Sights from the New England Tech Trek (NETT) at NEAR-Fest

We have been working on project to scale our open house activities to provide an opportunity to learn about Amatuer Radio and to showcase some of the modern, “hi-tech” aspects of the Amatuer Radio Service. This project was debuted at the NETT event at NEAR-Fest. We used our Portable Satellite Station, Remote Operating Gateway, and our Mobile HF Stations as part of this activity. There might be some ideas here that you can use to create an exciting operating activity at you local club or Ham Fest.

Source: Sights from the New England Tech Trek (NETT) at NEAR-Fest

SSTV Images from the ISS – Cosmonautics Day Event

The Amatuer Radio gear on the International Space Station (ISS) supports digital and SSTV modes as well as FM voice communications. The astronauts onboard periodically fire up the SSTV system and transmit images to commemorate milestones in space travel. We recently received a set of 12 images from such an event which commemorated Cosmonautics Day. You can read more about how this is done and view the images via the link below.

Source: SSTV Images from the ISS – Cosmonautics Day Event – Nashua Area Radio Society

Upgrading our 2.0 Satellite Station for ARISS Contacts

We have been working with Hudson Memorial School near Nashua, NH to prepare for a possible ISS crew contact. The ARISS folks work with schools and their Ham Radio helpers to prepare for these contacts. ARISS provides recommendations for ground station equipment to help ensure a good experience for the students. The ground station recommendations provide a solid set of specifications to support communications with the ISS on the 2m band. The recommendations include things such as:

  • A requirement to build both a primary and a backup ground station
  • Radio and power specifications (a 200W amp is recommended)
  • Antenna specifications including recommendations to provide for switchable LHCP and RHCP
  • Computer controlled azimuth/elevation positioning of antennas to track the ISS
  • Use of a receive preamplifier at the antenna
Portable Satellite Station 3.0 Antenna System

Portable Satellite Station 3.0 Antenna System

We have recently completed construction and testing of our Portable Satellite Station 3.0 which was built specifically to meet the primary station requirements for our ISS contact.

Our plan is to add some upgrades to our Portable Satellite Station 2.0 to create a Portable 2.1 Station which meets the backup station requirements. These upgrades will include:

All of the equipment needed to upgrade our 2.0 Portable Station to 2.1 is either here or will arrive shortly. Here’s some more information on the planned equipment.

Icom IC-910H Transceiver

Icom IC-910H Transceiver

The Icom IC-910H was Icom’s flagship Transceiver for Satellite work before the IC-9100 was released. It’s a very nice satellite radio! Dave, K1DLM graciously lent us his IC-910H for use in our backup station.

Green Heron RT-21 AZ/EL Rotator Controller

Green Heron RT-21 AZ/EL Rotator Controller

We already have a Green Heron Az/El Rotator controller setup for the Yaesu Rotator system on the 2.0 Antenna Tower and we will be reusing it for the 2.1 station.

GHTracker Running On A Raspberry Pi 3

GHTracker Running On A Raspberry Pi 3

We are also planning to build a second Raspberry Pi Rotator Interface for it.

M2 Antenna Systems PS2MCP8A Polarity Switch

M2 Antenna Systems PS-2MCP8A Polarity Switch

M2 Antenna Systems recently added a new 2M polarity switch, the PS-2MCP8A, designed for use with the 2M antenna in their LEO Pack which we are using in our 2.0 Antenna System. We will be installing this relay as well as a PS-70CM polarity switch relay for the LEO pack’s 70cm antenna as part of the 2.1 Antena System upgrade.

DXEngineering EC-4 Control Box

DXEngineering EC-4 Control Box

We will add another DXEngineering EC-4 BCD Control Console to control the polarity switching relays on the upgraded antennas.

m RM ITALY LA-250V Amplifier

RM ITALY LA-250V Amplifier

The final new component in our 2.0 to 2.1 upgrade is the addition of a 200W RM ITALY LA 250 power amplifier. We have opted for the version of this amplifier with the cooling fans. The unit is very well made and we are anxious to see how it performs on the air.

