The video is Beyond Exceptional. When talking to new Hams or wanna' bees, I always recommend a SDR and both a long antenna for HF and a 2m/44 vertical for VHF/UHF. Listen to the world for experience and the low cost is amazing. Besides the SDR receive functionality, the ability to open 4 (or more separate receive windows), you can then monitor 4 bands simultaneously and get more points in HF contests.
I’ve just acquired myself a NooElec SMArt SDR for a bit of messing around. I look forward to more of your videos on the setup and usage of it and other SDRs. I’m still interested in getting myself an RSP1B in the future and seeing where that takes me too.
@ If I wasn’t connecting it up in the same configuration as you were with the SDR switch and splitters would I necessarily need the LNA. My use case is receiving only for V and UHF. But I guess that if I could I’d use it for other bands too.
@@yetiradiovk4yt You do not 100% need the LNA and Attenuator but adding them will lower the initial Noise Figure of your entire RX Chain. Think of it as a very inexpensive upgrade to your RX. Yes it is 1 step up from the basic SDR running on SDR Console setup but it is an easy one to make and for short money. In the USA the TQP LNA is about $15 USD and a good Attenuator is about $30 USD. I could not RX EME signals without my LNAs as my RX Noise Figure would be too high.
Excellent job Hayden. I think I mentioned to you earlier when we exchanged emails that I think it's important for Hams to see how great the addition of an SDR to their station is. Also, to recognize that you can use an SDR for so much more than just adding a panadapter to your setup, remember its a fully blown, VERY configurable receiver.
Exactly what I need, but shipping kinda a bit on the expensive side to my home. I just got HF+ Discovery from giveaway (thanks Yousef and Airspy team ❤) and tried to integrate with my Dad's IC751A and saw this! HF+ Discovery RX sensitivity blown my mind, it's just so good and I haven't even update the firmware, lol. Thanks!
I agree every time I go to the post office. Often, for VK, ZL, JA and the middle east countries, my bill at the Post Office is way more than Shopify works out the shipping price to be. I gladly except the loss, although still with a sharp intake of breath, as at least you will be getting your SDR and SDRSwitch on the air.
Great video. I didn't realize that hooking up one of these SDR-switches was that involved. It will be interesting to see your test results using this in future videos.
Thanks Hayden have been looking for an SDR switch with good IL for 144/432 as I have built my own for 1296 MHz using a delay lines, microwave relays and splitters. I can hear way more using an SDR and SDR console is amazing. Still exploring microwave SDR options for 1GHz up - Adalm Pluto, Hack RF, Lime SDR etc with Tx capabilities as console supports TxR to 6GHz on these 👍🏼
@ excellent.. look forward to your experiments; Mat over at Tech Minds had SDR Console running with the AdalmPluto & LibreSDR hardware doing some satellite SSB tx tests on 13cm ~ GPS locked of course 👍🏼 the RX888 Mk2 SDR is an interesting broadband SDR view all of the HF band at once, it’s good up to 1.7GHz too
Thanks for this, Hayden! Great data. I've considered going the panadapter route before. Been interested in higher bandwidth SDRs of late. I've really thought about the Hermes Lite 2 as well. I was pretty surprised by that 20 percent decode difference you highlighted!
Very nice presentation on adding inline switches to your radio. I tried the MFJ switch with an older radio and it works but the loss is not good. I did not know these were available and thank you for sharing.
I loved this! I can see this setup to work very well with a rig that has no spectrum display. I have an SDR play that I may try it with an IC-7000. Keep up the awesome videos/info. 73 de WA3RSL
Great solution Hayden. I'm running a similar setup, but also found when I switched to a Hermes Lite 2 with Amplifier, running SDRs via a dedicated receive antenna was easier & seemed to give slightly better results. The question I have - Why can't manufacturers build this into their transceivers to save the hassle? Thanks for all your videos & what you share to the community. Keen to try & catch you on the air for a contact sometime also.
