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Hello! Is there a geramn bitx group somewhere? 73, Stephan DC8LZ QTH JN37XX

Jim, A two-tone test on an oscilloscope requires a subjective assessment of the shape of the resultant waveform in order to determine if you are generating splatter. It is *very* difficult to tell if

Thank you! I was just looking at your web page yesterday and wondering about getting the sources.? Ralph

While waiting for my filters to arrive from eBay I decided see what effect would result from replacing R27 with a variable attenuator. I attached two short lengths of miniature coax, one the each end

Both filter are identical as I cannibalized one from another uBitv3 for now. In my case the reduced power is slight on 80/40/15/10 but for some reason 20 dropped. Something on 20 is behaving odd, when

I found a Chinese supplier 45MHz filter supplier here https://www.alibaba.com/product-detail/45MHz-2-Pole-UM-1-Bandpass_60676734055.html?spm=a2700.7724857.normalList.2.4c2b75e8OZx7MS I'll try and

Yes Fabian with 'finals' I mean the power amplifier transistors, the IRF510. My UBitx had the heatsinks just put on the back of IRF510. If I had used a metal case in place of the heatsink I could not

and in addition duen to the mismatch of the filter (it is high iompedance so acts as an attenuator). BUT: if this is true then the drive Level to the mixer is also reduced thereby redusing the mixer

Link to ebay.ca for any VE hams wanting the filters

Hi, I am really pleased to see the 45 MHz crystal filter solution to the spur problems. I am writing up a MicroBitX article for our club - Michigan QRP Club - and this is a welcome last minute edit of

Hi Glenn It is not difficult to program a second (or third etc) firmware-emulated I2C port on the microcontroller. The inbuilt I2C/TWI peripheral isn't the only way to do it. I have code examples in

If he does not have? an RF powr meter he can put in a 10 W 50 R non inductive load and add a a two diode RF probe and measure the peak DC on a DVM. There are? passive? RF probe designs all over the

hi, cool to see you again here in post, can we make a call in german "relay station"? when you have echolink, you can call the "thüringen link-node" and we can speak over this, that was really nice

I forgot the caveat! Your transmit power comes down due to loss of the filter. Raj

Congratulations to Allison and the rest for all their trouble shooting and discoveries. Regards

He'll everyone i have problem with s meter i try to do it more than one time and it's doesn't work i followed the steps LM385? and LM386 can i find some s meter ready to use ? I need something that

Ray, that has to be the best shielded homebrew rx I think I've ever seen!? And SMAs everywhere. I bet there isn't a sniff of RF anywhere within a mile of your receiver.? ?Congratulations!

Changed the bias on the PA drivers ...Q90 - R 81 changed to 2700 ohms Q911,912 - R85 changed to 220 ohms, R 86 changed to 2200 0hms Q 92,93 - R 90 changed to 220 ohms, R 92 changed to 2200 0hms Q

The real killer with trying to use a 45mhz crystal is that it will almost certainly be an overtone crystal.? And I believe it would not be suitable as a filter at other than it's fundamental