This is the 20 year old never used Realistic HTX-100 10 meter SSB/CW transceiver I purchased on eBay. It is just like brand new. Not even a scratch on it. I bought this rig (ham speak for transceiver) to be the last intermediate frequency module for use in any portable microwave system I may assemble. I have nothing else yet so this is the start, the basic first building block.
In the world of radio, being able to hear or transmit on a desired frequency, a series of steps called frequency conversions are necessary. This radio has several “conversions” inside to get from 28 MHz down to audio at 200 Hz to 15KHz.. Between this radio and the microwave frequencies (above 900 MHz) will be at least one more converter “box” that will listen at say… 902 MHZ and output a signal at 28 MHz that this radio will “hear” and covert to audio. The reverse process works the same for transmitting.
Changing or adding converters will let this 28MHz radio talk on any other frequency I desire. Each converter will have several conversions within themselves. It’s all a big daisy chain of intermediate frequency (IF) stages.
I could do the same with the radio (the Ten-Tec Omni VIII) that the HTX-100 is setting on in the picture but the Omni is bigger, much more expensive and harder to make portable. I also don’t need the 200 watts to operate the converters.
In the conversion process what makes the radio “good” are the electronic parts that are closest to the antenna. In this case the converters. The 28 MHz radio does not need to be super sensitive (able to hear well). It just has to be relatively stable and reliable.
I have the HTX-100 turned on here in the picture. Being 20 years old, I am conditioning any electrolytic capacitors that may reside inside. I call it a no stress burn in. Even as old as it is, it’s still pretty much state of the art. It is internal computer controlled with Phase Locked Loop frequency control. The box even says “packet ready” which at the time was a new form of digital communication. 25 watts output is standard but there are ways to get over 35 watts. I actually only need about 20 miliwatts! Being so old, there are a lot of “updates” written for this radio, mostly for pirate CB type operation such as out of band coverage and more power or audio mike boost.
I remember when Radio Shack starting selling these radios. I knew the primary use would be from CBers bootlegging on the amateur bands. At the time it kind of pissed me off that Radio Shack and Uniden (the maker) would cater to that illegal activity. But here I am enjoying the very same radio.
There are still illegal radios being made and sold for that same purpose. No real ham will want a built in echo chamber or courtesy “ping” in his amateur radio transceiver. That’s not in this radio. Sorry, I diverged off the subject a bit. I thought those days were long gone…
I didn’t think of this use for the radio by myself. It has been used for this new (microwave) purpose by many hams before me. Actually with the use of converters it has been used for every ham band from 50 MHz (6 meters) and up. Building or buying converters is much easier than starting from scratch on every new frequency a ham wants to try. Converters are the defacto method for almost every amateur system.
This is my first step in a new spectrum to explore. I can hardly wait to do more but I am doing my homework first and studying the basics. I am not in a big a rush. I enjoy the trip more than the destination. That is what life (at least on earth) is about… the trip. Of course I am first going to be poking around inside this new (old) box of electronics!