开云体育

The 8mhz clock is an RC oscillator inside the ATmega328, no external crystal or resonator required. Not very accurate, will wander about with temperature. But can be trimmed via flash bits if it winds

Mr Farhan did a great job of designing the uBITX and keeping the price as low as it is. I doubt it could be done, but I would like to see something along the same line that has NBFM and maybe AM and a

A good compromise might be to use external LPF's in the antenna coax when operating on seldom used bands such as 160m,30m,17m,12m. Recode setTXFilters() to use the the LPF for the next band up.? The

It has been discussed here before. I have a RPi3b running FLdigi and its ok with a external usb sound card and a FTDI RS232-3v3 serial cable. the serial cable provides DTR keying(externa or PTT)? for

Several things: The IRF510 is a very good RF device in that it achieves a lot of gain and at respectable power. That translates to about 16dB in the HF range with 50 -200ma of bias.? That also means

Too bad the pictures aren't clickable (for enlarging). Only the schematic gets bigger 73 K5KDT

Figured I would share my design of the front panel of the Banggood (

I find the Arduino clones easy enough, but the CH340 trips up lots of folks, especially those with a Mac. Doing away with or disabling the CH340, then coming in with a UART through D0,D1 allows a

Hi! I was discussing with Farhan on this topic for an add on demod board to add more versatility to uBitx.? CB radios often used a common chip for AM as well as NBFM receive. I enquired here and

Periodic message and note... The work I'm doing for the power chain is centered on getting about 10W and some level of uniformity to 10M.? Not all the things I'm doing will help if your goal is 13W

Increasing efficiency with frequency usually indicates not enough inductance or over coupling (too high a tranformation ratio).??I'd expect the efficiency to peak around 10mhz? and what finals are

Thanks for this.? I downloaded the code and will take a look.

FOKO The "Miguel" mod that you are talking about has become a de-facto standard for the QRP-Kits version of BITX.? It decreases higher frequency gain of the IRF510's and makes them less suceptible to

Yes! There's a wiki on doing a vanilla buid I started for the same reasons you mention.??/g/BITX20/wiki/uBITX-Assembly It's not mine, it's the groups, so feel free to improve it.?

Mornin' Joel: Agree 100%. The CAT people do need the interface and the reason I push that more than the non-USB versions is because much of my work is done with people who don't have much (any?)

I would like to chat with someone that has set there ubtx up with a raspberry pi and is using fl digi, I think this may be a good way to go as I have most of the parts. Not sure if I need an external

Oh, I forgot to add that we can make the ATmega328 even easier by eliminating the 16Mhz crystal and the two 22pf caps, and use the internal 8Mhz clock which runs a si5351 and OLED display just fine

Dave, Solder a wire to the 2822 audio chip 12v in PIN 2 and monitor the voltage when this audio dropout happens. A plated through hole may not be conducting properly if the voltage is dropping! OTOH,

Jack, You are so right about the clones. My first was a authentic Arduino UNO that I bought from Radio Shack for 30 bucks, (so I've paid the tax), now I have maybe 40 clones of all flavors including a

here's what I did... /g/BITX20/wiki/Digital-Setup -- www.bitxmap.com ( http://www.bitxmap.com )