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Showing posts from 2024

December 31, 2024. Last day of this year. Time to spend some money.

  Meet the $800 Xiegu X6200 Appliance Box Radio  This is a QRP radio with an internal battery that will produce 5 watts before a recharge (typically 4 to 5 hours) and touted as PFP (Perfect For POTA). It has a 3.7 out of 5 rating with several complaints like not good for CW ops and non-functioning out of the box. Who would buy this radio? Well likely lots of potential purchasers would. One of its advertised features is small size which is a boon for those who do not suffer from FFS (Fat Finger Syndrome). Yet another is that it is a Direct Sampling SDR which means that you must update the radio frequently to get the latest fixes to the problems that were inherent when shipped from the factory.  Hate to say it but you could get an ICOM IC7300 for less money and despite also being an appliance box has a proven track record.  I chose this subject and rig for today's spotlight if only to say choose wisely and read the fine print. I have an old car and likely the chewing g...

December 30, 2024. Throwing down the gauntlet challenge ~ A Thermatron Direct Conversion Receiver

With lots of time to think, but little time to build, and as we close out 2024, my thoughts turned to "why not a vacuum tube version of a Direct Conversion Receiver". Friends N2CQR and KK4DAS caused this thought aberration as they embark on a 2025 community build of a solid state DCR. Mind you this is just N6QW having a lot of time to think. Firstly, FOAM is still valid as a driving concept: Filter, Oscillator, Amplifier and Mixer. I see four tubes would be needed. Two 12BA6's, one 12AX7 and one 12AQ5. One 12BA6 would be at the RF Amplifier spot with the second 12BA6 used as the LC Local Oscillator. The 12AX7 would be used as the Product Detector and Audio Pre-Amp. Finally, the 12AQ5 is employed as the Audio Output Stage. The beauty of this specific topology is that much of the circuitry already exists for these FOAM elements. Some of these circuits are sitting in my Hybrid SSB transceiver design. No High School Science project involved here. The toughest part is the Loca...

December 29, 2024. A response to the soon to be Tariff Impact.

The always and forever is the better mousetrap! A tour through eBay yesterday was an eye opener. I actually was looking for crystal filters and saw a bunch under the ICOM section. The FL-30, a 9 MHz, 2.3 kHz wide SSB filter can be found in many ICOM rigs of the past. These are currently priced in the $20 to $30 range. For tighter skirts the FL-80 is a good selection.  A tighter skirt on a shapely YL is better and so take the hint when it comes to filters. My tenet for those 1st time builders who want to build a SSB transceiver is that you buy a commercial filter as a first step build. After you get your homebrew rig working and working properly, then and only then, take up the science project of homebrewing a filter.  You want your very 1st HB rig to be a success, and a commercial filter puts you way up on the curve. Later on, you can fiddle and fool around with the math and crystal selections and even use that untrustworthy Nano VNA you have. I have several radios with homebr...

December 27, 2024. It is time to resist. Join the Resistance Movement!

This is not a political posting but instead an opportunity to address some serious issues concerning our hobby. At one time it was not the number of hams who were licensed that was the metric but that those who were licensed hams all had a level of technical chops. The ARRL in a move to increase advertising revenues fostered the get more hams licensed by dumbing down the licensing requirements.  ARRL's own data shows about 770,000 licensed US hams today but only half of that number have full HF privileges. The rest have a Baofeng UV 35R handheld. Many of the technical advances in our hobby during the period 1940 -1970 were a direct result of ideas and products developed in ham shacks across the US. Some Internet Data (not independently verified but likely close). 1939 about 51000 US licensed hams 1950 about 90000 US licensed hams 1956 about 140000 US licensed hams 1970 about 270000 US licensed hams 2024 about 770000 US licensed hams So, what this tells me is that there was a 5-fold...

December 26, 2024. I got a SUV present for Christmas.

