Re: DSB transceiver for Digital mode
Ron,toggle quoted messageShow quoted text
Thanks for the questions.
1. The PCB size is around 100x64.
2. The heating resistor is recommended for 14MHz. It is really a balance between short term and long term but I see overall improvement. This idea is very rare so I need some more experimentation from you guys.
3. The real concern is not sensitivity but SNR. Since the output impedance is several hundred ohms, by using one transistor, the signal is big enough to give 40-50dB, already bigger than recommend 30dB. My previous version was LM386 and I don’t see much difference. However I have to say that the receiver SNR report is noticeably worse than big radios. I can easily improve receiver itself but considering transceiver overall, I have to sacrifice a bit. The receiver performance is reasonable to match one-watt DSB transmission. You have to balance.
在 2019年5月6日，上午6:24，Ron Stone <rsstone2@...> 写道：