On The Inside

On The Inside

Tuesday, May 26, 2015

Crystals in Plastic

Just crystals, in plastic bags. I call it "Crystals in Plastic"

Their resonance is trapped, constrained by man's excessive need to organize, they are left insulated from the electronic world at large. Although free to connect with each other, they find the excitement wanting.

On the shoulders of giants...
(Available in a print)

Brothers - A Bunnel 6B and a Mizuho QP-21 pcboard.

Wednesday, May 20, 2015

On Filter Response

In a previous installment I showed a filter pulled from a CB radio. I've been battling with the filter impedance thing for some time now and can't seem to get a good method to reliably determine filter impedance. Here's my simple test set with two series pots and a couple of fifty ohm shunts.

So, you're supposed to adjust input and output for the best filter shape. Yeah, that's easier said than done.

I have found the process of trying to determine filter impedance empirically without the aid of expensive test equipment frustrating to say the least. This little diversion started because I wanted to measure the impedance of several filters that are in my junkbox, in particular, this nice little filter that came out of a Sears Roadtalker 40.

The way that this is supposed to work is that you put the filter into the jig, attach the input side to your sweep generator or noise source, the output side goes to your scope or spectrum analyzer, and you adjust the input and output knobs alternately until the ripple in the passband is minimized.

Great, that sounds easy-peasy!

Well, the devil is in the details. First, if we use the noise method, at least with the gear that I have, it is challenging to see the passband ripple in the noise, Ok, no problem, I'll use the sweep method. I have a couple of different sweepable generators, one of them should get the job done, right?

Generator #1

It's a BK-Precision 4040A. I'll say this, choosing the word "precision" as a part of your brand name is a stroke of marketing genius. Unfortunately, I don't think that the engineering department got the memo.  It's not useless, but I'm not really sure for which application the sweep function is intended. There is no sweep output so you cannot use the sweep generator to drive the X input of your scope in XY mode. If you do use the sweep function, it's very touchy and extremely wide, too wide, in fact, for adjusting a crystal filter. It does have a voltage control input which would be awesome if the start and end controls scaled an external ramp input, but  no, it's an unscaled input that is virtually useless without taking the time to put together a scaling jig.  The manual states that the input takes 0-10V ± 1V for a 100:1 frequency change. Great, plus or minus ten percent of the input range, that must be some of that precision.  Ok, enough bagging on the BK, mine was a craigslist find, it still gets some use. Speaking of bagging on the BK, you can order a handy tote! Ok, for real, enough bagging on the BK.

I also have an old HP signal generator, the ubiquitous and somewhat infamous 8601A. I say infamous because they are so well known for blowing their output amplifiers, which are made of unobtanium, that someone has re-engineered a replacement. Unfortunately for me, I think that 1) my output amplifier is blown, and 2) that the $90 cost is too high for me to justify repairing this old girl.
This lovely example is much cleaner looking than mine and also has the RF and aux outs routed to the front like any sane person would expect. Ok, I can see the value of having the cables out of the way for fixed applications, but that wasn't going to work for me.

First things first, a bit of testing. Sweep output hooked up to the X input, scope in XY mode, blanking out put hooked up to the blanking input, check!  I forgot to snap a picture, but, the blanking is reversed, the retrace is bright, and the sweep is dim.

I wired up a quick inverter using a 741 and connected it in line with the blanking signal.

This gave me a relatively nice looking sweep signal and I could get good blanking just by tweaking the intensity control of the scope. 

It's not quite that bright in reality, I used a long exposure on my camera to get a good trace picture. However, you can clearly see that the retrace (the falling edge of the ramp) is much dimmer than the sweep trace. The flat portions at the ends of the sweep cause the sweep to be fixed for a period of time at the start and end of each sweep. This makes it easier to setup the scope and signal generator.

Although the op amp worked well, there is no bipolar power supply that's easy to use in the 8601. I could make a simple zener supply from the +26 and -6 volt supply rails, but there isn't a lot of room in this thing so I decided to simplify the design. The op amp does a proper inversion around the ground point, but strictly speaking, that wasn't necessary, I just needed a change in the polarity of the blanking signal. So I replaced the op amp with a simple inverter made from a PNP transistor so that I could power it directly with the negative supply rail referenced to ground.  While I was at it, I put the generator on the repair bench to move the connectors around to the front. That way I could use the holes in the back for a new blanking output and a switch to disable it when I didn't want to use the sweep generator with my scope. It's a lot less hassle to reach back and flip a switch than it is to move both the scope and the generator just to connect a cable.