  Another Christmas and another SUV present -- Sox, Underwear and Vitamins. I did get some neat presents though including a book by Mark Harmon (NCIS alum). The book is about WWII entitled Ghosts of Honolulu. It should be a good read. Speaking of NCIS (Naval Criminal Investigative Service) during my last tour of duty in the Navy I had a collateral duty as Legal Affairs Officer and routinely worked with the NIS (Naval Investigative Service) the forerunner of NCIS. About two months before I was to complete my four-year obligation, they tried to recruit me to join their organization. I asked one question well actually two. Number 1 was what was the pay and Number 2 would I have to carry a gun. The pay was poor, and the gun answer was always.  I gave my country four years of my life and so opted to work for AT&T Long Lines. That was a good choice.  Kind of a year-end rant. I don't like what I see shaping up with the new government that in less than four weeks will assume ...

December 24, 2024. Twas the night before Christmas!

Twas the night before Christmas and there was no RF in the Shack!   No RF is a good thing too!  Christmas is a time for family and to reflect on the good things and perhaps cleanse away the bad things (that is the more difficult task). We should never take life for granted as there may actually be no tomorrow. So, enjoy the good stuff today and maybe use this time to chart a project for 2025 where you actually build something. Actress Terry Moore circa 1947 The world is unfair. I have many projects I would love to build but have no time given my caregiver duties. Yet you couch potatoes out there have the time but no interests other than looking at IC7300 Menus.  Several days ago, I posted a photo of Terry Moore, the actress. No one flinched or asked why! In the early 1950's Moore was part of a USO tour entertaining our troops in Korea. It was winter and Moore appeared on stage in a white ermine bathing suit. It was a big hit with troops but not taken well by the WCTU (Wom...

December 23rd, 2024. It is with a sad realization -- the era of homebrewing is almost extinct!

The era of homebrewing a rig is very much on the decline if not almost gone. Perhaps less than 1% of US hams ever build anything. (That set is about 7700 hams and possibly much less than that as 1% of the US Hams with HF privileges is half that number or about 3800.)  N6QW's 40M DCR ~ MC1496 Based The availability of ham radio products literally overnight is staggering. If it is not something advertised on eBay, then Jeff Bezos has it. Typically, the pricing is pretty fair and thus no need to whip up something in the lab. You can buy it and have it in hand faster than you can make it. [My daughter had an accident a week ago where she broke a rib and was in the hospital for two days. She is OK now, at home and will be joining us for Christmas. We all know about hospital food -- so she got Door Dash to deliver her food in the hospital -- all she took with her to the hospital was her iPhone and a Credit Card. Same thing with ham gear and electronic parts.] Then there is the pervasive ...

December 22, 2024. So how do you turn a Direct Conversion Receiver into a Transceiver?

Friends and colleagues, Bill, N2CQR and Dean, KK4DAS, developed a Direct Conversion Receiver project that was featured in "hackaday" and the subject of a local High School STEM type project. Actress Terry Moore (now 96) Read about her in Wikipedia If you have listened to or watched on You Tube the SolderSmoke Podcasts #254 and #255 then you know this has been the subject of a challenge to another podcast group and to the ham community in general. Dean, KK4DAS in January is sponsoring a 4-week Zoom Buildathon to construct the DCR. W7ZOI Original DCR Circa 1968 The N2CQR/KK4DAS DCR designs builds upon the FOAM concept championed by Farhan, VU2ESE. FOAM is an acronym for the four parts of the DCR: Filter, Oscillator, Amplifier and Mixer. See if you can spot the FOAM pieces in the W7ZOI design? Because Bill and Dean know stuff, if you follow along, you will be able to do stuff. But I opine that just building the DCR while it adds to your knowledge base and provides a deep sense o...

December 21, 2024. "Miss Congeniality"

Sandra Bullock is one of my favorite actresses and one of her movies ends with a bit of a wish for "world peace"! Indeed, a great thought that as of today is not in clear focus in the foreseeable future. There is just not the appetite around the world to work cooperatively and if anything, it is every man for himself.  That was clearly demonstrated here in the USA just a month ago. Bad decisions any time, any place, and in any venue are difficult if not impossible to undo. There is no reset button for those who make bad decisions! But a really good decision is to take our hobby back to its core foundation where ham operators would actually build things. There is both the learning aspect and the satisfaction aspect, and the end result is something useful.  It doesn't have to be a self-designed SDR transceiver but something as simple as a dipole antenna or perhaps a Stockton Bridge SWR meter. Avoid kits as there is just about zero learning with a kit other than how to unbox...