If you plan on getting an RTL-SDR, be mindful that the version 4 WILL be a limited run. Some of the chips they use for the version 4 are no longer in production. The v3 can do similarly well, and they are working on version 5
I have the mighty fine junk sdr switch and I have never had an issue with blowing my sdr as high in freq as 6 meters, and a drive of 100 watts. Had it for several years. Just lucky I guess, now that I said it it will smoke. I would like to upgrade,,,, this might do it.
Hi Hayden, First off, Happy New Year! Was this the video that you were working on the other night? You certainly did a great job of this, so much useful information. Personally, I don't know why someone would buy/use a cheap switch with something like an SDRPlay unit, sure if you bought a cheap dongle type SDR, it's easy to replace. But with something that costs quite a bit and comes from the other side of the world, that could get quite expensive. Thanks for a great video, once again.
Thanks Mike, Yes! I didn't think personally the video came out too well (I'm my own worst critic), but I'm glad that the information was helpful. More info coming soon on LNA's and measuring insertion loss & isolation.
GREAT content. I appreciate this. I have a FTDX-101D and the panadaptor is stupid - AWESOME radio, wonderful receive and filtering. Love it, but the panadapter sucks 🍑. I am going to do this! Thanks, Hayden! I'm going to have to rewatch this and take notes. So much info here!
These switches look fantastic. I wish there was a version with the Transmit path exposed too. We could put an amplifier or attenuator and amplifier in the transmit path only and it’ll be bypassed in receive. Maybe I could just use a CX800N DPDT relay. But I assume this has some sort of sequencer built in.
@@marvs4321 let’s say I want to share my wideband antenna not only with my transmitting rig, but maybe several other wideband receivers, like KiwiSDRs, Web-888, etc. I may not want my amplifier’s ATU in the receiver path because it could disrupt the receive performance on far away band. Additionally, let’s say I want to drive my amplifier with less power, I could insert an attenuator in the tx path without degrading receive performance.
Teriffic and I have spent yesterday getting sdrsonsole to work whilst my sdrswitch is on the way. One question….i run masthead preamps on 2m and 70cms via bias T from the amplifiers. Is there any reason I should not still do that with an LNA in the system?
The masthead amps are “LNA’s”. The noise figure of those will determine the overall system noise figure (plus anything before the preamps to antenna). So no need for additional amplifiers in the line 👍
@@mikesradiorepair That's crazy, I am Mr. frugal and shop many sites. I didn't really shop, I was just curious what the price difference was going to be from the Aussi Amazon to the US Amazon. I didn't go looking to buy, however that's KRA KRA.
@@HamRadioDX I have been noticing when I watch channels outside the US and they recommend stuff the price can really be different. It works both ways as well, sometimes we get it in the US for dollars and the folks outside the US can be a logarithmic expression more. Its Crazy. Then the shipping gets stupid as well, I just acquired some parts from Australia. The parts weighing about a half a kilo. The parts were $36 shipping calculated to $37 US standard post. I emailed and asked if that was right, to be informed it was. Its the same way shipping form the UK to the US. Its absurdly crazy.
very nice. Lots of great information. I have a SDRplay RSP 1 .I run separate with its one RX antenna . I don't use it much with my transceiver. I did use coaxial relay on input side to protect when TX , it puts a dummy load on SDR . 47 ohm 1/2 watt resistor. It works great. But I do not always have PTT line. Like using A HT or CB radio . On a separate antenna. I just switch off SDR when I TX near buy. I just worry about if my girlfriend TX from car in driveway or near buy . so far has not been a problem . I try to keep distance from transmitting antenna. I can see a RF sensing attenuator on SDR antenna could help. I have to make one. Having a seperate RX antenna can be very helpful. You can use a stereo headset and hear both at same time. This can sound neat as you get QSB . fades to one ear to another .DX commander does this on live stream . He sends both RX antennas over stereo audio . The loop on ground can be very helpful for RX during noisy conditions . 73
@Jerzel Very good question.... The purpose of an LNA is to set the initial Noise Figure of your RX chain. The Noise Figure is one of the most important figures in your RX chain. You only need enough gain to override the current NF of your RX. Too much gain will overdrive/saturate your RX. The TQP has about 26dB gain. You only need about 7dB for one RX or 15dB for Dual RX to Override your RXs and set their NF to the NF of the LNA. You need to "loose" the excess gain. This is a very normal procedure in VHF/UHF and EME.
