Thursday, January 04, 2018

New Radio(s) - Pt. 2

As mentioned in a previous post I also got hold of the new SDRPlay RSP1A just before Christmas, so two novel SDRs with rather different architecture were purchased the last month. Below are the two together, the HF+ to the right. The RSP1A, no monster size itself, brings perspective to the credit card sized HF+. There are no LEDs on the SDRPlay. The HF+ has a tiny orange LED for power, and a blue LED for running.

What I want to do at Smøla island the coming weekend is the following:
- Test the SDRs against the Perseus as a reference SDR in a period with the highest signal levels.
- Test the SDRs against the Perseus in a period with the lowest signal levels.

Hopefully, I will be able to note any differences with regards to overloading, and the ability to separate weak signals next to very strong ones. I should also be able to note how they resolve very weak signals. The SDRs will be connected to an efficient beverage antenna, and being a MW DX-er, I will focus on MW and possibly a bit on SW. I won't tune above 30 MHz! Promise!


Chuck said...

I'll be looking forward to this. It seems like an excellent receiverand I expect it to equal the Perseus overall.

Too bad there was so little appreciation of MW DXing by the developer. I cant get very interested in a radio that can only record half the MW band. I'm convinced he could stil have an excellent product if it had allowed full MW recordings.


Bjarne Mjelde said...

Very good point, Chuck. I do hope that a future firmware update might resolve this. The lack of MW coverage has been communicated by several DX-ers. It has the potential of becoming the must-have SDR for MW DX-ers if so happens.

4nradio said...

I agree with the desire for a full MW coverage. Perhaps we would gain bandwidth at the expense of some RF overload spec. That may be fine as most of us do our serious DXing in a low RF, DXpedition setting anyway.

However, the HF+ is so thrifty on USB power and CPU resources it's only a moderate hassle to run two HF+ boxes and two instances of HDSDR (or both receivers in a single instance of Studio 1 or SDR-Console). Bjarne, has Jaguar evolved to permit multiple Perseii for DXing?

I hope you can include your typical sensitivity measurements, Bjarne. The radio seems very low noise but hopefully not at the expense of weak signal demod.

The developer seems to think his SDR# is the end-all program for EVERY form of DXing. I think it's kind of like SpectraVue--more like "lab instrument" software than a DXer's tool, especially for MW DXing.

Bjarne Mjelde said...

Guy, I think two SDRs to cover the MW band would be a hassle. Maybe no so much for a short DX stunt, but definitely in a setup with continous surveillance over the DX season, not least if more than one antenna is in use at the same time. I have five independent setups now, so instead of five Perseus I would need 10 HF+. You also lose one USB port which could be used for a hard drive.
But the evolution will continue!

MO said...

Hi Bjarne,

It would be great if you could include a visit to the NDB frequencies. And if you could make a recording of the NDB segment available I'd gladly check it out :-)

vy 73 + gd DX,


Chuck said...


The price for full MW coverage wouldn't change strong signal handling but rather would increase the noise floor a bit. Result = slightly worse sensitivity.

Since the HF+ has very good sensitivity already, it doesn't matter that sensitivity would be slightly worse for MW.

Youssef doesn't seem to catch that6 point.

I like Bjarne don't want to have 2 receivers for MW. What a pain to find parallels and keep track of files!