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Allison, concerning the "stuff" coming out of the first mixer passing through the input lpf and reaching Q90: this gives me the hint that the lpf does not problerly do what it should! Did You make a

Henning, If you use Q90 you only need maybe 13-15db with headroom. I'll make a comment.? BANDPASS the output of Q90, there is way too much stuff coming out that can even if it meets -43dbc down

I gave phone/SSB a go last sunday from Northern Virginia, no luck. I have much better luck with PSK31 or JT8.? Does any uBITXer want to try digital modes on 10/15?? If so, I'd vote for staying on

Thanks, Allison. Jack, W8TEE

Allison, This is a plot with a 680nH inductor in series with one side of the coil and relay armature. Note the self resonance is now off to the right beyond the 100Mhz scan width and that the plot is

Allison, I totally agree,? my post was just thinking for the stage after Q90 or its better verison. My guess is that the BFR90 or as You already mentioned these small signal transitors are not good

timmy, Your not even close.? The Funster (a CW rig) topology is to drive a class C final for CW so linearity is not even considered.? So that is outside the conversation as usual. The drive needed

On Tue, Oct 9, 2018 at 07:54 AM, Henning Weddig wrote: oncerning the UBITX: the PA delivers 26 dB of gain, so for 10 W output the input power for the PA is +40 dBm - 26 dB = +14 dBm This power can be

STM32F4 series if memory serves. Allison

Thanks Gary! I had not thought to try mounting them on the bottom of the board so there would be a ground plane shield between the relay and other wiring. I just did that and ran the tests again.

Scott, Use the shortest leads possible, measure the inductance as quickly as you can after "Zeroing" your meter with the leads shorted. That's the way I do it. The inductance of the leads is a factor

Allison, It's 680uH which is the largest I found which will handle the relay current and has a self resonance around 2MHz. I tried 100nH and didn't see much difference. The 680nH parts have a self

On Thu, Oct 11, 2018 at 04:04 AM, Woody wrote: Already have new 680 uh inductors on order, not relays (yet). Don't you mean 680nh?? Its only a factor of 1000 difference between nH and uH. Allison

Hi Jim, or Raj, or …. I have trouble with reproducibility on lower numbers with my recently purchased LC200. Butt when I see people that know what they are doing having good results, I'm inclined to

Mike, You asked about the two LPF filters. Here they are pictures and plots. The components used on the small board and the large board are the same and they are both at about 10MHz (same filter

Amazon has the meter and accessories for $119.97. I’ll be picking up that meter off your recommendation. Joe

Wow wow. Okay no wonder I couldn’t hear myself too well on websdrs after the mod. I thought it was just band conditions. I’ll order those coils ASAP!! Thanks Raj for your knowledge as always Joe

... aha ... that is smart done from Ashar . Also the Raduino-Board now is mounted on the backside of the 25 MHz crystal board , not more inside between space of LCD-Board and 25 MHz board , that means

About the possession I guess that a non filtered output shows a higher power, which is the sum of the fundamental, the spurs, harmonics and all the garbage left.

I have my BITX40 up and running. Just got on the air for the first time a month ago. Lots of FT8 contacts and a few other digital contacts. I just put it in a case with a switch for the PA power