VN66AF 27MHz CB amplifier
The 10 meters 27MHz CW radio amplifier is equiped with VN66AF transistor produced by Siliconix wich has some advantages: its cheap, great dielectric insulation and high gain. Here we use VN66AF as an rf amplifier for 10m band (26 … 30 MHz ).
With this 27MHz rf amplifier, small transmitters ~ 200mW, can be transformed in 2 to 3 W 10m transmitters. The band-pass filter attenuates at least 55dB.
For linear applications (AM and BLU) the VMOS FET gate current has to be 20mA adjusted with P1. If we want to use this 10m rf amplifier for FM and CW adjust P1 so there is no current to FET gate. In our case the repose current ( steady current ) is 200mA to 300mA.
VN66AF amplifier circuit components
L1 = 12 turns / 0.6mm / 9mm
L2 = L4 = 5 turns / 1mm / 9mm
L3 = 8 turns / 1mm / 9mm
VN66AF 10 meter CW amplifier circuit schematic
VN66AF pcb layout
about 1 year ago
VN66af for Q1 cant be had anymore. I built this with a mosfet irf710 that I had laying around. Get nothing for gain, that is, unless I do away with the input coupling capacitor, which is C1. Then I get a real good noisy handheld CB and a little output. It just does not work.
I found another schematic based on this circuit. The Datasheet for the VN66AF shows a test circuit that looks a little like the schematic here accept it has more components. Looks more stable.
Does anyone know of a real, working cross to the Q1? I assume it is a mosfet, but I am not sure what mosfet would work. No cross.
about 1 year ago
Uh, anyone know about the vn66 ? What does it cross too. Nothing? So this circuit is a fleatingwangdownersleak…
about 1 year ago
Some wanker on ebay has one for 36 bucks… crazy wanker
about 1 year ago
Hey, Id say forget about this circuit, there is a another one out there you can build with the mosfet irf840. Author claims good watts very comparable to this circuit. Forget the chumps who sell old obsolete parts for 40 bucks for one, pathetic little mosfet.
By the way, its a vmos. Supposedly better in some cases, research it on wiki. Very interesting.
about 1 year ago
If you know the link with that circuit, please write it here so everyone can take a look at it.
about 1 year ago
Electrolover, Sorry for the rudeness. I built this and tried it with irf840, irf 710 and irf740. I’m not really sure how to get it going with those fets. When I couple one of the coils and the gate I get some strong radio signals but only when a 3 foot wire is attached to out put while under 50 ohm losd. With out that there is nothing.
I will try to post the other, but if you google irf840 linear, you will get it number one.