Re: LF: OT: Racal vra549c Tuner

[Andy Talbot <andy.g4jnt@gmail.com>]

It is not that specific model, but I do have a small man-pack type Racal auto ATU that has a not totally dissimilar output stage

2C10 is 68pF

2C13 is 180pF

But in mine 2C11 does not exist.

The main inductors and capacitors use the same configuration, except that a bank of inductors has a separate bypass to reduce stray L at high frequencies.

The circuit diagram can be found at http://www.g4jnt.com/DropF/racalatu.gif

I don't know its type number, I only had the PCB and it is now mounted in a diecast box I don't want to dismantle

Andy  G4JNT

On 28 June 2016 at 21:14, Peter <pws@df3lp.de> wrote:

Hi All,

Off topic:
I need some info about the Racal vra549c antenna tuner.
All I have is the schematic:
http://lf-radio.de/misc/sw/Racal_vra549c_schem.png

I'm looking for the values of those 3 capacitors at the
antenna shown on the right: 2C10, 2C11, 2c13. I know
that they are intended to rotate/shift the antenna
impedance into a region where the subsequent circuit
can handle it (guess above ~10 MHz).

???

73 de df3lp,
Peter