Hold the phone. The 220 K resistor R2 was not making a clean connection to the plus supply..693v so pretty much.7
this particular band suffers in the winter months due to atmospheric conditions at this frequency. I know I am transmitting because I can see my call sign being spotted on the website and I am receiving stations but I have yet to make an actual contact.
no sooner did I click send on my last post did I make the first of two connections using the interface. Attaching a screenshot of what it looks like on the computer went to ham radio stations exchange location and signal reports. So it works!
well now I have to report unfortunately some thing has happened and I am not getting the right level of audio out of the circuit to drive the transmitter. The attached picture of the scope is what I see coming into the circuit from the laptop, what I see coming out of the transformer, and what is going to the radio. The laptop is sending the maximum level of audio that it can which is what I need to trigger the relay.
Do you have a link to this circuit? I like the 555 it’s an old friendIn ham-speak, the function desired is called "vox", short for Voice Operated Transmit. That sort of circuit has been published in every Radio Amateur's Handbook since the early 1980's and is fairly well designed. It uses a quad opamp, a 555 timer IC, and a single transistor, and will run on 12 volts. The circuit in this thread will also work, but the value of C2 will need to be reduced.
And the power and common connections as shown will be a bit confusing.
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