Edit:? I was trying to use the wrong file.? I downloaded the zip files and everything worked fine.? ?The firmware is upgraded and modified for QRP.? ? An initial test shows the tuner does work, although not quite 100% of the time.? Will have to do some more checking when I get a chance.


Hi All,? I am new to this group, but not to the ATU-100.? ? A little over a year ago I built one of the ATU-100 (extended) tuners, but recently purchased a second one to modify for QRP use.? ?As several others have reported, the tuner came read protected, so when attempting to read the microcontroller all I get are zeroes.? ? I have been to GitHub and have seen all the files, but I don't know for sure which one to use for firmware version 3.2.? I have watched the videos on doing the QRP mod, and have read many messages, but have not seen anyone supply the file name I need to download.? ?I am assuming the file ends with a .hex extension.? ?On GitHub, I downloaded? ?atu_100_fw_EXT_32.hex, but when I tried to import it in the PICit3, it reported an error importing the hex file.? ?Is this the correct file to us, and if not, which file should I be looking for?? ?Also, I believe I read that you can just write the new firmware over the old, without having to erase first - is that correct?? ?I am new to this type of firmware upgrade (have done a little on a uBitx, but that's a little different) so any help would be appreciated.

Thanks,
Jim? (w8ykg)

Uups ... forgotten:
4) With reference to Glenns tip I measured voltages forward / reflected:
a) Power 5 W -> ~ 1.3 / 1.0 -> SWR 7.7 corresponding to displayed SWR
b) Power 2 W -> ~ 0.9 / 0.7 -> SWR 8.0 dito

<You should then be able to reverse the RF power in connection ...>
Not understood und thus not done ...

73 de wolf, dk1et

Hello together,

thanks very much for all contributions so far. Below my findings until now:
1) I reworked a suspicious soldering point and a possible shortcut, but this didn't fix the problem.
2) I tried to use Relay_Test and Manual_Test but failed because I don't understand the cryptic behaviour of the tests, how to use them and what they show as result. I asked David for a short description (/g/ATU100/topic/85305214). If someone has some explanation I would be grateful.
3) Following on from Scotts approach I'll try to get my money back via 'Buyer Protection' of PayPal. But it looks complicated ... dunno if it will work. I'm not very motivated to invest too much time in this ...

73 de wolf, dk1et
jo30ms

Hi David,

my ATU-10 doesn't work as it should, have a look at /g/ATU100/topic/89736113

Due to a hint in the thread I would like to test it more closely with Relay_Test / Manual_Test. I loaded the hex but I don't understand how to use the tests. Would be really great if you could provide a short description ...

73 de wolf
nr Bonn, Germany

hi,i designed atu-100.
www.atu-100.com

Ron
They probably vary a bit but mine needs a bit over 1W to tune.

Glenn

Will a stock ATU-10 work with QRPp rigs (1 Watt or less)? ?If so, what is the minimum Tx power that will allow an ATU-10 to tune?
Or is a modification required for use with transmitters that output less than 5 Watts Tx?

Thanks and 73,
Ron
n6ywu

tks, marius - just the info i was looking for!

73, bill

Chen from Hisonauto was a member of this group last year, dunno if he still is or if he left.

Vince - K8ZW.

--
Michigan VHF Corporation -- nobucks dot net
K8ZW -

Hi folks,

Brand new here and I am considering the purchase of an ATU-100 for my mobile.? I normally use a Kenwood TS-440 in the mobile and I am considering this tuner to go along with it since the 440 I have doesn't have the one built in.? However, after researching the ATU-100 yesterday, I am confused as to which one to purchase!? I see ones on eBay, for example, and it's hard (at least for me) to figure out whether I am getting the kit with or without the case.? The Chinese venders don't seem very clear about it.? I guess the baseline question here is: are there any good* kit versions available with case for $50 US or less? ?

I * good because that was something else I came across yesterday during my research.? I read about insufficient toroids and caps used in these units and would appreciate knowing whether or not this is correct.? The 440's maximum output is 100 watts on SSB, so the hope was to be able to run one of these units if a good, corrected one could be recommended.? I am on limited income, so I have to get this right the first time. ?

Thanks in advance,
Jon?

The Aliexpress seller tried desperately to get me to return the bad tuner at my expense before he would send me a new one. I refused (I told him I would send it back but he was going to have to pay for it), and when we reached a stalemate, I simply told him that I was going to dispute the charge with my credit card company and he can deal with them. That's when he decided to send me a new one. I now have two: one good and one bad. Your results may vary.

73
Scott
AK5SD

Once you have the picki3 it’s easy. You can adjust the horizontal and vertical too to get rid of the trash at the edges if there is any.?

m0nnq

I also use an mcHF. My ATU is a 100 with reduced turns on the transformer and adjusted config.?