Some of our readers might be wondering what we are planning to do with all of Portable Satellite Ground Station equipment in the long run? We plan on keeping the 1.0 Portable Station for grid square activations and demonstrations. Its simple, battery-powered approach and small antenna make it ideal for this sort of work.

The upgraded 2.0 Portable Station with its enhanced polarity switching will become our transportable station for License Class and Field Day use. It will be converted at the end of 2018 to use our Icom IC-9100 Transceiver that is currently part of the 3.0 station.

We plan to use the Portable 3.0 Station through the year (2018) to support the planned ARISS contact, Field Day, and some demonstrations at local Ham Fests and schools. Once these are complete, we plan to permanently install it here at our QTH and it will become our main satellite ground station at our home QTH.

You can view all of the articles about our Portable Satellite Stations via the links below.

We will begin construction of the 2.1 upgraded station once a few remaining components arrive here. We plan to share some more about the construction and initial testing of our 2.1 Portable Station here.

Fred, AB1OC

A Portable Satellite Station Part 6 – 3.0 Station Initial Contacts

Tech Class First 3.0 Portable Station Test

Tech Class First 3.0 Portable Station Test

With the construction of our Portable Satellite Station 3.0 complete, we’ve been looking forward to an opportunity to test the new setup. We chose the Nashua Area Radio Society’s recent Technician License Class as a good time to both test the new stations and to acquaint our Tech Class grads with one of the many things that they can do with their new licenses – amateur satellite operations.

Tech Class 3.0 Portable Satellite Antenna Test

Tech Class 3.0 Portable Satellite Antenna Test

The first transport of the new 3.0 station antenna system turned out to be simple. The booms and counterweights of the new antenna system are easily separated via the removal of a few bolts located at the cross-boom. This allowed the antennas feed-points, rotator loops and polarity switching connections to be removed and transported as complete assemblies. The separation of the longer-boom antennas into two sections also made transporting the antennas easier and made the antenna elements less prone to bending in transport. Setup and cabling of the new 3.0 antenna system as the class site was quick and simple.

The opportunities to make contacts during our Tech Class were limited but the new system performed well with one exception. We saw a higher than expected SWR readings on the 70cm yagi during transmit. We immediately suspected problems with one of the N connectors that were installed during the construction of the new system (component testing during assembly showed the SWR readings on the 70cm side of the system to be in spec.).

Portable Satellite Station 3.0 Antenna System

Portable Satellite Station 3.0 Antenna System

After the class, we set up the 3.0 system again at our QTH. Transport and re-assembly of the new system are somewhat easier and faster than our 2.0 portable station antenna setup is.

Satellite Antenna System 3.0 Connections

Satellite Antenna System 3.0 Connections

The 3.0 antenna system uses a similar connector bulkhead approach that we used previously. The rotator controls are handled via a single, 8-conductor cable and we have a new connection for the polarity switching controls on the 3.0 system yagis.

Rotator Loop Coax Retention System

Rotator Loop Coax Retention System

We have had some problems with the connections between the preamplifiers mounted at the antennas and the rotator loops which connect the antennas to them. This problem caused several failures in the associated N-connectors on the 2.0 portable antenna system so we fabricated a simple arrangement to prevent the rotation of the antennas from turning the coax inside the N-connectors and causing these failures.

70cm Yagi SWR in the Satellite Sub-Band

70cm Antenna and Feedline SWR in the Satellite Sub-Band

Some isolation tests were performed on each cabling element of the 70cm side of the 3.0 antenna system and this resulted in the location of an improperly installed N-connector. The faulty connector was easily replaced and this corrected the SWR readings on the 70cm side of the antenna system. The image above shows the SWR readings for the 70cm antenna after the faulty connector was replaced. We checked the SWR performance with the 70cm yagi set for both Left-Hand and Right-Hand Circular Polarization and we saw good results in both configurations.

2m Yagi SWR in the Satellite Sub-Band

2m Antenna and Feedline SWR in the Satellite Sub-Band

We also re-checked the SWR performance of the 2m side of the antenna system with the 2m yagi in both polarity settings and it looked good as well.

