RX666 and RX888 as VHF receivers


David J Taylor
 

With prime interests only above 30 MHz, do the RX666 and RX888 offer me anything? OK, a 16-bit ADC rather than 12-bit or 14-bit in units like the RSP, RTL dongle or Airspy R2, or higher in the Airspy Discovery, so possibly more dynamic range (if the rest of the system is up to it).

Is anyone seriously considering these units as being preferred for VHF applications? To me they seem over the top, and likely lacking in support for other SDR software....

Comments?

Thanks,
David
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Conrad, PA5Y
 

On VHF you will get 10MHz BW and the performance is limited by the R820T2. I am not overly excited by this and because I am only interested in amateur bands and I know that I will get better performance from my high IP3 low PN transverters and my Perseus. It all depends what you want to do. SDRC V3 supports the RX666 and RX888, what other SDR software could you possibly need ?😉

Regards?

Conrad PA5Y


From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> on behalf of David J Taylor via groups.io <david-taylor@...>
Sent: 04 September 2020 06:11
To: SDR Radio <main@SDR-Radio.groups.io>
Subject: [SDR-Radio] RX666 and RX888 as VHF receivers
 
With prime interests only above 30 MHz, do the RX666 and RX888 offer me
anything?  OK, a 16-bit ADC rather than 12-bit or 14-bit in units like the
RSP, RTL dongle or Airspy R2, or higher in the Airspy Discovery, so possibly
more dynamic range (if the rest of the system is up to it).

Is anyone seriously considering these units as being preferred for VHF
applications?  To me they seem over the top, and likely lacking in support
for other SDR software....

Comments?

Thanks,
David
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv





David J Taylor
 

On VHF you will get 10MHz BW and the performance is limited by the R820T2. I am not overly excited by this and because I am only interested in amateur bands and I know that I will get better performance from my high IP3 low PN transverters and my Perseus. It all depends what you want to do. SDRC V3 supports the RX666 and RX888, what other SDR software could you possibly need ?😉

Regards?

Conrad PA5Y
==================================

Thanks.

73,
David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Zacharias Liangas
 

i feel very bad that the RX888 is limited to only 8 instead of the 32 as noticed..
I originally hoped that it could be OK for using it in  the top of hour  new listening..


Bob Dengler
 

At 9/3/2020 09:11 PM, you wrote:
With prime interests only above 30 MHz, do the RX666 and RX888 offer me
anything? OK, a 16-bit ADC rather than 12-bit or 14-bit in units like the
RSP, RTL dongle or Airspy R2, or higher in the Airspy Discovery, so possibly
more dynamic range (if the rest of the system is up to it).

Is anyone seriously considering these units as being preferred for VHF
applications? To me they seem over the top, and likely lacking in support
for other SDR software....
I bought mine strictly for UHF use. With my 12 bit Airspys at full BW I'm constantly having to throttle back the gains to the point the 12 dB SINAD is ~0.4 to 0.5 uV. Decimation does help a lot but then I can only see a few hundred kHz - might as well get a Funcube Dongle. The RSP1a is a bit better @ 14 bits but it's phase noise is considerably worse than the Airspys, so any gains in dynamic range are lost if there are any strong signals within ~60 kHz of the receive frequency.

I'm hoping the RX-888 will be the best of both worlds: 16 bit resolution & MHz BW. I only need 5 to 7 MHz so the R820T2 limitation won't bother me. My main concern is the dynamic range of the R820T2. If it ends up being a significant limitation I'll probably build my own downconverter to 20-30 MHz.

Bob NO6B


David J Taylor
 

From: Bob Dengler

I bought mine strictly for UHF use. With my 12 bit Airspys at full BW I'm constantly having to throttle back the gains to the point the 12 dB SINAD is ~0.4 to 0.5 uV. Decimation does help a lot but then I can only see a few hundred kHz - might as well get a Funcube Dongle. The RSP1a is a bit better @ 14 bits but it's phase noise is considerably worse than the Airspys, so any gains in dynamic range are lost if there are any strong signals within ~60 kHz of the receive frequency.

I'm hoping the RX-888 will be the best of both worlds: 16 bit resolution & MHz BW. I only need 5 to 7 MHz so the R820T2 limitation won't bother me. My main concern is the dynamic range of the R820T2. If it ends up being a significant limitation I'll probably build my own downconverter to 20-30 MHz.

Bob NO6B
======================================

Bob,

Yes, I had been thinking along similar lines, but one of my applications would be for 137 MHz weather satellite reception including Meteor M N2 reception where the decoder is quite closely tied in with SDR# and I can't see Airspy spending a lot of time writing a front-end for competing hardware! Meteor with SDR-Console is much more of a kludge as far as I know. Pagers are very strong here and only some tens of kHz away. The R820T2 strong signal performance is indeed an unknown.

