdr freak wrote:

My Name is Fabian and 31 years old from Meiningen in Germany and a have
HAM Licence Class E since 5 Weeks and my English is not the best so i
hope you can forgive me my writing and spelling mistakes and can
unterstand my problem. I need really your help and i i really thankfully
for any help so i can cry when my Ubitx receive at one day..

I have not much money and a have many health problems so a have only a
little job and can't buy a Transceiver like a Yaesu or Icom in this
price class.. My big Dream was to have a little SSB Transceiver for 80m
and 10m, bescause in Germany with my HAM Class E onky 160m,80m,15m,10m
are allowed.

So a other HAM from my town sell a Ubitx and i was very lucky to think
for 130€ my big Dream was come true.. He says its the best for me and
not really difficult to construct, only little bit of soldering an than
i can have my QSO a few our later.. So i trust him because i think its a
friend, but he knows that i was a beginner of HAM.. I do not want to
blame him, only I am a bit out of tune because many said a kit was not
for a bloody beginner.

But now to my problem..

I have been trying to get the transceiver running for a month but
unfortunately without success. I have tried many things including the
updates of the CEC versions and the Ubitx version v4 but all you hear
are rushing and sounding like digital beeping. I've also tried the audio
NF chip, the TDA2822 is the version FCI and does not seem to be the
problem. Then I tried everything again with other antennas and also
outside to avoid disturbances of the house. but again no success.

By chance, I then checked everything for short circuits and suddenly I
see with the continuity tester, the multimeter tester, between the 2
pins on the board where you connect the antenna cable, which has a short
circuit just these two !!! I did not know any further .. Then I was in
the Ubitx chat from the forum here and David said that's just not good
and that must be the error that I'm not receiving properly .. By the
way, thanks again to david if you read it, You are really nice and I
would like to say thank you again !!

that's exactly my big problem. I need urgently your help to repair the
antenna pin short circuit. I'm really really thankful for any help I can
do now or check something. or if it is possible that you had this error
before and know what needs to be repaired. I am really very sad to have
not had a single QSO for my test for ham... but maybe everything will be
alright, I always hope so...

I say thank you very much!

Best regards Fabian
bark less - wag more

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