gil@limbic.UUCP (Gil Kloepfer Jr.) (08/23/88)
In article <15911@apple.Apple.COM> lemke@apple.com.UUCP (Steve Lemke) writes: |>In article <2253@uhccux.uhcc.hawaii.edu> taro@uhccux.uhcc.hawaii.edu (Taro Nobusawa) writes: |>>...If I unplug the amp input from |>>the D-10 headphon, I don't get any noise and also obviously no music. If I |>>run the D-10 off its own battery, I get no noise and good music. The noise is |>If anyone's come up with a solution to |>this problem (which doesn't seem to be brand-dependant!), I'd love to hear |>about it!! Okay, here's my idea. Please keep in mind that I'm a mere computer programmer by day, digital electronics person by night. I have an idea on what can be done to fix the problem. If you can dig up a set of 2 audio transformers (two of the same), try connecting the primary of each transformer between ground and the audio output on the CD player side, and connecting the secondaries between the auto ground and the audio input to the car stereo. The transformers will isolate the two grounds. I have NO idea what kind of impedience the primary/secondary should be, but I think a 1:1 ratio (ie. isolation transformer) is what is needed. I looked at my Sony D-5 player, and if you look at the power connector, you will see that (at least in mine) the "+" side is the outer conductor, which is generally connected to the device's chassis and audio ground. Why Sony made a positive ground unit is beyond me, but it seems like they did. I would appreciate knowledgable people elaborating on this idea... +------------------------------------+----------------------------------------+ | Gil Kloepfer, Jr. | Net-Address: | | ICUS Software Systems | {boulder,talcott}!icus!limbic!gil | | P.O. Box 1 | Voice-net: (516) 968-6860 | | Islip Terrace, New York 11752 | Othernet: gil@limbic.UUCP | +------------------------------------+----------------------------------------+
dave@onfcanim.UUCP (Dave Martindale) (08/26/88)
In article <183@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: > >I looked at my Sony D-5 player, and if you look at the power connector, you >will see that (at least in mine) the "+" side is the outer conductor, which is >generally connected to the device's chassis and audio ground. Why Sony made >a positive ground unit is beyond me, but it seems like they did. The D-5 is negative ground. It just connects the center pin of the power conductor to ground, rather than the outer contact as you assumed.