Portable Satellite Antenna 3.0 Az-El Rotator

Portable Satellite Antenna 3.0 Az-El Rotator

The 3.0 antenna system uses an Alfa-Spid rotator. The Alfa-Spid can handle the additional weight of the larger yagis and has a more precise pointing ability (1° accuracy) which is helpful given the tighter patterns of the larger, 3.0 yagis.

70cm Yagi Switchable Polarity Feedpoint

70cm Yagi Switchable Polarity Feedpoint

The new yagis in the 3.0 antenna system have feed point arrangements which allow the polarity of the yagis to be switched between Left-Hand Circular Polarity (LHCP) and Right-Hand Circular Polarity (RHCP). These antennas used a relay arrangement at the feed-points that flip the polarity of one plane of the yagis by 180° which in turn changes the polarity of the antennas between LHCP and RHCP.

Portable Satellite Station 3.0 Radio and Controls

Portable Satellite Station 3.0 Radio and Controls

With the SWR problem corrected, we set up the 3.0 station radio and controls. The 3.0 station adds our homebuilt PTT Router and the control box from DXengineering which controls polarity switching. Also, the Green Heron rotator control box has been configured to control the new Alfa-Spid rotator.

POrtable Satellite Station 3.0 Computer Control via MacDoppler

Portable Satellite Station 3.0 Computer Control via MacDoppler

We are continuing to use the excellent MacDoppler software to control the 3.0 station. MacDoppler provides tracking controls for the antennas and doppler correction for the Icom-9100 transceivers uplink and downlink VFOs.

Satellite 3.0 Station Control Details

Satellite 3.0 Station Control Details

The image above shows a closer view of the 3.0 station controls. The box in the middle-left with four LEDs and the knob is used to select one of four polarity configurations for the 2m and 70cm yagis – RHCP/RHCP, LHCP/RHCP, RHCP/LHCP, or LHCP/LHCP. Just to the right in the middle stack is our homebrewed PTT Router which expands and improves the PTT sequencing performance of the station.

So how does the new 3.0 station perform? The new antennas have a tighter pattern requiring careful pointing calibration of the rotators during setup. This is easy to do with the Alfa-Spid rotator. The new antennas have noticeable more gain as compared to the LEO pack used on the 2.0 station. We are also surprised to see how much difference the polarity switching capability makes in certain situations – sometimes as much as two S units (12 dB) in certain situations. The combination of the new antennas and selection of the best polarity combination allows solid operation on many satellites passes with as little as 2 watts of uplink power. We have made a little over 50 QSOs on the new 3.0 station so far and it works great! For more information on the Portable 3.0 Station as well as the 2.0 and 1.0 stations that we’ve built – see the links below:

Fred, AB1OC

 

PTT Router for Satellite Station 3.0

ARR Satellite Preamp

Advanced Receiver Research Remote Preamp

Our Satellite Station 2.0 antenna system uses a pair of Advanced Receiver Research Remote preamplifiers at the antennas to boost weak signals. These preamps have RF sensing and switching to protect them during transit. While this system works well; we are always concerned about the impact of the RF power affecting the long-term reliability of these devices and the associated radio equipment.

M2 Antenna Systems S3 Sequencers

M2 Antenna Systems S3 Sequencers

Our Satellite Station 2.0 uses a pair of M2 Antenna Systems S3 Sequencers to control the preamps remotely. For U/V and V/U mode satellites, it’s a simple matter to turn off the uplink band preamp to protect it against RF during transmit. The problem with this approach comes when working satellites and the International Space Station in simplex (single band) modes. In these situations, we need a solution which keys the sequencers externally so that the sequencers can properly control the changeover of the preamps from receive to transmit mode before keying our radio (an Icom IC-9100). We also wanted a solution which could also allow the radio initiate the keying of the sequencers for CW break-in keying and digital modes.

