1. HF Station Systems Engineering
Part 1 of 2: Planning and DESIGN
by Drew Vonada-Smith K3PA
1 Dec 2017, All rights reserved

2. Systems Engineering? Do we need it?
This looks simple enough to me.
HF Transceiver
Dipole
Key
Mic

3. Do we need it? I’d like a better station. It’s still fairly simple.
HF Transceiver
Dipole
Key
Mic
Amplifier
Triband Yagi
Switch
Computer
Digital Interface
Rotator

4. Do we need it?
I’d love a good contest station. Single Op Two Radio (SO2R) sounds fun!
HF Transceiver 1
80M 4 Square
Paddle
Mic
Amplifier 1
40M Yagi
Switch
Computer
Digital Interface
20M Yagi
HF Transceiver 2
Amplifier 2
Keyer
DVK
160M Vertical
15M Yagi
10M Yagi
RX Ants
Band Filters
Panadapter
Rotator
Ø Control

5. Do we need it? Yikes! Maybe we should think this through?
Panadapter
160M Vertical
80M 4 Square
40M Yagi
20M Yagi
DVK
Computer
Digital Interface
Ø Control
Rotator
Rotator
Keyer
Paddle
RX Ants
20M Yagi
HF Transceiver 1
Amplifier 1
Band Filters
Rotator
Mic
Switch
HF Transceiver 2
Amplifier 2
10M Yagi
15M Yagi
Band Filters
Rotator
Rotator

6. Hell yes, we need it! What are some of the issues we face?
This is a lot of complexity to maintain.
This is a lot for the operator to set and keep track of. Distracting!
There are a lot of connections here. How do we cable it all?
How do I choose all this equipment?
Can I even fit it all on the desk and reach the controls?

7. How do we start? What are some of the issues we face?
This is a lot of complexity to maintain!
It sure is. Let’s think it through, design it, and document it.
There are a lot of connections here. How do we cable it all?
Design it. Label it. Lay it out neatly.
How do I choose all this equipment?
Learn which specifications matter, and which do not.
What about antennas?
A major topic! Let’s discuss the basics.
This is a lot for the operator to set and keep track of. Distracting!
You want the operator focused on making QSOs, not the station. Automate!
Can I even fit it all on the desk and reach the controls?
Put the most critical devices within reach. Automate the rest, or bring to a hub.

8. Design This is a lot of complexity to maintain!
It sure is. Let’s think it through, design it, and document it.
You are going to forget later. Draw diagrams. Visio is nice!
Computer port configurations get complex. Write them down.
Design, document, and implement. Don’t implement first. Don’t document last.
Simple block diagrams are a good starting point.
Keep copies of configuration files, or take pictures of setup screens. You WILL need them.

9. Design There are a lot of connections here. How do we cable it all?
Design it. Label it. Lay it out neatly.
Buy a P Touch labeler. Label both ends of *every* cable.
Use good cable. LMR240 is flexible nice for shack RF interconnections.
Use good connectors. *GOOD* PL-259 crimp types are very reliable.
Check tightness twice. Don’t forget the PL-259 tooth alignment problem!
Standardize on a control signal connector. I like 9 pin D (DE9) connectors. Use the capture screws!
Have a permanently mounted power strip with plenty of spare outlets
Consider a cable raceway, cable tie anchors, or some method of neatening things.

10. Equipment Selection How do I choose all this equipment?
For your transceiver(s), learn which specifications matter, and which do not.
Every serious transceiver made since the 1970s probably has sufficient sensitivity and (SSB) selectivity.
Yes, most transceivers are not up to the job for use on large antennas or for SO2R service.
Why?
Poor overall dynamic range (basic design issue)
Poor close in dynamic range (roofing filters)
Excessive phase noise (synthesizer)
Bad AGC characteristics (designers who don’t operate)
Dirty transmitter, either poor IMD (SSB) or key clicks (CW) (no marketing demand)
CW is a more critical application for the best transceivers, due to the nature of SSB signals

11. Equipment Selection How do I choose all this equipment?
How do I learn more about specifications that matter?
The “Sherwood List” is a good guide for receiver performance.
But it isn’t gospel. Use it as a guide, and understand it.
So, what receivers seem the best? Some currently offered proven winners are:
Elecraft – K3 & K3S. Also has one of the cleanest transmitters.
Yaesu – FTDX5000.
Icom – soon is not bad for relatively low cost, perhaps not SO2R.
Kenwood – TS-990 & TS TS-590 is a particular bargain!
Flex – 6500, 6700 and others. Very different approach.
TenTec – Orion & Orion II
Many other older radios. Ask your local contester!

