Science Fiction Bucket List

The Hugo Awards are a set of literary awards given annually for the best science fiction and fantasy writing. The awards are named after Hugo Gernsback, the founder of the science fiction magazine Amazing Stories. They been awarded annually since 1953.

Prizes are awarded in a number of categories, including best novel.

The Retrospective Hugo Awards, or Retro Hugos, were added in the mid-1990s and are awarded for works published prior to the start of the annual awards.

To date, 70 Hugos have been awarded for best novel, including six retro Hugos.

I have read a number of the Hugo award winning novels over the years, and all of my favourite science fiction authors have won at least one award. A check of my science fiction collection identified nine Hugo award winning novels in my bookcase.

I have been wanting to expand my reading of science fiction to include more authors, particularly some more modern novels. The idea occurred to me to set as a goal to read all of the Hugo award winning novels, starting with the first Retro Hugo in 1939, up to the current (2018) winner. I'm going to make an attempt at this, starting with the earliest novels and moving to more recent ones. Ideally, I will reread some novels that I have already read, if it has been some years since I did so.

This may take some time - possibly years - and the list of winning novels will continue to grow as a new one is awarded each year (there will likely be some more retro Hugos awarded as well).

I plan to write a short review of each novel here on this blog.

I now have on order several of the early novels, and a few of them I already own, so I hope to start the first reviews within the next few weeks. I hope some of you will follow my progress, and maybe add your comments if you have read the same novels.

Effective YouTube Videos

I don't consider myself an expert by any means, but after making over 100 YouTube videos I can think of a few tips that will help improve the quality and effectiveness of videos that you might want to make and help you avoid some "newbie mistakes".


You don't need a professional camera, but try to use something better than a smart phone. A digital camera that supports video is one good relatively low-cost option.

Use a tripod! A handheld camera will not cut it. You can buy an inexpensive camera tripod or even improvise something. If you need to shoot while moving, explore low cost camera gimbals.

Use an external microphone. This will greatly improve the sound quality. Also try to record the video in a quiet place (as much as possible) to avoid extraneous sounds like telephones, clocks, pets, people talking, etc.

Edit the video! Make use of some (free) video editing software to edit out mistakes, remove silent portions of the video, and add some basic titles and effects. There can be a bit of a learning curve here, but it can greatly improve how watchable the videos are, and it can be fun.

Use as much light as you can. If you don't have professional lighting, see what you can improvise by adding additional lights over what would normally be in the room.

You may prefer to read from a script, or to make the video impromptu. Either is fine - whatever best fits your personal style. But at least have an overall plan and structure to the video, what you want to say, and what you want to do or show.

Change camera angles often. Try to make use of motion, i.e. don't just show something, but move or operate it.

When uploading to YouTube, give your video a descriptive title, a good description, and add keywords. Fill out other information like language, recording date, etc.

Keep the video short and to the point. You will lose viewers if it goes much beyond 10 or 15 minutes. Edit out silence and don't pad it out with an overly long introduction or background information. Consider splitting a video up into multiple parts if there is a logical way to do so.

The Octopus Curve Tracer

I recently put together an interesting little piece of test equipment. It is a simple curve tracer, sometimes called a V/I curve tracer or an Octopus curve tracer (because it has eight wires coming out of it).

It is used for testing electronic components and circuitry, and works in conjunction with an oscilloscope in X-Y mode (where the X and Y axes indicate the voltages on each channel and no time base is involved).

The basic idea is to apply a small (typically 1 volt) AC voltage across the unit under test (UUT). The voltage across the UUT is connected to the oscilloscope's X or horizontal axis. The current through the UUT is sampled across a resistor and applied to the scope's Y or vertical axis. The pattern on the oscilloscope indicates the current/voltage characteristics of the UUT on the display. The pattern, sometimes called a signature, gives information about the UUT.

