This probably isn’t an “I learned a thing” post, but more of a “I did a thing, check it out” post.
The latest crop of SDR transceivers have intrigued me. A little over 20 years ago, I built a TenTec 30m CW radio. Never got it to fully cooperate, because I think one of the coils was wound wrong. I always hated winding coils. About 10 years ago, the SoftRock series of SDR interfaces by KB9YIG came out (still available here). These were cool because they used your sound card as the ADC. Many before me had figured out that the (80m?) softrock could be modified to operate at 455 kHz, and then connected to the IF output of many radios. I got some help from a filter specialist at work to modify mine, and it worked great. I have a post about one of these investigations.
More recently, I thought the idea of a small, portable, HF rig was cool – especially for vacations or even outings with the boy scouts. The 706 and a car battery is a pain in the neck…. I could do so much more with a smaller setup. I had my eye on the uBitX because they looked adaptable, portable, and modifiable. The radio itself wasn’t terribly expensive, but then there were displays, software (free) cases, tuners, interfaces, modifications…. a whole lot of “other” stuff i would have to acquire. I was still up for it…
And then the Xiegu x6100 came out. It looked a lot like a *cough* Icom 705 – and truth be told, I was seriously looking at the 705, except for one problem. The 705 cost twice as much, and the only advantage, as I saw it, was a touch screen and D-star on UHF and VHF. Neither of those was worth over $500 to me. So I started shopping for deals on a 6100. As luck would have it, I picked one up for $550 at the local hamfest with minimal use.
The next challenge was how to carry the radio and accessories when I went anywhere. I happened ot have a small pelican case from something I had taken apart, and it would fit the radio, but just barely. A bit too tight for my tastes, and would not fit everything I needed to operate for any length of time.
A trip to Harbor Freight for a new tow strap also yielded an Apache 2800 series case.
I picked the orange one just so it stands out form some of my other transit cases. I started with the pick and pluck foam and quickly realized that, well, it sucks. It started coming apart where i didn’t want it to, and i didn’t want to cover it with glue. I was fortunate to score some expanded PVC foam sheets from a friend. I found that 3 layers of the ePVC foam were just a bit taller than the original 2 layers of PnP foam.
I stated toying with the idea of how i could get everything I wanted in the case. I knew the basics of what I wanted:
- USB Cable(s) (note, added a USB-C hub, as well)
- DC Power Cables
- Antenna (EFHW on a PCB based un-un)
- AC charging wall wart
- RF Adaptors
- small dummy load
- (space for expansion)
With 3 layers of foam, I came up with the idea of having several “pallets” within the case, with a rigid base on each, where I could have the foam form-cut for each of the things I wanted in the case. After a little more tinkering, I decided that cordoning off one part of the case as storage for the radio would be best, and then the pallets could stack next to it.
So far, I’ve been impressed with what I can get in this case – I’m planning on taking it on business travel with me, if i have any longer trips (2 days isn’t enough to be worthwhile, but 2 weeks might be).
For the time being, I settled on an EFHW antenna because it seemed the simplest to set up in a park or campsite. I bought a PCB with un-un installed on it, and 75 feet of wire with a kevlar strand in it for strength. I then put a ring terminal on either end, and then measured from one end, and put ring terminals at each of the recommended lenghts for the 10, 12, 15, 17, 20, 30, and 40m amateur bands. While 75 feet isn’t enough for 80m at resonance, it might do OK with the internal tuner on the radio. I suspect 20m will be the band I use the most, anyway. The idea I had was that I can simply unspool as much wire as i need for the band I want to operate, and just connect the right ring terminal to the screw on the PCB. The “80m” (75′ of wire) ring terminal is connected to the screw by default, so, in theory, that section of wire is more or less shorted out, and shouldn’t have a huge impact on antenna performance.
As of now, I also have some coax stashed in the box, and I’ll probably pack an extra wire, and longer coax cables when I do finally use this thing, just in case…. and at that point, I’ll probably have more to add to this post!