Sunday, October 27, 2019

When you know Stuff, You can do Stuff!

A Reflection on our Hobby!

First and foremost we must recognize that for most ham radio  enthusiasts it is a hobby. Yet, for some in our ranks it is a stepping stone to a business. Many, if not most, well known lines of ham equipment had their roots in a ham's garage or basement shack. Collins, Drake, hallicrafters, FLEX and Elecraft come to mind. 

We also should not forget the modern day counterparts like Ashar Farhan and Hans Summers with the Bitx and QCX.

The founder's of these companies knew "stuff" well before they came up with the 3000 menus to operate their rigs. 

My particular "burr under the saddle" is that many of today's hams know the 3000 menu's; but nothing about their rigs, how they operate or how to tell there is a problem with their equipment. Regrettably many of these same recent vintage hams currently hold the US "Extra" class license.

I have received some email telling me to "knock off" denigrating the newly minted extra's using the term BTE (Box Top Extra). There is much validity to not lumping all newly licensed Extra's in a class, where all are called BTE's. 

Statistically there would be a strong argument to saying there is a bell shaped curve where some are and some aren't. So to those who fall on the portion of the curve as having the skills commensurate with what the licenses requires, my apologies. My experience however tends to support that in the new crop of Extra's the "skilled" percentage is being on the less than 50% side.

However judge for yourself, as one only need to listen on the air to the call signs, often easily identified as being extra class, and what is transpiring to support my assertion.

Here are some examples I have personally experienced (this is current experience not something 40 years ago). About two months ago, I was listening on 40 Meters to two stations trying to make a schedule. The weaker station kept saying to the louder station "you are distorted", "you are distorted". Well the louder station was not distorted! The problem was they were not on the same frequency! 

I tuned in the louder station and called him identifying myself and stating: You are not distorted --but you two are not on the same frequency. Astonished -- he said OH. I then tuned down to the weaker station and identified my self and shared that the other station was not distorted; but they were not on the same frequency. His curt reply to me: "There is nothing wrong with my rig!" Yes he was an newly minted Extra! 

I then suggested he tune his dial a bit or check that perhaps he had his RIT engaged. Back again to me, only with real anger: There is nothing wrong with my rig! 

The first issue for this BTE is that he totally discounted that there may be something amiss --not that there is something wrong with his rig but in fact an issue of zero beat or that the RIT is engaged. 

There is another possibility, while he was reading his analog dial, display or a block on a computer screen what he was reading may not be TRUE. In fact there are possibilities such as can occur with my beloved Si5351.  The frequency being read on the display is what is being generated by a computer command. But if the Si5351 has not been calibrated then the actual frequency being transmitted may be different.

Even with my wonderful RADIG which I calibrated against WWV was found by another station using a Rubidium Standard locked to a GPS was actually 14 Hz off frequency. Before I calibrated the Si570 in that rig, there was a 2 kHz spread over what was shown in Quisk and the real frequency. The BTE did not and does not acknowledge any such possibility. In reality he probably does not know how to check if that is the case.

Then take the case I witnessed where again a newly minted Extra (it must be a 40M phenomena) had RF in his audio. I was just listening to others trying to help this person. The help from others was a very logical approach to fault isolation. 

First he was asked if he was running an amp and if so turn it off. No amp. Next he was asked are you running a speech processor. The answer was yes, and he was directed to turn it off. 

That helped but there was still evidence of RF on his audio. Next he was asked to check things like his microphone connection  and if it was fully connected or did a ground come loose. He also was asked to look at his coax connectors and connection to the antenna.

His reply was that he hadn't done anything to those connections and so that could not the issue. His final comment was that since shutting off the speech processor helps his signal -- he was done. Yes he was a new Extra! I later heard this same station -- he must have turned the speech processor back on as it was awful.

He was in denial of what at least four stations were telling him about the quality of his signal.

But let us back up to about 100 years ago when our hobby got launched. It was a simple B and B! You had to Build your own rig as you simply couldn't get on line and Buy your rig.

When you build something, you have to learn stuff, you have to know stuff and you have to do stuff. Buying a rig only requires that you have headroom on your plastic card!

Some examples of stations that were homebrewed. Sorry guy's, but I think these rigs look kind of cool!

Today there is little Building in comparison to the Buying of radios. It is a rarity for me to have a QSO with someone using home conctructed equipment. At times you would hear --- I used to build stuff but the stuff you build is no where near what you can buy. 

