N6QW -- Left Coast Radio

What a great day to Binge on Chocolate and experience the pain of that filling that has been leaking.  I would be in that category with the leaking filling(s) had I not just spent an amount equivalent to one of the fancy new uptown appliance box transceivers on two filling repairs. Well at least I can binge on the Chocolate bunnies without fear of pain. Regrettably everything appears to have jumped in price including the price of parts. Well not so much the parts as the shipping costs.  That notably is seen in the eBay treasures. I spotted a nice heathkit DX-20 for about $50 and the shipping was $65. Likely it is a twofer with part being a way to in effect charge a higher price by inflating the shipping and in part by increased shipping costs. Shipping with insurance across the US was about $150 for this jewel and that was three years ago. 6AM on the Left Coast ~ 20M Easter Sunday! My only hope is the cost of Chocolate Bunnies remains steady although a pound of See's Candies for th

 One of my cherished boat anchors! Since 1967 I have owned about eight SWAN SW-120's and this one I acquired about 14 years ago. For those who don't know, the very first offerings from Swan Engineering were three mono-band transceivers covering the 80, 40 and 20M Bands.    This particular unit appears different from many of the single band Swan units and that is because while not in the 1st group of 10 produced (Gold Face) it was in the early builds and built in Benson, AZ. The Swan Net has a keeper of the S/N's, and I was told this one was built in June of 1961.   Noticeable is that later units had a Meter Face over the dial readout and this one has a very expensive Triplet meter. The later units had a less expensive meter and the dial cover and the meter front matched. The final is a 6DQ5 and typically you can get 100 watts on Tune. The Balanced Modulator is a RCA 7360.    [AD4DQ on his QRZ page has photos of his vintage gear. Sitting side by side is a photo of two Swan u

 FT-8 with a RPi Zero W Given the FT-8 achievement maybe even QUISK   would work on the RPi Zero W for a really small SDR Transceiver. But all that glitters is not Gold! The Zero does not work well with Chromium and even Firefox is an issue. So, it is a bare bones device, and you trade off the low cost with low performance. But for FT-8 this will do just FB. 73's Pete N6QW

  If you dabble with homebrew then most likely at one time you have used a Dual Gate MOSFET (DGM) and Type 43 Ferrite Cores. Type 43 cores especially the FT 37-43 form the backbone of much of our homebrew gear. They show up as matching transformers or RF Chokes. The Type FT 82-43 can become a 2.5 Millihenry RF Choke with about 70 Turns of #28 enamel wire.  Amidon is a short distance from my QTH -- about 70 miles but a standard shipping fee of $14 for $12 worth of product is not cost effective. The W8DIZ Kits and Parts is of course a great alternative especially since he is known as the Toroid King.  But a funny thing showed up on my phone yesterday and that is that Digi-Key sells the Fair-Rite Toroid stock. Don't get too excited they only sell the ferrite side not powered iron. Below is a link to the equivalent FT-37-43 cores and 100 pieces are about 21 cents per unit.  The Al values are the same so whatever turns are specified in the design will work with these Fair-Rite cores. Th

I have boxes of boards that didn't quite make the grade and I now find since I have little time to build new, this is a perfect time to fix some of those boards. It is all there -- they just don't work. Here is a case of a candidate board where I tried to skate by with a 4-pole homebrew crystal filter and it had a few hiccups. This is a ripe selection.   A Board that might become a Rig. So, what really happens with a filter of less than 5 or 6 crystals. Ten Tec sold the early Triton I and II radios with 4 pole filters and early on KVG made a 5 pole and 8 pole 9MHz filters. [I can really tell my Triton II only has a four-pole filter. The Triton IV has an 8-pole filter.] The 1st problem is that the lesser pole filters likely have a shape factor such that the skirts are not approaching vertical but more like gently rolling hills.    A plot from my Nano VNA (one of two) -- more poles would give you skirts that would have a greater depth of null before flaring out. The pass band rip