Here's the little inverter, built on a bit of perfboard, ready to be tucked into  the back.  The green wire is the inverted blanking output and the other three wireds are input, ground, and negative power. On the right you can see it tuked into the top of the 8601; it's the yellow blob just to the left of the transformer.

The original outputs on the back came with a nice label plate that just flipped over and added my own labels.

 Here's the output of the ramp, the original blanking signal, and the inverted blanking signal. You can see that the blanking signal is now inverted.  Yes, I should have kept the PNP in its linear region so that I preserved the nice ramps on the blanking signal, but it's not that critical and I was able to just throw the switch together with resistors that were just lying on the bench, literally. I have no idea what's causing the small spurs, I thought that it might have been my circuit, so I took it out, but they didn't go away. In any case, it's a blanking signal, it's hardly critical.

With blanking fixed and the jacks moved around to the front of the generator, I installed it back onto my bench ready to do some more testing. The output of the generator isn't quite according to hoyle. It looks reasonably clean on the scope, but, it appears to be low and the highest output position doesn't increase the signal at all. I suspect, as I stated earlier, my output amp has problems, but, for now, it's feeding a fairly clean and adjustable signal to the output, so, I'll proceed anyway.

My first attempt used my Boonton microwattmeter as a detector. It's old and crusty, but it works. I have no idea how accurate it is, however, as I don't have anything that is precise enough and reliable enough with which to check its calibration.  In any case, it's too slow to be useful in this context. To get a reasonable trace you have to run the sweep speed faster than the Boonton can reasonably follow.

I switched gears and grabbed an RF probe that I hacked together some time back for some reason. This is not a work of art by any means and was constructed without much thought, somewhat blindly, from an old handbook.  
The resistor tacked onto the 1/2 watt was not in the original build. After reading more detail I learned that the value of the resistor was based on the 10 megaohm input impedance of most VTVMs of the day. My scope has a one megaohm input impedance so I tacked a resistor in parallel to create the approximately correct voltage divider circuit. It helped, but I also read that these are really designed for a relatively low impedance drive circuit and I suspected that it was loading down the filter and my scope was already at its highest sensitivity. Further, it did not give a log output which would give me a better picture of the filter's response.  Finally, I never liked the housing choice for a probe, it was made to be quick and I would prefer to have an RF probe in a more probe like enclosure. So, I removed the simple circuit. Upon doing so I found a cold solder connection from the diode to ground, that might have been the cause of some of the nose, no matter, I was sticking to my plan.

I built a log detector using an MC13136, which is a receiver on a chip. Yes, it's a bit of a waste, but it's a through hole part that I have a few of which meant that I could whip it up quickly on proto-board.

The TO-92 part to the right is an LM78L05 which provides a regulated five volts for the log amp. To the right you can see a 1N4004 in series with the positive power terminal. This serves to drop the input voltage a small amount and to provide reverse polarity protection, something that might happen with such a casual power input. The two resistors at the top right are 100 ohm resistors in parallel, so, yes, this has a 50 ohm input impedance, but, it also has a wide range.

Does this yield an improvement? Yes, it does, but, it's still fiddly. At least now I can see something of a filter shape and adjusting the input and output pots does not completely kill my signal. It is not really effective at coming close to the impedance of higher impedance filters. I have one with a known impedance of 3.9k and as best as I can get with this setup is, larger than a few hundred ohms. 

My best result was with a Yaesu filter believed to have a 200 ohm impedance, my adjustment showed about 150 ohms. As for the filter that is the subject of this post, it remains a source of frustration.

What I've concluded however, is that old analaog equipment with voltage controlled sweep is not ideal for this kind of measurement. The controls themselves must interact; to get a wider image on the scope you either have to adjust the sweep, or, the X gain of the scope, either choice moves the bandpass in the image on the scope.  The precision required here is really only in two dimensions; first, you need precision in frequency, and second, you need precision in measurement of the resistors. The latter is independent of the test fixture, while the former is much more easily controlled in the digital domain.

