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QCX 40 No Sidetone and output is raspy

Alan G4ZFQ
 

Did you change the tone from the default setting?  If so change back to the default tone it should clear up the issue. There is a discussion here about that.  If I recall it was just after 1.3 was released.
This is earlier, https://groups.io/g/QRPLabs/message/39812?p=,,,20,0,0,0::Created,,default+sidetone+frequency,20,2,0,44099475 but it seems you've got a good memory!
Further searches might reveal if there was any update, or a look at the firmware changelog.

73 Alan G4ZFQ

N3MNT
 

Did you change the tone from the default setting?  If so change back to the default tone it should clear up the issue. There is a discussion here about that.  If I recall it was just after 1.3 was released.

 

Very possible. Nothing is where it would normally be because I'm testing. There's a rats nest of power and RF cables. The QCX is working as it should. I'll test the whole setup this evening but clean it up first. 
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73
NE5U

Mike

Gregg Myers
 

Hello Mike,

Is is possible you are picking up some RF interference from the higher power output of the Amp? I had a similar bad sounding sidetone and then made sure I cleaned up my rats nest of RF cables and put the DC power cables through a couple of EMI toroids. That cleaned my sidetone right up.

73,
Gregg 
w7grm

On Thu, Apr 2, 2020 at 9:17 PM Michael Lloyd <mikell@...> wrote:
:-/ Well, I put the QCX signal into a 50 ohm pass thru terminator then to the scope and the sine wave is gorgeous. 7.020 Mhz, which is exactly the frequency I set. About 2.5W out. No problems at all. I'll hook the amp up tomorrow and take a look at it's sine wave. I don't know what the lack of sidetone is about but I'll keep digging. I'll try another headset too...
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73
NE5U

Mike

 

:-/ Well, I put the QCX signal into a 50 ohm pass thru terminator then to the scope and the sine wave is gorgeous. 7.020 Mhz, which is exactly the frequency I set. About 2.5W out. No problems at all. I'll hook the amp up tomorrow and take a look at it's sine wave. I don't know what the lack of sidetone is about but I'll keep digging. I'll try another headset too...
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73
NE5U

Mike

 

I finally installed a jack in my QCX so I can could the 50W amp and test it all as a package. All of that worked. Just for grins I turned my FT-891 on to see what the QCX sounded like (transmitting into a dummy load). I was.. how should I say this, horrified at what I heard. I plugged in my headphones and also discovered that there is no sidetone. Just a thump sound. I'm about to take a look at the schematic but I thought I would see if anyone had any ideas.

I think that the QCX was working before I wired in the switching wire for the amplifier. It's been a few months since I finished the kit. I am not sure I didn't screw up one of the IC's. We'll see.
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73
NE5U

Mike