Thursday 13 April 2023

FLEXRADIO 6300 Signature


I've already had a Flex-1500 and a Flex-3000, so I'm not totally unfamiliar with them. Needless to say, the old Flex radios ran PowerSDR and the 6000 Signature Series run the latest version of SmartSDR, so there's new stuff to learn and enjoy.

The 6300 is part of the 6000 Signature Series and offers superb performance at a great price-point. This is not a standalone radio though - it will always need to be connected to a computer in order to operate it. Some view such things in a negative light, but in all fairness, every time I get a new radio, the very first thing I do is hook up an SDR receiver such as the RSPdx or the ColibriNano so that I can have a large scope and waterfall and control the radio from my PC, so having a computer-reliant radio is no big deal to me - it's actually a positive! Yes, we all like spinning a dial and pressing knobs and buttons, but I’ve got the wonderful RGO ONE for that.

The 6300 is a HF/6M 100W DDC SDR with some pretty awesome software and my radio runs the very latest V3.7.3 software. It can run two panadapters at once - the more expensive versions can run up to eight and they have preselectors which the 6300 doesn't. The sample I purchased included the £400 optional ATU ðŸ‘

Getting the 6300 up and running is a doddle - power, antenna, USB, PC and a network cable. Luckily I have a BT Router in the shack so it's easy to make a direct Ethernet connection. The radio takes about 30 seconds to load up and then you're ready to go. I'd say most people could just get straight into the SmartSDR V3.6.8 software - the basics are pretty intuitive. It's only the more advanced options which get you reaching for the manual.

Of course the performance of great software is dependent upon the performance of the connected computer and for a nice, fluid feel you need to have a decent computer - there's no use trying to get away with a shabby old PC you've had since the 80's, lol. I tried using my cheap Mini-PC and fully expected it to be okay, but it just kinda stuttered along.  Thankfully I have a powerhouse gaming PC (and a fast gaming-laptop that I could use if I wanted to go on a Field Day).

The slimline form factor of the Flex means that it’s easy to find a place for it in the shack - it’s just over a foot square (330x300x70mm). There’s just a single button on the front panel (On/Off) and three sockets for Mic (8-pin), Phones and Key (1/4”).

On the rear you have two antenna ports (SO-239), two USB, an Ethernet RJ-45 socket, Transverter BNC, Speaker socket (3.5mm), Accessory socket (15 pin), Anderson Power Poles and four RCA sockets for ALC, PTT, REM and TX.

The radio has small fans inside and although they're quiet, I would prefer them not to be on all the time. I've read that the PA fan can get quite noisy if you're transmitting at high power levels. Of course with this type of radio you don’t need to have it located right next to your seating position, so if the fans annoy you, you can always move the radio further away.

Rather than have a fist-mic laying around, I decided to use my PC’s desk mic. It’s a Fifine 669 USB mic on a small tripod. It works amazingly well for vocals and is an absolute steal!

With the Flex 6300 you can easily record your outgoing audio which makes setting up your TX audio a total breeze! The SmartSDR software has an 8-Band equaliser which allows you to tailor the frequency response to suit your voice and mic. You can save the settings as a named profiles such as “FiFine DX” or “Heil RagChew”, etc. If you find that your microphone doesn't produce enough 'oomph' you can give it a 20dB boost from one of the menus. You can also switch on or off the BIAS option to suit condenser and electret mics.

SmartSDR presents itself very well onscreen and whereas I usually want to change and customise everything, I was instantly happy with the look and the layout - it's fresh, clean, bright, informative and uncluttered. It looks good at many sizes and even when shrunken to accommodate other software, it remains fully usable.

I like how all the commonly accessed options are readily available, while the infrequently adjustable controls are tucked nicely away (but easy to get to). In particular, I love the way you move around the selected band. It's just so easy and intuitive to zoom into a section of the waterfall or to move from one end of the band to the other.  I'd say it's the best I've used to date - I really like it!

The maximum viewable width of the panadapter is 7MHz which is quite generous and way, way more than I'd ever use anyway. I rarely use more than 1MHz. The ratio between scope and waterfall is obviously adjustable and you can even scroll the waterfall backwards to see the history.

It's nice to be able to have two panadapters running at the same time of you want to monitor two bands and have two antennas connected. If you only have the one antenna, then you'd need to be using two bands which were harmonically related or you'd barely see any signals on one of the scopes.

Each panadapter carries its own control panel to the sides, so you have quick access to everything including all the adjustments of the filters. You can also chose which one will be the TX.

A handy little feature of the 6300 is the ability to record the incoming signals and play them back instantly over the air! This is great when you're chatting with someone who is testing a new mic or processor and wants to hear how they are being received at your end. Nifty!

The 6300's filtering is superb and so too is the DSP. In my shack I get some very annoying pulses and hash at various times of the day/night. I've never been able to track it down and it's only made bearable by good noise reduction - thankfully, SmartSDR provides that in buckets. 

Only yesterday, I was tuned into a weak Brazilian station (PP2CC) and it was right where I have local noise - I switched on the WideNoiseBlanker and boom, the noise was completely gone without any effect on the signal. I got the 5,500 miles contact logged and confirmed thanks to the Flex!  Adjusting the TX profile and switching the PROC to DX+ also made a huge contribution to the success of this 10W QSO💚

Don't get me wrong - these contacts rarely happen and you just have to be in the right place at the right time and have all your ducks lined up. But that's the thrill of it all!! I know people with huge linears who can make these contacts all day long - but that is kinda boring to me. Well, each to their own.

If you have a particularly annoying signal, you can use the SmartSDR Tracking Notch Filter to block it. You simply insert the filter wherever the problem is and choose its depth and width. That filter will then notch out the unwanted signal even if you open a second receive-slice. You'll be able to see the notch filter onscreen (and also the unwanted signal behind it).

