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Raj, Thank-you for clearing that up for me.? I plan on making the modifications you recommend as soon as the parts come. Happy Holidays to you and yours. Evan AC9TU

12vdc from the battery, but after a resistor and the 7805 is 5vdc.

What is the supply voltage for the VOGAD board ?

Hi all, I have tested a mic compressor based on the VOGAD SL6270C (same schematics of its datasheet), and it works very well on the ILER QRPs. However when connected to the ubitx something weird

Evan, The caps are only DC blocking and do not have an effect on the filter. I mounted the coils where convenient. I scraped off the green pcb coating and soldered. You can also mount them exactly

Chris, There is code in the uBitx software, both from the original and KD8CEC code.? I found the following: //original code with modified by kd8cec ? if (usbCarrier > 12010000l || usbCarrier <

The LPF is designed (we hope) to match the 50 ohm impedance of the antenna...The output (L4/C204) needs to be matched to the input of T2 ...Optimally thats 50 ohms ..connecting your SG across it adds

You're welcomed;? My first run with this (lower output audio than happy with, sans shouting) involved the pre-amp that was built into Midland land mobile radios back in the 1980's.? Having worked

I will give that a try thanks. Nice idea you had on the potentiometer.? I did try something else.? Putting in 1900uv at the antenna gave .1v p-p? where 1900uv at tp1 only gave only about 33mv

Hi, all. At the risk of seeming OCD, my current firmware and Nextion 2.8" display goes maybe 80% across the screen, I'm sure that I am seeing all of the firmware "screen" that I should see, but it

For mike gain, add an AGC mike board to the mic circuit. Think of this as more along the lines of audio compression than as gain per se.? You will want to put a small elecrolytic cap between this

There ya go ....Transistor is good, elsewise changing the bias would do nothing ..likely the "hum" is being generated because the fool thing is actually amplifying ...Not gonna cost anything extra at

Do confirm all is okay from audio output back to the xtal filter output. At the input side of the xtal filter, proper bfo adjustment is essential so that the carrier falls into the narrow

With a potentiometer base Q70 to ground I could get 6 volts with it.? It picked up a hum though when I did that.. maybe due to the potentiometer and long alligator clip jumpers I was using.? So that

Hello everybody, I build the UBITX by scratch. The second IF is 11.979300 Mhz because of the crystals in the ladder filter. In Arduino I use the kd8cec software v1.1 with nextion display. In the

We've got a bunch of different spurs. For example, the 12mhz spur due to clk0 crosstalk into clk2 is not going to be cured by swapping out L5,L7. Also, I would not expect that swapping out L5,L7 would

No sweat ..Thats how I checked mine ..With that miserable "floating bias CR#P" on that circuit, the beta of the transistor determines the operating point ...varying beta will give varying static/no

Hmm I did find someone mention the Q70 collector on their board was the same 1.7.?? /g/BITX20/message/54390?p=,,,20,0,0,0::Created,,q70,20,2,20,20335948

Evan As I recall, the worst spurs are above 14 MHz. I would not let this keep you off the air, and if you use an antenna tuner it may provide some reduction.? of course it makes sense to remedy the

Thanks for taking the time to look into it.? I measured the transistors with no signal going through at all. Hmm.. So you are thinking that all the biasing/feedback resistors are all correct but the