Kind of faulty logic there. Once I bought a VW bug as a work car -- since I only had to travel 4 miles on surface streets and my VW was parked out doors where at times the OAT was 100F. I had gloves in the car because the steering wheel after a day in the sun was too hot to handle. Did it get me back and forth to work? Yes! Was it reliable? Yes! Was it inexpesnive to operate? Yes! Could I work on the car myself? Yes! Did it have AC? Yes --the 2 X 40 kind. You rolled down both windows and went 40 MPH! Was it a Cadillac? No!

The Key here is that when you build stuff -- you have to know things such as when it is operating properly and when it is not. It is this latter case where you also would reasonably know how to fix what is broken. 

For a novice --that might be the initial starting point as you are just starting and do not have the depth of experience or knowledge base. 

For an Extra Class more is expected. The ease with which Extra Class Licenses are obtained ( I should say awarded) puts a percentage of US Extra Class Ham's in the category of a person with Extra class previlieges but having only Novice skills! 

Was the weakening of requirements (by the ARRL) for the Extra Class license purely a ploy to sell more high priced "appliance boxes" and in turn produce more advertising revenue? You judge but the evidence is more than circumstantial!

A really good example is my RADIG -- it cost me $150 and has many of the features of radios costing 10X. But, I had to scratch build it! 

True, there are indeed newly minted Extra's who build their own gear and take on a serious quest to learn about the hobby. But I would place them in the minority not the majority. 

Yes I am a degreed EE, have been continuously licensed since 1959 and have been an extra since 1977. Do I know everything --well let's say I don't claim to be a stable genius like our emperor (with a small e)? But I at least try to find out why my rig may not be working properly. Plus I do believe all information is good information. 

If someone reports to me something strange about my signal -- I want to know why and since I have invested a lot of time learning about the hobby I usually have a pretty good clue about the problem and more importantly the fix.

Or has our hobby turned into something where we believe something that it is not. Much like our friend here who thinks he may be a chick magnet. To him I say -- you are missing the beret!

Pete N6QW

Thursday, October 24, 2019

A letter sent to DX Engineering

Are we being manipulated by the Ham Radio Manufacturers?

Here is a letter that was sent to DX Engineering?

If after reading this you have similar views --why not drop K3LR a note at the DX Engineering website "Contact Us" tab. I am sure he would love to hear from others in the ham homebrew community who like me see $4K for a Appliance Box as being out of step with our true ham roots which are now over 100 years old!

10/26/2019 ~ PPS (Pre Post Script). 

When you have the innovative and experimental mindset, then it is possible to add some new technology to fix problems with older radios. One does not learn that by knowing the 3000 menus in the IC7300. A Ten Tec Model 540 had a completely broken dial cord mechanism. Yes. radios used to have dial cord mechanisms. 

The message here is "when you know stuff, you can do stuff"! Working Contests and Operating may not give you the skill sets to pull this off. Watch the video...

October 23, 2019

Dear Tim, K3LR

Thank you for sending me the latest DX Engineering catalog which clearly displays radios and equipment that are simply not affordable for an OT like me who lives on a fixed retirement income.  Spending $4K for a radio is simply not in my budget; but that does not mean I am not on the air with some very modern equipment!

Your lead piece on page two sums it up quite nicely –endless possibilities. Recently I “homebrewed” a fully functional SDR transceiver for about $150. The reason this is possible is that there is so much amazing and cheap technology that makes this SDR rig a reality. Notice I didn’t say radio as that has implications of an appliance box! 

For a computer I am using a $35 Raspberry Pi3, the Sound Card was $15, and the USB Frequency Controller was $30. A lot of the critical hardware was obtained as free engineering samples and includes two ADE-1’s. Yes, it’s on a bread board.

The display can be an older LED TV that has an HDMI port and of course a keyboard and mouse. The driver stage is a 2N2219 and the final is the IRF510. The SDR Software is a free download from N2ADR known as Quisk.

Above is the typical Quisk spectrum and waterfall display just like the Big Boys with the $5K radios; but mine cost me $150
This now leads me to the remainder of your piece about Elmer’s. Seem like things have really shifted over the 60 years I have been licensed. Today’s Elmer seems to serve the function of what is the best antenna to purchase from your company, or how to navigate the 3000+ menus on the IC7300. In my day Elmer’s were the technical resource for knowing each and every component in a circuit and how it is applied, and the “why” it is there. Oh, that’s right now you send in a box top and get an extra class license and then spend thousands for a rig you have no clue how to operate.

It is with interest that your Elmer goals seem to follow what to buy, how to operate in contests and a friendly voice that says buy a FTdx101D. No where do I see a fostering working with and/or building your own radio using the latest technology. I know you have done marketing analysis to identify the demographic with the most $$$ and the new crop of rigs are priced accordingly. 

