This 
Have a bunch of RP2040 and RP2350 boards, as well as the excellent free C tools, micro Python works well for simpler tasks and you can knock up an embedded Python app in a very short time.
Plus living in Cambridge I can visit the Raspberry Pi shop and buy any of the boards over the counter 
(there has to be some compensation for no hills…), and everyone round here knows someone who works at Raspberry Pi, they are a great bunch of folk.
ATU-10 arrived to today. I bought it from Amazon rather than AliExpress so I could moan at Amazon if it was rubbish. As it is it would appear to be very well made, no glue or crufty assembly. Came with an Allen key for the case and a USB-C charge lead. All seems to work from some simple tests but I’ll try it tomorrow. Best of all I had a large Amazon voucher I’d been given as a thank you and so this had no obvious cost to my wallet.
Reports to follow.
It will work, its a nice tuner for portable antennas. Sometimes it even works in 50 MHz. Depending the antenna you are using.
73 Jorge.
It worked perfectly today with my 705.
Ich habe meinen seit ca 12 Monaten in Betrieb bei ca 30 Sota Aktivierungen. Bis dato kann ich sagen dass der Tuner sehr sehr gut funktioniert. Ich hatte noch kein einziges Problem damit. Note 1
73 Armin DF1AI
There are many companies building ATU-100 and ATU-10 tuners as the software and hardware design is open source. Some are better than others. As I wrote I bought a very cheap ATU-100 and had to spend some time fixing the horrible way it was put together.
I tried my new ATU-10 with my 705 on Burnhope Seat G/NP-003 connected to my 20/30/40m trapped EFHW using a 1:64 match. The ATU-10 tuned up effortlessly on 15m, 17m, 20m and 40m in a very short time, probably a second or two and if the display is believable, the SWR was always less than 1.2:1 which is fine. You can integrate it with the 705 so the radio controls it as you operate but I just pressed and held the tune button till it said “TUNE” on the front panel and sent a carrier and brrrrrrrrrrrp, it would tune. So I’m very happy with the performance and build quality of mine. The only downside is the display is not too bright in sunlight, I needed to shade it with my hand. That may be a good reason to use the 705 integration.
There were a range of vendors selling on Amazon.co.uk with varying prices. The following should identify the company I bought mine from. However, there’s no guarantee every item they sell is as well made!
I don’t know if the tuning range is as good as an Elecraft T1 but a new T1 is about £256 plus VAT which is £308 plus shipping. My ATU-10 was £92 including shipping. It came from China and arrived when stated on the purchase. As I said, you can get them for less but I didn’t want another item filled with glue and the wrong components!
Based on my statistically valid sample of one unit bought and one activation made, I’d buy another from the same vendor 
Have you tried connecting to to the 705 with a 3.5mm cable ?
I guess any normal stereo aux cable woyld work?
I have done it with the ATU-10, works fine with a standard 3.5mm stereo cable.
Ah nice,good to know!
73 Karlo
It’s good this thread came back to life as it reminded me to add a thank you. I borrowed a Pickit 2 from a member of my radio club and got it working with PICkitminus. At this year’s Blackpool Rally, Ian G7ADF wandered up and gave me a PICkit 3. He said it had been in a drawer in a desk for years and he no idea if it worked or not. But it would be better if someone may use it rather than it just festering in a drawer. I tried it and it’s fully functional. So thank you Ian. It’s now sat on my PC along with a USB mini-A cable and a PIC ICSP cable.
An update on my now rather old ATU100 EXT model, that previously worked fine, now causes a constant “blip…blip… blip” noise on top of the received signals, so I suspect some component or components have aged and now are causing this issue. Apparently, these units are critical of good earthing and a dry solder joint from the pish quality construction (I bought mine built, not the kit) could be the reason.
73 Ed.
Mine does this Ed. It started when I removed the built in LiPo and charger and power the ATU from the same battery that powers the PA. (My setup is KX2 or IC705 + ATU-100&MX50 PA combo).
I just haven’t got round to improving the ATU-100 PSU decoupling. I’m assuming the CPU in the ATU-100 sleeps for a few seconds then wakes to see if it needs to do an auto retune. The noise is the CPU waking and running code then sleeping.
Maybe turning auto tune off and always using the tune button would make it go away?
Thanks for the tips, Andy. My ATU is set to manual, as the auto-tune doesn’t seem to work reliably.
I have just resoldered all of the connections - no change, still blip, blip, blip across all bands.
This model has no internal LIPO, but interestingly, it has a floating power connector, so this may have been at a point when it was being considered but not fitted. It is powered from the same (12Ah LifePO) battery as the amplifier. I can certainly drop another battery in the case to power just the ATU-100 at least to test to see if that makes any difference.
Cheers Ed.
Well the fix is to find if the noise is radiated or conducted.
Run the ATU from its own battery and see if the noise is present. If not then it’s conducted and suppressing the 12V in should reduce it.
If it’s still present then it’s radiated noise and you will have to see where it comes from. My sneaking suspicion is it will be a regular nad periodic update of the OLED display… it’s I2C or SPI, can’t remember but that means there will be a serial burst of data when it is updated. In a perfect world the display would be updated only when the data changed. But people who write software will know sometimes it is SO much easier to send the same data over and over rather than write cleverer code.
Try pulling the cable to the OLED at the main PCB and see if that fixes it and you’ll know where to work.
Hi Andy,
Just sorting out to try a separate battery, I’ll let you know if the supply was the cause.
If the interference is still present, and considering this did not occur when I first got the ATU-100, I would expect some hardware component gone faulty rather than the programmers logic of screen refresh. Then we come to whether I want to take on a project to find the faulty component (which could be SMD) or whether I pay €35 for the current unit knowing it “should” work for a few years without this problem.
I think I paid around €100 for the one I have - at €35 for a replacment, its sad to say but it makes more sense to simply throw this one out and get a new one.
Lets hope it is the power lead, that I can fix.
73 Ed.
OK, here’s the update. To my surprise, running the ATU-100 off a separate battery (an Eremit 2 Ah LifePO4) the bip, bip, bip went away!
My guess is that this interference therefore is coming from the 12Ah LifePO4’s BMS electronics, even though, the transceiver, (in this test a Xiegu G106) is connected to the same battery and has no problems - so it does look like the power filtering in the radio is good enough to drop the interference but the ATU-100 isn’t.
73 Ed.
I don’t think so.
Well, the interference is there when the amplifier is not powered on, so there is only the 12Ah battery and the ATU-100 in circuit so I cannot think from where else the interference can be coming from.
From the ATU electronics.
But why when I use a separate battery is the interference no longer there?