BITX40 Click problem

BevTed Stanier

Hi Allard,

Tried different wall warts, one of which I installed a voltage regulator chip. None made any difference to the thump. Tried a battery with no change.

Believe I saw a suggestion to put a cap on the volume control but it also made little difference.

Found a mod by VA7AT that works on the BITX40 and the uBITX  and uses 3 mosfets plus. Don’t anticipate going that far.

This BITX40 was given to me and I have put very little into it except time. I have an Icom 718 so don’t really need a single band transceiver. The purpose was to learn and enjoy the hobby. I did not buy a case and my wiring is a mess. I have learned a little about SMD, C++ etc. So I call it a success.

It works so maybe I’ll give it back. Hi.

Thinking about test equipment if I could fine some kits.

Thanks again for your help.

73 Ted


Sent from Mail for Windows 10


From: <> on behalf of BevTed Stanier <bevtedstan@...>
Sent: Monday, September 21, 2020 11:32:21 AM
To: <>
Subject: Re: [BITX20] Ardunio nano D7

Thanks Allard

Fixed my p-p v output problem. Another  self caused problem.

Now I can move on to learning about software for TX_DELAY. Wish me luck as my learning curve gets steeper. Hi


73 Ted


Sent from Mail for Windows 10


From: Allard PE1NWL
Sent: Sunday, September 20, 2020 12:52 PM
Subject: Re: [BITX20] Ardunio nano D7


Hi again Ted,

so it seems you're getting back on track, good!

As for the RX-TX burst:
The firmware has a built-in TX-delay to prevent the spurious burst - the default delay is 65 ms but you may want to experiment with slightly higher values.
In that case you can edit line 80 and recompile and upload again:

#define TX_DELAY 65 // delay (ms) to prevent spurious burst that is emitted when switching from RX to TX

73 Allard PE1NWL