That’s so strange I was looking at this exact website when trying to make a 2 m contact on FT8 . It seems like they’re all out of stock I sent them an email this morning hopefully they will be back in stock soon… this seems to be a great piece of kit a little expensive but like they always say you get what you pay for👍🏽👍🏽👍🏽👍🏽
One other thing Hayden, Could you please recommend a decent switchable 50Ω Attenuator box like you had in this video? These things used to be everywhere a few years ago, now really good ones are quite hard to find. Cheers, Mike T.
I have the 3-BNC version of that SDR switch; it’s great. I don’t understand something in your presentation: the use of the splitter. Why listen on both the SDR and the transceiver? I used this set up to upgrade my FT-891 so maybe I’m looking at this from a different perspective.
You cannot listen on both the radio and the SDR at the same time with the 3-BNC version. The radio connected to the XCV port is switched out during receive. (unless you used a splitter and then fed the output into a 2nd rx only antenna port on your radio) Being able to compare you rig's receiver performance to the SDR can help you decide which one is best on a particular band or in a particular mode. You can do simultaneous comparisons and tweak your SDR/Xcvr setttings.
@@marvs4321 regarding the 3-BNC variants, that’s exactly what I said. I have the 3-BNC version because I don’t understand the desire to listen on both. The ad hoc comparisons is an interesting use case. Thanks for sharing that. I used a coax switch when I first got it to compare reception between them. The difference between my RSPdx-R2 and the 891 was so significant, especially with the ease of antenna switching, notching, and filtering with an SDR, I never checked again. But that’s likely a different experience on something like a 7610.
Not only can you listen on both and decide which one to receive on - as @marvs4321 pointed out - you can use an SDR that rivals some of the best receivers out there, such as the Airspy HF Discovery+... to listen to the same frequency - or multiple receivers at once. The IC-7300 for example has the capability to listen to one thing at a time. With an SDR in line and SDR console, you can listen up to 24 receivers at once. With an SDR that covers multiple MHz of bandwidth you can listen to almost the whole HF band. If you're doing digital with WSJT-X you can decode FT8, WSPR or any mode across the whole band. For me, I can listen to the FM repeaters on 10m (without needing to "scan" them), SSB, FT8 and WSPR all at the same time on 10m. That would need several radios to do otherwise. Then with Omni-Rig I can easily switch to the active channel or frequency. All pretty powerful!
Yeah that’s why I use the SDR 100% and not the transceiver. Splitting the received signals to multiple SDRs could be interesting but that’s solved better with the 3-BNC variants. Splitting so your transceiver can hear the signal doesn’t seem useful *unless you have a really nice transceiver*, which I do not.
Very simply, Yes. You install your SDRSwitch between your Rig and Your Amplifier (ATU) so all that matters is the Isolation based on how much power you are using to drive your amplifier. I run them on both my HF station and my 2M EME station. On 2M EME I run 1.5KW but only need 25W drive so the SDRSwitch has 25W running through it and all the Isolation calculations, the number that matters, are based on 25W. The 1.5KW is after the SDRSwitch, LNA, SDR so has no effect on them.
@@Knarf14 If you are using the LNA with the 4BNC SDRSwitch RXin RXout you want to disconnect the battery. You will use a 12VDC-5VDC Buck converter (for the TQP LNA) to power the LNA from the back of the SDRSwitch. When you TX the 12VDC is switched off and therefore your LNA is turned off in order to add a further layer of protection to your RX chain.
@@Knarf14 The TQP seems to run on the 5VDC whilst DC power is connected and defaults to the battery when the 5VDC is removed. It is a nice idea for when you want to plug it in up the tower for testing and do not want to run DC outside just for a quick test
Given that your results and others' both demonstrate rx superiority of the external Sdr rx setup over the transciever's internal capability, the obvious question is why is it so. None of the mainstream transceivers could be labeled as deaf or noisy. Perhaps by moving the LNA and other bits to the transciever's rx chain, an answer will be found.
