Probably a stupid question, but...

Yes, it's called a transistor and depending on how accurrate you need the transfer and how stable it should be, depends on additional design to the over all circuit.

A basic NPN common emitter could be used as a current sink type of output where you know the supply voltage on the load side and simply calculate the needed current which would translate to voltage across the load on the circuit.. It's all about gain ratios.

You can add a diode in the base circuit to help with tempo problems as the transistor is subjected to various levels of heat,which will alter the gain setting..

Jamie

There's no single component that I'm aware of that will do what you've asked for. If you will elaborate a bit on what you're trying to accomplish, someone will surely be able to assist in a solution. Likely, a circuit will have to be designed to do it, but without more info, it's just a shot in the dark. Vague questions will get vague answers.

Thanks for the reply. Wasn't trying to be deliberately vague, just didn't know what to specifiy without diving into the whole thing. And didn't want to look like I was trying to get someone else to do my homework. What I am trying to do is bias a JFET for optimum performance while keeping it very near the pinch-off voltage. In this case I am using a 2N5486 (NTE451) to feed signal to a BJT (SK3245 - NTE199). Problem is, it works fine while the batteries are very fresh, but when they start to lag Vgs becomes greater than pinch-off. Please see my post to Jamie for more details. And thanks agian.

Dave

Man, I knew that I was going to end up using a transistor to do that job, I just didn't know how. So anyway, as I mentioned in my post to Dave M. I am trying to use a JFET (2N5486 - NTE451) to feed signal to a BJT (SK3245 - NTE199) while keeping Vgs very near Pinch-Off. Problem is, as the 12V worth of batteries begins to wane, Vs remains the same while Vg falls, resulting in Vgs surpassing Pinch-Off. Please see my schematic posted to abse for particulars. And please understand that I know next to nothing about RF, I am learning this as I go along. That much will become obvious very shortly, if it hasn't already. :)

Thanks for the informative post.

Dave