The goal is to be able to repeat these measurements easily;  in the next installation I will move forward with a DIY simple scalar network analyzer based on the AD9850.

SmartCans Final Hardware Assembly

In getting the headphones buttoned up for presentation I ran into many small issues. In the end, what I expected would take just a couple of days took almost the entire week.

Here we can see the left side buttoned up. The small holeplug fills what was originally to be the exit point for the wiring. This presented two major issues. First, it was just ugly. Yeah, there isn't any way to say that other than it was ugly. I thought that it might give something of a borg look, I even thought about using clear heat shrink tubing so that you could see the wires. Ok, in another life I might have been an artist, but not this one. So, given that, I opted for the artistically challenged version of artistic, minimal and simple. I would stick to black heat shrink tubing where exposed and try to constrain the profile as much as possible as the spacers were already making the phones larger than they were originally.

Second, bringing the wires over the top of the circuit boards took up a significant portion of the vertical space and put too much pressure on the pc boards. Although it took a bit more effort, running them out of the top of the cups not only looked better, but allowed for much more breathing room inside the cups.

Here's the inside of the left can. The spacer is made of wood and colored with yellow stain. Yellow looks cool with black, and well, it was the only color of stain that I had in the garage. The wood is just plywood from a model shop. The wood is about 1/4" thick and serves to lift the rest of the earpiece away from the bottom half of the cup by that amount. Additionally, it serves the same role as the top half of the cup by presenting a flat surface that helps to bind the ear cushion in place. 

You can see how the cable is routed through the pcboard out of the cup and through a slot cut into the wood. The cables are connected on both ends with a 9 pin 0.2mm header. Even these are really too large, but, they are what I had on hand. The three pin 0.1 inch header to the right is the line level input which will connect to the 1/8" jack on the top half of the can. The cup gouged in the wood at the bottom is there to make space for the jack to fit.

If you look closely you can see some bright yellow felt underneath the pcboard. This is to prevent rattles.

Here it is, (almost) ready to be buttoned up. I didn't apply the heat shrink tubing until later because I needed to space it from the headband's point of view.  I say almost because this picture was taken before I realized that the cables really needed to go underneath the pcboard as shown above.

The original screws that held the two halves together were too small and I had to hunt down something that was long enough and about the right size. Fortunately, plastic is forgiving so some standard machine screws did the trick. After both sides were buttoned up.  I focused on getting the harness together for both sides. One of the things that I did early on in the assembly was to identify the pin numbers for each wire. I used a sharpie to mark each wire with the number of dots related to the pin number.

Here was an opportunity to use the "Western Union Splice" as taught to me by my seventh grade electronic's instructor, Mr Crandell. Of course, there's not really any loading stress, but you want the wires to be as small as possible. Don't forget to put on all of the heat shrink tubing first.

Although you can see the battery in this picture, the battery does not connect into the harness. The harness supplies five volts to each earcup and the battery only generates about four volts. You can see the power leads spliced into the harness, however, they go to the power supply modules visible on the headband.

 Here's a better shot of the power supply modules on the top of the headband. On the right is the charger module which takes USB power in and supplies power to charge the battery. On the right is a USB power module which takes battery voltage and converts it to five volts for USB. This module originally came with a USB connector attached. I removed the connector as it was unneeded and excessively large.

Before I put the headband on, they look like this taped up with a bit too much electrical tape, we'll work on that.  The headband is an aftermarket product that is designed as a replacement band for headphones that have a worn band. It serves a larger purpose here in that it covers the power supply components.

Here they are, buttoned up both with a cable plugged in so that they can be used like regular headphones, and without. Since they can also be wireless, it was important to make the cable removable.

The Death of a CB

A trip to the K6IS hamfest this past weekend landed me this beauty for the princely sum of $5.  I probably should have worked him on the price a bit, but, sometimes I'm just not in the mood to haggle and this was one of those moments.

Yep, that's a Sears RoadTalker 40 complete with a CB radio call sign of BDX-1676.  Now, that might be an official callsign from the FCC, or it might be some other CB related number, I really don't know. It does have the correct format for an original call sign, but I have no idea whether those numbers and letters were used by the FCC. By the late seventies, CBs came with a form that you filled out that basically had you self assign your CB call, not that anyone bothered.