The SDRSwitch has the advantage that the LNA is added to not just into the SDR path, but also the transceiver. Results are clear that having the SDR receiving directly rather than IF tap is much better too. I guess it's also going to vary from radio to radio. I also don't look at "SNR" so much in WSJT-X, but when they do decode, the Nooelec SDR is usually a dB or so behind the IC-7610. However the 7610 brings in on average more decodes than the Nooelec on 10m.
@@1958johndeere620 Yes. Your LNA sets the Noise Figure for your entire RX chain, Remember with LNAs (Pre-Amps) we do not want much gain, just enough to override the front end Noise Figure of the Rig and/or SDR. What we care about is the Noise Figure. With the RXin RXout the LNA will set the initial Noise Figure for both your Rig and your SDR. In EME you might have a 29dB 0.4dB NF LNA at the start of your RX Chain and then add 20dB off attenuation to get rid of the excess gain and no overload your RX.
Just one I had lying around - it's pretty old. www.rfparts.com/sa-50-texscan-50-ohm-attenuator-used-excellent-condition.html But any step attenuator would work for the frequency range that is 50 ohms. Fixed attenuators will work - but more annoying if you need to switch attenuation in and out.
@randykitchleburger2780 They are pretty much identical to 450MHz. I just chose that as a cut-off frequency. indeed they are good up to the 902 band although at 902 the isolation on the relays is a little low for my liking but they are still the standard relay used in LNAs up to 1296.
I’m fundamentally confused. Why would anybody want to tap into their IF just to feed an SDR? Is it to protect the SDR from the transmitter? And that’s why an “SDR Switch” is an alternative?
I cannot give you a good answer to that as there are so many negatives in doing so. Some people want to open their radios and Tap the IF in order to access the signal and that is fine. Alas you are no longer getting the RAW RF signal to your SDR but instead a signal that has been interfered with by your Rig. You are often limited to a 3kH wide bandpass when you IF Tap which seems a shame for an SDR such as the RX-888 MK11 which as a 31 MHz Bandpass which allows you to see the entire HF band at once.
The video is Beyond Exceptional. When talking to new Hams or wanna' bees, I always recommend a SDR and both a long antenna for HF and a 2m/44 vertical for VHF/UHF. Listen to the world for experience and the low cost is amazing. Besides the SDR receive functionality, the ability to open 4 (or more separate receive windows), you can then monitor 4 bands simultaneously and get more points in HF contests.
I agree, it's great that SDRs are so affordable these days, and they really open up so many possibilities. Thank you for the awesome comment!
Literally just bought one before Christmas. Paul is amazingly helpful. I completely recommend these to anyone.
Paul is an awesome guy!
I have been extremely happy with mine. Lower loss than the MFJ unit I previously had.
I’ve just acquired myself a NooElec SMArt SDR for a bit of messing around. I look forward to more of your videos on the setup and usage of it and other SDRs.
I’m still interested in getting myself an RSP1B in the future and seeing where that takes me too.
Thanks Ben! More videos coming soon
@ If I wasn’t connecting it up in the same configuration as you were with the SDR switch and splitters would I necessarily need the LNA.
My use case is receiving only for V and UHF. But I guess that if I could I’d use it for other bands too.
@@yetiradiovk4yt You do not 100% need the LNA and Attenuator but adding them will lower the initial Noise Figure of your entire RX Chain. Think of it as a very inexpensive upgrade to your RX. Yes it is 1 step up from the basic SDR running on SDR Console setup but it is an easy one to make and for short money. In the USA the TQP LNA is about $15 USD and a good Attenuator is about $30 USD. I could not RX EME signals without my LNAs as my RX Noise Figure would be too high.
Excellent job Hayden. I think I mentioned to you earlier when we exchanged emails that I think it's important for Hams to see how great the addition of an SDR to their station is. Also, to recognize that you can use an SDR for so much more than just adding a panadapter to your setup, remember its a fully blown, VERY configurable receiver.
