Bias design, amplifier design, filtering etc.

[bob85]

yes the pi filter is intended to help isolate the bias circuit from the rf,
i will try an extra resistor to load the pass transistor the next time im playing with that type circuit,
right now im building a bench in the spare room so that i can get back to playing radio

 

[ken white]

yes the pi filter is intended to help isolate the bias circuit from the rf,
i will try an extra resistor to load the pass transistor the next time im playing with that type circuit,
right now im building a bench in the spare room so that i can get back to playing radio

LOL... and have fun!

 

[-=PEAKABOO=-]

So post up...

I was referring to the copycat amp "assemblers" that have hit the CB scene, not you ken

 

[BOOTY MONSTER]

people are still trying to copy what you did peakaboo .

http://www.worldwidedx.com/general-cb-services-discussion/35497-t-s-350-users-2.html

 

[bob85]

they do say that imitation is the sincerest form of flattery

 

[-=PEAKABOO=-]

they do say that imitation is the sincerest form of flattery

That is true Bob.

I love to help people out but it seams that most of them have ulterior motives. I know that RF amplifiers can be a big pain in the ass but if folks are just wanting to copy so they can make a buck I got nothing for them.

 

[ken white]

That is true Bob.

I love to help people out but it seams that most of them have ulterior motives. I know that RF amplifiers can be a big pain in the ass but if folks are just wanting to copy so they can make a buck I got nothing for them.

Well said...

 

[mackmobile43]

That is true Bob.

I love to help people out but it seams that most of them have ulterior motives. I know that RF amplifiers can be a big pain in the ass but if folks are just wanting to copy so they can make a buck I got nothing for them.

There are a couple out there still re-inventing the wheel.

dwb biased1x4-0.jpg

 

[-=PEAKABOO=-]

There are a couple out there still re-inventing the wheel.

dwb biased1x4-0.jpg

reinventing the wheel?
looks like a davemade 5 pill, are you talking about the bias circuit that has been added to it?

 

[mackmobile43]

reinventing the wheel?
looks like a davemade 5 pill, are you talking about the bias circuit that has been added to it?

YES

 

[-=PEAKABOO=-]

Is it using the 3 transistors mounted to the heatsink for thermal control?

 

[mackmobile43]

Is it using the 3 transistors mounted to the heatsink for thermal control?

That board has 3 bias circuits, one for the input stage and one for each output stage.

Those are the voltage regulators.

If memory serves the tracking is below the board near the finals, he gouged tracks in the heat sink to route the wiring for that.

 

[-=PEAKABOO=-]

That board has 3 bias circuits, one for the input stage and one for each output stage.

Those are the voltage regulators.

If memory serves the tracking is below the board near the finals, he gouged tracks in the heat sink to route the wiring for that.

10-4

 

[Crusher]

Good topic, I use a regulator (8V@3Amps)with a pass trasistor and 2 flat style diodes using a TO-220ac style case. Works decent and seems to do very well. Have Bob to thank for getting me interested in a biased amp some years back. Similar to motorola design with a few changes. I generally use 1 circuit per 2 transistors. I could use it for a 4 pill amp, but don't.

 

[NorthStar]

Good Stuff guys. Let's keep it rolling!