A quick comment before people draw conclusions from a single datapoint. The Si5351 can often be configured in multiple ways to produce a single given frequency. That is, you can have arbitrary multipl

Hi Andy, that's a good find, but do you know what power range the YAEGE FC-1 can measure (or safely handle)? I cannot seem to find a spec.

50W into 50 ohms is indeed 50V rms, but that would give you 141 V peak-to-peak. Just mind that the peak-to-peak voltage (Vpp) is not the same as peak voltage (aka amplitude or maximum swing from zero)

Poorly maintained sites with downtimes are also things of the past. Then again, anyone is welcome to create a new site, publish their API and incentivise people to come over to the new site. One does

Hi Hans, just a suggestion - if you'd release the files as archives (.zip), it would save all the trouble with renaming files and automatic extensions, plus the trouble with HTML MIME types and browse

#qcx

Just checked with a scope. The buttons are very noisy, it's not the resistance or pickup. They just generate a very quick and random train of pulses for about 1ms which coupled with the ADC capacitanc

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And my buttons measure 0.5-1 ohm. I cannot possibly see how 1 ohm in series with 3.3k (R45) or 1k (R44) forming a voltage divider with 10k would make a difference. 5V * (3.3k / 10k) = 1.65V on the ADC

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Hans, I could agree on shielding when the QCX is transmitting. However, it's not really the case here, as I never get bogus button clicks even when sending. It's just that when I press the right butto

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I can chime in that I observe a similar problem. I have soldered external buttons on ~5cm wires in parallel to the original left and right buttons, and one of the external buttons sometimes registers

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I know the feeling when the solution seems just around the corner, but let me not take away your time from QSX :)

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Hi Hans, I have an idea for the SIDETONE PWM signal, but it depends on how tight your timing/memory requirements are in your QCX code. You'd probably have to squeeze a high-frequency interrupt routine

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Hi Hans, While it is certainly thoughtful to have such protection especially in a kit scenario, actually I believe the AVR would be protected by its internal body diodes given that R53 is large enough

Regarding the C6 cap, I still think it should have significantly larger value than 0.1uF, since it is in essence in series with the C43-C46 caps, which are larger by capacitance. It just feels that wa

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Wow, brilliant! While I was aware that the woodpecker is not really a very important issue, since it gets drowned by noise and not all use S-meter or decoder, it still nagged me that there has to be a

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Sorry, AUDIO2, not AUDIO1.

May I suggest also that R49/R50 and C39 might be unnecessary for AUDIO1, since you have 2.5V DC bias at the output of IC6/IC7 anyway and the ADC will be happy. Since you already have the C39 cap on th

I realised I should have mentioned I was using Semi QSK. So that excludes Q7 and related circuitry.

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I went through your troubleshooting advice and I agree that there are multiple components that could cause the symptoms. I went through all of them. However I think you believe sidetone is injected vi

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Thanks Allison. I'm sorry I put two issues in one post, they are totally unrelated. The clicks refer to sidetone while TX/practice, and the woodpecker is something that you hear during RX. First, the

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Some measurements: before mod the woodpecker with antenna disconnected would generate 300 mVpp clicks at the audio output (unloaded, full volume). After that it went down to 100 mVpp. Not perfect, it'

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