I haven’t experienced the problem you describe but I can see how it would happen. ‘Proper’ transceivers with built in ATUs, such as my ftdx1200, are usually limited to 3:1 on the internal tuner. If you want to use a more marginal antenna you need to use a manual tuner.?

With a low power txcvr like the mcHF you’d be better avoiding such compromise antennas anyway.?

I don’t recall, but you may be able to configure the fallback power on the mcHF to be 1w.?

m0nnq

开云体育

Hi William,

I use ATU-10 with an mcHF; this transceiver also has 20W (and more) in 40m.

I noticed that at powers over 18 ... 20W the display shows "Overload" and the voltage on the ADC pin is over 4096mV. In order to be able to use the tuner with powers over 20W, I made the tandem at a ratio of 1: 6 and recompiled the firmware with the new value.?In this way the FWD voltage on the ADC pin does not exceed 4V, the maximum power applied (by tunning) would be somewhere around 30W, but it is at the limit supported (I think) by toroids.

Of course the deal will be made with a maximum of 15W as set by David.

Hi Scott & Beau,
thank you very much for your reply! I'll review your hints and report about results when done (which will take some time due to familiar duties with higher priority ...).
I used 'AliExpress dispute process' and seller acknowledged ... but then Hisonauto refused any further contact. Moreover, porto for returning the device would be very very high, and probably it will be 'lost in shipping' as I heard about in some other 'China shopping experience'.
73 de wolf, dk1et
from the banks of 'Father Rhine'

Wolf,

I agree with Scott that the problem is likely in the circuitry measuring the SWR.? I had a similar problem the a pre-built ATU-100 I ordered.? For me, it turned out it was a bad solder joint on one of the resistors that is part of the tandem match (the resistor was not sitting flat so it was suspicious).? A quick hit with the soldering iron and all was great from then on out.? Specifically, it was resistor R30: .? You may want to take a look at your board carefully and check all the elements in that path, e.g., whether the wires of the windings of the directional coupler, the resistors of the bridge (R14 through R18), and the other caps and diodes in that part of the circuit are well soldered (ATU-10 schematic here: ).? I hope you are able to solve your problem.

Sincerely,
Beau
KM4YMI

Hi, Paul
To use 100 W full power you have to wind 1:10 transformer. The ADC has a limit, it is impossible to meassure more than some maximum value.
But anyway, the tuner should to show "Overload" 5 times and stay working. If you have problems with "tighting" on high power, you have to look on the displays wires, good idea to make them as shorter as it is possible,
use ferrite cores and blocking capacitors.

I am experiencing an overload when using SSB on 40 meters.? Initially I used the ATU in CW mode without problem.? Last night I switched to LSB on 40m, and the 40-line display got corrupted or the ATU itself froze up.? After resetting the ATU and watching the display, I noticed that "Overload" appeared as the device crashed.? I am using a Yaesu?FT-891 which is 100 watts at full power.? I am basing comments on the 3.2 firmware and manual at?

When I built the ATU, I was not clear about the tandem-match transformer.? I wound it 7:1 which seemed to be the default required by the 3.2 firmware.? This is the first place I may have made an error.

I am looking for a way to debug this without reinventing more of the wheel than I must.? ? Any help will be greatly appreciated.

Thanks,
Paul KC3SHI

I had a very similar problem. My first ATU-10 would complete the tuning cycle but would not achieve an SWR anywhere near 1:1 (it tuned to 5:1 into 50 ohms). I managed to get the seller I bought mine from to replace it, but I had to go through the AliExpress dispute process. The second one that I received does seem to work, but the power reading that it reports is low, about 20-25%.

Back to your no tune problem. I have not had a chance to root cause the issue, but upon inspection of the inside I did note that a wire in the directional coupler was rubbing up against the ground lug screw on the back panel. The wire used is just thin enamel so if that wire has shorted out to ground it would throw off the tuning process. I would start there. I did look at the solder joints on the relays on mine and they seems OK, but the relay pins do not protrude all the way through the circuit board so there can always be a hidden cold solder joint there.

You can download some test firmware at the link below. There is a relay test that will cycle through all of the relays to make sure they are all functioning. If you suspect a bad relay or poorly soldered one, this will help you debug. Be aware that you need to connect the device to your computer using a USB-A to USB-C cable. The computer side needs to be USB-A. If you only have a USB-C to USB-C cable, and USB_C to USB-A adapter should work.


I've read some speculation that some of the relays may have bad contacts. However, I don't know anyone that has confirmed this.

I hope this helps. Try the?AliExpress dispute process if you haven't already.

73,
Scott
AK5SD

really enjoy my atu-10, and it has been great operating /p with my qrp rigs...

here's my question: what is the realistic max rf output through the tuner? 30W SSB? 15W SSB? or is the listed 10W the max at constant carrier?

tia for any info!