Irwell Transceiver Update & Red Pitaya SDR

 

It has been just over nine months since I made a post on my blog or provided any updates on the "Irwell HF Multimode Transceiver" project that I have been designing and developing for what feels like an eternity.

In my last blog post, I provided details of the multimode modulator I built for the "Irwell" transceiver. This tested out okay, but I was unable to carry out any on-air testing, as I had yet to design and build the required transmitter amplifier stages needed to get the transceiver on the air. Fast forward nine months later, and I am somewhat embarrassed to admit that I still haven't designed the transmitter amplifier stages!

In my defence I can substantiate and justify what, on the surface, may appear to be a lack of progress or abandonment on my part, so here goes: 

1. I have been busy working on a modular homebrew SDR transceiver project based on the Red Pitaya (AKA Stemlab) FPGA microcontroller board, and I wanted to get this project working, and to the point it also required transmit amplification, the idea being I would design a transmitter amplifier module that  can be used with this project and the "Irwell HF Multimode Transceiver".
   

2.  I found it neccessary to improve my software programming skills in order that I could expand and improve the Irwell VFO software and also produce software for a controller board I designed for the SDR transceiver. This has been a HUGE time sync but worth the investment of time!

So there you have it this is where I am upto, the "Irwell HF Multimode Transceiver" has been updated with some significant software changes and I now have two transceiver projects near to completion with both requiring some transmit RF amplification.

Next I want to start documenting my Red Pitaya homebrew SDR transceiver build and once I have done that I will do a post on the "Irwell" software development changes that I have made, but for now here is a quick screen grab that shows the new software in operation.

The new software contains dedicated band tables, and as you can see from the image above the transceiver has ventured into the Darkside by introducing channelized CB Radio bands. The new software also includes dedicated bandtables for the Shortwave bands, HF air aviation and HF Marine bands, and of course, Amatuer radio. The Bands and CB channels are scrolled through using an additional mechanical rotary encoder.

Thats it for this short blog post, until next time... 

 

 

73's From Andy G6LBQ

Its all about the Radio Ga Ga...

 

 

A Multimode Radio Transceiver Modulator

Following on from the last blog post that I made in July 2024, I present the progress I have made with the microphone preamplifier stages for the Irwell HF Transceivers modulator.

As per usual time has moved on and I have been sidetracked by other projects but with that said, the Irwell HF Transceiver project is and has always been a long-term project.

Since my last update, I have produced and developed various prototype circuits in a bid to get the modulator finished, some of which are illustrated below.

Microphone Pre-Amplifier For The Irwell HF Transceiver

Back in October 2022, I posted details on the blog of a "High Performance AM, CW & SSB Modulator for the G6LBQ Irwell HF Transceiver" this module was somewhat experimental and, for me, a practical introduction to the MC1496 modulator IC. The module contained no microphone amplifier stages, as it was my intention to add these as a separate module at a later date.

  To view my 2022 Modulator blog post article, click here.

In this blog post, I get to grips with the microphone preamplifier and share some of my design methods and thought processes along the way.  Note it is not my intention to provide a step-by-step guide to the design but more of an insight and reference.

The success of this module is crucial in order that I can continue the development of the final transmit stages and achieve finished project status.

A VHF & UHF RF Multicoupler.

Here at the G6LBQ ham shack, I have various receivers and radio scanners that I use for monitoring the VHF/UHF ham bands and other RF signals that interest me. In an ideal world, each receiver would have its own dedicated antenna but that is not practical for me so I have decided to design and build an RF Multicoupler.

The main application of an RF Multicoupler is to enable multiple receivers to share a common antenna and it does this by splitting the incoming signal into a number of output ports, as illustrated in the image below.