¿ªÔÆÌåÓý

  1. BITX20
  2. Topics

CW key sticking with Nextion LCD ¡ª FIXED

Joe Puma
 

¿ªÔÆÌåÓý

So it¡¯s looks like I got to the bottom of the problem where RF seemed to be getting into the delay of the CW and causing chattering in my auto tuner plus a hiss in the speakers. ?

It was due to the IF out pan-adaptor wire I installed and when the wire In rear was plugged into SDR it seemed to allow RF to get in. ?I also changed the resistor I was using as a buffer and replaced it wit a 22pf. It seems not to effect the circuit better then the resistor. ?

Anyway I added 3 ferrites to the coax piece from my tap to the BNC connector on then back of radio. It¡¯s doing a good job keeping the RF out, that¡¯s what it needed. I also went through an exercise of replacing all wires with shielded cables, which all helps to keep the RF gremlins at bay. ?

I ordered some small ferrite rings to wrap any misc single wires but my problem seems to be resolved. ?


Joe
KD2NFC?


On Apr 12, 2019, at 8:35 AM, Jack Brabham - KZ5A <kz5a@...> wrote:

There is a uBitx "keying" board by W0EB on QRP Guys, might be relevant to your issue.



73 Jack KZ5A

 

I have found it interesting that toroids work when caps and coax don't work. Toroids are my go-to for rf noise.

I use these internally in radios A nextion display really benefits from them.

These on power cords and baluns.
and these around coax with PL259.

I bought 25 of each and thought that should last me a while. Ended up using almost all in 2 days. Shack noise when down a couple of S units. Wall worts have been particularly bad.
Joe Puma
 

Thanks for the links. I bought those exact ones when you posted the link. Yes I bought a pack of ferrites once thinking I only needed a few and ended up using the all and then needing to buy more. :)



73
Joe
KD2NFC

On Apr 14, 2019, at 9:32 AM, d balfour <davesters@...> wrote:

I have found it interesting that toroids work when caps and coax don't work. Toroids are my go-to for rf noise.

I use these internally in radios A nextion display really benefits from them.

These on power cords and baluns.
and these around coax with PL259.

I bought 25 of each and thought that should last me a while. Ended up using almost all in 2 days. Shack noise when down a couple of S units. Wall worts have been particularly bad.

1 - 3 of 3