AWA 6AQ5 Transmitter (continued)

 

At https://youtu.be/nJgJenvi2x4 I've posted a demonstration video of an entry/novice station as it might have existed in the mid 1950s running on 40 mtrs. It uses a National NC-57, a receiver that was introduced in 1948. The transmitter is my single 6AQ5 running 6-8 watts out. For more information see the video description.

AWA 6AQ5 Transmitter (continued)

 I've gotten the power supply built into my 6AQ5 transmitter. I used an old school PS design: a 6X4 full wave rectifier with a capacitor input filter feeding a 20K bleeder resistor. 

This transmitter is working and sounding fine. Power out maxes out around 6 watts with 15 watts input....a couple of items I can look at 1) calibration of my watt meter 2) the value of my pi network coil. Compared to 8 to 9 watts out 6 is not a big deal. I'll poke around at this issue later 

For now I'm pairing this transmitter with my hopped up National NC57. See https://w0vlz.blogspot.com/search/label/NC-57  .

**** Addendum **** 

Tonight I worked Don , N0DLR, using my NC57/6AQ5 station.  Even with a lot of static we had a successful QSO. The Reverse Beacon Network reported many hits in the North East US with a few more scattered to the south and west of me. My new rig is in the log.

 

AWA 6AQ5 Transmitter

I've gotten the RF portion of my AWA 6AQ5 transmitter ( https://www.antiquewireless.org/homepage/pcb-item-12 ) done and tested on 80, 40 and 30 mtrs. This transmitter sounds nice on 80 and 40 running 8-10 watts out with a single 6AQ5. It doesn't sound quite as good with HC49S crystals on 30 but it is still acceptable. 

The plate tuning and load variable caps are under the chassis. Temporarily I'm running with an external 300 VDC power supply. Eventually I'll add a power supply in the spare space at the rear of the chassis. The PS transformer and rectifier will go on top with the fuse, filter caps and filter choke underneath.

 

The PC Board and parts list from AWA allows for a straightforward semi-kit or homebrew project. My thanks to the AWA for making them available.

 

KC7WXD built one also. See https://www.youtube.com/@kc7wxd

 

Does anyone know when PC Boards started showing up in tube rigs? Were there any before the Knightkit R-100? It used a PCB for most of the components. See its review in the Nov 1958 issue of QST.