12. Equipment Selection How do I choose all this equipment?
For your peripheral equipment, look at the big picture
Buying the “best in class” item for each function is not always the best approach.
Consider how the devices interconnect and play together. A family line can have advantages.
Can the various devices communicate on a buss? This may eliminate a lot of connections.
Does the company have a history of stability? You are going to need driver support for a long time.
When you have to change configuration, can it be done in software? Or will it need to be re-cabled?
…more later

13. Antennas What about Antennas?
Antenna Design and selection is a topic worthy of its own presentation, but some basic design of an approach can be addressed here.
How is antenna switching to be arranged?
How many antennas will you have?
How high should the antennas be?
What feedline should be selected? What connectors should be used?
If you need multiple bands at once (SO2R), how will you accomplish this?

14. Antennas What about Antennas? How is antenna switching to be arranged?
Method 1: Run every antenna feedline to the shack, and switch them there
This is the most flexible method. All connection schemes can be changed later.
All switching equipment is inside and protected from the weather
All those cable runs can be expensive!
If you add another antenna, you may will have to run (and bury?) another cable
Dipole
Yagi
Wall
Antenna Switch
Yagi
Yagi
Coax
Vert

15. Antennas What about Antennas? How is antenna switching to be arranged?
Method 2: Switch the antennas at the source, and run one or feedlines to the shack
You must carefully think through what you will need
Fewer cables will reduce cost, or make more expensive hardline feasible
You can add antennas later, within the capability of your switch
Waterproofing of the switching equipment will be important
Both methods have their place!
Dipole
Yagi
Wall
Antenna Switch
Control Signals
Yagi
Yagi
Coax
Vert

16. Antennas What about Antennas? How many antennas will you have?
What can you afford and fit on your lot? I recommend somewhere between one and infinity!
A multiband dipole can make plenty of contacts
A very effective compromise is a tribander on upper bands plus dipoles on 40M and 80M
Modern interlaced (non-trap) multiband Yagis can be almost as effective as mono band beams
If you need every band (i.e. WARC), a Log Periodic beam can be a good compromise
A Yagi on 40 meters is a great upgrade, if you have the room and height needed
Verticals will generally outperform low horizontal antennas for DX on the low bands
A four square array is a great step up from a vertical and can be built inexpensively
Big stations use Yagis on every band 10M through 40M, and a four square on 80M
Really big stations use more than one Yagi per band, stacked, or fixed on prime locations
160M has unique requirements. An Inverted-L is a great compromise performer. Verticals rule!
Consider dedicated receive antennas for 80 and 160 meters

17. Antennas What about Antennas? How high should the antennas be?
As high as you can! Not always true, but a pretty effective guideline for most of us.
Rohn 25 and similar towers can be pretty cheap, and often available for sweat equity.
Low horizontal antennas are not the best DX performers. A good rule of thumb is ½ wavelength, minimum.
If you cannot raise your horizontal wire or beam to ½ wave height, consider a vertical
If you have lots of really high Yagis, and no stacks, consider adding a low Yagi
Some ideal height ranges for dipoles and Yagis are:
40M – above 60 ft ft. is far better. Otherwise, go vertical.
20M – above 35 ft. 65 to 130 ft. is ideal.
15 and 10M – above 25 ft. 50 to 100 ft. is ideal.
For big spenders, using a stack can get you the best of low and high heights!

18. Antennas What about Antennas?
What feedline should be selected? What connectors should be used?
Semi rigid coax (a.k.a. “hardline” or “Heliax”) is always your best choice where feasible
½ and ¾ inch sizes are often available surplus
There is not much need for sizes above ¾”, except VHF/UHF and extremely long runs
Rigid aluminum 75 ohm cable can sometimes be found nearly free. The 75 ohm rating is no big deal.
Hard line cables normally use “Type N” connectors, often available surplus. They can be easily reused.
For flexible rotor loops, Davis RF “Bury-Flex” or other 0.400” RG8/RG213 type coax is suitable
Crank up towers will also require flexible coax. Bury Flex or LMR400 is flexible enough for this.
LMR400 Superflex is NOT RECOMMENDED for outdoor use
PL-259 “UHF” connectors are typical for coax. There is no electrical superiority of “N” connectors below UHF.
Quality modern crimp connectors are reliable when applied with proper tools. Some still do not like them. I do.
Hard line can be direct buried. Coax varies widely, some types can be buried. Many can not.

