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Dan,

I have been calling CQ on and off from 3:00PM CST and nothing. I am not hearing much on 40M. Will look for you later.

Denis, WB8SKP

Hi Brent,

First,I cannot comment on whatever an l-match is unless you an l-network to match the transmitter for 50 ohms. The usual configuration has the inductor in series and the tuning cap to ground at the output end. That configuration is low pass and is just what the doctor ordered. One of the other configurations is high pass and will not help.

Low pass type antenna tuners have been cited as reducing the harmonics to legal levels in the U.S. I am using such tuners here while I am also building low pass and maybe band pass filters to go in-line between the transmitter and everything else downstream.

If we twist all knobs full right and change resistors to try and get a couple more watts (of overdrive?) then nasty byproducts get much worse. HF Signals says the microbitx is a ten watt radio on 80 meters and the power out drops as we go up in frequency. That is how I treat mine.

As for the olde daze, the required specs were a lot more lax than now. I'm sure you must have heard about all the RFI and TVI caused by hams using those old rigs (even though they were new at the time). Your comments are comparing apples to bananas. To quote one of my grandfathers, "the only thing good about the good old days is they are gone".

Those undesired products are removed with some types of tuners. I think Allison delineated some of them including L-networks. She has provided a lot useful info here. Others are working on internal mods to improve the uBitx performance and I will probably add something to mine. Later. Anything worthwhile along that line is going to be major surgery. The box I made for mine may not have enough space for any daughter boards. Hint, hint.

Let me recommend the CEC software for your uBitx after you get it working. Search terms include "KD8CEC", the author of the software. I am not using all the features available with his software but it makes the uBitx much more user friendly and makes CW really usable. I made a simple mod to control the CW sidetone level. Without that your ears will bleed. I am living without AGC or S-meter. They are not needed by me but you may want them for yourself. Louder is S-more and weaker is S-less:)

If you add all the mods with available kits and include the larger, touch screen displays the overall cost is much less attractive. That does not matter to some of the uBitx owners. Some of bought to experiment and lean. Enjoy *your* radio.

73,

Bill KU8H

--
bark less - wag more

Adam,
The microphone is polarized.
The switch you had received is connected between PTT line and GND and not in series with the microphone.
The microphone is connected between GND and Mic input. On the microphone capsule you can see that one of the pads is connected to the aluminum shell. That pad goes to GND, the other pad to Mic input.?
When you press the switch you should hear the relays engage and see an increase in current consumption. When you speak the current consumption should increase.
Don't forget to have a dummy load or an antenna attached to the Ant connector.

73,
Ion

VA3NOI

I gave several calls.? I'll come back in about an hour and try again.??
Dan, W2DLC

I'm calling CQ right now on 7.277MHZ.? I don't hear anyone else.
Dan, W2DLC

Okay
Here is another idea. Full disclosure, I'm not an engineer, and many here are much more knowledgeable, experienced and have far better test equipment than me. I do understand the basic math of resistance , reactance, resonance, etc. I also realize this idea is not in keeping with modern, minimal knob technology. Feel free to educate, debunk, etc...I won't take offence.

Would it be possible to construct a simple, tunable bandpass filter, to go in series with the antenna, or between the driver and the final. QRP, so old air variable cap should work. Just throwing the idea out there...

Brent
VE3CUS

Hi, do you try with a administrative user, for me arduino ide works only with admin user.
73-remi f1mqj

On Thu, Aug 23, 2018 at 03:34 PM, Mike KK7ER wrote:

Perhaps a future schedule could include a CW/RTTY calling frequency so that Technician Class licensees can participate.

To everyone who keep proposing other modes or other bands or other times, etc.:

Please feel free to actually make concrete proposals. I merely took over the task of posting these?notices from someone else (don't even remember who). I only have a?BitX-40 and a 40 meter antenna, so no other bands are available to me. I'm not set up for RTTY (yet) and my CW skills have gone the way of the Dodo bird.

So, again, make a concrete proposal and see how much interest there is.
?
--
John - WA2FZW

With a bitx40 detuned to 2 watts, I rag chewed for about 30 minutes with G0EVY Dave on 40 meter SSB. I do admit, Dave's monster antenna was probably doing all the work.? QRP SSB DX? is very possible, but it probably won't happen every day.?

According to this guy an S unit should be 6 DB. However, I would believe your attenuator pads over any absolute S meter readings. Because you are using a series of attenuators, if the receiver input impedance is for some reason not 50 ohms, that should come out in the wash and not be a factor.



There are many people that know a lot more about the practical aspects of making these measurements than me, but it looks like your analysis is correct.?

Call me old fashioned, but I remember fixing spur issues in an older (well, state of the art then) Icom transceivers by soldering additional ground straps to the chassis from critical points on the PC boards. Yes, the days of metal chassis, formed on a metal brake, rather than plastic 3D printed cases. The question I have is, if there are layout problems on the uBITX (and inadequate ground plane through-hole vias has been cited)-- is your uBITX mounted on a metal chassis or just the bare board?

The theory being, if the ground impedance is higher than optimal across the uBITX for solidly passing the current flowing through the PA and ground side of the low pass filters, to a good solid common ground island, could mounting the uBITX to a double sided copper clad PC board or a metal case, with all four corners of the board solidly grounded to the chassis or PC board help reduce the harmonics?

After that I would try replacing the traces around the low pass filters that run too close to the other lines. And experiment with a few ground straps to see if any difference is made. Just a thought, what I'll be trying when I hack together an SA for my own use. But, you are way ahead of me in being able to do measurements, now. If improving the grounds do not show any improvement in the harmonics, then the current grounds are likely adequate.?

