Supply Cable

i have a radio and a dc supply for it.whenever i increase the cable length , fading occurs in radio?

i tried on all adapters, when i increase the cable length of dc supply , fading occurs.i dont what is the reason. i suspect stray capacitance and inductance in the cable affect the radio.if so , is there any circuit to block this stray capacitance and inductance at the end of the terminal.

the fading of the radio varies whenever i go near or far around the dc supply cable.so iam almost sure that it is stray inductance and capacitance plays major role.help me with a simple solution.

i dont think radio has any problem.

a lot of strange answers. How long is the cable?

Make sure you bypass the supply connection in the radio itself. Bypass caps are a requirement in all RF circuitry, but some simple schematics leave it out. A high quality 0.1µF ceramic cap in parallel with a 10µF elecrolytic will do.

With no bypass caps, the wires act as an inductance and capacitance and change the performance of the circuit.

Another possible (but unlikely) problem is voltage drop in the cable. Measure the DC supply voltage in the radio and see if it is significantly less than it is from the adaptor. If so, use heavier wire in the cable.

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