19. Antennas What about Antennas?
If you need multiple bands at once (SO2R), how will you accomplish this?
Antenna switching needs to accommodate this. A “8 x 2” switch is a common choice.
Remote antenna switching will require at least two runs to the shack, one for each radio.
Output of Transmitter X into Receiver Y must be limited, both for damage and good RX performance.
Such isolation can be achieved by antenna spacing, band filters, and coax stubs.
Antenna isolation is normally not sufficient, especially at high power
Multiband Yagis can be used on more than one band simultaneously using a Triplexer. Be careful!
Band switched low power band filters can be placed between each transceiver and amplifier
For this case, coax stubs can be added to improve harmonic interference
Or, high power band filters can be placed on each single band antenna
Front end protection for receivers is advised to avoid expensive mistakes
There is much, much more to this topic!

20. Automation of Controls
The operator should be focused on making QSOs, not running the station. Automate!
What can be automated?
For General Use
Antenna selection
Amplifier tuning
Logging
Antenna rotation
For Contests
Sending CW
Voice messages
For SO2R
Which radio is connected to the headphones, mic, keyer, digital interface
Band filter selection

21. Automation of Controls
What can be automated?
Antenna Selection & Band Filter Selection
One of the easiest and most helpful upgrades for stations with multiple antennas
Use with a remote antenna switch, located inside or outside
Most transceivers have a band selection output. BCD, Analog V, or CI-V
An inexpensive hardware interface can be used with Yaesu, Elecraft, Icom radios
More complex devices can control multiple devices like band filters and sequencers
Programmable devices can control multiple antennas per band, and change configuration via software
Consider solutions by microHAM (Station Master), 4O3A (Antenna Genius), and Hamation (BandMaster)

22. Automation of Controls
What can be automated?
Amplifier tuning
Expensive, but very helpful
Vacuum tube amps are complex and motor driven. Cost > $ ex. ACOM 2000, Alpha 9500
Solid state amps use relays for band switching and use broadband output circuitry. Many available.
Both have advantages and disadvantages
Solid state amps at less than legal limit are becoming affordable W is still expensive.
Features to consider: Power? Duty cycle? 6M? QSK? Remote control head?

23. Automation of Controls
What can be automated?
Logging
For contesting, consider N1MM, WinTest, or WriteLog
For everyday use, more choices than you can name!
Most modern products integrate transceiver control, USB or serial
Consider LOTW upload, DXCC tracking, Packet Cluster features
There is no one best solution for everyone

24. Automation of Controls
What can be automated?
Antenna Rotation
Computer interfaced rotators permit automated or manual logger control; one less thing to reach for!
Hygain and other rotator OEMs offer serial or USB interfaced rotator control boxes
Automation can also be added to popular manual control boxes
For flexibility, consider a universal control box that works with any rotator. Green Heron rules this roost.

25. Automation of Controls
What can be automated?
Sending CW
A simple transistor interface can do the job
A Winkey interface is inexpensive and eliminates PC timing issues
Voice messages
A simple transformer interface can do the job
Sending RTTY
Both FSK and AFSK options have their advantages
FSK interface is similar to CW
AFSK interface is similar to SSB and also useful for other digital modes
Commercial products integrate these functions and others
Both manual and programmable computer based devices are available

26. Automation of Controls
What can be automated?
Which radio is connected to the headphones, mic, keyer, digital interface
SO2R products can switch TX interfaces and RX output between two transceivers
Serious products are fully programmable and support advanced switching modes
Consider solutions from microHAM (MK2R+, u2R) and 4O3A (Interface Genius)

27. Centralization of Controls
Can I even fit it all on the desk and reach the controls?
Put the most critical devices within reach. Automate the rest, or bring to the PC.
Keep transceivers within easy reach. It should be comfy to tune all weekend.
Keep key paddles at comfortable arms length. Consider headset mics
Place automated amps, switches, and rotators out of the way
Route everything you can through the PC so your logger can control it
For Elecraft, consider the remote tuning pod (K-Pod)
Xkeys or another macro key solution can be very helpful

28. Centralization of Controls
Xkeys or another macro key solution can be very helpful
The author’s Xkey bar. No control keys need to be memorized for major contest functions.
One key press can:
Turn the rotator to the bearing for the station entered in the log
Move to the CQ frequency
Move to the last Search & Pounce frequency
Change RX and TX to the second radio
Swap frequencies of the two radios
Listen to radio #2 while radio #1 is calling CQ
Change to alternating CQs on two bands
Listen to both radios in stereo
...and more

29. Centralization of Controls
An neat SO2R Layout at 4O3A!

30. Centralization of Controls
The Author’s Station – Small But Efficient

31. Questions?
Any Questions?

32. Thank you for your interest!
Conclusion
Thank you for your interest!