need help

[radio nut]

oh okay. That makes sense now. I figured power up equals powered up the same either way. I guess I will need to go to Fair Radio and get one. My next project is a transformerless ac/dc Meck radio so I will need an isolation transformer quick.

[radio nut]

one last question. in the same room plugged into the same outlet is a zenith 10s ? that I repaired years ago. If my friend turns on his 6 or 8 foot fluorescent shop light the zenith sounds like the lytics are really bad. only picks up local and still hums very badly and very loudly. turn the light off and it is fine. The 1928 stromberg picks up more stations when the light is off but is not really affected otherwise. Any ideas?

[DavGoodlin]

Originally Posted by radio nut

If my friend turns on his 6 or 8 foot fluorescent shop light the zenith sounds like the lytics are really bad. only picks up local and still hums very badly and very loudly. turn the light off and it is fine.

Sometimes the lamp radiates the harmonics that hum, buzz and/or hiss (like a weak signal) on AM and FM. A line filter cannot always fix that, only a well-grounded light fixture may help AND physical separation.

I repaired a friend's Philco 37-650 by adding a line filter I salvaged from a monitor. It had an M-filter, that is a cap across the line, two inductors with common core (like in an old Zenith TV) and a cap on the radio side across the line. It really cut down on interference from dimmer switches (buzz).

Ironically, old T12 lamps and magnetic ballasts seem to generate very little interference compared to electronic ballasts driving linear OR compact fluorescent lamps. The higher the wattage or number of lamps driven, the worse it gets.