Fully blown configurable receiver x 24 haha! Good stuff thanks mate
Exactly what I need, but shipping kinda a bit on the expensive side to my home. I just got HF+ Discovery from giveaway (thanks Yousef and Airspy team ❤) and tried to integrate with my Dad's IC751A and saw this! HF+ Discovery RX sensitivity blown my mind, it's just so good and I haven't even update the firmware, lol. Thanks!
I agree every time I go to the post office. Often, for VK, ZL, JA and the middle east countries, my bill at the Post Office is way more than Shopify works out the shipping price to be. I gladly except the loss, although still with a sharp intake of breath, as at least you will be getting your SDR and SDRSwitch on the air.
Great video. I didn't realize that hooking up one of these SDR-switches was that involved. It will be interesting to see your test results using this in future videos.
Thanks mate - I’ve got some great tests coming up using this!
Thanks Hayden have been looking for an SDR switch with good IL for 144/432 as I have built my own for 1296 MHz using a delay lines, microwave relays and splitters. I can hear way more using an SDR and SDR console is amazing. Still exploring microwave SDR options for 1GHz up - Adalm Pluto, Hack RF, Lime SDR etc with Tx capabilities as console supports TxR to 6GHz on these 👍🏼
Thanks mate! SDR Console is truly awesome! Microwave SDR’s is next for me too!
@ excellent.. look forward to your experiments; Mat over at Tech Minds had SDR Console running with the AdalmPluto & LibreSDR hardware doing some satellite SSB tx tests on 13cm ~ GPS locked of course 👍🏼 the RX888 Mk2 SDR is an interesting broadband SDR view all of the HF band at once, it’s good up to 1.7GHz too
Thanks for this, Hayden! Great data. I've considered going the panadapter route before. Been interested in higher bandwidth SDRs of late. I've really thought about the Hermes Lite 2 as well. I was pretty surprised by that 20 percent decode difference you highlighted!
Thanks! I’m going to do a comparison video of my own soon!
Very nice presentation on adding inline switches to your radio. I tried the MFJ switch with an older radio and it works but the loss is not good. I did not know these were available and thank you for sharing.
I loved this! I can see this setup to work very well with a rig that has no spectrum display. I have an SDR play that I may try it with an IC-7000. Keep up the awesome videos/info. 73 de WA3RSL
Glad you enjoyed it, it's great to see others trying it out! 73's
Those are really good pro tips, thanks HRDX.
Great solution Hayden.
I'm running a similar setup, but also found when I switched to a Hermes Lite 2 with Amplifier, running SDRs via a dedicated receive antenna was easier & seemed to give slightly better results.
The question I have - Why can't manufacturers build this into their transceivers to save the hassle?
Thanks for all your videos & what you share to the community.
Keen to try & catch you on the air for a contact sometime also.
Thanks for the video Hayden. I’ve got an SDRplay receiver that I wanted to connect to the antenna my 7300 is connected to.
Me to, an sdrplay-duo
If you plan on getting an RTL-SDR, be mindful that the version 4 WILL be a limited run. Some of the chips they use for the version 4 are no longer in production. The v3 can do similarly well, and they are working on version 5
I have the mighty fine junk sdr switch and I have never had an issue with blowing my sdr as high in freq as 6 meters, and a drive of 100 watts. Had it for several years. Just lucky I guess, now that I said it it will smoke. I would like to upgrade,,,, this might do it.
Hi Hayden,
First off, Happy New Year!
Was this the video that you were working on the other night?
You certainly did a great job of this, so much useful information.
Personally, I don't know why someone would buy/use a cheap switch with something like an SDRPlay unit, sure if you bought a cheap dongle type SDR, it's easy to replace.
But with something that costs quite a bit and comes from the other side of the world, that could get quite expensive.
Thanks for a great video, once again.
Thanks Mike,
Yes! I didn't think personally the video came out too well (I'm my own worst critic), but I'm glad that the information was helpful. More info coming soon on LNA's and measuring insertion loss & isolation.
GREAT content. I appreciate this. I have a FTDX-101D and the panadaptor is stupid - AWESOME radio, wonderful receive and filtering. Love it, but the panadapter sucks 🍑. I am going to do this! Thanks, Hayden! I'm going to have to rewatch this and take notes. So much info here!
