VK4DD Ham Radio

Brisbane, Australia

Friday
Oct 31st
Text size
  • Increase font size
  • Default font size
  • Decrease font size

VK4DD Ham Radio Projects

PA Control PCB

PA Control PCB

This is our PA Controller PCB This module can be used in an Amplifier or a Transverter.

It is an all in one solution, and combines:

  • Sequencer,
  • Solid State Switch,
  • VSWR protection,
  • VSWR indication and monitoring
  • Power measurement
  • Voltage measurement
  • Current measurement
  • Temperature measurement
  • Provides Serial Data output for our GLCD display.
  • This is a fitted on one single PCB (we note that an ext Coupler required for VSWR/Power signals).

This project is based around a PICAXE 20X2 microcontroller, which can be easily changed to suit your needs

In the forum we have programs which you can download onto the picaxe, which other users have sucesfully modified these to suit their needs.

The Picaxe can be easily programmed with just a serial port and some free software . Click here for the PICAXE Software.

The GLCD which we recommend to use with this project is available here. Click here for more information on the GLCD.

Click here for the VK4DD webstore.

 

More information is available on our forum: Click here to go to the VK4DD Forum.

 

 

48V BLF278 PA PCB

48V BLF278 PA PCB

This is a low cost solution to make power on 2m. It is based on the BLF278. The initial design came from Nanko PA0V.

Nanko has used 5 to make a big 1.2kW solid state PA.

Read more...

BLF248 MARK II PA PCB

BLF248 MARK II PA PCB




This is the MK II (second generation) BLF248 144 Mhz amplifier PCB.


I developed the first version (MK I green PCB) in July 2008 for Amateur service operation in the 144 to 148 Mhz band. Since than many amplifiers have been built and tested by Hams all over the world. The basis for this amplifier is an 28V FET which is used a lot in TV transmitters because of its linearity, ruggedness and high efficiency of 68%.

The BLF248 is a high end FET with one of the highest efficiencies and a Max VSWR of 50:1. (see Philips/NXP data sheet). As such it exceeds the specs of the commercial available solid state amplifiers for amateur service.

Read more...

VK4DD BLF248 PA - NEW MKII SINGLE BOARD PCB

VK4DD BLF248 PA - NEW MKII SINGLE BOARD PCB

Note

This PCB is back in the web shop. I made a new version with the same output circuit as the DUAL BLF248 MKII.

It has now got better efficiency and more output power than ever.

If you were after the same power level but on 48V, than see the 48V BLF278 PCB.


The BLF248 144-148 MHz amplifier PCB (300-350W out)

This project started in July 2008 when I developed the MK I version for operation in the 144 to 148 Mhz band. Since than many amplifiers have been built and tested by Hams all over the world. The basis for this amplifier is an 28V FET which is used a lot in TV transmitters because of its quality.

The BLF248 is a high end FET with one of the highest efficiencies and a Max VSWR of 50:1. (see Philips/NXP data sheet). As such it exceeds the specs of the commercial available solid state amplifiers for amateur service.

But now the Single BLF248 MKII has been improved, and is better than ever. The MKII PCB is capable of producing up to 400W PEP.

But I recommend to keep output between 300 and 350W. If you want more power than look at the MKII as well.

 

Read more...

HF/50 MHz Solid State PA PCB

HF/50 MHz Solid State PA PCB

The HF / 50 MHz 2x BLF177 SOLID STATE Amplifier

This amplifier is based on 2 x BLF177, a very rugged Fet which has become, in a very short time, one of our most popular products. The fets are rated 150W each, but Harris, a commercial amplifier producer uses 2 of them to make 500W!

The PCB is a high quality 1.6mm board made from the very best FR4 material. Excellent industrial quality boards.

This Amplifier development board retails for US$ 25 while stocks last!

Read more...

Amplifier Display

Amplifier Display

This display was developed to be connected to a solid state amplifier. It communicates with our new PA Controller PCB.

Three push buttons (not in kit) Are used to navigate through the Menu. The PA controller (right hand side) is used to collect data and send this to the GLCD display.

Copyright VK4DD.

 

Read more...

GPS Grid Master Display

GPS Grid Master Display

This GPS Grid Master Display does much more than the name suggests.

Beside calculating the grid square and your position inside the grid square it also calculates your antenna bearing for the station you like to work. Ideal for in the shack to work DX or just a great tool when portable or during the Field Day. Quite handy when you don't know where you are or where to point your antenna or dish.

This project is also used to monitor if there is 3D lock for Jupiter and Rockwell GPS (Commonly used for 10Mhz references).

Since we first introduced this project many more features have been added...

Read more...