With the RX-888 I'm buying a lot of capability I don't need, and I've seen other hardware which promised a lot but was very poorly supported and rather unreliable (Lime).

But I will be very interested to hear how you get on....

73,
David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Simon Brown
 

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of David
J Taylor via groups.io
Sent: 05 September 2020 08:17
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] RX666 and RX888 as VHF receivers

From: Bob Dengler

I bought mine strictly for UHF use. With my 12 bit Airspys at full BW I'm
constantly having to throttle back the gains to the point the 12 dB SINAD is
~0.4 to 0.5 uV. Decimation does help a lot but then I can only see a few
hundred kHz - might as well get a Funcube Dongle. The RSP1a is a bit better
@ 14 bits but it's phase noise is considerably worse than the Airspys, so
any gains in dynamic range are lost if there are any strong signals within
~60 kHz of the receive frequency.

I'm hoping the RX-888 will be the best of both worlds: 16 bit resolution &
MHz BW. I only need 5 to 7 MHz so the R820T2 limitation won't bother me.
My main concern is the dynamic range of the R820T2. If it ends up being a
significant limitation I'll probably build my own downconverter to 20-30
MHz.

Bob NO6B
======================================

Bob,

Yes, I had been thinking along similar lines, but one of my applications
would be for 137 MHz weather satellite reception including Meteor M N2
reception where the decoder is quite closely tied in with SDR# and I can't
see Airspy spending a lot of time writing a front-end for competing
hardware! Meteor with SDR-Console is much more of a kludge as far as I
know. Pagers are very strong here and only some tens of kHz away. The
R820T2 strong signal performance is indeed an unknown.

With the RX-888 I'm buying a lot of capability I don't need, and I've seen
other hardware which promised a lot but was very poorly supported and rather
unreliable (Lime).

But I will be very interested to hear how you get on....

73,
David GM8ARV




--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Alan
 

The R820T2 strong signal performance is indeed an unknown.
David,

This is used in Airspys so it's probably not bad.

73 Alan G4ZFQ


Max
 

I too am interested in VHF/UHF performance. Can someone with RX666 or 888 perhaps let us know even just a first opinion of performance, perhaps on VHF BFM 88-108 MHz, and 144MHz/432MHz?

I am assuming it should be quite respectable, but not found one post where anyone posted their experiences or screenshots.

Anyone RX666 or 888 owners out there to give an opinion, maybe compared to RTL-SDR or R2 for example, or perhaps compared to SDR Play RXs?

If it is half-way decent I will be ordering an RX888 and selling my RSP2Pro!

73

Max


David J Taylor
 

David,

This is used in Airspys so it's probably not bad.

73 Alan G4ZFQ
=====================================

Yes, I know, but I'm now using the Airspy Discovery which has a different architecture. Whether it's worth moving from the Discovery or Airspy R2 to the RX-888 is an unknown quantity!

I see that Simon has completed development on the RX-666, so where doe that leave the RX-888? Fully compatible?

73,
David GM8ARV
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Alan
 

I'm now using the Airspy Discovery which has a different
architecture.?? Whether it's worth moving from the Discovery or Airspy R2 to the RX-888 is an unknown quantity!

David,

Yes, but I think it is really a bandwidth question.
I do not think anything is going to significantly improve on the HF+ within it's frequency/bandwidth limitations. Probably much the same with the R2 despite it being 12 bits.

I see that Simon has completed development on the RX-666, so where
dose that leave the RX-888??? Fully compatible?

I'd guess that the VHF section will not be available?

73 Alan G4ZFQ


Max
 

Simon's screenshot here shows (I think I can just make it out) HF and VHF gain adjustment/slider? So hopefully has VHF coverage?

https://forum.sdr-radio.com:4499/viewtopic.php?f=57&t=159

I wish we would all settle on the Forum instead of hopping back and forward between IO and new Forum! It's getting time consuming and tiresome. Maybe time to close the IO Group?

Anyone?

Max


On Sat, Sep 5, 2020 at 11:09 AM, Alan wrote:
dose that leave the RX-888??? Fully compatible?

I'd guess that the VHF section will not be available?

73 Alan G4ZFQ


N2MS
 

Now that SDRC supports it would like to experiment with the RX-888.

Could anyone recommend a reliable supplier?

Mike B2NS

With the RX-888 I'm buying a lot of capability I don't need, and I've seen
other hardware which promised a lot but was very poorly supported and rather
unreliable (Lime).

But I will be very interested to hear how you get on....