Tom, wb6b

I use mine on CW only and have had a few QSOs with E Coast US, but not easy to make using QRP into my home 44' wire antenna. Have only knowingly had contact with 1 other uBITx:?EI8FH on 40m.
73 Chris G3SQU

Thanks for the links, Joe.? Do you live in 4 land?

Think it's in the levels I'm in.? The receiver has gotten out of whack with the BFO cal as a result of my fiddling.? I'll get that back on the reservation and go from there.? The MFJ antenna analyzer serves as a pretty good signal generator for zero beating.? Easier than a BC station or WWV.

The receiver was really hot before I started with these menus.? I'm wondering if the case kit that we're using didn't connect the dash side of the key jack, which was the case with the headphones?? Seems like a maybe.? Might go have a look there next.
Taking the bottom off is a bit wiggly as it leaves everything floating, but that's the easiest way I can think of to get to the jack.

Fascinated by the spur issue, but for now, not at the top of my concerns.? I don't have the computer software for the radio, but that may be coming.

Eddie

Thanks for the info Jack. That is helpful. I put a Serial.print(result) right ahead of the return(result) statement. One click of the encoder spits out 3 numbers on the serial port. Of those 3 numbers the last one generally corresponds to the change in the display.?

When one click causes one digit change I usually see 1,2,1 on the serial stream. When one click causes the tuning to change by 2 I usually see 1,1,2 on the serial port. I need to do some more of this, put in some more Serial.print calls and study the code.?

Maybe a little timing change will clear this up. Otherwise, if someone has an encoder part number that provides consistent results I wouldn't mind ordering one or two of them.

Thanks for the report and reminds me to go plug my mic in today!? THIS is why I got my uBITX and your report reminds me of that.? Thanks again.

Rob de AG5OV

On Sun, 26 Aug 2018 08:53:06 -0700
"Eddie Esserman" <ee@...> wrote:

Hi Eddie, are you using the KD8CEC sketch?
The default sketch dosn't have those advanced
ADC settings.

If you are using the default sketch, and the resistors and
voltages are right, then you are stuck.
/g/BITX20/topic/ubitx_keyer/7491087?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,7491087
As the main man says, its all in the software.

If you are using the CEC sketch:

I havn't done this personally myself, as I said I use
an external keyer for the paddle.
But........
You probably need to play with it a bit to get the hang
of how the tuner switch changes mode.
You probably need to be very careful recognizing which
mode you are in, and which sub setting you have on display.
Follow the above link. Sometimes you press the tuning key
and in some menus you need to rotate it to the desired
selection, then press again to change value.

Sorry, thats the best advice I have right now.
Good Luck, and be calm and deliberate with
your actions with the tuning switch.
Read the manual, there are 3 different pushes too.
A quick push, a longer push, and a 2 second push.
Each one will take you somewhere different. :-)

It says the Memory Manager has a setting
for the A6 ADC level. It's called the 'dot range'.

Joe
KN4OND






Joe

Thanks, Joe,

How do you (or I actually) get to the iambic a and b page?? That's where I think the block may be.
Straight key is working, and so is the dot side of the keyer. No dashes, paddle and resistor are good.

Eddie
WA4JXL

I've been doing a mix of CW and SSB since I got the AGC working and the side tone volume down to a usable level.? So far I'm mostly on 40 meters.
Dan, W2DLC

I do, much more than SSB. Even the BITX40 does a nice job. 73, Don

Charged the 7AH gel cell at somewhere around 250mA for about 6 hours and bingo, I can keep 11.8 volts? at a measured (cheap SWR meter measurement!) "5 W" output.??

With a CW signal at 3.510? MHz (LSB) I then worked sequentially through a series of additional attenuator pads to try and calibrate the ICOM 718 S Meter

FIRST -- I check for "bleed through" by searching with no connection at all to the ICOM718 reciever --- while I could hear the signal (not strong, but there) -- there was ZERO indication onthe SWR meter.? ?So I think there is little bleed through in my MEASUREMENT apparatus.

All measurements have approximately 50 dB contributed by the resistive divider I built into the BNC pickoff on theHeathkit Cantenna

PAD ATTENTUATOR? ? ? ? ? ? ? ?S Meter Reading
20 db? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? S9 + 25 dB
20 + 6 dB? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? S9 +? 20 dB
20 + 6 + 20 dB? ? ? ? ? ? ? ? ? ? ? ? S9? ? ? ? ? ? ?-- so the 20 and 25 db points on the scale above S9 seem reasonably relatively accurate
20 + 6 + 20 + 6? ? ? ? ? ? ? ? ? ? ? ?S 8 & 1/2
20 + 6 + 20 + 6 + 6? ? ? ? ? ? ? ? ?S 8? ? ? ? ? ? -- so the S unit between S8 and S9 is worth about 12 dB
20 + 6 + 20 + 6 + 6 + 6? ? ? ? ? ?S 7 & 1/2? ?-- continues the trend that an S unit is worth about 12 dB on this particular radio at? that frequency
=? 20 + (44 db)
Note that the last line is 20 +? 44 db -- roughly right at the FCC requirement if the fundamental is at S9+25 --- so if the fundamental is at S9+25, the goal is to get all spurious responses below S 7.5 on this meter.? ?

Within homebrew accuracy anyway.....

I think this is correct thinking....

Gordon Gibby


Gordon Gibby