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February 17, 2024. The Data Tells You Much.

Yesterday's posting was the lowest viewed blog posting all year. So, that tells me much about my blog reading audience. What I thought may be technically cool, in this instance fell way short of the mark. So, I will not bore you any further with the project: SDR Without A Computer. But long ago I learned even negative information is good information. 

One of my published projects, in SPRAT, the MC1496 Direct Conversion Receiver has the distinction of having received the most requests for the Arduino Code (nearing 200). That is telling in that the technical level of the projects has to be within the grasp of many hams who are not EE's or come from a technical background. 

I must remind myself that this is just a hobby. So, I guess my sharing has to be in the realm of simple projects, LC VFO's, plug and play kits with circuit boards and detailed parts lists complete with BOM's. Got it.

While at the Board and Care Home with the XYL, we have been watching a lot of TV. Netflix has a series called Extreme Home Makeover with Ty Pennington. Aside from the very sad stories that end in a better way, the building of a complete home in one week is astounding. It can be done, but there is much behind the scenes pre-fabrication and the all-important critical path job sequencing. (Yes, I did that for a living at one time.)

But from that TV show plus a tour through my extensive junk box, shelf of shame and projects that sort of worked, kind of worked or never worked sprang the kernel for today's blog post.

Below is my previous attempt to build a 4X6 single board SSB Transceiver Kernel. We have the RX/TX Mixer (TUF-1), the IF stage with 2 DGM's, the Balanced Modulator/Product Detector using the ADE-1, the Mic Amp (NE5534) and an Audio Amp (2N3904 & LM386). The Filter matching transformers are missing a sign of parts cannibalization. 



There must have been an OLED display in the build as I note the use of a 2N3904 power supply conditioner feeding the LM 386 audio amp. (Top Center of the Board -- three parts and it cleans up noise on the rail.) 

Also of note, the use of diode steering on the DGM's for bidirectional operation. That was an earlier post on this blog. There is also a fixed 8VDC bias supplied to Gate 2 on the DGM's and two small Green LED's that change brightness with signal peaks. This diode steering circuit is from G4GXO.

There is a relay that likely is a part of the TR circuitry. I even spotted a 2-pin header that was once used to unbalance an SBL-1 that was installed before the ADE-1 was retrofitted into the board. I have no recollection as to why this board is in the state that now exists. The filter is missing and that perhaps is a sign of a repurposing, or possibly suffered from the dreaded Dishal Diarrhea.

Of note: No Bitx circuits, No EMRFD, No TIA and No Facebook Groups influence. Not shown is the Band Pass Filter, Rx RF amplifier/Pre-Driver, the Driver and Final Amplifier Stage with LPF or the Digital LO/BFO (possible Seeed Xiao RP2040). Funny how these have all been covered in posts this year.

So, our goal is to Make Over this derelict and forlorn SSB Transceiver Board.  Hopefully this may have more appeal than yesterday's posting. Yes, for those who are Digital LO adverse this will work with a LC VFO, homebrew filter (which was on the board originally) and a well shielded external Crystal BFO.

This may have more appeal to you the blog readers, as you follow along versus the earlier posting SDR.

73's
Pete N6QW

PS. I did receive one piece of feedback from the Valentines Day posting about the guy who gave his wife an oil change in lieu of candies for that special day. I am only sharing what he said as a follow on to the oil change. "It will be a long time before he gets her in to the rack for any routine preventive maintenance!" I don't write these -- just sharing.

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