PTT Router

PTT Router

Our solution was to design and build a simple Push-To-Talk (PTT) router. This device allows an external source such as a footswitch or a trigger switch to initiate the keying. The design also includes indicators which confirm that the keying sequence has completed.

PTT Router Schematic Diagram

PTT Router Schematic Diagram

Our first step was to create a simple design which allowed for either an external switch or the radio to initiate keying. The PTT source switch (S1) selects the keying source and uses the Hsend  (2m key) and Vsend (70cm/1.2 GH key) lines on the Icom IC-9100 accessory jack as either the means to key the radio or the means to detect that the radio has initiated a transmit keying sequence. A second switch (S2) selects which VFO is keyed when the keying source switch (S1) is in External mode. Finally,  indicators for power and keying complete were added.

Rear Panel Connectors

Rear Panel Connectors

A small enclosure was used to house the switches, indicators, and the connections to the rest of our Satellite Station. The image above shows the rear-panel connections to external PTT sources, the S3 Sequencers, the IC-9100 Radio, and a 12 Vdc station power source.

PTT Router Internal View

PTT Router Internal View

A pair of terminal strips were mounted inside the enclosure to make connecting all of the components easier. The wiring is pretty dense around the front and rear panels so connections were insulated with heat shrink tubing. A small PCB could easily be created to make replicating the prototype easier should we decide to build more copies of the design.

Satellite Station 3.0 Controls

Satellite Station 3.0 Controls

Our new PTT router was easy to integrate into our Satellite Station 3.0 setup. Integration required some custom cables to be made to connect our PTT router to the sequencers and to the accessory jack of the radio. With the integration completed, we are now able to properly sequence the control of the preamps and the radio in all modes of operation. Here are some more articles which include more about our portable satellite stations –

Fred (AB1OC)

ISS Crew Contact

We have been working with Hudson Memorial School to help them secure and prepare for an ISS Crew Contact. We are hoping to support their ISS Crew Contact using an upgraded version of our Portable Satellite Ground Station. A school in Raleigh, North Carolina had their ISS Crew Contact today and I decided to record the downlink from the ISS to test our backup Portable 2.0 ISS/Satellite Ground Station.

The video above is a capture of the school’s contact. It was very easy to receive the ISS downlink on our portable backup ground station. I heard the downlink a few seconds before the ISS came up on the horizon and the audio was solid for the duration of the contact. We can only hear the astronaut’s side of the contact as we cannot receive the school’s uplink from Raleigh, NC. The ISS pass began here in New Hampshire part way through the school’s session so we did not hear the first few questions.

Update on Portable ISS/Sat Station 3.0

Portable ISS/Sat Station 3.0 Antenna System

Portable ISS/Sat Station 3.0 Antenna System

Work on our upgraded primary Portable 3.0 Station which includes a larger antenna system using switchable circular polarity is progressing well. The portable tower, upgraded rotator system, and the new, larger 2m and 70cm circularly polarized antennas are complete.  We are just waiting for a few additional components to arrive here and the upgraded portable ground station should be ready for its first test at our Technician License Class later this month.

More on Today’s ISS Crew Contact

You can see a live stream of the ISS Contact from the school above. There is a great deal of planning which goes into an ISS Crew Contact such as this. We are working closely with Hudson Memorial School on their project and their school is also beginning a High-Altitude Balloon Project with us in a few weeks.

The ISS Crew Contact today was exciting to listen too and we are looking forward to being able to share this experience with Hudson Memorial School in the near future.

Fred, AB1OC

An 80m Broadband Matching System

Our Tower with 75m Loop

Our Tower with 75m Loop

We installed a 75m loop for SSB operation on our tower when we built it. The loop is full size and is diamond shaped so that our lower SteppIR DB36 yagi can rotate inside of it. The loop is fed at the bottom corner about 20 ft up from the ground. It works great for SSB operation on 75m but we have often wished we could use it across the entire 80m band. This goal led to a project to create a matching system for the antenna. The idea was to use a set of loading coils in series at the feed point create a good match in all segments of the 80m band.

