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Hi there, I've been seeing posts about burnt finals, melted transformers, etc. Is there a way to "invest" into parts for the sBitx V3 to make it more resilient. I would not mind to buy beefier

?Je to dobrá zpráva pro v?echny ?ekající. Není pot?eba kolektiv HF Signals nutit ke spěchu. Dělají, co mohou aby v?e bylo v po?ádku a osazení desek, kompletace a testování se nedají

I have finally disassembled my sBitx fully and removed final MOSFETs.? I have to cut the away to not damage the PCB. One of the was still alive (so I'll probably use it for prototyping): But the

No documentation was sent about any changes to the v2. What happened was that the devices sent in April 2023 did not come with any information sheet, so on May 3rd, several messages came, which can be

Hello Evan, I tried that yesterday, and found that the resistance remains below 1 k. Another fact was that the DC voltage on gates with power, at minimal drive and PTT on didn't change as

Wojtek, I suggest verifying that adjusting the PABias1 pot does change the voltage on the MOSFETs' gates.? As Gordon stated, you need to be careful when making this adjustment.? It is very easy to

Either port will power it up.?? Data only on the inside port. Dom /*========================================= */ /*On 2/28/2025 5:10 PM, David T-- VE3TOS via groups.io wrote: */

The strange thing is that performing the bias regulation (as described on the website) I couldn't get the increase by 200 mA in the whole range of regulation. May the transistors be partially

Those two diets you were talking about are not normal diodes they are transient voltage suppressors. They won’t conduct until the voltage gets around 10 V. Be very careful with that PA bias. You can

be certain that you have correctly identified the PA bias potentiometer. It would be very odd if turning that too far didn’t destroy the MOSFETs when you press push to talk the voltage on L 80 and

In my board I have additional diodes D8 and D9 connected between the gates of Q16 qnd Q17 and the ground. It seems that the voltage delivered by the bias circuit is limited by the those diodes to 270

JJ, I agree with Gordon's suggestions.? IRF520 would be a more robust part, and the TVS protection is a good idea as the driver circuit can deliver higher than the gate voltage if driven to full

I have one interesting finding. It seems that changing the PA_BIAS1 setting does not modify the current consumed by sBitx. After pressing PTT It increases from 0.31A to 0.77A, and does not depend on

one of the ports is for power, I don't think it provides data. [email protected]> wrote:

Unknown. I heated the end closer to the back of the PCB, and the cap fell right off the board, with a end still on the PCB. A check of the cap shows it is open, not surprising with the end

If C202 (47pf) SHORTED, you would expect potentially what is being seen. If the 80 meter filter were invoked, and your frequency is above that, the input of the filter might act like a short. If D15

Interesting why it cracked/failed... due to mechanical stress, like bent of PCB... temperature shock...? or was it already bad since new...

I hope so, you guys have been absolutely great! Stay tuned. 73, Richard AG5M On Friday, February 28, 2025 at 02:19:21 PM PST, tomekdm sp7etd via groups.io <tomekdm@...> wrote:

good to hear, radio will be fixed. 73

C30 removed. The end closest to the display came off when desoldering. PCB looks OK. With C30 removed, voltages on Q30 are: E = 1.74, B= 2.41, C=7.76 Pretty much as you mentioned. C30 will be