Thanks mate! More info to come and demos/tests
my best guess is the noelec and other RTL-SDR receivers, are about as good as a state of the art receiver... from around 1950-60
@willgilliam9053 I think on 6M and up you are going to be very surprised.
Happy new year Hayden
Thank you, Happy New Year to you too mate!
I use these SDR's to align my antennas and listen to digital
I have so many gadgets for my radios including the SDR switch but still have no time to set these up. I might just wind up dropping them on Ebay.
These switches look fantastic. I wish there was a version with the Transmit path exposed too. We could put an amplifier or attenuator and amplifier in the transmit path only and it’ll be bypassed in receive. Maybe I could just use a CX800N DPDT relay. But I assume this has some sort of sequencer built in.
I'm not sure why you'd want the transmit path exposed? you'd have to explain that one better.
@@marvs4321 let’s say I want to share my wideband antenna not only with my transmitting rig, but maybe several other wideband receivers, like KiwiSDRs, Web-888, etc. I may not want my amplifier’s ATU in the receiver path because it could disrupt the receive performance on far away band. Additionally, let’s say I want to drive my amplifier with less power, I could insert an attenuator in the tx path without degrading receive performance.
2:02 i cant agree more i HIGLY recomend the airspy hf + discovery
apsoluty wort its price
The only issue with it for me is that it's lacking 6 metres... but apart from that I've only heard good things from everyone.
Teriffic and I have spent yesterday getting sdrsonsole to work whilst my sdrswitch is on the way. One question….i run masthead preamps on 2m and 70cms via bias T from the amplifiers. Is there any reason I should not still do that with an LNA in the system?
The masthead amps are “LNA’s”.
The noise figure of those will determine the overall system noise figure (plus anything before the preamps to antenna).
So no need for additional amplifiers in the line 👍
I was expecting to see it in action and how the cheap sdr compared to the 7610 😢
Wonder how this would compete with a stand alone Apache Labs Anan G-2 in terms of performance
Lol - this morning here in the USA that LNA is $107.82 US W/O Battery on Amazon.
It's $15.35 on eBay without battery.
@@mikesradiorepair That's crazy, I am Mr. frugal and shop many sites. I didn't really shop, I was just curious what the price difference was going to be from the Aussi Amazon to the US Amazon. I didn't go looking to buy, however that's KRA KRA.
I thought I linked to the Amazon.com site? Either way on Aliexpress it's only $15
@@HamRadioDX I have been noticing when I watch channels outside the US and they recommend stuff the price can really be different. It works both ways as well, sometimes we get it in the US for dollars and the folks outside the US can be a logarithmic expression more. Its Crazy. Then the shipping gets stupid as well, I just acquired some parts from Australia. The parts weighing about a half a kilo. The parts were $36 shipping calculated to $37 US standard post. I emailed and asked if that was right, to be informed it was. Its the same way shipping form the UK to the US. Its absurdly crazy.
very nice. Lots of great information. I have a SDRplay RSP 1 .I run separate with its one RX antenna . I don't use it much with my transceiver. I did use coaxial relay on input side to protect when TX , it puts a dummy load on SDR . 47 ohm 1/2 watt resistor. It works great. But I do not always have PTT line. Like using A HT or CB radio . On a separate antenna. I just switch off SDR when I TX near buy. I just worry about if my girlfriend TX from car in driveway or near buy . so far has not been a problem . I try to keep distance from transmitting antenna. I can see a RF sensing attenuator on SDR antenna could help. I have to make one. Having a seperate RX antenna can be very helpful. You can use a stereo headset and hear both at same time. This can sound neat as you get QSB . fades to one ear to another .DX commander does this on live stream . He sends both RX antennas over stereo audio . The loop on ground can be very helpful for RX during noisy conditions . 73
A loop antenna is a great idea for noise rejection, I might have to try that out for some of my testing.
