So, how about the Wideband Port - How's it look modified..?

Okay, since Friday’s BIG news about the RX1_L Port modification, some were probably wondering what the RX1_W Port looks like…Well, I’m here to impart that information to you and show you the results…

First off, the mods I did were to the RX1_L Port (shown in the yellow circle) and RX1_W Port (shown in the red circle). All you need to do is remove the coils from these two spots and you’re DONE. No more mods necessary (for now, later on when there are apps that support two receivers, you can do this to the RX2_l and RX2_W Ports, too). Here’s the reference picture to use for V1.4 Boards:

Once you remove the coils from those two spots, you’ll have GREAT HF receive. Now, the receive for the RX1_L Port has been well documented by me, @nn4f_radio, and others - so I won’t be shooting pics of it, it’s the same as Friday’s pictures for V1.4 hardware. The Wideband Port results follow for bands that are active now in the early afternoon here in Iowa - more to report later for 80/75m later tonight:

Here is the AM Radio Band (tuned to 1450 kHz AM KMRY in Waterloo, Iowa) here in the U.S. with the Wideband Port:

Here is 5.0 MHz WWV on the Wideband Port:

Here is the 40m Band with the Wideband Port:

Here is the 20m Band on the Wideband Port:

Finally, here is the local Weather Radio Station WXL61 In Cedar Rapids, Iowa at 162.475 MHz on the Wideband Port:

EVERYTHING sounded good in the HF Band using this mod. Nothing was distorted and everything demodded perfectly clean on AM, LSB and USB modes. The only anomaly I found was that the 162.475 MHz it was pretty scratchy sounding and I was using the Narrowband FM Mode in 5 and 8 kHz - this may be because of how the software app (SDRConsole V4.0) demods FM using this port or it may be a byproduct of the port itself in the firmware of the LimeSDR. It’s usable in the upper bands, it just sounded scratchy (Note to the developers).

So - there you have it. If you feel up to it, remove the MN26 coil from the board (shown in red) and you can have two ports to use that act pretty similar for HF with great gain. As I have said before, more testing is needed before I can render a final assessment on this, and toward that I will continue to use this Wideband Port to study its characteristics.

Have fun with it…!

73 de Marty, KN0CK


80/75m This evening here in Iowa using the RX1_W Wideband Port:

CHEERS…! 73 de Marty, KN0CK


Looks good Marty, I will try this too. Is your antenna tuned to 4 MHz?

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Yep, I have a Hustler 6BVT with the 80m resonator so my vertical covers all bands pretty much with low VSWR and at 75m it’s tuned to be 1:1 match at 3970 MHz where I work regional nets on the weekends - the rest of 80/75m it’s in the 2:1 range (useful, but not perfect). Everywhere else (above 80/75m) it’s at least 1.5:1 or better clear to 10m.

Keep us advised of your progress there, Alex - 73,

de Marty, KN0CK

… pretty promising, Marty, thanks! 73 Nils, DK8OK

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Verified removing the coil on my RX1_W and using an old broadcast band filter I’m listening to local AM stations in Linux / gqrx (10e6 rate, 100MHz bw) just fine with little gain setting, off a 10Mhz dipole. Will try tonight with my 2-4MHz ham band filter. Looking good!

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I did the RX1_W mod too and getting acceptable signals above 3 MHz. The insane thing is the analog bandwidth setting 100 MHz… I hope Josh can figure this one out :grinning:

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On HF enable Analog filter and set the filter width to 60MHz.

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Thanks Simon! Indeed, it works with 60 MHz bandwidth setting :slight_smile:

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Zack told me to do that.

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I think the explanation is something like this…

The lowest frequency we can tune to using the PLL is 30 MHz. To receive HF we tune the PLL to 30 MHz, set the bandwidth to max (60 MHz) and use the NCO in the chip DSP to tune ± 30 MHz. Therefore, setting the analog bandwidth to 60 we can receive DC-60MHz, setting it to 30 MHz we can receive 15 - 45 MHz and so on…


So, the best hf performance is from rx1L or rx1W?
Is it possible to modify only rx2L and listen hf from there?

Yes, it is, if the software supports using the second receiver (gqrx doesn’t at the moment).

31m band going like gangbusters now, no filters, just a dipole for this band - listening to wwv 10Mhz and below, altho the numbers don’t quite make sense - Ubuntu 14.04, just updated to latest LimeSuite fw today. WWV is on 11.5Mhz at one point before walking down to zero in the receiver part - at one point it was 11.5 in the main window and -1.5 in the receiver window.

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Excuse me, user error - didn’t notice LNB LO was pre-set to 1.5 - remove that and the numbers are spot on.

Phew… :slight_smile:

For me the reception is quite fine down to about 3 MHz. I could also hear stations on 1.8 MHz and some MW broadcast.

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