You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Reply to thread

Message

You could fit another relay in there just like the stock ones. Mounted on it's side with double sided tape. The keying transistor will probably handle the current of having a second relay coil in parallel with it. The more professional way to switch a positive voltage source is to use your friend the PNP transistor. Connect the emitter to the +12 volts from the power switch. Connect the collector to the side of the 100 ohm resistor you want to switch the 12 volts into.

The base lead should be connected through a resistor approximately 1000 ohms (or more) 1/4 watt. The other side of this resistor goes to the side of the keying relay coil that goes from 12 volts unkeyed to 0.6 volts when the amp is keyed. As long as the voltage between the base and the emitter remain close to the same positive potential, the connection between the emitter and collector appear as an open. Once the base is brought to a potential that is lower then the emitter by .6 volts or more, the transistor turns on and looks like a short between the collector and emitter.

PS: It's late and I hope I explained that right.

<blockquote data-quote="Shockwave" data-source="post: 265155" data-attributes="member: 10882">You could fit another relay in there just like the stock ones. Mounted on it&#039;s side with double sided tape. The keying transistor will probably handle the current of having a second relay coil in parallel with it. The more professional way to switch a positive voltage source is to use your friend the PNP transistor. Connect the emitter to the +12 volts from the power switch. Connect the collector to the side of the 100 ohm resistor you want to switch the 12 volts into. The base lead should be connected through a resistor approximately 1000 ohms (or more) 1/4 watt. The other side of this resistor goes to the side of the keying relay coil that goes from 12 volts unkeyed to 0.6 volts when the amp is keyed. As long as the voltage between the base and the emitter remain close to the same positive potential, the connection between the emitter and collector appear as an open. Once the base is brought to a potential that is lower then the emitter by .6 volts or more, the transistor turns on and looks like a short between the collector and emitter.PS: It&#039;s late and I hope I explained that right.</blockquote>

[QUOTE="Shockwave, post: 265155, member: 10882"] You could fit another relay in there just like the stock ones. Mounted on it's side with double sided tape. The keying transistor will probably handle the current of having a second relay coil in parallel with it. The more professional way to switch a positive voltage source is to use your friend the PNP transistor. Connect the emitter to the +12 volts from the power switch. Connect the collector to the side of the 100 ohm resistor you want to switch the 12 volts into. The base lead should be connected through a resistor approximately 1000 ohms (or more) 1/4 watt. The other side of this resistor goes to the side of the keying relay coil that goes from 12 volts unkeyed to 0.6 volts when the amp is keyed. As long as the voltage between the base and the emitter remain close to the same positive potential, the connection between the emitter and collector appear as an open. Once the base is brought to a potential that is lower then the emitter by .6 volts or more, the transistor turns on and looks like a short between the collector and emitter. PS: It's late and I hope I explained that right. [/QUOTE]

Top Bottom