In a recent vintage ARRL Bulletin it was a position of the IARU that hams are hams for two reasons: Contests and Operating. Certainly, that is good for your business; but that position ignores what hams of my vintage did and do today. They were innovators and experimenters. Just look at Gerald Youngblood who took the concept of SDR and now he along with Raytheon are developing the next generation of communications systems (SDR Based) for the US Air Force. Suppose if K5SDR only wanted to operate and do contests? Side note, Raytheon used to be a ham equipment manufacturer. If you have ever happened to look at the nameplate on a late Model of the famous SBE transceivers – yes a unit of Raytheon.

My real point is that you might want to consider offering more “homebrew rig” kits so that we continue to foster the innovation. Besides you might actually hook a few more customers for the big box appliance stuff.

Now below is an example of where I built a solid-state version of the Collins KWM-2 which I call the KWM-4. Not every one could pull this off – but here is another endless possibility.

This is a multiband, dual conversion (10.7 MHz and 455 kHz) all solid state QRP rig. It involved some critical thinking and with the exception of the remote keypad and the Digi VFO the whole design and construction was done by me. As you can well guess I spend lots of time on the fabrication side, little time operating and no time contesting.

Since DX Engineering has become such a Big Gun in our hobby and regrettably the ARRL only wants to sell advertising for unaffordable radios, perhaps this is a time to be a true Elmer and foster and reincarnate the original “homebrew” spirit of our hobby. I invite you to visit my webpage and my three websites. , and Hopefully you will see I have built more than one radio.

Pete N6QW

A Bit Of Wizardry -- When You Know Stuff, You Can Do Stuff. My Extra call goes back to 1977 in case any one wondered.

Thursday, October 17, 2019

ZL2BMI Challenge Rig

Hmmm... There WAS a Quid Pro Quo! Source: Mick Mulvaney!

BUT! It was just a little bit of Quid Pro Quo!

Fit Check of the Boards to meet the ZL2BMI Challenge Rig!

But first a sharing of a bad experience (much like having an emperor [with a small e] ruining this country) I had on 40 Meters the other day. My friend Bill, N2CQR has been making CW contacts running a mere 80MW on 40 Meters. 

Not to be outdone I removed the IRF510 stage from one of my homebrew SSB transceivers and got on the air with 500MW SSB. I awaited a very strong station to sign and then gave him a call. He acknowledged my call sign and then I asked for a signal report since I was only running 500 MW.

His response was astonishing: He said I should get off the air as my low power caused him to increase the gain on his receiver which in turn made his shack noisy. Get a decent rig was his final comment! There was absolutely no comment about a bad signal --it was just a weak signal. He probably was wearing his MAGA hat too!

His comment and attitude is incompatible with being a ham! Perhaps I should make a youtube video of this experience and identify his call sign. He just might deserve a bit of youtube shaming from those who follow my 170 videos.

Below is a test run of the Band Pass Filters (Rx & Tx) that will be used with ZL2BMI Challenge rig. A couple of years ago I purchased some alternate 10.7 MHZ IF Transformers as the 42IF123 units were disappearing. I just  stashed them away as they looked kind of small --well now they look just perfect!


Progress on the ZL2BMI Challenge Rig!

Above is the schematic for the "guts" of Eric's transceiver. In the center is a  board that is 2.25" by 1.875" where I am doing a fit check of components. You can see the SMD version of the SA602 as well as the SMD of the LM386, There is also data for the matching transformers. BTW I got the carriers for the SMD from Marlin P. Jones & Associates located in Florida.

I have already incorporated some changes with a BPF going into Pin 2. This BPF consists of two 10.7 MHz IF transformers back to back coupled with 4.7 PF and 150 PF (NPO) padded across the windings. I have installed a BPF just like this in a working transceiver -- so I know I am good to go. The output BPF is a duplicate. These are the 4 black dots at the top of the board. The Zin/out of the SA602 is 1500 Ohms so we will need a match at Pin 1 of the 1st SA602 and at Pin 5 at the 2nd.

I may also pop in a 2N3904 ahead of the LM386 and a very small panel mounted 10K audio pot.

The crystal filter uses the same filter crystals as used in the one that was plotted in a prior post. 

I have also been working on the Arduino code for a 1/2 size Blue OLED. This VFO has two frequencies with the 2nd default frequency being FT8. So Cool!

Stay Tuned!

