Q for Mad_Lad re: signal strengths between Yaesu and Kiwi?

Popoutman

Here's a question aimed at Mad_Lad, but obviously answerable by anyone with relevant experience.

Which would be more likely to pull a contact out of the background noise - an SDR such as a KiwiSDR or HF+ Discovery with half-decent antenna, or e.g. a Yaesu FT891 with half-decent antenna? Is there much difference in the sound quality possible? I've no experience yet to compare the receive strengths of "proper" HF antennas compared to miniwhips or my Active-Antennas.eu aaa-1c that I'm running, and I'm curious as to the experience of others.

I'm doing pie-in-the-sky ideas for my setup post-license (whenever that happens) where I might be better off using something like my Airspy HF+ and SDR Console V3's noise reduction algorithms for the receive side, and transmitting with the actual HF radio, and using CAT control to keep both sides concurrent. Assuming of course that the SDR could pull lower strength signals out of the murk, and then being able to use a PC to clean up the noise. Of course, panadapter modification to the radio might be a clean and safe way of doing this.

Currently toying with at an FT891 (on offer with €80 cash back from Yaesu at wimo.com at the moment), and something like the DX Commander compound 1/4 wave vertical antenna setup (https://www.m0mcx.co.uk/store/products/multi-band-80m-6m-hf-antenna-p-ale-compliant-antenna-survival-prep-sota-kit/) for a no-tune antenna for the bands I'm listening to at the moment. I'm currently building a QRP antenna tuner for curiosity purposes to use with the SDRs, bu tthat's not got the capability of handling more than about 15w of transmission.

Of course if going portable makes all of that a moot point, when it's just easier to have the HF radio on its own and not have to bring a laptop and second antenna

Popoutman

Popoutman wrote: »

Here's a question aimed at Mad_Lad, but obviously answerable by anyone with relevant experience.

Which would be more likely to pull a contact out of the background noise - an SDR such as a KiwiSDR or HF+ Discovery with half-decent antenna, or e.g. a Yaesu FT891 with half-decent antenna? Is there much difference in the sound quality possible? I've no experience yet to compare the receive strengths of "proper" HF antennas compared to miniwhips or my Active-Antennas.eu aaa-1c that I'm running, and I'm curious as to the experience of others.

I'm doing pie-in-the-sky ideas for my setup post-license (whenever that happens) where I might be better off using something like my Airspy HF+ and SDR Console V3's noise reduction algorithms for the receive side, and transmitting with the actual HF radio, and using CAT control to keep both sides concurrent. Assuming of course that the SDR could pull lower strength signals out of the murk, and then being able to use a PC to clean up the noise. Of course, panadapter modification to the radio might be a clean and safe way of doing this.

Currently toying with at an FT891 (on offer with €80 cash back from Yaesu at wimo.com at the moment), and something like the DX Commander compound 1/4 wave vertical antenna setup (https://www.m0mcx.co.uk/store/products/multi-band-80m-6m-hf-antenna-p-ale-compliant-antenna-survival-prep-sota-kit/) for a no-tune antenna for the bands I'm listening to at the moment. I'm currently building a QRP antenna tuner for curiosity purposes to use with the SDRs, bu tthat's not got the capability of handling more than about 15w of transmission.

Of course if going portable makes all of that a moot point, when it's just easier to have the HF radio on its own and not have to bring a laptop and second antenna

Only seeing this now

It's a no brainer, if you intend getting your license and working portable then the FT-891 is a fantastic radio, Good receiver and great NR, even setting it to 1 will make a big difference, I do find the sound via the internal speaker is not so good but I mostly listen with headphones even working portable. And the 891 is more than capable to be used as a base rig even if it's a bit awkward to use with the menus until you are familiar with them. I use the 891 with FlRig and it makes using the radio a lot easier.

You will appreciate having the 100 watts when you need, start with 20 and crank it up if you're not getting anywhere.

A panadapter will attenuate your signals up to 3 or 4 db I've read unless using the panadapter for the ic-7300 The PTRX-7300 there is no attenuation at all.

You should be able to find the 891 at a good price 2nd hand, I got mine 2nd hand and updated the Firmware.

If you like SDR then you could get the 891 and save up for an Expert Electronics SUN SDR2 DX. It seems to be a fantastic 100 watt SDR that can work remotely and run on Linux and Apple too. I would skip the IC-7300 because it's not a proper SDR to begin with but it is a decent radio but once you see the waterfall on a big screen you won't want to go back to a tiny screen. Point and click on the computer monitor, adjust bandwidth and frequency with the mouse wheel, it's great.

