13-03-2018, 08:03 PM
Hi.
I did get some time this afternoon and pulled it all out of the Tin box. I have refitted the original trimmer so I can do a couple of videos. What I will need to do though is to feed the output into an amp as even using an output transformer and speaker it isn't really loud enough for the camera mic to respond. I can hear the speaker audio in a silent room but ears are better than a phone!!!
The little inverter tends to cause a bit of whistling on the audio so I'll be trying to filter it better, the inverter runs between 7-10Khz dependent on load. Battery current for both HT & LT is around 120ma from two NI-MH AA cells, a bit more than I was expecting. Also remember this circuit is demodulating by slope detection.
I did get some time this afternoon and pulled it all out of the Tin box. I have refitted the original trimmer so I can do a couple of videos. What I will need to do though is to feed the output into an amp as even using an output transformer and speaker it isn't really loud enough for the camera mic to respond. I can hear the speaker audio in a silent room but ears are better than a phone!!!
The little inverter tends to cause a bit of whistling on the audio so I'll be trying to filter it better, the inverter runs between 7-10Khz dependent on load. Battery current for both HT & LT is around 120ma from two NI-MH AA cells, a bit more than I was expecting. Also remember this circuit is demodulating by slope detection.