EZ-NEC Model for 75m Loop

EZ-NEC Model for 75m Loop

The first step in the design of our 80m matching system was to build a model of our current loop using EZ-NEC. The model was then used to determine the correct values of a set of series loading inductors to match different segments of the 80m band.

Matching System Design Analysis

Matching System Design Analysis

We also considered how likely different segments of the 80m band were to be used by profiling historical spotting data from DXSummit. All of this analysis led to the creation of a final design which is captured in the spreadsheet shown above. The final design requires our current 75m loop to be shortened a bit to work well at the very top of the 80m band.

Modeled Loading Coil Inductance Values

Modeled Loading Coil Inductance Values

A set of 5 different inductor pairs can be used in series with the loop’s feed point to create a good match across the entire 80m band. The modeled values for the series matching inductors is shown above.

Matching System Modeled SWR

Matching System Modeled SWR

Our microHAM control system can easily implement the switching of the various inductance values based upon the frequency that a radio using the antenna is tuned to. Result modeled SWR for the final 80m loop and match combination is shown above. The design should achieve an SWR < 1.5:1 across the entire 80m band except for the very top where the SWR remains < 2:1. Also, the design optimizes the system’s SWR in the important CW DX, SSB DX, and Digital windows on the 80m band.

Layout of Components in Enclosure

Layout of Components in Enclosure

With the design completed, we choose an enclosure and all of the components. Here are the details of what we used:

The first step in the construction was to layout all of the components in the enclosure. Attention was paid to keeping the two series inductors at right angles to avoid coupling and to keep RF connections as short as possible. The relays were arranged to keep the leads connecting to the coils of roughly equal length. Finally, the control circuitry was kept as far removed from the RF leads as possible.

Enclosure Mounting Ears and Clamps

Enclosure Mounting Ears and Clamps

The matching system attaches to a tower leg via saddle clamps. We fabricated a set of mounting ears and spacer blocks to position the enclosure far enough away from the tower so that the antenna connections do not interact with the tower.

80m Matching System Construction

80m Matching System Construction

A summary of the completed matching system construction is shown above.The design uses a set of four double-pole double-throw relays to switch in different coil taps which selects the loading inductance provided by the matching system.

We did a set of calculations and found that our relays would be subjected to a worst case peak-peak voltage of about 2.1 KVp-p at the coil tap points.

The relays are arranged such that two sets of contacts have to be traversed to select any given coil tap. The relays we are using have a third pole which we are not using. We disassembled each relay and removed the internal contact wiring for the center pole which improves both the coil to contact voltage rating and the isolation values of the relays.

These steps combine to improve the voltage rating of the system. This is an important design element given that the match will operate at legal limit power.

Completed RF Deck

Completed RF Deck

The completed RF deck and control circuitry is shown above. The enclosure we choose came with a removable plastic plate that made mounting and wiring all of the components simple.

Loading Coil Mounting and Taps

Loading Coil Mounting and Taps

The loading inductors are mounted using nylon hardware with the ends connected to the two antenna terminals on the sides of the enclosure. The coils use movable tap clips to allow us to fine-tune the match once the system is installed with the antenna on our tower. The initial clip locations are set to create the inductance values modeled during the design phase.

Relay Control Circuit Connections

Relay Control Circuit Connections

The relay control leads use twisted pair wiring to minimize RF pickup. The control leads are routed away from the RF connections to minimize potential RF coupling.

Relay Control Circuit Details

Relay Control Circuit Details

The control circuits for each relay use a combination of a Diode, a Varistor (MOV) and a filter capacitor in parallel to avoid relay coil switching interference and to suppress control line noise.

1.5 to 1 Matching Balun

1.5 to 1 Matching Balun

The matching system is designed to operate at 75-ohms which is pretty close to the resonant impedance of our 75m loop. The current antenna uses a 1.5:1 Balun to match the loop to our 50-ohm coax feedline. We disassembled an identical matching balun (actually a 75-ohm balun plus a 1.5:1 unun) and used it without its enclosure to create a final 50-ohm match.