More often than not with these old rigs someone has made a small addition, note the toggle switch at the top of next picture.

The switch goes down to the PLL area underneath so I assume that it was some sort of frequency mod. The biggest disappointment here was that the switch was totally dead, the handle was just flopping around. That's one switch that won't make it into my junkbox. 

Ok, but that's not why I gave up a fiver for this sweet sweet radio, nope, the reason is a bit simpler. It's because there's gold inside, sweet sweet filter gold. Ok, some of the other parts will make it into my junkbox. I always pull the driver and final transistors, the transformers, and the pots with switches. Sometimes I pull the toko cans, sometimes I don't bother. Any other crystals also get pulled, you never know when you might need som odd frequency, most of the rest goes to the recycler. 

There she is, ready to be plucked. We can see right away that she's got a useful center frequency of 11.2735 Mhz. Now to find the matching crystals, they're in there somewhere. This could be one of them right here.

As it turns out, that crystal was for 11.730. Now, that's not useless, it's perfect for a dual conversion receiver as it is 455kHz away from the filter. However, it can't be all there is because we should have USB and LSB crystals somewhere in the radio that are just a few kHz away from 11.2735. I assure you that the surgery was swift and painless.

Could this be them? As it turns out, no, these are 12.230 and 12.319 Mhz crystals that don't appear to bear any direct relationship to the 11 Mhz IF. I'm not really sure what they do in this radio either although I suspect that they have something to do with the PLL.

 A little digging and we've found the rest of the treasure hiding in the corner under some wiring

There you have it, the filter, it's LSB and USB crystals, and a bonus crystal 455 kHz away for building a dual conversion reciever with a 455 kHz IF. 

Now,  here's the catch. I don't have any impedance specs for the filter. Sometimes you get luckier and the filter either has the data printed on it, or, you can find specs online. The only reference that I have for the filter is another ham trying to sell a set just like this online. Having the schematic of the radio would allow me to at least make an educated guess, but that's not so easy either. The actual radio model number is 934.38260700, and, as near as I can tell, there are no schematics online. 

So, feel free to comment below if you have any insight about the impedance, data catalogs for TWE-FEC crystals, or a schematic for the Road Talker 934.38260700.


With an ongoing discussion on QRZ, more data has come out about this filter, however, it's still not clear what the impedance is precisely. It is the same filter used in the radio shack TRC48 as well as several other road talker, and probably radio shack, radios of the time. 

I took the time to trace out a partial schematic from the pc-board. I can't get much more than this because jumpers start to take the circuit to other unknown places.  This is not a low impedance filter. 

Microphones and Cost

In a recent QRZ post someone asked about whether Heil mics are  worth the cost?  The PR-40 was mentioned as being particularly good for its flat response and ability to handle loud sources close up.

First, the PR40 is a good dynamic microphone and compared to other large format dynamic microphones it is not excessively expensive.  IMNSHO, however, you don't gain much over lesser dynamic mics for ham radio use. But, when I say lesser dynamic mics, I don't mean the really cheap mics that come with radios, I mean lesser dynamic mics typically used by musicians such as an SM-57 or an SM-58. An inexpensive Behringer might be a decent budget choice, it might not, I haven't tried one (for music).  One thing that I do know, however, is that once you start to drop below the quality of an SM-58 in a basic vocal microphone the differences become very noticeable.  

What is WELL understood in music and voice recording is that different mics flatter different voices differently. So when people are choosing microphones there cannot be a standard answer, this is for both spoken voice and singing.  One might choose a condenser mic for a certain female voice and that same mic sounds harsh or weak on a male voice.  You guys are showing off curves as if they really mean something. The thing is, the little tiny bumps in those curves can make a difference with a particular voice. The PR40 isn't flat; it has a pronounced bump starting at just over 1.5k and extending almost to 10k. This is going to have a profound effect on how the mic sounds with a particular voice.

I've noticed this very specifically when recording with certain mics. An SM58 sounds ok, but my voice is somewhat low and also has a sharp low-mid presence. So an SM58 does not enhance what I consider to be the sweet spot in my own spoken voice. The AKG C2000B condenser, on the other hand, really emphasizes that part of my voice.  It has a warm tone that I have not been able to get with anything other than a dynamic or ribbon mic. That said, like all condensers, it picks up more background noise than I would like, but, the point here isn't to recommend condensers, per se, it's to talk about why curves don't always directly tell you how a mic is going to sound on a particular voice.