For example, An open circuit, with voltage but no current, will appear as a horizontal line (the pictures here were taken using an oscilloscope and the unit I built):

A short circuit, with current but no voltage, appears as a vertical line:

A resistor will show a diagonal line, with the angle varying depending on the resistance:

Capacitors and inductors are more interesting. They will cause a phase shift between the current and voltage, resulting in a circle or ellipse whose width depends on the value of capacitance or inductance. Here is a capacitor:

A combination of resistance, capacitance, or inductance will show both a line and a ellipse.

A diode (or the semiconductor junction between two leads of a transistor) will show the characteristic "knee curve" of a diode where it conducts in only one direction once the forward voltage is reached (recall that we are applying an AC voltage so we can see both forward and reverse behavior):

The tester is most often used to test components. It can be used in-circuit, provided that the unit under test is powered off.

In the simplest version of the tester the AC voltage is fixed and derived from the AC line using a transformer. I built a version based on the QEX article listed later under References which provides three selectable voltage ranges of 1 volt, 5 volts, and 10 volts RMS. This allows devices like Zener diodes to be tested that require higher voltages in order to see them conduct in the forward direction. In all cases the current is limited to about 1 mA to prevent damage to the device or tester.

The tester is generally safe for testing all components, with a couple of exceptions. One is electrolytic capacitors, which shouldn't have a reverse voltage applied to them (although I doubt that a few seconds applied to the tester would do any permanent damage). Also LEDs have a relatively low peak inverse voltage rating (typically 4 to 5 volts) that could be exceeded on the higher ranges.

I build my unit based on the design described in the 2017 QEX article. As mentioned, this design incorporates three voltage ranges. It uses trimmer pots to allow the output voltages and short circuit currents to be adjusted. I modified the circuit slightly, adding a fuse and using the range switch to control power as well. I adjusted the resistor values to work with my power transformer, aiming for for 1, 5, and 10 volt RMS ranges and 1 mA maximum current.

Parts came from my junk box as well as some low cost new parts ordered from eBay sellers in China. The transformer was an approximately 12 volt secondary unit found in my junk box. The case, rotary switch, and most of the connectors were new parts, including some low cost test leads with banana jacks and alligator clips.

I built the circuitry "ugly style" on a piece of copper clad PCB using MeSquares from QRPme.com. It was then wired to the switches and connectors in the case using point to point wiring.

The unit is calibrated by connecting an AC voltmeter to the red and black leads and adjusting the appropriate pots for the desired open circuit voltage on each range. Then an AC current meter is connected across the leads and the current limiting pots are adjusted for a current of 1 mA on each range,

The summary of how to use the unit is the following:

1. Set to desired range: 1V for semiconductors, 5V or 10V for Zeners.
2. Attach leads to oscilloscope scope and put it in X-Y mode.
3. With open circuit, adjust the scope for a horizontal line the full width of the display.
4. Short the test leads and adjust the scope for a vertical line the full height of display.
5. Connect the component or circuit under test across the red and black leads (with power off) and observe the display.
6. If changing ranges, repeat steps 3 and 4.

Overall it looks quite nice and I plan to keep it handy on the bench. If you have an oscilloscope that supports X-Y mode, I would encourage you to try you hand at building a unit.

References

1. "The Octopus: An Overall Component Tester for In-Circuit Troubleshooting", David L. Ludlow W7QHX, QST magazine, July 1975.
2. "Improve Performance of Your Octopus V/I Curve Tracer Using a Single Voltage Transformer", Paulo Renato F. Perreira PY3PR, QEX magazine, May/June 2017.

Commercial products based on this technique exist. The "Huntron Tracker" is one such unit. Semiconductor curve tracers are also similar but more sophisticated. Some oscilloscopes also offer a curve tracer function built in with a "component test" mode.

Rebuilding The Heathit AT-1 Transmitter - Testing and Wrapup

I did further testing of the restored unit, measuring voltages against the manual, and they all looked okay.

