Yesterday I received an email from Jim up in 7 land inquiring about some Arduino sketches and problems compiling the sketch. I think some of the code was provided by me. I too at times have noted some issues with sketches that previously complied "slick as anything" but then started to hiccup.
Has any one heard about Arduino code that may contain viruses?
Pete N6QW
SS Podcast #210 we talked about the Vintage Sideband Roundtable ~ at any minute smoke and flames can come from an old boat anchor. It is true!
Try this with your uBitx!
Pete N6QW
Just can't leave well enough alone! #4
Search this blog for the Simpleceiver and you can see the painful detail on how to build one. The other day I was thinking about the original Simpleceiver and how that I still had most of the prototype boards still screwed down to a chunk of wood. Frankly I was OK with the 12.096 MHz crystal filter but still felt it has some short comings. So then I thought about popping in a 9 MHz GQRP Club Filter in the IF stage and that caused me to revisit the IF amp design and what it takes to move it down to 9 MHz which is the filter Cf.
A bit of digression as it was on this very prototype board that I came up with the single pass relay switched amplifier approach. Essentially the signal passes in a single direction through the IF Amp Block and on receive the signals coming from the Mixer Stage (SBL-1) are passed through the IF amp Block on to an ADE-1 which is now the Product Detector. With two relays and a bit of coax on transmit the ADE-1 is now the Balanced Modulator and its output is relay switched to the input side of the IF Block Amplifier stage and the Output Side which is now SSB is relay switched to the SBL-1 which is now the transmit mixer stage. There is no switching of the LO and BFO --just relay steering of the signals through the IF Amp Block Stage to always pass in a single direction.
The 12.096 MHz IF Amp block had just a few changes to resonate the tank circuit to 9 MHz. The 5.13 uHy inductor is made with a T-68-2 (Red Core) and has 30 turns of #24 enamel wire. The 400 pF is a 180 and 220 caps in parallel. Following the 2dB pad is a 6T to 19T matching transformer on a FT-37-43 Core (#26 enamel) as this matches 50 Ohms to 500 Ohms which is the Filter Zin. On the output of the filter is a 9T to 19T matching transformer to match the Z out (500 Ohms) to the input which is 2.2K [9^2 = 81 and 19^2 = 361. 361 / 81 = 4.45. 2.2K/500 = 4.4. Close enough for government work. ]
I needed a bidirectional amp stage ahead of the Band Pass Filter with one half being the receive RF amp and the other half the Transmit Pre-Driver. I had a board I made that was designed for the AG30386G MMIC amp and so I used that approach. Just as easily I could have used another J310 stage with relays to do the same job but opted for the MMIC stage since I had the board and the devices. The transmit driver is the standard 2N3904/2N3866 from EMRFD and the final is the IRF510. The Mic amp and Audio Amp were already on the prototype board (2N3904 for the Mic Amp and the Audio Amp is the NE5534 and LM380). I have now switched over to a newer (and better) mic amp design which now gives a flat response from 250 Hertz to over 10 kHz.
The console to the left is to be replaced as it was just pressed into service to get the project "hot on the air". The replacement is shown in the third photo.
Yes a real kluge --but works --several QSO's so far including one running 600 watts! You have to love those GQRP Filters.
73's
Pete N6QW
A bit of digression as it was on this very prototype board that I came up with the single pass relay switched amplifier approach. Essentially the signal passes in a single direction through the IF Amp Block and on receive the signals coming from the Mixer Stage (SBL-1) are passed through the IF amp Block on to an ADE-1 which is now the Product Detector. With two relays and a bit of coax on transmit the ADE-1 is now the Balanced Modulator and its output is relay switched to the input side of the IF Block Amplifier stage and the Output Side which is now SSB is relay switched to the SBL-1 which is now the transmit mixer stage. There is no switching of the LO and BFO --just relay steering of the signals through the IF Amp Block Stage to always pass in a single direction.
The 12.096 MHz IF Amp block had just a few changes to resonate the tank circuit to 9 MHz. The 5.13 uHy inductor is made with a T-68-2 (Red Core) and has 30 turns of #24 enamel wire. The 400 pF is a 180 and 220 caps in parallel. Following the 2dB pad is a 6T to 19T matching transformer on a FT-37-43 Core (#26 enamel) as this matches 50 Ohms to 500 Ohms which is the Filter Zin. On the output of the filter is a 9T to 19T matching transformer to match the Z out (500 Ohms) to the input which is 2.2K [9^2 = 81 and 19^2 = 361. 361 / 81 = 4.45. 2.2K/500 = 4.4. Close enough for government work. ]
I needed a bidirectional amp stage ahead of the Band Pass Filter with one half being the receive RF amp and the other half the Transmit Pre-Driver. I had a board I made that was designed for the AG30386G MMIC amp and so I used that approach. Just as easily I could have used another J310 stage with relays to do the same job but opted for the MMIC stage since I had the board and the devices. The transmit driver is the standard 2N3904/2N3866 from EMRFD and the final is the IRF510. The Mic amp and Audio Amp were already on the prototype board (2N3904 for the Mic Amp and the Audio Amp is the NE5534 and LM380). I have now switched over to a newer (and better) mic amp design which now gives a flat response from 250 Hertz to over 10 kHz.
The console to the left is to be replaced as it was just pressed into service to get the project "hot on the air". The replacement is shown in the third photo.
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Yes a real kluge --but works --several QSO's so far including one running 600 watts! You have to love those GQRP Filters.
73's
Pete N6QW