December 20, 2024. A Case for Zuppe Inglese

With Christmas but 5 days away, my thoughts have turned to homebrewing special dishes traditionally served only at this time of year. Speaking of traditions, we had one at my home when I was growing up.  The tradition was that on my birthday (December 18) the Christmas tree would be decorated followed by a birthday party. For a birthday cake my mom would serve Zuppe Inglese. Literally translated Zuppe Inglese means English Soup -- but it is so much more than that description. So here is my mother's version of Zuppe Inglese. You start with four layers of white cake. Each layer is liberally soaked in rum and between the layers is vanilla cream pudding. The outside is covered in real whipped cream and topped with Maraschino Cherries. The cake must be made 24 hours in advance of consumption so that the rum flavoring fully permeates the cake.  A variant likely developed to solve a problem. One traditional Italian cookie is known as Biscotti (the root of the word biscuit). Believe i...

December 19, 2024. The Day After.

Yesterday was my birthday and I suspect Brad Pitt had a much better time celebrating than I did on our shared birthday. But I did buy myself a small cake with the requisite one candle and thanked God for still being alive That said I did receive birthday wishes from as far away as Bangalore, India, a couple from the UK, one each from Australia and Italy and a bunch from the USA. It was nice to be remembered. In two weeks, it will be 2025 and three weeks after that, a new administration will be running the United States. There are troubling signs of what the next four years will be like here.  Clearly already there are words of retribution and revenge mixed with individuals in key positions who clearly lack the experience. But you who voted for this option are now stuck with the results. One must ask what have you done? There are now less than five weeks to buy that new rig from the Far East before the price impacts commence from the new tariffs. 73's Pete N6QW

December 18, 2024. Happy Birthday Brad Pitt! More on the KWM-2 Switch Fix!

Friend N2CQR posted my KWM-2 Power Switch Fix on an Antique Radio Forum and of course that prompted a posting (possibly from the resident blog police person) that in essence said that is not the way to do it. The blog poster also mentioned something about using relays in the 516F-2 power supply. In truth, the relay in the power supply is a better solution and now I will show you how that is done. But what the blog poster police person forgot is that to enable the relay in the power supply you still need a working switch in the KWM2 or 2A. So, step #1 fixes the switch and step #2 installs the relay. The theory of the relay has as its roots in what is called the Motor Start Circuit . If you want to start a 50HP motor, you do not use a toggle switch in line with the motor. But what you do is to use the toggle switch to control the field coil of a 50HP rated contactor (fancy name for a really big relay) where our field coil draws hundreds of milliamps while the contactor pulls in the curre...

December 17, 2024. WWII Spy Radios

Things show up on my phone especially when I search through You Tube. One of the recent videos to appear on the screen was "Spy Radios" from WWII. Generally speaking, we might see these as pretty crude in comparison to what we have today. Often these radios were simple two tube regenerative receivers (6SK7) and a one tube transmitter (6V6). One of the more famous of these spy radios is the Paraset shown below.  Developed by the British SAS, it is officially known as the Whaddon MK VII. Often the array of items above were packed into what looks like a beat-up leather suitcase so it could be easily concealed and transported. The name "Paraset" came from the fact these were air dropped with the spies behind enemy lines. Power could be supplied from the mains or a 6VDC car battery using a Vibrator power supply.  Surprisingly it is a two-band rig covering the 80 and 40M bands and with a 6V6 transmitting tube (Crystal Controlled) you could get 5 or 6 watts from the Parase...

December 15, 2024. New You Tube Video Just Added!

You Tube ~ Power Switch Repair One of the various known maladies of the KWM-2 (did I also mention it sucks on CW) is the failure of the main power ON OFF switch. When this switch fails you are SOL, and I was in that boat! [ What you are about to read is a solution to the power switch failure that was successful in large measure because of experience, tribal knowledge, and engineering genes. Having some nifty tools like a manual milling machine was also key. Also, significant in the fix is a well-stocked junk box. Soak in what was done as you, the reader, may have a problem like this one at some time and you can refer back to the N6QW solution.] In the upper left-hand corner of the KWM-2 and KWM-2A is a four-position selector switch that reads OFF ON NB CAL. It is a standard wafer switch but ganged to the non-round shaft of that switch is a second switch which only operates in going from OFF to ON.  We see this setup typically on Volume controls that also have the Snap Action switch...