Walford cw tranciever part 2

ABOVE is the build so far.The RX detector stage cannot be tested without the RF filters fitted so the next stage is to wind the toroids for the low pass filter and the band pass filter. The next few stages after this are fitting the components for the transmitter followed by the RX muting components, side tone components and finally the TX output and filter. The kit comes complete with all components needed to wind the toroids and has a detailed chart of windings and capacitors needed for any particular band you are winding for.In my case its 40m. Not all parts supplied are needed in the build as the components needed are band specific.Winding the toroids was straight forward and took only 10 minutes to fit along with the band dependent components. Some components need fitting in series or parralell at there location points depending on the band of choice but this is all very well explained in the build instructions along with winding details and component value, all of which are included for any band up to 20m. So depending on the band you choose to build the rig for all components may not need using. Below is the board with the RX filter fitted. This allowed me to now test the RX detector by fitting a temporary connection between the antenna pad and the RX RF input pads (yellow wire) and connecting an antenna. Worked fine with signals heard but lots of QRM as the CQWW contest was on so there was a lot of ssb stations close by.

The next jobs to be done are to fit the components for the transmitter,RX muting components and then the side tone components along with the output stage with the appropriate tests for each stage. The final stages are to fit the TX low pass filters before testing the output and aligning the RX filter. On testing the RX i did get some broadcast station breakthrough especially at night so i will see how i get on with this. I have thought about fitting another xtal in parralell with the one already fitted to see if i can get any extra band coverage as it does seem to be very limited but was warned about this if i was using my own xtal instead of the supplied resonator but this was for 80m.BELOW is the finished kit and all thats left to do is align the RX filter and try on the air.

On air test

I powered the rig up and all seemed as it should be. I peaked the two capacitors C1 and C2 against a steady signal so was now ready to try the transmitter. I tested power out and got the stated 1.5 watts out to a dummy load using 13.8v supply. Using the 9v battery which i have used through the build gave me around 700mw but the battery is near dead anyway. I did notice one thing i will have to investigate and that is power drop when tuning down the frequency. I am new to the electronics side so no doubt this will be a new learning curve which isn't a bad thing. I hooked a key up and gave a call and a local station came straight back to me. I can't use this as a true test as the station was local but the radio works as it should and the recieve side seems to be ok for what the radio is.There is slight broadcast station breakthrough at night but again this isn't a top end radio and more than anything this was built for fun and the experience of building a kit. In those terms i was pleased and look forward to more projects.

The fancy stuff

The next thing i want to do with this rig is house it in a box big enough to hold the tranciever board and fit the vxo cap and tuning knobs to the case using conventional pots. I thought of housing it in a box big enough to hold the tranciever board along with a vswr indicator circuit and a small T match amu . The tranciever comes in at 10x8cm so a box 10x15 will be plenty enough to house the tranciever,amu and vswr indicator and if im very luck and keep things tight i may even get enough room for a 9v supply just to make it ultra portable just for fun. Keep an eye out in my album section for the finished job.