Yet another tool for your tool kit ~ The MMIC (Monolithic Microwave Integrated Circuit) Amplifier. The MMIC amplifiers are simply superb when looking for a module to add 20dB gain to a circuit, are termination insensitive, 50 Ohms in/out and low noise figure and good to 2GHz.  I first used MMIC amps in a bilateral 20M SSB Transceiver way back in 2010 and while it didn't make the cover of Rolling Stone it did make the cover of QRP Quarterly.   By far the biggest hurdle with using MMIC amplifiers is that they are surface mount and really small. They are incompatible with glue down Manhattan pads, Fat Fingers and require steady hands. Careful circuit layout is also a must!     12 Sq In. and 50% of a SSB Transceiver, A steered module with IF, PD/BM, Rx/Tx Mixer My AG393-86G MMIC Amplifier The devices you see above are Tri-Quint AG303-86G's which are now obsolete. BUT Mini-Circuits sells the MAR-6SM+ which is DC to 2GHz, with 20dB gain and a 2.3 dB Noise Figure with an application

A bit of magic is always a good place to start. With magic, coins appear from nowhere or perhaps with a bit of magic you can make your mother-in-law disappear. Or perhaps a new radio appears on your operating table with no idea how it got there. But as with all magic what appears to be likely is just an illusion. Yes, your mother-in-law disappearing was just a dream, and she is still there always telling you her daughter could have married a lawyer or doctor. For instance -- how did this radio get inside a Champagne bottle? Yes, it is a fully functional 40M SSB Transceiver!   Or maybe more fundamentally how with but a few hundred milliwatts of power long distance communication is possible?    In the 1970's Marshall McCluhan offered a simple paradigm that the Medium is the Message and a template for the Orange Guy for his political purposes. But our medium is ham radio and the tied at the hip connection to technology. Our message is that you have to know stuff to be a ham. For inst

  The $20 Radio Transceiver This is where you must be skeptical and say Too Good To Be True! Likely it is.  True out here on the left coast that $20 translates into about 3.5 Gallons of Gas and thus not incidental. Perhaps a slightly different metric, One Big Mac Meal with water. The subject today is metrics and how they relate to our hobby. But first a personal story about unusual metrics.  In 1984, I was working for McDonnell Douglas and assigned responsibilities as Program Manager to transition the Hughes Helicopters physical plant from Culver City to Mesa, Arizona and to build the new facilities to house all of the manufacturing and administrative operations.  Routinely I would brief Jack Real the then President of Hughes Helicopters on the project progress. Follow the link to read about an aviation pioneer.  At my 1st briefing where we discussed buildings sized at 300,000 square feet, he stopped me and asked that when I did future briefings that I convert the building sizes into

It is hard to keep up with the new technology hitting the market and what it can do for our hobby. Regrettably no time at the N6QW Laboratories to really explore all the possibilities but here is one that looks like it can be something useful in the shack. Over 15 years ago the Raspberry Pi hit the market and at that time was advertised as the full computer the size of a credit card and costing about $35. We are now on the Raspberry Pi5 -- but the $35 price point is significantly higher. On the other end currently available is a Raspberry Pi Zero W which is half the size of the original R Pi and less than $35 in today's dollars. Grossly speaking the Pi Zero has a faster processor than the original but somewhat limited in the on-board RAM and more like the original R Pi. By the way the Pi Zero W is a wireless version so affords internet connectivity. One of the very 1st projects I saw using the original R Pi was a beer dispenser that checked your ID before it would dispense the brew

If Brackets (or Analog VFO's) is not your thing, then today something for a weekend project. Another Swiss Army Knife is the 2N3904 NPN transistor. This device shows up everywhere and anywhere literally covering the audio to RF Spectrum. We are not going to showcase that device today! Instead, we will be sharing something about its twin complementary PNP brother the 2N3906, which also can also function from audio to RF. Often the PNP devices are bypassed because the Emitter is the + side and the collector is the ground side. It is tough enough to keep the NPN devices on the straight and narrow now you are switching pins.  The two devices (2N3904 and 2N3906) are almost equivalent in specifications as to the Ft and device dissipation. The tricky part is how to use both the devices in the same circuit. I have often mentioned the Plessey Bilateral amplifier circuit. For the anal-retentive blog readers, it is described in EMRFD, so it is OK to talk about it. I find it noteworthy that ma