For frequencies below 30 MHz, S9 is defined as a voltage of 50 μV over 50 Ω at the receiver antenna connector; for frequencies above 30 MHz, S9 is defined as a voltage of 5 μV over 50 Ω at the receiver antenna connector. This refers to an unmodulated carrier signal (N0N) that uses almost no bandwidth; in case of real signals using a given bandwidth, this definition may not be enough since a smaller receiver bandwidth allows a weaker minimum detectable signal, but S-points are still a good tool for comparing received signals.
Continue reading S-meter and signal strengthCategory: Manuals
Manuals for ham radio equipment
Icom IC7100 Panadapter (2nd receiver) – rf tap
Автор не несе жодної відповідальності за повторення. Якщо ви не маєте навиків модифікації такої апаратури, краще не повторювати.
(The author does not bear any responsibility for repetition. If you do not have the skills to modify such equipment, it is better not to repeat.)
Додавання другого приймача полягає в підʼєднанні sdr приймача в точку переходу RF між PA та MAIN платами.
Сигнал в цій точці -30dBm (~S9+40) що на приймання що на передавання. Це трохи забагато для SDR приймача, тому треба ставити атенюатор 10дб.
(Adding a second receiver involves connecting an SDR receiver to the RF transition point between the PA and MAIN boards. The signal at this point is -30dBm (~S9+40) both for reception and transmission. This is a bit too much for an SDR receiver, so you need to put a 10dB attenuator.)
Наша потрібна точка це J3001. З двох сторін по схемі ця точка має блокування по напрузі конденсаторами.
The point we need is J3001. On both sides of the circuit, this point has voltage blocking by capacitors.Continue reading Icom IC7100 Panadapter (2nd receiver) – rf tap
