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You using maple boot loader?
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Allen ?Merrell

Dual gate mosfets are still a way to go as preamp.? But we are talking a Bitx on two and
there are no others spots for them.

There are various amp modules most have drive requirements of 50mW or more so
you have to have that first.? that means two stages to get to that.? Also not all the
modules are linear they are class C like MHW710s I have a few of them, great for FM.

Allison

You must be an old fart like me.
Nowadays the 'pretty girls' are our grandkids. ?
I built an analog VFO in the 70's, doing all kinds of things to get freq stability with temp changes, etc.

My 2nd ubitx will have the touch display and mega2560 board that I like.

Doing good on FT8 and first CW contact today. The OM had the gall to give me 529! ?Never heard if lower than 449. ??. ?Had 3 watts on 20.
73, Bo W4GHV since '54

Farhan,

Sorry, I just realised it was the wrong post.

Here is the correct 45Mhz filter response (the scale was wrong on the first post):

/g/BITX20/message/45700

73, John (VK2ETA)

Hi Dr William,
How is your radio performing with the mpsh10 and rd16hff1 ?
73.

Let's assume you calibrated to a 1000 khz AM broadcast station.
And that you were 100 hz off in doing so.
Those errors are proportional to frequency, so the 12mhz BFO would be 1200 hz off, enough to flip sidebands.
If you can hear WWV at 10 or 15mhz, that's a much better bet for calibrating.
Or one of the shortwave broadcast stations.

The math is in?post? ??/g/BITX20/message/44515
For LSB mode,? ?OperatingFrequency =? vfo - (clk1+bfo)
If each of those three clocks are off by 100ppm, then by the distributive property of algebra,
the displayed operating frequency is also off by 100ppm.

?

My 3904s were gone long ago in favor of MPSH10s save the predriver which i not settled on yet. ?That stage has to be about 12 db to drive the PA (RD16HHF1s not those silly motor switches). About 28 dBm needed (and id like it to be more like 30 dBm so it can be freq compensated/ flattened if needed).

I did but I might have done it wrong...Is there a better way then just listening to the audio of an AM broadcast station?

Is the rig calibrated?
If frequency calibration is off by 100ppm, that can put the BFO on the other side of the 12mhz crystal filter.

I fired up the uBitx and connected it to an antenna and noticed that the stations are on the wrong sideband.

On 20 mts stations are only audible when I listen in LSB while this should be USB. I confirmed this with an other tranceiver that the stations I was listening to were indeed transmitting on the "correct sideband"

What to do?

I don't have to configure any jumpers to program my Pills. It works just like programming the Nano. No need to access anything on the board. Just press the Arduino compile/upload button and you're off to the races

Joe

You are correct, the CB ?is 128k ?and the C8 is 64k. All my pills are C8's ?but I have compiled some simple programs ?on them and told the arduino it was 128k ?version and they worked fine but the programs were not very big I don't ?know what would have happened if they would have been 128k ?they might have run or possibly crashed, lol, but I will use them anyway. I drug the mini out today and will play with it some. The pill is cheaper and easier to find so I will be putting ?the most time into it. I was thinking of connecting a 3 position ?toggle ?switch to the Boot 0 jumper on the pill and placing it on the back of the case where I could flip it when programming ?to avoid having to go into the rig and move the jumper to program. This would be in the final build and enclosure.?
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Allen ?Merrell

Agreed on the redesign effort.? I am used to working with 2M SSB (Sunday morning SWOT net), and have the 2M add-on to my KX3.? It works extremely well for satellites, as well.? With just the little Arrow dual-band beam I get S9 signals.? I am working on a design for a low-cost AZ-EL rotor for it.? The hard part, of course, is the az-el mechanism itself.? Since I want to minimize physically loading on the azimuth rotor, I think I will end up with a geared drive (1:1).? The elevation rotor would be a balanced load for the actual antenna by using a 2.2 lb offset opposite the antenna.

As for the 2M SSB design, has anyone thought about using dual-gate MOSFETS?? They can be quite easy to drive and VHF/UHF devices are not extremely expensive.? You can also get modules that provide 3W output at 450MHz for about $20, and pre-amps with 30dB gain for a bit less.? After Field Day, I will start getting serious about this, hi hi.
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Ron W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320
Editor OVARC newsletter

I have several Pills and the compiler reports all are 128K. The official 128K chip version is CB (I think), which looks very much lIke C8 unless you use a magnifier

Let? me know how you're making out using your Maple boards in Arduino.

Joe.

When the boards are delivered and tested, I'll put the design files and Gerbers on GitHub. I'll also make the boards available to buy directly from the fabricator.

Joe

Is there any interest in custom printed panels for the? ?? l added a fan to mine and printed a new back panel yesterday.? Which got me thinking others may want something similar.? Either like mine or changed for your specific build.

I posted about my first set here /g/BITX20/message/49117.? The front and back look the same it is just the lighting that is different.? I haven't given any thought to a fair price.? I would want to cover my cost and maybe have enough left over for a beer.? I print these with a .1mm thick brim so there is some flash/web to remove.? Fresh off the printer vs cleaned and ready to install would have some impact on the cost too.? Design time aside, these take about 3 hours each to print.? I can fit two on the print bed but it just doubles the time.? I print with the bed fairly hot which improves the finish but it also takes a frustratingly long time for the prints to be cool enough to remove without warping.? The face is smooth and glossy.? If you look very close there are faint lines from the printer bed and you might get a very small pit or dust inclusion.? I think they look great I just want give a fair description and manage expectations.? The inside is matte so it shows the printer lines more.? I print face down to get a good finish so the front has to be flat.? If you wanted something with protrusions I can do it but it will be matte and look like it came off a 3d printer.? I am currently only printing in PLA so these could get soft if you left them in your vehicle in the summer and it got really hot out.? For those of you that want to print your own I did upload blank panel stl files to the file section a while ago.? For the time being I will only mail to US addresses.? If you are interested please contact me off list or on list if you think your question or comment would be useful to everyone.

Doug
AC9RZ