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The Gram zip file have about 250Kb of size and I can?t upload now I will try later... 73 PY2OHH

Hello friends I am building another BITX40, my other with two bands work great but there are many external boxes to plug togheter... If you are looking articles for mesurenents of filtres by sound

Hi Julius, that is the fun, nothing to adjust in advance, just connect it (I used two resistors as a signal attunuator)and watch the screen (if you receive enough noise). If you do not receive

Hi! Elecraft has often published doc related to SSB filter alignment using Sectrogram: www.elecraft.com/Apps/new_fil_docs/k2_cw_gram.pdf Excellent page here not only provides the uncrippled

In German Funkamateur was published schematic for hf noise generator and described metod of mesurment by using sondcard lf spectogram. I am sorry that it is again in russian but can be easily

Allison That URL for the MOSFET HF Amp is actually: http://www.cnham.com/pdf/amp/irf510/HF_use_FET_1.pdf I wonder if anyone has ever tried a grounded-gate MOSFET linear...something much like

There are at least two or more designs using IRF510s in push pull form. The power out was in the 30-45 watt range for two devices running at 24V through 10M. This is reasonable for the class

With the software and connecting the output of the AF amp to PC, i wonder where do we set the BFO to find out the shape of our filter, assuming that we do not know the center frequency yet, or

Hi Chris, Thanks for your answer. As you can see in my reply to Allison I will follow your advices. With you I hope that more pictures of the filtershape will be dropped it in this group. The

Chris My BITX40 uses 24 volts on the IRF510 for a power output of 11 watts. It required the addition of separate sheilding, 2 ferrite beads on the gate lead, and a paracitic suppressor (2 ohm 2 watt

Hi Allison, Thank you for answering my questions. I understand that changing the amplifier stage is not a good idea: variabels are depending on each other and calculate the impedence is not easy.

Hi all, did anyone tried to put higher voltage on the IRF stage? If so, I am interrested about the results like: - stability, - increase of output power. If the output power is not much higher and

Indeed measuring is knowing if the final result is in line with the original expectations. As mentioned before, it can be easily done with the sound card. At that time, I asked for feedback

de 4N1ZM I was looking in different designs of ssb trx and it looks like that most important part is exactly filter. And that is place where successful work of trx can easy fail. Crystals are

favourable candidates for a 6 m PA. The 2SC Japanes transistors are more common and most likely much easier to use. A line up of 2n4124, 2sc1970 and a pair of 2sc1971 will do 9-11W CW power at 12V

The putput impedence is affected by both the load resistor and feedback resistor value. Mismatch under 1:2(2:1) is resonable for thos application.

Hi Ruud, as I remember, you asked for a solution in the circuit, by using other resistors. I kept the circuit 'original' and added very small transformers, pictures can be seen in the BITX17 Photos

Thanks for the good info dear Allison, Yes, in the meantime I discovered MOSFET IRF's are not most favourable candidates for a 6 m PA. The 2SC Japanes transistors are more common and most likely

Allison, & others... Since the time constant in an H&P (Huff and Puff) stabilizer is usually much longer than that of a traditional PLL, a PIC-based H&P design might be quite easy to implement. I

Within the base ladder filter topology there are subgoups of type. They can designed as minimum loss, butterworth, linear phase or Chebychev not unlike LC filters. Each has it's differences