zondag 12 oktober 2014

Bitx20 V3 "Dead Bug Style" The S-meter

Last week I added a S-meter to my Bitx20.I used the design which was included in the purchased Bitx20 V3 PCB`s by  Sunil Lakhani.This S-meter,of course,is not a real acurate meter.Actualy it`s more a fun gadget driven by the audio output.But it looks very nice.I used an old S-meter from a Danita 27 MHz CB rig.For the old Kenwood look,I connected a 2Watt 150 ohm resistor in the power supply to the light bulb of the S-meter.Now I have a 4,5 Volts on the light bulb,whitout heating up the resistor.It gives a warm glow on the meter scale.If you take a look on the internet you will find a lot of designs for S-meters.They come in different shapes and sizes.RX/TX,so you can monitor your ALC in TX,and the ones with the AGC support.This AGC is also audio driven.I decided to keep it simple,because I already have heard the AGC on my Multiband Bitx which is very good.
This is the diagram I,ve used on my S-meter.

parts:

1X Potentiometer 100Kohm.
1X Potentiometer 470Kohm.
1X resistor 1Mohm 1/4 Watt
1X Capacitor 680Nf.
1X Transistor BC548

While I was testing my S-meter,I heard a round table conversation somewhere at the end of the band.A few German HAM`s on holiday in Spain where having there daily QSO.At the end of this conversation,I called myself in and a EA-station returned my call.We had a nice talk about the wheater and the fact that I used a homebrew transceiver.I made this QSO with 1,5 Watts and the other HAM was QRV on his sailboat with 400Watts.So,as you can see,It only takes a few parts and a drive to make a nice QSO whitout spending a lot of money.With this S-meter,I now think this Bitx20 V3 Dead Bug Style project is finished.Next........finish the Multiband Bitx.

woensdag 1 oktober 2014

Multiband Bitx: Sneak Preview of the case.

Picture of my Multiband Bitx project so far.In the front you see the VFO knob and display from the PA0KLT VFO and the push buttons.Just like my earlier builds.I used a VU-meter from an old Hitachi bandrecorder.Frontpanel is copper PCB board painted in white.