Sunday, November 3, 2013

Raspberry pi wobbulator

Tom Herbison has developed an excellent test equipment using the raspberry pi.

This can be used to  measure crystal frequencies, filter performance etc..

Tom's blog contains all details about this nice project.

Raspberry pi wobbulator needs 2 more plug in boards
    1) AD9850 DDS Module
    2) ADC PI Module
and an envelope detector (seems similar to the one used in the old AM broadcast receivers)
AD9850 module is available in e-bay.
ADC PI is a product of ab electronics.co.uk.

Since raspberry pi has GPIO pins,  it will be easy to interface a graphic lcd. Once the wobbulator program is modified to display the data in lcd, then the  raspberry pi wobbulator become a handheld device.

Nice idea uhhh??

This is time to take raspberry pi out of the shelf.  Or maybe it's a good idea to keep this project for next year. :)

I have tried couple of Linux distributions in raspberry pi.  Used my 32inch Samsung television as the monitor. Raspberry pi needs at least 700mA , 5V power supply.  I used my Samsung galaxy mobile charger to power the pi. This credit card sized computer is a good choice for people who want to try Linux.

Multiband exciter stages....

G6LBQ multiband exciter is almost finished.

Couple of things in the todo list including the LSB/USB crystals and crystal filter unit.
Certainty I have not tested any of the stages other than 1 & 2. I just measured the current consumption of both stages.  23-25 mA deflected in my multimeter.

MK2 exciter uses LM380 as the audio amplifier.LM380 (8 pin) version is not readily available in the market, I need to look for a good source.




Friday, November 1, 2013

Starter Post

Well , This is my first post about experiments in Amateur Radio....

Recently I started building one Transceiver based on the G6LBQ MK2 Exciter.

Couple of weeks back I received the Exciter board from DXKits




Exciter Stage - 1 is just finished :)...


I have built one Band Pass Filter which covers the entire HF Bands..


G4CFY kit(SPECTRUM COMMUNICATIONS) is used to build the BPF.

I will post test results of BPF, and new pictures of exciter stages in coming days..


Vinod