7159kc trx qsk

I had a rough time understanding and choosing a proper qsk for my TX and receivers. If you see my early post you will see that I used different modules to make Transmitter and Receiver

In this transceiver i tried to implement TX and RX chain in a single BOX. My results are very satisfactory. So, lets hear the success story of QSK.

By the way For this TRX Next step is to make a cw band xtal VXO of 7000kc (This xtals were given by my friend Arya ) , and 7159kc DSB TX.  Need of VXO is apparent. A single stage af filter is also good. But let me first put it on air with just 10 foot high about 50 feet long wire. It works. Years of homebrewing has told me to make a solid brew. Put your modules firmly , in  a box, shield them. use decoupling , use plenty of space. Make modules and make it in small steps. Test it and see that it works.

Filter 40 meter

Qsk

Filter

Yes wheel is reinvented and revised.
I have put the few fotographs here and will write more about it.

1. You need a Relay DPDT (8 pin relay) , a must to change over the Antenna and Generate control Vcc  ie. RxV, TxV.

2. Transistors can be used to switch few modules. (will describe later on). For SSB single relay will work but for CW you need more control mechanism. Or use a relay and manually switch TX RX on off, clumsy.

3. You also need Diode 1N4148 switching for protecting the front end of RF Amplifiers. I implimented the M0DGQ as given in the SPRAT magazine. picture given below. Here if there is no control voltage switch protects our front end. This switching always introduces some signal loss . but ok with good dipole external antennas.

4. You should use "10k+LED" for indication of Vcc, On-Off,TX,RX, etc. This indication helps in quick visual  fault finding or working of the stage. It helps a lot during the development stage. If current consumption is an issue then later on remove it.

5.I will be listing all the switches usage. Relay, Diode, NE555, 1N4148, BC548,1N4007.

QSK

TRansceiver

VK3YE 

It has RF amp, Ground switch 

and Control voltage

Another QSK

VK#YE VXO