MicroHAM Setup to Control 80m Matching System

MicroHAM Setup to Control 80m Matching System

The final step in the construction of our matching system was to program our microHAM antenna switching system to properly configure the relays in our matching system. This was quite simple to do using microHAM’s frequency dependent antenna control capabilities. The microHAM system automatically operates the appropriate relays to create the best possible match as the radio which is using the matching system is tuned across the 80m band.

Unfortunately, we are in the middle of winter here in New England so I will have to wait for warmer weather to install our new matching system on the tower and make the final adjustments. I am planning another article here when the final integration steps are done to cover the performance of the completed project.

Fred, AB1OC

Receiving SSTV From The ISS

Portable Satellite Station Additions - Digital and Packet

Portable Satellite Station With Additions For Digital and Packet

We’ve recently upgraded our Portable Satellite Station 2.0 to add digital and packet capabilities. The upgrade was pretty simple – we added a SignaLink USB Soundcard and a Windows Laptop PC. Most of the software for packet and digital Amateur Radio communications is written for the Windows OS so using a separate laptop running Windows 10 was the simplest way to go. Another benefit of the second laptop was added screen space to use when doing packet communications via satellites and the International Space Station (ISS).

SSTV Image From The ISS

SSTV Image From The ISS

We recently learned that the ISS was going to be again transmitting SSTV images worldwide. This provided a perfect opportunity to work with the digital additions in our satellite setup. We downloaded and installed MMSSTV on our Windows laptop and set the audio levels on the Windows PC and our SignaLink Sound card to properly receive SSTV signals. The MMSSTV application can decode several different SSTV formats including the PD120 format used by the ISS. The ISS transmits SSTV on a 2m FM voice channel. We configured MacDoppler to track the ISS and perform doppler correction on the 2m ISS 2m downlink and began to listen.

The video above was made during the reception of an SSTV image from the ISS during a pass over the United States. The video gives a good idea of what its like to receive SSTV from the space station.

Another SSTV Image From The ISS

Another SSTV Image From The ISS

We were able to receive several different images from the ISS during the period that it was transmitting SSTV worldwide.

A Third SSTV Image From The ISS

A Third SSTV Image From The ISS

It was pretty easy to capture the SSTV transmissions from the ISS with our Portable Satellite Station 2.0 setup. The signals were strong and I would imagine that the SSTV transmission could have also been received with a simple portable satellite setup with a hand-held yagi antenna.

We hope that the ISS will send SSTV images again in the near future. It was fun receiving them.

Fred, AB1OC

A Winter’s Fox Hunt

Tracking a Fox During a Fox Hunt

Tracking a Fox During a Fox Hunt

Jamey, KC1ENX let the N1FD foxes loose in Nashua, NH this past weekend to give all of us a chance to track them down. This is not the first time that our foxes have roamed to wilds on New Hampshire. We let them loose during our summer picnic this year. We always have fun and improve our radio direction finding skills while doing a Fox Hunt!

Fox News Alert!

Fox News Alert!

We woke this past Saturday to a Fox News Alert! Fox News contributor Jamey, KC1ENX reported –

“Two foxes have been spotted in the Nashua area! It has been reported that N1FD-fox1 was heard on Route 3 this morning on 146.565. It has also been reported that N1FD-fox2 could be heard from close to N1FD-fox2’s location on a frequency of 146.535.”

Hunting the Large Fox

I went down to our shack and turned on the 2m rig. Sure enough, there was the howl of the large fox (audio recording above) so I gathered my HT and Elk Yagi antenna and set off to track down the Wiley critters. I stopped just beyond my house near Rt. 122 in Hollis, NH to get an initial fix. Sure enough, I heard the large critter’s bark coming from the general direction of Nashua. A couple of fixes along Rt. 3 indicated that the fox was in a den in Mine Falls Park so I drove there and parked. By this time, the fox was clearly audible on the mobile rig in my truck. I switched my HT to the big fox’s third harmonic frequency and headed for a high spot on a bridge in the center of the park. Sure enough, there the Wiley critter was – just ahead on the trail.

