Figure 1: CW oscillator level control on the Alda 103 (see text).
I had been operating the Alda 103 CW/SSB triband ham radio, a gem from the seventies, for a couple weeks on the SSB end of forty meters. I received nothing but good reports, such as “very clear and clean” – and “an easy to listen to signal” since I resolved an issue with the microphone input impedance, which on the Alda is slighty different than *any* other amateur transceiver. This was done by putting a Triad audio impedance transformer between the Alda and the Shure 414A Hi-Z microphone…