Pete, N6QW

Monday, October 14, 2019

"The emperor (with a small e) told me there was no quid pro quo!

Four Pole Crystal Filters!

I hate homebrew crystal filters! They are difficult to build and unless you have:
  1. A decent process to build one and
  2. Decent equipment to measure what you have built you will be doomed to failure. 
  3. A typical result failing 1 & 2, does and will sound like crap.

Given the recent article in the GQRP SPRAT by ZL2BMI for a tramping SSB transceiver I have given pause to building another small transceiver --- very small. It is a sort of challenge from ZL2BMI as in a recent round of emails between Eric & myself resulted in his stating: "Mine is SMALLER than Yours". 

I shared that my shirt pocket SSB transceiver is only 16 cubic inches to which he shared that his rig is less than that and that it has an OLED display. Mine used a crystal switched VXO covering only about 60 kHz of 20M. His is a tri-bander for 160-80 -40 Meters. 

So you now know where I am headed.

Firstly I did build a four pole filter using 4.9152 MHz crystals. You can see the plot below! Man that is text book and using the Antuino I now can find the Filter Center Frequency. It will also help me make a 1st run at the LSB and USB BFO frequencies. I used 47PF coupling caps so the BW is wider than I normally use --but it will have presence and not be yellowy! I also only had 47PF in SMD.

JFF (Just For Fun--that must be what the emperor (small e) did when he made his Syria decision.) I installed the filter in a working 80M SSB XCVR and also built an outboard Digi VFO. It works!!!!!!!

Stay Tuned as I work on the ZL2BMI SIZE challenge.

BTW there are some really creative folks in the world. Here is a great example of some high level creativity... Could this be a reality?


More Attorney's Get Attorneys!

Some current government appointees  will certainly need attorneys as things ramp up!

Pete N6QW

Wednesday, October 9, 2019

It is like the very famous Agatha Christie Novel...

[Thomas Paine Must Have Had Future Vision!]

As I sit riveted to cable news, one thought keeps surfacing, that great movie based on Agatha Christie's novel. Yes, I am talking about Murder on the Orient Express!

The ending of the movie shows clear evidence that they all did it! 

Wow that was a shocker! Now we have those foreign country scandals and more players are "being rounded up in the list of usual suspects". (Like in the movie Casablanca.)

Is it possible that the drag net becomes so large and snares so many that the final outcome is we have the first female President? Wow that is sure to give rise to a lot of sleepless nights for the emperor (small e) and his retinue. Look what the dragnet turned up. Some in the Italian community are now calling Rudy IINO (Italian In Name Only).

My soldering iron is cold as I try to keep a scorecard of who is who on the list of alleged suspects.

Is there that one possibility --they all did it? 

We also think of that famous line from Shakespeare. "Me thinks he doth protest too much."

Stay tuned to cable news-- the best parts are yet to come. 

There was a trial balloon premise on one of the internet news sources... President Pence … wow some one is sure moving the needle fast forward.

Some in Washington today might be thinking of potential future attire in lieu of those $3000 suits they now wear. 

BTW the Orange Jump Suit comes in Size 3X --easily will fit a large man or woman -- about 250 pounds is max. 

 So OK -- some ham stuff …

Friday, October 4, 2019

There is just Something about Innovative Mechanical Engineering

Mechanical Engineering in our Radios, Rigs and RADIGS

Being hams, we often think about the electronic hardware in our rigs. Does it have an IRF510 in the Output or a Real RF Device like a RD06HHF1? Is it being "Run" with a digital VFO or one of those drifty, shifty Analog boxes.

BUT we often forget that some of these beloved radios rely heavily on our brother Mechanical Engineers to make it all play. You only need to look at James Millen who did all of the ME on the HRO receivers. Or pop the hood on that Collins R390A and savor the mechanical tuning mechanisms. Perhaps you overlooked the same in your KWM-2 or Drake TR-4. The ganged tuning of various networks is a marvel. Hey don't forget the SBE-33/34 and the "Geneva" Turret tuning arrangement.

But there is a special place in my shack for those really "cool guys" at Ten Tec. If you perhaps have some earlier Ten Tec radios like the 505, 509 or 540 that string driven dial system was pure Mechanical Engineering as was their PTO's. Can you imagine -- you could rebuild your PTO right at your kitchen table -- pretty clever.

