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V 1.03 USB vs. LSB filters

Posted: Mon Sep 19, 2016 3:35 am
by JRBarrett
Greetings,

I am new to both the SDRPlay SDR, and SDRuno, having just received my new unit from HRO yesterday. It is working extremely well indeed!

I originally installed SDRuno version 1.02 on receipt, and have just installed the new version 1.03. I did not run 1.02 long enough to really notice if what I now see existed in 1.02 too.

After installing 1.03, there appears to be a disparity between the four preset filter bandwidths in LSB mode vs. USB, as shown in the receiver control panel. In LSB, the four presets are: 2000 Hz, 2200 Hz, 2400 Hz and 2700 Hz. In USB mode, the presets are: 2400, 2700, 12K and 24K.

I did note another post where it was mentioned that the maximum available bandpass in AM mode was increased beyond 12K in 1.03 by request - perhaps this is related?

It's not a problem, as I can manually set the bandwidths in the SP2 window.

The performance of the SDRPlay in both HF and VHF is outstanding. An excellent product!

Jim Barrett
KF2DA
Elmira, NY

Re: V 1.03 USB vs. LSB filters

Posted: Mon Sep 19, 2016 11:12 am
by sdrplay
Hello Jim,

The preset filters were adjusted in 1.03 to make them more usable. You can adjust them as you say. Do you have a specific use case in mind that requires a different filter to those available? There are also the USER ones as well.

Best regards,

SDRplay Support

Re: V 1.03 USB vs. LSB filters

Posted: Mon Sep 19, 2016 1:46 pm
by JRBarrett
sdrplay wrote:Hello Jim,

The preset filters were adjusted in 1.03 to make them more usable. You can adjust them as you say. Do you have a specific use case in mind that requires a different filter to those available? There are also the USER ones as well.

Best regards,

SDRplay Support
The reason it stood out is because USB/LSB are essentially the same mode, typically used for amateur or aeronautical communications, (LSB being used on the lower HF ham bands, and USB on the upper HF bands). It just seemed odd that LSB would have four relatively narrow filter presets, while USB would have two narrow and two wide presets.

Re: V 1.03 USB vs. LSB filters

Posted: Mon Sep 19, 2016 2:54 pm
by KM4JOJ
JRBarrett wrote: After installing 1.03, there appears to be a disparity between the four preset filter bandwidths in LSB mode vs. USB, as shown in the receiver control panel. In LSB, the four presets are: 2000 Hz, 2200 Hz, 2400 Hz and 2700 Hz. In USB mode, the presets are: 2400, 2700, 12K and 24K.
Hi Jim,

In 1.02, the filter widths were the same for both LSB and USB modes. In 1.03 as you noticed, USB has wider filter presets. How many digital modes to you see operate in LSB mode? All the digital activity that would require widths that wide are typically USB mode. Us hams are really the only ones using LSB for anything these days. All "utility" transmissions are typically USB; even CHU only transmits it's upper sideband (with carrier).

It makes sense to have wide USB presets but normal LSB presets. Like you found, if you really need wider LSB width you can just drag it in the SP2 window.

73,
-Jay/KM4JOJ

Re: V 1.03 USB vs. LSB filters

Posted: Mon Sep 19, 2016 7:39 pm
by JRBarrett
KM4JOJ wrote:
JRBarrett wrote: After installing 1.03, there appears to be a disparity between the four preset filter bandwidths in LSB mode vs. USB, as shown in the receiver control panel. In LSB, the four presets are: 2000 Hz, 2200 Hz, 2400 Hz and 2700 Hz. In USB mode, the presets are: 2400, 2700, 12K and 24K.
Hi Jim,

In 1.02, the filter widths were the same for both LSB and USB modes. In 1.03 as you noticed, USB has wider filter presets. How many digital modes to you see operate in LSB mode? All the digital activity that would require widths that wide are typically USB mode. Us hams are really the only ones using LSB for anything these days. All "utility" transmissions are typically USB; even CHU only transmits it's upper sideband (with carrier).

It makes sense to have wide USB presets but normal LSB presets. Like you found, if you really need wider LSB width you can just drag it in the SP2 window.

73,
-Jay/KM4JOJ
Ah, that makes perfect sense, thank you.

I'm very impressed with both the SDRPlay and SDRuno. I owned a Flex 5000 for two years, so have some previous exposure to SDR on HF, and I must say that the receive performance of the SDRPlay compares very favorably. I lost the Flex due to a very close lightning strike in 2012, and have been rather inactive on HF since, but the SDRPlay has renewed my interest in a big way. I have just ordered an Apache Anan 10 transceiver

73, Jim Barrett KF2DA

Re: V 1.03 USB vs. LSB filters

Posted: Thu Sep 22, 2016 12:25 am
by surely
Jay,

Seems like the proper way to implement this change (short of a gui redesign) would be to duplicate the filter values for both USB and LSB so that a band switch on HF Ham Bands would require, at most, a side-band mode change; not a side-band plus a bandwidth change. This would ensure uniformity with every other radio on the market. The changes, as implemented, have pretty much trashed the beauty and value of the SP2 window during mode changes on the HF Ham Bands without fiddling with the SP2 "zoom" button. I appreciate the need for a variety of filter widths but I don't I don't appreciate crippling existing functionality to further that end.

Keith