Thanks for this but confused, why amplify the signal and then immediately attenuate it? thanks :)
@Jerzel Very good question.... The purpose of an LNA is to set the initial Noise Figure of your RX chain. The Noise Figure is one of the most important figures in your RX chain. You only need enough gain to override the current NF of your RX. Too much gain will overdrive/saturate your RX. The TQP has about 26dB gain. You only need about 7dB for one RX or 15dB for Dual RX to Override your RXs and set their NF to the NF of the LNA. You need to "loose" the excess gain. This is a very normal procedure in VHF/UHF and EME.
@@paulnewcombe5631 makes sense, appreciate the explanation. cheers :)
That’s so strange I was looking at this exact website when trying to make a 2 m contact on FT8 . It seems like they’re all out of stock I sent them an email this morning hopefully they will be back in stock soon… this seems to be a great piece of kit a little expensive but like they always say you get what you pay for👍🏽👍🏽👍🏽👍🏽
Paul says that stock is arriving soon!
One other thing Hayden,
Could you please recommend a decent switchable 50Ω Attenuator box like you had in this video?
These things used to be everywhere a few years ago, now really good ones are quite hard to find.
Cheers,
Mike T.
The one I used is an old one I found somewhere. There are good step ones on eBay or also check out RFparts.com
I have the 3-BNC version of that SDR switch; it’s great. I don’t understand something in your presentation: the use of the splitter. Why listen on both the SDR and the transceiver? I used this set up to upgrade my FT-891 so maybe I’m looking at this from a different perspective.
You cannot listen on both the radio and the SDR at the same time with the 3-BNC version. The radio connected to the XCV port is switched out during receive. (unless you used a splitter and then fed the output into a 2nd rx only antenna port on your radio) Being able to compare you rig's receiver performance to the SDR can help you decide which one is best on a particular band or in a particular mode. You can do simultaneous comparisons and tweak your SDR/Xcvr setttings.
@@marvs4321 regarding the 3-BNC variants, that’s exactly what I said. I have the 3-BNC version because I don’t understand the desire to listen on both.
The ad hoc comparisons is an interesting use case. Thanks for sharing that. I used a coax switch when I first got it to compare reception between them. The difference between my RSPdx-R2 and the 891 was so significant, especially with the ease of antenna switching, notching, and filtering with an SDR, I never checked again. But that’s likely a different experience on something like a 7610.
Not only can you listen on both and decide which one to receive on - as @marvs4321 pointed out - you can use an SDR that rivals some of the best receivers out there, such as the Airspy HF Discovery+... to listen to the same frequency - or multiple receivers at once.
The IC-7300 for example has the capability to listen to one thing at a time. With an SDR in line and SDR console, you can listen up to 24 receivers at once. With an SDR that covers multiple MHz of bandwidth you can listen to almost the whole HF band.
If you're doing digital with WSJT-X you can decode FT8, WSPR or any mode across the whole band.
For me, I can listen to the FM repeaters on 10m (without needing to "scan" them), SSB, FT8 and WSPR all at the same time on 10m. That would need several radios to do otherwise.
Then with Omni-Rig I can easily switch to the active channel or frequency. All pretty powerful!
Yeah that’s why I use the SDR 100% and not the transceiver. Splitting the received signals to multiple SDRs could be interesting but that’s solved better with the 3-BNC variants. Splitting so your transceiver can hear the signal doesn’t seem useful *unless you have a really nice transceiver*, which I do not.
Many thanks for this. You've probably saved me ~$3,500. Much appreciated!
Glad I could help!
WHat is the model of Step Attenuator you have?
@melming8751 I use the JFW 50DR-109 DC - 3GHz 30dB (10dB/1 dB) Step Attenuator - Adjustable/Variable in my shack. $30 USD from Ebay USA
SDR w LNA
I run a kw on vhf and uhf will the lna or the switch be ok even running them before the amplifier?
Very simply, Yes. You install your SDRSwitch between your Rig and Your Amplifier (ATU) so all that matters is the Isolation based on how much power you are using to drive your amplifier. I run them on both my HF station and my 2M EME station. On 2M EME I run 1.5KW but only need 25W drive so the SDRSwitch has 25W running through it and all the Isolation calculations, the number that matters, are based on 25W. The 1.5KW is after the SDRSwitch, LNA, SDR so has no effect on them.