The Airspy will have better nr than the Kiwi or FT-891 when using sdr Sharp I find sdr sharp nr better than SDR COnsole but I use SDR console with the PTRX-7300 Panadapter because I'm not sure if it's even possible to use sdr sharp with the panadapter to sync the sdr to the radio but even with sdr console the nr is a lot better than the 7300 and again, I listen mostly with headphones, I find this is much better especially for weak signals.

I wouldn't buy the Kiwi SDR unless you intend investing in a proper receiving antenna like the Bonito MegaDipol, so it's a very expensive combination. A ham antenna will overload the bejesus out of the kiwi because there is no form of RF gain control, you could of course build your own attenuator. The Bonito MegaDipol is a superb receiving antenna though. I take it you have use my 2 Kiwi's with the Megaloop and MegaDipol ? The Kiwi is really for those who want their radio online and accessible to anyone anywhere.

The DX commander antenna gets good reviews. Should be good for DX but you'll still need an antenna for more local use and I think the myantennas.com EFHW 8010 is an excellent antenna, 40 meters long though and it needs to be as high as possible, I even get good DX on mine, get to South America several times, U.S, Canada and Sydney once because I was on at the right time. Got to Barbados the other day on 15 meters. Impressive antenna.

I have my EFHW-8010 mounted in a kind of inverted L, UNUN close to ground, grounded there at base of tree, Goes up about 20 feet in that tree, turns North to another tree around 40 feet then East to another tree around 55-60 feet High, this installation works very well for me.

With any radio and antenna setup, you need to be in the quietest location possible free from man made noise as this can wipe out a tonne of weak signals, you need to keep interfering sources away from your antenna
Look on youtube and see the Sun SDR 2 DX in action.

Popoutman

Cheers for the inputs regarding the radio comparisons - truly useful.

I have actually got x2 Kiwis at the moment.

The Limerick one is being fed by a cheapie Chinese MLA-30 antenna that I swapped out the utterly terrible bias-t feeder it comes with with a known-working one, and I am not using the thin wire loop on it at all either/ I rigged up two two-meter lengths of 0.75^2 cable as a dipole. For a good while I had it vertical, then a storm blew it horizontal, and it was left on the edge of the lawn in that configuration. I'm mostly running WSPR listening into a Pi4 on that, and uploading under SWLIO52RP to the wsprnet site. I'm averaging in the top 40 to 80 worldwide with that setup. There's a lot of loops through -31 type toroids to dampen down the fairly high RFI coming in on the 30m of coax feeding from the antenna.

The second Kiwi is in Zurich, in the attic on the top floor apartment, maybe 40m above ground level or so. The antenna on that is an Amplified-Antennas.eu AAA-1c, with four 2m lengths of alu/pet combination pipe, in a double crossed loop configuration. For an indoors antenna that's really performing pretty well, again with WSPR listeners active, but generally another 30 or so places down the table under SWLJN47FJ. Quite RF noisy for sure, but not as bad as some places can be. Pretty good in 40m/20m reception. I swapped the Beaglebone it came with for a Beaglebone AI to get the multiple DRM decodings and built-in wifi, was a fun project doing that update. I'll likely get involved with testing the KiwiPi idea of using a Pi3 or Pi4 instead of Beaglebone.

Definitely getting a taste for what I want at least, and spending a fair amount of time just listening to the conversations but most of the conversations here at the moment are naturally enough German, Russian and Italian. I can still pick up east coast US conversations at times, using an antenna tee to split the AAA-1c to the Kiwi and my HF+.

I have a decent handful of SDRs though.. Airspy HF+ Discovery, Airspy R2 and Spyverter, two Airspy Minis (as ADSB listeners), an SDRPlay RSP1a, a Radarbox adsb dongle, and x3 RTL-SDR dongles. Oh and a HackRF as well, though no tranmissions on licensed bands yet for me on that.. I've also recently built the QRPGuys EzPi 20m Pi hat, so will be interesting to see how well that works.

I've built a handful of wire-based antennas with some success. QRPGuys kits: no-tune EFHW, a randomwire with balun, a 20/30/40 trapped EFHW that I'm trying to get built right, and their ez-tune two capacitor kit as well. Previously I had moderate results with homebuilt dipoles and randomwires with ununs, a very usefu learning step. I'm testing with a NanoVNA-H - and that is definitely one of the most useful and interesting things I have got for learning how to antenna well. Nice to know I can get an EFHW down to SWR of 1.005 - bodes well for QRP work when finally licensed.