Bjarne Mjelde
 

VHF (FM band) performance is quite similar to the RSPdx. 8 MHz though.
--
Bjarne Mjelde
arcticdx.blogspot.com
Remote receivers: 
arcticsdr.ddns.net:8073/
kongsdr.ddns.net:8074


David J Taylor
 

I wish we would all settle on the Forum instead of hopping back and forward between IO and new Forum! It's getting time consuming and tiresome. Maybe time to close the IO Group?

Anyone?

Max
===================================

I, for one, don't do "Forums". I want one program (e-mail in this case) where all communication takes place, and where I can store messages locally as required. I'm not going to have a Web browser with 20 different tabs open, having to visit each one several times an hour.

Cheers,
David
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


Alan G4ZFQ
 

I, for one, don't do "Forums".  I want one program (e-mail in this case) where all communication takes place, and where I can store messages locally as required.
David,

I agree but Simon has outvoted us:-)
The RSS feed helps. https://forum.sdr-radio.com:4499/app.php/feed
It's not perfect but you get all Forum messages sent by email, unfortunately often without context, delete or save. Click on a message and you go straight to the page on the Forum to respond.
RSS works on most email clients.

73 Alan G4ZFQ


Michael.2E0IHW
 

Think of President Shi and underlings who need to monitor this planet and the next...

I just delete and clear everything on the hour every hour - more or less

On Sa..05.September 19:50, Alan G4ZFQ wrote:
I, for one, don't do "Forums".  I want one program (e-mail in this case) where all communication takes place, and where I can store messages locally as required.



Max
 

David

I don't imagine I will persuade you, but top right of the forum main index window offers you "New Posts" and "Unread Posts", either of which will quickly in one window tell you what topics are active that you need to read.

Personally I gave up monitoring "groups" by email ages ago. I have enough email coming in without adding a deluge more when the web browser is so much more efficient. One "digest" email a day is plenty!

Anyway, I know this is a subject where everyone is adamant their method is the best so best to leave it there I guess! Just to say I have a feeling from the much reduced posting on here that most are migrating to the new forum and that this IO group will probably slowly decline. Only my opinion of course.

As an aside if you wish to manage multiple tabs in a browser very efficiently and easily (I certainly do it all the time) then for Chrome users try the truly excellent "Tabs Outliner" add-on. It makes saving and recalling dedicated groups of tabs a doddle. Makes "bookmarks" seem totally archaic. I personally could not now manage without it. I only use the free version. It works perfectly well, and no pesky ads by the way, but I have donated to the author as for me it is a "must have":

https://www.youtube.com/watch?v=OqjcrfKjobY
https://chrome.google.com/webstore/detail/tabs-outliner/eggkanocgddhmamlbiijnphhppkpkmkl?hl=en

Sorry for wandering off-topic.

73

Max



On Sat, Sep 5, 2020 at 05:01 PM, David J Taylor wrote:
I, for one, don't do "Forums". I want one program (e-mail in this case) where all communication takes place, and where I can store messages locally as required. I'm not going to have a Web browser with 20 different tabs open, having to visit each one several times an hour.

Cheers,
David
--
SatSignal Software - Quality software for you
Web: https://www.satsignal.eu
Email: david-taylor@...
Twitter: @gm8arv


N2MS
 

During the day I'm outside and have only access with a smartphone. I can read and save the pertinent emails from the group. Accessing the forum is cumbersome.

I like the group.

Mike N2MS

On 09/05/2020 11:59 AM David J Taylor via groups.io < david-taylor@...> wrote:


I wish we would all settle on the Forum instead of hopping back and forward
between IO and new Forum! It's getting time consuming and tiresome. Maybe
time to close the IO Group?

Anyone?

Max
===================================


Bob Dengler
 

At 9/5/2020 04:34 AM, you wrote:
Simon's screenshot here shows (I think I can just make it out) HF and VHF gain adjustment/slider? So hopefully has VHF coverage?

<https://forum.sdr-radio.com:4499/viewtopic.php?f=57&t=159>https://forum.sdr-radio.com:4499/viewtopic.php?f=57&t=159
Yes, but I only see 1 slider. Doesn't the R820T2 have 3 gain adjustments (LNA, mixer, & IF/VGA)? Wonder if that's all Simon decided to provide, or is that all that's accessible in the RX-666/888 hardware? My experience is that maximum optimization requires independent access of the LNA & VGA controls (I always leave the mixer at max, as it doesn't seem to offer anything extra after playing with the other two). Then again, maybe with the 16 bit ADC hopefully the front end gain settings will be less critical.

I wish we would all settle on the Forum instead of hopping back and forward between IO and new Forum! It's getting time consuming and tiresome. Maybe time to close the IO Group?
I've been posting all my new questions on the forum. Regardless of what I think, given how much time Simon devotes to SDRC I'm in favor of anything that makes his life easier.

Bob NO6B