On traditional radios I like to use the RF Gain to maximise readability of weak signals and in the main, I end up turning it down to improve the situation rather than turn it up. I find that decreasing gain decreases all the noise and allows me to better detect what the operator is saying. 

On SDR machines, it's a little different and I find that I can achieve great results by adjusting the RF Preamp and the AGC. Adjusting the AGC Threshold in particular, can make a huge difference. If the threshold is set too low, you can be inadvertently amplifying the noise! It takes time and practise to get familiar with making these adjustments on the fly, but it's worth it if you want to pull in that distant signal and be able to read it properly.

The SSDR RTX Equaliser also makes a worthwhile contribution to cleaning up the audio on the Flex. Having a set of sliders onscreen makes it real easy to make alterations and hear the difference immediately.

From an operational point of view, I am more than happy to make all the necessary adjustments using a Logitech Master  mouse, but when it comes to transmitting, I don't find it convenient to have to click the onscreen PTT button and then click it again to stop transmitting. This is because I might have moved my mouse-pointer during the QSO.  

To alleviate this problem I'm going to try using a TechnoFix PTT button connected to the 6300's PTT connector on the back.

I originally bought this button for my Elecraft KX3 and it's been a really handy little accessory. It allows you to easily activate the mic and keeps your other hand free to use the mouse or write notes. It's small and easy to hold in your hand and you operate it intuitively without a second thought. Brilliant.

I later attached my Elgato StreamDeck to the radio and created a profile for it which included a PTT button. You can read about it HERE.

If you want to use DIGI modes, SmartSDR makes thing simple. Unlike the old PowerSDR, there's no need to pull in 3rd-party solutions such as Virtual Audio Cables, etc, it's just a case of using SmartDAX which makes the whole process much more simpler than stitching together external programs and making them all shake hands with one another.  It's a similar story for CAT control with Flex's SmartCAT.  There's a video below which helps explain it all...

Click HERE if video doesn't show

I also like the CWT feature where you can send pre-recorded CW messages using the Function keys on your keyboard or even send them LIVE by typing into a text-box while the radio transmits each character that you type. It's worth pointing out here (for those new to the radio) that when keying, you won't hear a sidetone unless you have headphones plugged in. Or you could do what I did and use a tiny speaker…

The software is very well supported by third-parties and there's a plethora of useful add-ons available. It'll be quite a while before you have explored all the various options on this great platform.

Okay so that leaves us with one of the biggest attractions of Flex ownership - REMOTE OPERATION. Being an ICOM owner, I am already familiar with radios that have built-in servers (7610 and 705) and the ability to operate remotely, but the Flex  system makes everything just so much easier than other radios. And I'm not just talking about LAN - I'm talking WAN too, so it's easy to operate your Flex from anywhere in the world! You can even share your radio with other operators!

With your laptop and a decent internet connection, you can run SmartSDR and operate your radio with ease. There's usually very little latency - certainly not on SSB. The ease with which you can connect remotely is just staggering. It just works!!

Even better (in my eyes) is the fabulous IOS version of SmartSDR by Marcus Roskosch. This is just a fantastic app and it is so good that it's lead to people selling their Flex Maestro!! I have an iPad Pro 11 M1 and I can confirm that the software runs magnificently on it and it looks oh so good. Everything is so fluid and the software includes some amazing tools/utilities.  
This is a big plus for most people, but for me in particular, it's a boon! My shack becomes unbearably hot in the summer which makes it a no-go zone. Being able to just pick up my iPad and sit somewhere more comfortable is fantastic. And being IOS software, you just know that it will work reliably and without any glitches.

The software costs around £65 which may seem a little expensive to some, but just consider how much a Maestro would cost you! Below is a video of how the Flex works on an iPhone or iPad.  It's not particularly well shot, but it's informative.

There’s a wide range of really useful tools included with the App and everything’s really well stitched together and functions without a fuss.


So, that’s about it for now. I’ve still got lots to explore and I’m enjoying every minute of it. I’d like to discuss the negatives, but I just can’t really find anything of any significance. In my opinion, the Flex 6300 is one of the few bargains available on the secondhand market today. It offers a lot for a little. And now that full remote operation will be permitted on a Foundation License, it's even more attractive.

Leave a comment below.

Many thanks and kind regards,

Tom, M7MCQ.






VE9KK said...

Good morning Tom, excellent review of the Flex 6300 radio. I have always wanted to take the dive into flex. The 6300 has been my choice if I was to take the dive. Now that they have been out for a while the price on them used is not to bad. I have looked at the Flex rigs that are on the market now and WOW they are pricey.
Thanks for the run down and you have brought me a step closer to putting one in the shack!

MadDogMcQ said...

Hey Mike, hope you're well.

Yes the 6300 is offering the biggest bang for the buck right now. Although used prices aren't too bad, I would suggest saving searches on eBay, MarketPlace, etc and just putting cheeky bids in. Most times you'll get ignored, but sooner or later someone always accepts your offer. It's worked for me many times and I've got some amazing bargains.

73, Tom, M7MCQ.

Chris said...

Good write up. Not used mine since I got the SunSDR Pro2. Still a keeper though.

MadDogMcQ said...

Hi Chris, thanks for visiting the blog and leaving a comment - it's appreciated!

To be honest with you, I saved two searches on all the big selling platforms - one for the Flex 6300 and one for the SunSDR Pro-2. The Flex appeared first.

I LOVE that SW2 (and 3) software and use it regularly with my Colibri Nano. I used to have the big MB1 transceiver but it developed a fault and I ended up sending it back for refund.

At some point in the future I'll probably have a Pro-2 in the shack

Thanks again.

73, Tom, M7MCQ.