Just waiting on some work contract stuff to come through before I shell out for a rig, but definitely leaning towards the -891 especially at the current prices. And waiting for the authorities to reopen the admissions for the licensing exam, definitely can't wait for that.

Ah yes, I forgot you had a kiwi.

Interesting, I didn't know there was a Beaglebone AI, how did you get it to work with the Kiwi ? have to admit I haven't been following the forum in a while.

It seems to get hot though, might not work well in my shed when the weather is warm.

Try get the EFHW with 49:1 working, works great for me, mine is 40 meters long there abouts and needs to be high I suppose like any antenna.

I wouldn't be too pushed on getting 1:1 or Close SWR, Most radios will work well up to 2:1 SWR and perform just fine, you could have a 1.1:1 SWR and might not be able to get the antenna up high and it will perform poorly.

The highest swr on my myantennas.com EFHW-8010 is around 1.8:1 on the higher portion of 80m, so from around 3750 Khz.

Here's a good write up on the EFHW multi band antenna with 49:1 UNUN.

http://gnarc.org/wp-content/uploads/The-End-Fed-Half-Wave-Antenna.pdf

The Airspy HF+ is a great SDR and really quiet, especially when you use the DNR on SDR Sharp and this is how I listen via the 7300, I don't use the 7300 audio, I use headphones via the laptop. It's great having the large waterfall in the monitor. This is why I say, for best performance and noise reduction and NB the expert electronics SUN SDR 2 DX is the way to go, I saw a demo and it's class, the NB on it is amazing too.

Get a 2nd hand FT-891 and it will do all your portable work and will do 5 watts if you want to work QRP which is a lot of fun but can be frustrating at times and when time is limited I just want to setup and make contacts.

Alternatively, you could get the Elecraft KX3 and the amplifier and you will have a really high performance rig that you can take portable and it will do 15 watts with external battery, not sure if all the AA batteries allows full 15 watts, this is an expensive way to go. You can add a panadapter later too but personally I would go with the FT-891 2nd hand if you can, save a lot of money and save for a proper SDR for your base setup, you will be glad you did.

I was using the FT-891 last night just for listening to LW and MW, performance on LW is way down and it's not as sensitive on MW but enabling the preamp solves this, on Yaesu this means IPO needs to be off. IPO on means Preamp is off.

I was impressed anyway, first time I really listened to MW/SW on it last night, I controlled it via the FLDigi software connected to the little Chromebook I changed to Gallium os which is a lite OS for Chromebooks. It works great. With FLDigi I can set the bands easy, USB/LSB AM etc, save stations and name them. It's a lot easier to use it via the laptop.

I don't think I'd ever sell the FT-891 and it sounds so much better with headphones. But they have to be a high impedance to work without hiss. Plugging in amplified speaker doesn't work well due to hiss, so headphones are best.

Anyway, let me know how you got the new beaglebone working with the Kiwi, I might just upgrade one of them.

What does it offer over the old beaglebone Kiwi wise ? is it actually worth the upgrade ?

I just checked here, interesting. https://valentfx.com/vanilla/discussion/1743/kiwi-bbai-software-alpha-test-instructions

Popoutman

A lot of the update from BBB (Beablebone Black) to BBAI (Beaglebone AI) is almost plug and play. I did the update mostly for the curiosity value, and to get proper 5GHz wifi, as the location I am at in Zurich has lots of 2.4GHz interference and poor quality wifi in that range as a result.

Yep, there are heat issues with the BBAI, and I haven't yet gotten all of the bits together that I need to resolve them for me. My plan is to get header extenders to increase the space between the BBAI board and the Kiwi board, replace the undersized heatsink(s) currently on the BBAI, and have better fan airflow when mounting the two boards back into the aluminium enclosure. At the moment I have two 5v fans ducted into one side of the enclosure, but I'm still sitting at 24 degrees above ambient temp with the BBAI clocked at 1GHz.

As for getting it running, I firstly powered up the BBAI and did a full update to current of the Debian version installed as standard, and got it on the wifi network. Getting ethernet-over-usb working was a godsend, as that meant I could do the connection management without dropping my own connection to the device. The 'screen' utility is also very useful for keeping things running if a connection drops.

Once I was at current and on the network, I put the Kiwi cape back on and downloaded the Kiwi packages and followed the install guide as per John's instruction on the forum.

