The spectrum scope and waterfall
On radios with a spectrum scope, the console shows it live: a spectrum line on top and a scrolling waterfall below. The scope data comes from the radio itself, so it shows what the radio's own scope shows.
On a Hermes Lite 2 the agent draws the spectrum itself from what the radio sends, from ±2.5 kHz to ±100 kHz. Radios without a scope, and Kenwood, Yaesu and Elecraft radios for now, don't show this panel. The supported radios list says which radios have one.
Reading it
- The spectrum shows signal strength across the span, with stronger signals higher. It's colored by how far a signal stands above the noise: orange at the noise, yellow by about 10 dB over it, blue by 25 dB, and red for the strongest signals, 40 dB and more.
- The waterfall shows the same thing over time, newest at the top. Weak signals are dark blue; stronger ones run through cyan and yellow to red.
- The red line marks the frequency you're tuned to.
- The lighter band around it is the radio's receive filter: what you hear. It follows the filter width as you change it, sits on the sideband you're on in SSB, is centered in CW and AM, and moves with RIT while RIT is on. Its edges carry on down the waterfall. It shows on radios that report their filter width (Icoms and FlexRadios), not in FM. On an Icom the SSB band is drawn about a center near 1.5 kHz, as Icom narrows the filter, and PBT isn't drawn, so it's a close guide rather than an exact trace.
- Faintly across the top of the spectrum are the day's propagation numbers, from NOAA's Space Weather Prediction Center and updated every 15 minutes: SFI, the solar flux (higher opens the upper HF bands); SSN, yesterday's sunspot number; A and K, how disturbed the Earth's magnetic field is (lower is quieter; K of 5 or more is a storm); and the latest X-ray class (M and X flares can black out HF on the daylit side). Your device fetches them itself, so they need its internet connection. Turn them off or on with Solar numbers under Scope on the Controls tab (under Levels in the Phone layout).
- On your station address, DX cluster spots show along the top of the waterfall: each station's call at its frequency, from the last half hour, in the color of the DX cluster panel's badge: red for a new one, orange for a new band, white for the rest. Click a call to tune to it. Turn them off or on with DX spots on the waterfall, next to Solar numbers.
- The band map across the top shows which part of the band you're looking at: CW (blue), Data (purple), FT8 (teal), SSB (green), AM (amber) and FM (pink). It follows the ARRL (US) band plan, simplified; other regions differ in places, so treat it as a guide. The AM windows are marked in amber: 1.880–1.890, 3.870–3.900, 7.280–7.300, 14.280–14.290, 21.400–21.430 and 29.000–29.100 MHz, and 50.400 MHz on 6 m. Narrow segments, such as FT8 or an AM window on a wide span, show their color without a label; hover over one to see its name and frequencies.
- The numbers below it are the frequencies of the left edge, the center and the right edge, in MHz.
- Out of range appears when the radio reports that its scope is out of range.
When the console first connects, or just after the radio is turned on, the panel may say Waiting for spectrum data… for a few seconds.
Tuning from the scope
Tap or click anywhere on the scope or waterfall to tune to that frequency. The console rounds it to the nearest 100 Hz. Then fine-tune with the frequency digits or the tuning strip (see Using the console).
To move a VFO along the band, drag it: press on its marker or anywhere in its shaded filter and slide sideways. The frequency follows in 10 Hz steps as you drag. With the scope in center mode, the scope follows VFO A, so A stays in the middle while the band slides under it.
Click a segment on the band map to jump to it: the radio tunes to the middle of the segment and the span changes to show all of it (on 20m, clicking SSB tunes to 14.250 MHz at ±100 kHz). Clicking an AM window tunes to its middle (3.885 MHz on 80m, say), or to 50.400 MHz on 6 m, in AM, and leaves the span as it is. Clicking FT8 does what the FT8 mode button does: it tunes to the FT8 frequency and sets the radio up for FT8 (see Operating FT8).
A second VFO, for split
To work a DX station that listens on another frequency, add a second VFO with + VFO B, at the bottom left of the waterfall. VFO B appears 10 kHz up the band, drawn as VFO A is: a marker line, with its filter shaded on the scope and its edges carried down the waterfall.
Each VFO has a flag beside its marker, as SmartSDR flags its slices, with the VFO's letter and frequency:
- RX, on A, is where the radio receives. The radio always receives on A.
- TX is lit on the VFO the radio transmits on. Click the TX on B to transmit there (the radio goes into split, and the badge above the frequency reads SPLIT · TX and B's frequency); click the TX on A to transmit on A again.
- The letter that's lit (and its flag's red outline) marks the VFO a click on the scope tunes. Click B, then click a signal to put B on it; click A to tune A again.
The flags face apart, the lower VFO's to the left of its marker and the higher's to the right, and B's drops a row if they'd overlap. Drag either VFO's marker or filter to move it along the band (see Tuning from the scope). When a VFO is off the scope, a tag at that side shows its frequency.
With B added, the radio panel above splits in two halves, VFO A and VFO B, each with its own frequency display, tuning strip and step (see Frequency). The meter sits in the half of the VFO in use: A's, or B's while transmitting in split.
At the bottom left, ⇄ swaps A and B, to listen where you were transmitting, and × VFO B removes B (and turns split off). Each device remembers whether it shows B; it shows on every console while the radio is in split.
For now this is on Icom radios that report their second VFO: the console offers + VFO B only when the radio answers for it. FlexRadio, Kenwood, Yaesu, Elecraft and the Hermes Lite 2 show the SPLIT badge when the radio is in split, but not B yet.
Changing the span
The tools sit at the bottom right of the waterfall. The last pair, − and + either side of the span, change how much of the band it shows, centered on your frequency:
- − widens the span, to see more of the band.
- + narrows it, to see signals close to your frequency in more detail.
The span is shown between the buttons, from ±2.5 kHz up to ±500 kHz. A button grays out at the end of the range.
The span you choose is set on the radio, so it's also what you'll see on the radio's own screen.
Center or fixed
The button beside the span switches the scope between Center and Fixed:
- Center: the scope follows VFO A, which stays in the middle while the band moves under it.
- Fixed: the scope stays put as you tune, and the VFO markers move across it, which suits dragging a VFO around a band. Tuning off the scope (to another band, say) moves it to where you tuned.
On an Icom, Fixed is the radio's own fixed-edge mode, so the scope shows the edges set for that band on the radio, and the span label says Edges. Tapping − or + then switches the radio's scope back to center mode at ±25 kHz. On a FlexRadio, the panadapter stays where it is (SmartSDR's autopan off), and − and + still change its span. The Hermes Lite 2's scope is always centered on its frequency, so it has no Fixed.
Waterfall height
In every layout, drag the small bar under the scope to make the waterfall taller or shorter, or select the bar and use the up and down arrow keys. Double-click it to go back to the layout's own height (in the Panadapter layout, fitting the window). Each layout keeps its own height, and each device remembers it.
Waterfall speed, gain and contrast
These change only how the scope looks on your device, not the radio, and each device remembers its own:
- Speed (Fast, Med or Slow): click to change how fast the waterfall scrolls. Slower speeds keep the strongest signal from the moments in between, so short signals still show.
- Gain (−5 to +5): brightens the waterfall and lifts the spectrum line. Turn it up when a quiet band looks black, down when everything looks yellow.
- Contrast (−5 to +5): spreads the colors apart, so weak signals stand out from the noise. Too much makes the noise speckled.
On a phone they're labeled G and C to fit.
Data use
The scope streams continuously while the console is open, so it adds to the data the console uses. Keep that in mind on a metered cell plan.