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May 4, 2024. Making Sausage!

 The often-told story: You do not want to know how the sausage is made. (The same goes for Haggis!) But today I thought I would share my process on how I convert schematics to Circuit Boards that will be cut on the CNC. The process starts with two critical tools and those are the schematic and a piece of quad graph paper (.25X.25 squares). BTW for those ever welded to Manhattan (sort of Ugly type) construction this same process works FB. Our schematic in this case the 5894 RF amp has a lot of small parts that make up the total amp. In the old days this called for metal bashing, cutting holes in a chunk of aluminum and then finding all of those terminal strips. Lot of holes to be drilled and tons of nuts, washers and bolts! A fundamental pre-cursor is to understand how the circuit works and to also be confident you have not built in some unwanted feedback loops when you make the layout. The additional consideration is that this will be a compact sized amp and Circuit Boards facilitate
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May 3, 2024. If you were born in early February blame Cinco de Mayo

J ust a bit of Calendar magic today! But a fact that the 5th of May celebrations are just around the corner and is soon to be upon us. So, look at the calendar and see who was born in early February and count backwards. One of mine has a February 8th birthday. So, what was in the Gold Box? You have some serious clues provided to you. It is an accessory and is small in size. It needs power but has no Computer or MCU.  I could have been a "sneaky Pete" and dropped all sorts of hints like could it be a small enclosure with a 6" powered speaker inside. How about a Station Control Box? I keep saying I need these two things and certainly these two items fit the clues.  Maybe it is a microphone patch panel to switch between a Dynamic or Condenser Microphone and includes a Two-Tone Test Generator along with the microphones? I always wanted a SWR Bridge with a 4-inch 50uA meter on the front panel. That would be a really nice station accessory.  In addition to not being a new SSB

May 2, 2024. The Choices We Make.

There is absolutely nothing exciting about today's blog other than to share a bit of musing I did yesterday.   The occasion was sitting at the Board and Care Facility watching the British Baking Show (The same program series for about the 1000th time. Two of my favorite bakers are Sasha and Briony. Of note both have physical disabilities yet they both bake with the best of the bakers and just move forward.) When in such a mode my mind drifts off to thinking about new radios and projects. Thus, today I would like to share that thinking process with you. First out of the box is to question the end state objective. Is it to try a new technology or perhaps exercise a new gizmo hot out of Wuhan, China? Is it to solve a problem such as a retrofit of an existing radio that is not up to par? The big question, always, will I learn something from this project? If it is to build a warmed over Bitx with a new front panel, then the learning factor is pretty low.  Sometimes a new build focuses o

May 1, 2024. More output from your IRF510!

Every time I think or mention Mary Jo, somehow the 57 VW Beetle comes to mind. So, it is with the IRF510 and homebrew QRP rigs. They indeed are found frequently as the final RF Output device in our rigs. A really good thing that they can be had c heap --  as I have literally a ton of smoked ones sitting in a box.  Today's sojourn is to document on how I took what I see as the common circuit for this device and by changing the Drain voltage to 30VDC from 12VDC, I went from 4 watts out on 40M to about 10 watts. I can also Drive my SB 200 to 150 watts out on 40M. This is huge! Now don't get too excited because the IRF510 on 20M may not give you that big of a boost but it will at least give you 2X.  I ran this test a couple of weeks ago with a switching power supply and I could hear the supply in the radio. To resolve that matter I bought a used Condor 28VDC 1-amp linear (non-switching) supply from eBay. It does not have the noise issue and I got it for $25.   Add in a small sub-pa

April 30, 2024. Relive the days of yesteryear.

The banter on the air these days often drifts (not LC VFO's drifting) to the rig they are running. Most often it is a Yaesu or Icom and at the higher end is the FLEX or Apache Labs.   Notable very few if any homebrew rigs. Have you ever wondered about the SSB rigs being used in 1961? Those who owned a gold mine or were single might have a Collins KWM-2*, but many had Drake, Hallicrafters, National and the ever budget conscious Swan Rigs.  Herb Johnson who started Swan Engineering later Swan Radio was a visionary and started off by producing monoband units for 75, 40 and 20 Meters. The aim was Mobile operation as this was Cycle 19. I saw my first ever Swan SW-120 in February 1963 when I was a senior at Penn State. One of the professors had the SW-120 mounted in a Sunbeam Alpine. Later that same year when I headed out to Midway Island, I had a National NCX-3 -- should have bought the Swan 240! About 15 years ago I bought a SW-120 and two years ago the SW-175 and two weeks ago a SW-14

April 29, 2024. The J310 Direct Conversion Receiver

Recently I was asked what is the Simplest Receiver? Hands down it is the Direct Conversion Receiver! Today's post is to talk about that receiver topology made all the simpler by the Wizard of Portland and a new small board he will be selling. I have a couple of advanced copies of the board and want to share some info with you about a DCR project using two J310's as a DGM. You can find more info on the J310 DCR here . Consider this as leaking-edge info on Todd's new product thus sign up for his newsletter to get the release date and the pricing info. Go to https://www.mostlydiyrf.com  for the sign up. Some observations about the unit -- it is small and K7TFC has made it easy to use. There are holes at the connection points so you can solder stiff wires in the holes and make these plug-in units for socketing. In the event the range of your security blanket is limited to a Manhattan pad then with the stiff wire that can be soldered to the pads. In the most recent issue of the

April 27, 2024. Tubes or Transistors?

A recent acquaintance and newfound friend suggested I cover the tube versus transistor dilemma. Some Blog readers may even be saying why are you wasting my time with this subject. With a degree of certainty if you were born after 1960 then likely you have not dabbled a lot with tubes. So, it is somewhat of a question of familiarity with the use of tubes that will position most blog readers. There are definite pros, cons and negatives to the use of tubes.  Your antenna really doesn't know if the fire in the wire is coming from a tube or transistor. When I use my several pieces of Collins gear the station at the other end does not know that it is a tube radio until I tell them. Now if it was a Swan tube radio or perhaps a homebrew SS using an LC Analog VFO likely the other station would know because of drift in the signal.   The real negative with the use of tubes is that high voltage is present and can kill you. In line with the power supply concern is the operation in the field. T