Another condenser mic that I own is the CAD M179. It is a fantastic mic for certain applications, in particular, I like to use it for M/S (mid-side) stereo recording with a Shure SM-81. It doesn't sound very good on my voice however, even worse than the SM58. It's a very flexible mic and I wouldn't hesitate to use it on a female or child's voice.

Neither of these mics retail for what would be considered "ham cheap", although both would be considered budget microphones in a studio setting. Both retail for under $400 today, the C2000B is an older design that was more expensive when it was new. The CAD can often be had for well under $150. Again, I'm not recommending either of these microphones, we're just talking about frequency response. So, let's look at their curves:

First the C2000B. It's mostly flat, it falls off below 100Hz, and there's a bump in the high frequencies starting around 5k.

And now the M179. It's flat well below 100Hz, but has several peaks beginning at about 3k.

So, looking at those two graphs, there's no way that you could predict which was going to sound better on my voice, or, in fact, your own.  You might believe that the AKG would sound better because it was more flat through the mids, but then, the Heil above has emphasis below 3k like the CAD.  Moreover, you might think that the flatness below 100Hz  in the CAD would help my low voice, but, in fact, the AKG sounds beefier, despite the roll off.

If you want to actually make an informed evaluation of mics then ignore much of what people say on ham sites, at least up to the point that the mic enters the radio. There is as much hearsay and nonsense as anything legitimate. Look for home recording sites and "spoken voice" artists sites to get the basic understanding of how a microphone works for a particular voice. However, you really have to know how it sounds on your own voice. Once you have that part down, then tailoring the EQ to work well within the constraints of ham radio becomes a separate issue and hams tend to have that side of things down a bit better.

There are a lot of good mics in the price range of the PR40 and some might be better but I suspect that hams wouldn't really try them because Heil is a well known and respected brand in the amateur community.  For example, there are well known solutions that tend to go well with male spoken voice, the Sure SM7B comes to mind here. Basically, one things that hams get right is that the mics made famous for broadcast often have some features that flatter male voices. Note: the SM7B requires a stout preamp.

Here's the response curve for the SM7B.  Note that the LF response extends to below 100Hz.

A poor mans SM-7 is to take an SM-57 and remove the transformer. You now have to be careful that DC doesn't go across the element but that's usually not a problem for ham applications. The biggest risk for musicians is if the mic gets confused with a standard SM57 it could get damaged.

Here's the curve for the stock SM57. Note that it is relatively flat down to about 175 Hz and has a midrange bump starting about about 3k. the mod described above reduces the midrange bump and also extends the low end frequency response.

I'll post more on this later but the essence of the mod is that you need to heat the wax in the lower half of the mic until it becomes soft so that you can remove the transformer. Then you simply solder the capsule to  the XLR connector.

For simple practicality, I think that it's rather difficult to do better than an SM58. As I said earlier, the SM58 doesn't flatter my voice in the low register, but, I'm not sure how much that matters over the radio. It certainly gets the job done and I remember getting one for the first time. It blew away the cheap mics that it replaced.

The SM58 has a built in windscreen and pop filter, so it's simple and practical. It has slightly better low end response and a less peaked mid bump than the SM57.

Of course, the SM57, or SM58 doesn't look as "pro" as some of the other offerings and that might have an impact on the perception of sound quality.

So, is the Heil worth the money? That's up to you, but, let's clear a few things up. First, it's not expensive for a studio quality dynamic microphone. Comparable mics lie the SM7B are priced similarly. Second, expensive doesn't necessarily mean better for a given purpose. If you can't hear the difference on your voice, then that's money wasted. Third, frequency response curves don't tell the entire story. These curves look more similar than they do different, at least in any way that one could predict that a given mic would be better. The CAD is more flat in the low end, yet that doesn't do much for my voice. If anything, it's the absence of any midrange boost in the AKG that is what best defines a mic for my voice, yet, there are other mics with a similar curve that do not sound good. You have to listen to what your voice sounds like on a specific microphone. Subtle differences in response, even in areas that appear flat, may have enough of an impact on your voice that the difference matters to you.