What's the difference? As I run 6-7 WSPR listeners, I was unable to play with DRM decoding on the BBB kiwi without dropping every other connection. With the BBAI version, I have no problem running DRM decoding at the same time as having the other 7 channels in use. Compiling the Kiwi updates takes about half the time compared to the BBB, though it's also now possible to cross compile the update on another linux/mac on the network without having to drop every current connection to do the compilation locally.

Is it worth it? Unless you've got a mechanical knack for getting custom cooling to work in that tight space, or you need the 14 audio channels possible with the BBAI, or you need the DRM decoding, it's an expensive curiosity at the moment. The AI cores are not utilised currently with the available plugins for the Kiwi, and the number of Kiwis with the BBAI is miniscule which doesn't help a priority for the development effort. It was worth it for my purposes, and I'll eventually get it properly packaged and cooled appropriately once post-Covid postal issues are resolved.

I'll probably get a third Kiwi and play with getting it working on a Raspberry Pi, also for curiosity purposes, but that might be a few months out.

Popoutman

Popoutman wrote: »

A lot of the update from BBB (Beablebone Black) to BBAI (Beaglebone AI) is almost plug and play. I did the update mostly for the curiosity value, and to get proper 5GHz wifi, as the location I am at in Zurich has lots of 2.4GHz interference and poor quality wifi in that range as a result.

Yep, there are heat issues with the BBAI, and I haven't yet gotten all of the bits together that I need to resolve them for me. My plan is to get header extenders to increase the space between the BBAI board and the Kiwi board, replace the undersized heatsink(s) currently on the BBAI, and have better fan airflow when mounting the two boards back into the aluminium enclosure. At the moment I have two 5v fans ducted into one side of the enclosure, but I'm still sitting at 24 degrees above ambient temp with the BBAI clocked at 1GHz.

As for getting it running, I firstly powered up the BBAI and did a full update to current of the Debian version installed as standard, and got it on the wifi network. Getting ethernet-over-usb working was a godsend, as that meant I could do the connection management without dropping my own connection to the device. The 'screen' utility is also very useful for keeping things running if a connection drops.

Once I was at current and on the network, I put the Kiwi cape back on and downloaded the Kiwi packages and followed the install guide as per John's instruction on the forum.

What's the difference? As I run 6-7 WSPR listeners, I was unable to play with DRM decoding on the BBB kiwi without dropping every other connection. With the BBAI version, I have no problem running DRM decoding at the same time as having the other 7 channels in use. Compiling the Kiwi updates takes about half the time compared to the BBB, though it's also now possible to cross compile the update on another linux/mac on the network without having to drop every current connection to do the compilation locally.

Is it worth it? Unless you've got a mechanical knack for getting custom cooling to work in that tight space, or you need the 14 audio channels possible with the BBAI, or you need the DRM decoding, it's an expensive curiosity at the moment. The AI cores are not utilised currently with the available plugins for the Kiwi, and the number of Kiwis with the BBAI is miniscule which doesn't help a priority for the development effort. It was worth it for my purposes, and I'll eventually get it properly packaged and cooled appropriately once post-Covid postal issues are resolved.

I'll probably get a third Kiwi and play with getting it working on a Raspberry Pi, also for curiosity purposes, but that might be a few months out.

Interesting stuff, I will check out the forum.

Can you get 14 channels with the waterfall ?

I'd probably leave it as is for a while to see where development goes. I'd like to see better audio quality to make use of the extra processing power and better noise reduction, obviously the implications would be increased bandwidth but on 4G+ the upload is actually pretty decent, the option at least, would be nice.

I spent enough on the Kiwis so might leave them earn their money another while, I'm sure I could sell them though but don't want to run in to bugs and risk them being offline. You'd be surprised how many emails I get when they go off line.

Popoutman

The 14 channel mode is without waterfall. It does allow those using them as WSPR receivers/decoders to have all of the available WSPR frequencies tunable on a Kiwi being used.
I've mine in the 8-channel mode, with 8 audio streams and 8 waterfalls.

Agreed that the noise reduction could be better implemented on the Kiwi, but I'm not sure how I would go about that programming task.
When I get a chance, I'll be taking a look at installing and configuring nginx on a kiwi to fully and properly encapsulate the html/javascript page that the Kiwi daemon serves, in properly certified https:// as that would be a useful thing for a few people, and John doesn't have the time to work on it himself.