The Large Fox in its Lair

The Large Fox in its Lair

I got very close to the large fox when I encountered Bob, W1FDR who had a very effective close in system which used an HT and a dish. Bob said:

“Lets team up and we’ll track the critter down”

So we did team up and it did not take long to find the fox’s hideout. We both signed the fox log and turned our attention to finding the smaller fox.

Hunting the Small Fox

Bob W1FDR by the Small Fox’s Den

Bob W1FDR by the Small Fox’s Den

The small fox was audible from the large fox’s den using my Yagi and HT. We tracked the small fox across the soccer fields at Mine Falls Park and over a small ridge. Once we got close, Bob used his dish system to track down the small fox in its den.

Fox Hunting Equipment

Fox Hunting Equipment

The combination of my Yagi and Bob’s dish system worked very well for hunting the foxes. The Yagi was surprisingly directional at longer range and this made it relatively easy to get close to both foxes. Bob’s dish was great for the final, close-in location of the foxes in their dens.

I had a great time hunting the foxes and I am looking forward to another hunt this coming Saturday after our breakfast get together at Parker’s Maple Barn in Mason, NH. I am looking for some folks to team with again for the hunt this coming Saturday. Talley-ho!

Fred, AB1OC

Propagation Prediction Websites

Is 20 meters open to the location of the latest DXPedition on the bands?   When is 6 meters open for Sporadic E?  Looking for a weak signal 2 meter contact with a specific grid square?  There are websites you can visit that give you a prediction of whether the band you are on is open to a given destination.

HF Propagation

N0NBH Propagation Widget

N0NBH Propagation Widget

The simplest HF propagation prediction is the widget that is seen on many Amateur Radio Websites – QRZ.com, DXSummit.fi, and more.   This gives you a rough idea of what bands are open day and night. Data is based on the Sunspot Number, A and K indices and other indices.  But this doesn’t take into account many factors like your location, the DX location, the characteristics of your station and the DX station.  Just because 15m says Poor doesn’t mean you won’t hear anything on the band.

VOACAP – HF Propagation Prediction

VOACAP Point to Point Prediction

VOACAP Point to Point Prediction

VOACAP, is the Voice of America Coverage Analysis Program, and provides detailed information about the HF propagation.  You can choose transmitter and receiver locations from many cities around the world.  It also provides choices of Antennas, Power, Mode, and more for each end of the contact. You can look at several different views of propagation.  If you spend some time delving into the details of propagation visit this site.

VOACAP Prediction from DXSummit.fi

VOACAP Prediction from DXSummit.fi

For a faster view of whether you will be able to contact a specific DX Station that is currently on the air,  the DXSummit.fi spotting website has incorporated propagation predictions on their website.  If you find a DX station spotted there that you contact, just right click on the DX callsign and select VOACAP from the drop-down.   You just need to choose whether you are a Basic (100 watts and a Wire) or a Super station (Amplifier and Directional Antenna).  You can also look at views of Short Path or Long Path.  It will give you a good view of when you need to be on which band to contact the DX station.

6 Meters – The Magic Band

DXMaps - 6 meter openings

DXMaps – 6 meter openings

The best website that I have found for 6 meters is DXMaps.com .  It provides a map view of the world or you can select a continent. Based on spotting network data, it shows 6 meter contacts and color codes them by Sporadic-E, Multihop ES, Meteor Scatter, etc…  even Aurora.  You can also get a view of 10 meters, 2 meters or 70 cm.  If you sign up for a free account, you can subscribe to real time notifications when there is an opening near you.

2 Meter Propagation

VHF Propagation Map

VHF Propagation Map

Looking for a tropo opening for a weak signal 2 meter contact?   Visit the website http://aprs.mountainlake.k12.mn.us/ to see a VHF Propagation map.  This shows tropo openings as color coded clouds – with brighter colors for the longer openings.    This is based on APRS data.

These are the websites that I like to visit to understand the propagation forecast for the day.  If your favorite site is not on the list, add a comment so that we and the rest of our readers can check it out.