Well, what mics do you use?  Do you have any surprises to share? Post your comments below. 

Thursday, May 14, 2015

Even Simplified, the SmartCans are Going to be Tight

As of the weekend there was still a lot of work to do to pack the Edison into a set of headphones. The Edison is small, but until you've tried to build a circuit with real wires into a headphone, it's hard to appreciate how big things really are.

For the first prototype, I've ditched the external amplifier and moved the power supply into the headband. This will allow me to use a single battery and charge via USB. That way I'll actually be able to use the project in my day to day listening activities and will get a  real sense of how it performs over time.

Here's a shot of each ear to get a sense of size along with some test wires. I still have to hook up the usb ports.

Tuesday, May 12, 2015

That Elusive First Contact

I first posted this story to eHam about ten years ago after getting licensed as KC8YGZ.  Since eHam doesn't allow comments on closed articles, and, since I am the author, I'm going to repost it here. 

As published on eHam.com in September of 2003

I've been involved in ham radio in one way or another since my early teens. I used to go to the local club meetings of the Spokane "Dial Twisters." As a teen, however, I was unable to learn the Morse code. I tried tapes but would memorize the tapes before leaning enough of the code. In retrospect, what I needed was someone to practice with, but nobody offered, and I didn't know at the time to ask.
Fast-forward to 1983 and my first duty assignment in California. A newfound friend with similar interests told me of a local class for novices and invited me to go. About three weeks later I passed the Morse code test. (I had someone to practice with), and the only major hurdle was overcome. I don't think I studied at all for the written but I aced it easily; after all, I'd been reading the handbook for at least five years!

I don't remember how long it took, but sometime later I get the call KB6AOL; yeah, it would be funny to have that call today. At any rate, at the time I didn't own a radio, and while I had access to the club station, I had other things on my mind so I left California without making a single contact.
When I went home on leave I spent most of the month building a forty meter QRP transceiver from a combination of articles in QST and the handbook. I think I used the tuna tin two transmitter and one of the mountaineer series receivers along with various other things.

I strung up some wire, did a quick review of the code, and called CQ a few times, but, as might be expected when one combines no experience, 200 milliwatts, a direct conversion receiver, and a substandard antenna in an urban environment, no real results were obtained. The transceiver eventually became parts for other, more pressing, projects. I still have the audio filter though; it's in my SW receiver.

After returning from Germany I bought an Eico 753 at a yard sale and tried hooking up some wire antennas, but my code was too rusty and my interests were being pulled strongly in other directions. KB6AOL had never made a contact; I let my ticket lapse....

....until now.

A recent need for a kindler gentler morning wakeup led me to construct a one-transistor FM broadcast transmitter so my alarm clock would play streaming audio instead of nasty broadcast FM. That project woke up something else, however, the thrill I get from building RF projects.
A short diversion into part 15 experiments was interrupted by the realization that I could just get a new ham ticket. A few phone calls later I was scheduled to take elements one, two, and three the following Saturday.

Computers make studying Morse code a LOT easier, I managed to learn enough in that week to pass the code test both ways, i.e. 25+ straight copy and seven or more questions right. The only thing necessary for me to pass the other elements was read every question, yes, all 900 of them, once.
Less than a week later, on the day of the power outage no less, my call showed up in the database, KC8YGZ, that's a mouthful no matter what mode you say it in. The following day, my FT817 showed up at the door. By the evening, the power was restored, the batteries were charging and I was futzing with some hastily made dipoles. The following afternoon, I chased down the mailman to get my LDG Z11 kit, built it that evening and by 10pm Saturday night I was sending out a signal on 40 meters.

....sort of....

Several hours later I was hoarse, metaphorically that is; my CQs went unanswered. To make matters worse, I'd call CQ only to hear someone else calling CQ on the same frequency. Much faster than me of course; no point in trying to answer. They didn't hear my CQ in the first place, and although I knew they were calling CQ, I sure couldn't copy the call.

