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Thanks, Evan,
I do have two dummy loads, the larger of which can handle up to 150W.? So I'll plan to build either the Salas or Hayward 40dB pickoff and follow it with a step attenuator.

Eric

Further info: The QMX, like the QDX power, will change with the impedance.? I have noted an increase in power ratings for SWRs that, when I put it on a dummy load, are 1.5 watts or more lower.? This could happen while you are adjusting for the LED dip.

73
Evan
AC9TU

Try using 12v rather than 13.6v. ?They are not the same for QMX purposes.

Hi Chuck,

Sorry to read of your problem.??

I believe that the QMX has an SWR function that is at reduced power.? It might be better to use it to adjust the Z-Match.? That would give you an easier-to-read number rather than an LED intensity.

Just a suggestion/
73
Evan
AC9TU

Hi Eric,

For best results, keep the input at the TinySA under -25DBm.? That means for 5 watts, a total of 36-(-25) = 61 DB.? An additional power attenuator of either 20 or 30 DB would be a good addition.? Get one rated for the highest power that you will be measuring.? If you intend to measure 100-watt QRO rigs, use a 40-db attenuator.


A Tap would be a lower-cost choice if you already have a 100-watt dummy load.? Here are directions on how to build one:


I built a slightly different tap from a no longer available webpage.? I have attached the PDF that I got from the site.

73
Evan
AC9TU

Thanks. ? I am getting a QRP Kits 41dB step attenuator, recommended in this forum.? What isn't clear to me, from the tinySA Ultra specifications, is whether its "recommended input power below -25dBm" is before or after the SA's built-in attenuator.? How do you read it?

Eric

I've used variations pretty much the same Z-Match tuner for many years.
Since the first NorCal BLT

Wasn't trying to get more power, just reducing the reflected RF for better SWR.
Supply voltage was 13.6 and band was 20 m.?

I don't recall exactly what happened the first time. But it was when I switched from
Adjust to Operate.? One suggestion was to reduce power and don't hot-switch.
I don't think I hot-switched. Another suggestion was an inductive spike.
Anyway, sent it off, got it fixed, and the same thing happened again. This time
supply voltage at 9, 30m, and I know I didn't hot switch. Also adjusted for noise
peak first.



I've used this tuner with everything from Rock-Mites to a uSDX+ with no problems. uSDX finals are
similar to the QMX, I think.? Used the same setup with the uSDX right after and no problem.?

Clueless in the suburbs of Point and Emory, Rains Co., Texas? EM22cv.


Chuck, W5USJ
EM22cv, Rains Co., Texas

Thank you to everyone who replied,

it took some time to follow up on the links and suggestions. It
would have suited me well to have found a good compromise keyer kit
with enclosure, a real time saver, something basic but with a
potentiometer speed adjustment. Fortunately, I think I have parts on
hand to build a version of the K3NG, I'd like one with sidetone output
to use as a practice oscillator for the bug and straight key. I'm a
SKCC member from years ago, but in need of practice before going on air
to torture other CW ops :-)

Ron VE8RT VE8TEA

On Fri, 01 Mar 2024 05:32:21 -0800
"Graham, VE3GTC" <colonelkrypton@...> wrote:

Ron,

I think you are referring to the old Curtis Electro Devices 8043/8044 morse keyer chip ???If so, I have no idea where you might get one these days.



As good a device as it was, there are better ways to get there today.

It seems that W3PM has an Arduino sketch program for a W1EL Winkeyer Arduino clone. I don't know any more about it other than what I find on this web page:



Digikey is the way to go. Orders to a Canadian address of more than $100 CDN ship free ( Purolator or Fedex, can't remember which ), under $100 a flat fee of less than $10. I can order early on Monday and often have my package on Tuesday. All customs are taken care of and shipped from Winnipeg. Plus they have nearly anything and everything you might want - products from Sparkfun, Adafruti, Raspberry Pi, and so on;? I wouldn't surprise me on day to find QRP Labs stuff too ;)

Digikey - PayPal - inexpensive flat fee shipping or free - delivery to your day by courier and I suspect that is even true in Yellowknife and you know you are getting good prime parts and products.? As good as Amazon, maybe even better in some respects.

cheers, Graham ve3gtc ( near Ottawa )

--
Ron VE8RT <ve8rt@...>

It bummed me out too!!!
--
Bill Harbour
K4VIB

Ron,

I think you are referring to the old Curtis Electro Devices 8043/8044 morse keyer chip ???If so, I have no idea where you might get one these days.



As good a device as it was, there are better ways to get there today.?

It seems that W3PM has an Arduino sketch program for a W1EL Winkeyer Arduino clone. I don't know any more about it other than what I find on this web page:



Digikey is the way to go. Orders to a Canadian address of more than $100 CDN ship free ( Purolator or Fedex, can't remember which ), under $100 a flat fee of less than $10. I can order early on Monday and often have my package on Tuesday. All customs are taken care of and shipped from Winnipeg. Plus they have nearly anything and everything you might want - products from Sparkfun, Adafruti, Raspberry Pi, and so on;? I wouldn't surprise me on day to find QRP Labs stuff too ;)

Digikey - PayPal - inexpensive flat fee shipping or free - delivery to your day by courier and I suspect that is even true in Yellowknife and you know you are getting good prime parts and products.? As good as Amazon, maybe even better in some respects.

cheers, Graham ve3gtc ( near Ottawa )

Well, no, that was someone else's suggestion...which means it's probably right. I don't know my butt from my elbow on the circuitry, I just followed the instructions on assembling. Good luck sir!

Good luck Bill! Let us know how it goes, please. I've been putting out 3.5w on 20m and 5.5w everywhere else for 5 months or so of regular operation, so seeing 0.2w really bummed me out ?.?

I think we have different root issues, Giuseppe...I do still have RF coming out, it's just a tiny fraction of what it was.

If you're running a windows OS, go to Start button, Run Program, and type 'putty', then hit run. It should have Putty already on your computer.? Then when it pulls up the window to determine which port you want to access, select 'Serial' then type COM* where * is the number for the comport your QMX registers when plugged into your computer.?

I'm not very good at explaining things, and I'm not a computer geek, sorry if this doesn't help.

My QMX is reading <.5w on all channels in the Putty diagnostic.? I have a QRP power meter that outputs to my DVM and that showed the QMX at almost 4w on 20m!? Below is the schematic for the QRP power meter.? My cheapo SWR/Power meter shows about the same.? It's a rainy day here in Mobile, AL and I'm gonna reflow all the toroids and transformers.




--
Bill Harbour
K4VIB

On Fri, Mar 1, 2024 at 05:49 AM, John Z wrote:

OK. How are you measuring output power? Can you measure current drawn from the power supply while transmitting?

?

On Fri, Mar 1, 2024, 5:18?AM mordan42 via <mordan42=[email protected]> wrote:

Receive looks okay. Waterfall was showing incoming FT8 signals. I'll check anyway, thanks!

?Yes, I can. I'll do that Sunday or Monday morning and post the results here (at work today, usher in a wedding tomorrow morning).

The diagnostics on Putty were showing 0.2 watts, and the Kenwood AT-230 was showing about a quarter watt. I know signal was getting out because this was first observed during a JS8 heartbeat signal which received acknowledgements from the Southeast and Midwest states, even with the tiny power...