But at times some of the Mechanical Engineering was hidden behind the panel and we simply used it without giving it a second thought. The Model 540 has a band switch located in the lower left hand corner of the radio. Actually it is THREE band switches with two visible on the front panel. When you put the main band switch on 10 meters you have an additional 4 position switch that is engaged to give you four band segments. But there is a third hidden band switch that is engaged as you change bands. Here is that Mechanical Engineering stuff at work

Before you gulp -- this is a Model 540 that was upgraded by me to a Model 544 and was the subject of a QRP Quarterly article in 2013. 

When we think about the Model 540 and the principal band switch you must think about what that switch is really doing. It has many jobs/functions. 

The way the frequency scheme of the  Model 540 works is to have a singular fixed VFO range operating at 5 to 5.5 Megahertz --yes you guessed it a 9 MHz IF. But to work the various bands this basic VFO signal is mixed with various crystal frequencies to produce the LO Signals that results in the 9 MHz IF --it is a single conversion radio.

Now we have all seen the 9 MHz IF and 5 MHz VFO that gives you two bands -- add the IF and VFO and it is 20 Meters. Subtract the VFO from the IF and you have 80 Meters. But you do have to pay attention to any possibility of sideband inversion.

But Ten Tec used  for all bands except 20 Meters a VFO signal that is crystal mixed to give an injection frequency above the incoming signal on 80/40 Meters and then for 20 Meters and above the LO injection is below the incoming with no crystal mixing on 20 Meters.

So this mysterious hidden band switch is THE mechanism that "on's" the crystal mixing for the various bands. 

Another Mechanical Engineering problem -- packaging. The Ten Tec Model 540 and Model 544 were very "desk top" friendly having a very small compact footprint. Thus a very long shaft could engage many band switch segments to engage multi-function circuits. But you are faced with the trade off of long band switch size and compact footprint.

Another function of that band switch was to switch in various LOW PASS Filter Networks following the final amplifier "brick". Along the way other circuits are switched into play with changing of the band switch.

Did I mention yet another Mechanical Engineering problem -- circuit shielding and isolation. That crystal oscillator and mixer circuit were shielded--yes in a shielded box there is also a MC1496 DBM that mixes the Crystal Frequency with the VFO to produce the proper injection frequency. Another wafer on that third band switch adds some filtering to the output of the driver stage ahead of the final amplifier brick. Believe it or not -- that wafer is mounted on the back side of the shielded box, right adjacent to the driver board.

Oh more ME stuff -- all of the major circuit boards have through board pin connections that on the bottom end plug into chassis mounted sockets and actually protrude through the top side -- this give you access to literally hundreds of test points. Smart Mechanical Engineering!

Back to our third hidden band switch. So if this switch is not on the same shaft as the main band switch how is it engaged. Enter a piece of brilliant Mechanical Engineering which I call "a slider crank mechanism". Two mechanical linkages affixed to the main tuning shaft essentially clock the third band switch so that when you place the main band switch on 40 Meters the Crystal Oscillator puts in line a 11 MHz crystal so the output when mixed with the 5 MHz VFO output a 16 MHz injection signal results. When that injection signal is mixed with the incoming signal at 7 MHz the result is 9 MHz at the IF. 

BTW if you look at the Model 540 BFO, a single BFO frequency will result in the "Normal" sidebands for all of the ham bands and with a bit of capacitor padding will shift the BFO frequency to the "Reverse" sideband. Ten Tec does not call them USB and LSB. I keep digressing

Here is a photo of that slider crank mechanism. Essentially what you have is two pieces of metal coat hanger with a loop formed at each end. These loops fit around a drum like spool assembly so that as you clock the band switch the coat hanger material is free to move around the spool; but the push pull action moves the third band switch in unison with the main band switch. If you don't know that the spool assembly comes apart and you somehow get the metal, bars out of the spool -- they simply cannot be fed back in place without removing the cap

The reason I mention this is that I have a project on the bench where the "slider crank mechanism" was in shambles, the dial cord was chewed up and it was obvious some non-engineer maybe one of those BTE's tried to "fix" something without knowing what they were doing. Pretty obvious who they voted for in the last election.

The metal bars were pretty bent up and I did a bit of straightening. The interesting engineering aspects of the nylon assemblies that fit on the two shafts they are molded so that the fit only one way on the half moon shafts of the two band switches and the bonus --there are really small set screws that further lock the nylon pieces to the two shafts. 

Good thing I have acquired many small Allen wrenches. BTW the same Allen wrench that works with the main tuning knob will work with these set screws on the nylon assemblies. This is a long term project and you will be amazed at the final product.

Pete N6QW

New Technology for 2020 ~ Improvise, Adapt and Overcome

What to do during the Pandemic? This is a chance to get back on the air or to take up an interest in homebrewing your own rig. You can bui...