Well, of course, nobody could hear me. After all, I only have five Watts, and my antennas are substandard. This calls for (drum roll please) ANTENNA EXPERIMENTATION!!! Well, for the next few days I tried dipoles, long wires, the rain gutter, verticals made of this that and the other thing, I even loaded up the window frames. I tried almost every stealth antenna trick I could find on the net. I live in a first floor apartment, so I must use a stealth technique. To be clear, I am hearing people, and in fact, there hasn't been a significant variation in my ability to receive. The full length, but bent, forty meter dipole seems to work about as well as anything I can get away with putting up outside, at least on receive.

After much reading about the challenges and successes of others I settled on a couple of antennas that "should" work, built them carefully enough so that they would work without the tuner on at least some portion of the band and sat down to focus on making a contact.
Well, let me tell ya, after you call CQ and your own call about seven hundred and fifty times you get really bored and start to send too fast. Yes I tried listening for others calling CQ, but someone would always beat me to answering, or, more often, they were sending too fast for me.
I felt it best to hang out on the novice bands as that should be where slow CW ought to be tolerated, and besides, I'm trying to live that missed novice experience.

So I'm sending my CQ in a very blasé manner and out of nowhere, holy cow, someone starts to transmit as soon as I stop and it sounds like they might be talking to me. I copy "something something somethng DE WJ0C WJ0C something." I wasn't sure, was he talking to me? All of a sudden I got very very nervous, and simply sent WJ0C WJ0C DE KC8YGZ KC8YGZ. At least I think that's what I sent; I might have made some mistakes. After I stop, here comes a flood of code. I started copying, but it's too fast; I get flustered, Lost. I got something of the QTH, but didn't here my own call anywhere. He stops, was he talking to me; I still don't know. I copied hardly anything of what he sent and if he wasn't talking to me, well, I didn't know what to send, I panicked, froze, right there. Yes, I'm a grown man, and yes I panicked about something so trivial. Anyway, I waited a minute for something else and then just started calling CQ again, this time much more slowly.
I tried for several more hours moving between 7110 and around 7040, but no more contacts or "possible contacts" where had.

Jim, if you were talking to me, I apologize for not giving you much of a conversation.
It's been almost thirty years since I first became excited about ham radio, and I still haven't made that first HF contact. I have no intentions of giving up. I might try building a fifty wattish tube PA, or, what the heck, just getting my hands on a more powerful transmitter. But ultimately, I want to succeed with low power because building is what I enjoy, and low power stuff is far more approachable.

So, if you hear my anemic CQ on 7110, could you perhaps send a quick email to KC8YGZ@planetp.org saying "Daryl, I heard your CQ from [fill in your QTH]". At least that way I'd have some idea of how far my signal was reaching. The way it stands now, it looks like I might get my extra ticket before I ever make a single HF contact. I'll be taking element four in September.
You can be sure I'll be asking for a systematic call change, at least that way if Jim was talking to me, I might get a second chance.


In case you're wondering, I didn't retire KC8YGZ contactless. I posted this followup comment a few days later on Sep 13. I'm copying it here, so that I have my own record of that first contact.


Well, looks like I'm not going to retire KC8YGZ contactless. This evening I was able to complete, albiet barely, a QSO with AB9HT, Ray, in Collinsville, IL. This means I was able to cover a distance of 498 miles with 5 watts into the rain gutter. That's about a hundred miles per watt. Now I have a goal, and no desire for more power.

thanks ray

(soon to be something shorter) 


One of the things that I enjoy about amateur radio today is the ease with which one can test their station's ability using digital modes. I remember back then, trying to listen for my CQ using remote web listening stations, it wasn't too effective. At any rate, I hope that you enjoyed the story, feel free to comment below. 

One of Two, What to do?

Ok, hopefully I tricked you into opening the blog post with that provocative title. Now that you're here, I have two of these pulled from some old military equipment. I'm holding on to then for that perfect project that requires two matched 500hz filters. At one point I was concerned about the center frequency and finding a crystal, there wasn't one in the unit. However, these days it's cheap enough to generate signals at any frequency that I'm not that concerned.

Ok, enough chit chat, here she is!

Front view with a full origin story.

Bottom view, so nice that they labeled the ins and outs.

Top View, all the pertinents, right there on the can!
If you have a suggestion, by all means add it to the comments below. I'm all ears, literally, my mother used to caution me to stand sideways in strong winds, she was afraid I'd catch a gust and sail away,  and figuratively, RO means read only since I spend more time building than operating.