@ i also see the lna comes with battery and without , the one without just needs to be always plugged in ?
@@Knarf14 If you are using the LNA with the 4BNC SDRSwitch RXin RXout you want to disconnect the battery. You will use a 12VDC-5VDC Buck converter (for the TQP LNA) to power the LNA from the back of the SDRSwitch. When you TX the 12VDC is switched off and therefore your LNA is turned off in order to add a further layer of protection to your RX chain.
@ so does it make sense to use the battery one with a rx only radio ? I use other receivers for monitoring
@@Knarf14 The TQP seems to run on the 5VDC whilst DC power is connected and defaults to the battery when the 5VDC is removed. It is a nice idea for when you want to plug it in up the tower for testing and do not want to run DC outside just for a quick test
Given that your results and others' both demonstrate rx superiority of the external Sdr rx setup over the transciever's internal capability, the obvious question is why is it so.
None of the mainstream transceivers could be labeled as deaf or noisy. Perhaps by moving the LNA and other bits to the transciever's rx chain, an answer will be found.
The SDRSwitch has the advantage that the LNA is added to not just into the SDR path, but also the transceiver.
Results are clear that having the SDR receiving directly rather than IF tap is much better too. I guess it's also going to vary from radio to radio.
I also don't look at "SNR" so much in WSJT-X, but when they do decode, the Nooelec SDR is usually a dB or so behind the IC-7610. However the 7610 brings in on average more decodes than the Nooelec on 10m.
@@HamRadioDX Interesting, it pre amps the RX signal to the transceiver as well?? With the LNA installed of coarse.
@@1958johndeere620 Yes. Your LNA sets the Noise Figure for your entire RX chain, Remember with LNAs (Pre-Amps) we do not want much gain, just enough to override the front end Noise Figure of the Rig and/or SDR. What we care about is the Noise Figure. With the RXin RXout the LNA will set the initial Noise Figure for both your Rig and your SDR. In EME you might have a 29dB 0.4dB NF LNA at the start of your RX Chain and then add 20dB off attenuation to get rid of the excess gain and no overload your RX.
Not sure what that's all about hi, I simply use a morse key and my ears, long haul dx in the log, every single day.
Great vid! Thx!
Happy New Year Hayden:
Maybe you mentioned this in the video and I missed it, but what SDR software were you using? Thanks!
Currently a Nooelec V5 Smart SDR. $35 on Amazon... I also have an Airspy Mini and I have just received a RX-888 MKII - video coming soon on that
@@HamRadioDX No - I mean the software on your computer. I just picked up a Nooelec V5. :)
What is the attenuator you are using?
Just one I had lying around - it's pretty old.
www.rfparts.com/sa-50-texscan-50-ohm-attenuator-used-excellent-condition.html
But any step attenuator would work for the frequency range that is 50 ohms.
Fixed attenuators will work - but more annoying if you need to switch attenuation in and out.
What my yaesu frg 7 sdr nice one
0-450Mhz, close but what about GMRS for us US users! 470MHz, I wonder what the numbers look like at 470MHz.
@randykitchleburger2780 They are pretty much identical to 450MHz. I just chose that as a cut-off frequency. indeed they are good up to the 902 band although at 902 the isolation on the relays is a little low for my liking but they are still the standard relay used in LNAs up to 1296.
@@paulnewcombe5631 Thanks! I appreciate your reply.
I’m fundamentally confused. Why would anybody want to tap into their IF just to feed an SDR? Is it to protect the SDR from the transmitter? And that’s why an “SDR Switch” is an alternative?
I cannot give you a good answer to that as there are so many negatives in doing so. Some people want to open their radios and Tap the IF in order to access the signal and that is fine. Alas you are no longer getting the RAW RF signal to your SDR but instead a signal that has been interfered with by your Rig. You are often limited to a 3kH wide bandpass when you IF Tap which seems a shame for an SDR such as the RX-888 MK11 which as a 31 MHz Bandpass which allows you to see the entire HF band at once.
Crack on, mate!
Thanks Jeem!
You can build this your self for a fraction of the price. Its easy to do.