The unit was speced at operating from 105 to 125 VAC. At the time it was released line voltages in North America tended to be lower than today (typical 120 VAC or more now). For testing purposes I found that an input voltage of 117 VAC gave heater (6.3 VAC) and B+ voltages that were close to what was listed in the manual, so I did my testing with a Variac set to that level.

I measured the RF output on each band both with a rather inaccurate SWR/power meter and by measuring the peak to peak output voltage on an oscilloscope across a 50 Ohm dummy load.

    80M: 13 Watts
    40M: 12 Watts
    20M:6.3 Watts
    10M: 1 Watt

Power on 10 meter is quite low, but is apparently normal as the output tube has very low gain at the higher frequency. I captured the output on different bands on my oscilloscope:

Since the power supply is not regulated, there is quite a drop in the B+ on key down, from 512 to 430 volts. Note that there is also 139 VDC at the code key contacts, so you want to avoid touching them!

Here is the oscilloscope output of keying:

And using the spectrum analyzer mode of my Rigol scope:

It is interesting compare some of circuitry before:

and after restoration:

This project was a lot of fun - I got to recreate the experience of building from a kit. I was also fascinating think that someone built this in the late 50s or early 60s and obviously used it quite heavily over the years.

I will have to try it on the air once I get an new antenna up. The power level qualifies it as a QRP rig.

I'm still looking to find the VF-1 matching VFO if I can get one at a reasonable price.

Rebuilding The Heathit AT-1 Transmitter - It's Alive!

Initial powerup tests are good and indicate that it is producing output on all four bands. I powered is up slowly with a Variac and then did some testing with an input voltage of about 110 VAC. I'm seeing output on all four bands, close to 10 Watts of output power depending on the band.

I find it is easier to adjust the driver and output controls by looking for maximum power output rather than the built in meter (the usual procedure is to adjust the driver control for a dip in the grid current and then adjust the output control for a peak in plate current - except for 80 meters where the drive
input is not tuned). The meter is an old iron vane type that is not damped and bounces all over the place until it stabilizes - which is not very good as you need to quickly adjust the controls to minimize the chances of damaging the output tube.

I still need to make some more voltage and power output measurements and look at the output waveform while keying.

I'm still also waiting for some octal plugs - one is used for an optional modulator (and needs to short two pins when not present) and one is for an optional VFO.

Heathkit sold the VF-1 VFO or Variable Frequency Oscillator that allowed it to transmitt at frequencies set by the VFO rather than fixed with crystals. I hope to acquire one of these some day - they show up on eBay quite often.

The unit could also transmit using AM voice, with an external modulator. Heathkit never offered a modulator kit, but various circuits were published at the time and in fact Heathkit published a suggested circuit in their 1955 sales flyer. It would make for an interesting project to build one - it used 5 tubes (one dual), making it a little more complex than the AT-1 transmitter.

Rebuilding The Heathit AT-1 Transmitter - Coil Wiring

The last stage of assembly is the wiring of the oscillator and bandswitch coils on the top of the chassis. Most of this is done with heavy solid wire. I used #14 solid copper house wire with the insulation removed. The oscillator coil, four bandswitch coils, two tuning capacitors, and bandswitches are all connected. It is important to follow the order shown in the manual and double check against making wiring errors that will be hard to change later during assembly.

Soldering the heavy wire is beyond the heat capacity of my small Weller soldering station. I dug out my old 140 Watt (also Weller) soldering gun and it was ideal for the job.

I am quite pleased with the results, expecially when comparing it to the photos I took of the original assembly. The last step is to connect the power cord.

I am now ready to power up and test the unit, after carefully checking the wiring one last time.

Rebuilding The Heathit AT-1 Transmitter - Final Amplifier Tube Wiring

I finished up the next set of assembly instructions  - the wiring around the final amplifier tube.

The last toroid is another large one that is too heavy to stand in the air by its leads. so I sat it on the chassis. As this has some high voltage (close to 1000 volts), I wrapped it in electrical tape to better insulate it from the chassis.

Next up is the assembly of the coils, much of which will use heavy bus wire and be on the top of the chassis.