We have decided to discontinue the SteppIR products. We also offer a range of accessories for SteppIR products, see list. If you are interested in multiband antennas with variable length elements, please contact us. We will be happy to advise you about alternative offers, such as Ultrabeam.
Available SteppIR Products
Content of this page
SteppIR manufactures freely tuneable multiband beams with 2, 3 or 4 elements for 40 to 6m or 20 to 6m. With the continous mechanical tuning of the element lengths SteppIR Yagis achieve the performance of comparable monoband beams - but on many bands. The similar contructed λ/4 verticals offer always perfect match as tuned groundplane. The small packing size and the lightweight construction with glassfibre tubes makes these antennas an ideal companion for dx-peditions and fielddays.
The problem with traditional beams
Traditional multiband beams require traps, interlaced elements etc. to work on multiple bands. With these elements such an antenna is usually a compromise in respect to the possible maximum efficiency of an antenna. Monoband beams like the ZX Yagis would be an alternative, but who can put up three or more such beams?
The idea: variable lengths elements
FluidMotion, the manufacturer of SteppIR antennas has solved this problem in an elegant way. SteppIR vary the mechanical length of each element by means of a retractable metal band. This allows the antenna to be adjusted for any frequency (within the range) and work near the perfect optimum.
Contruction of a SteppIR
Each element of a SteppIR antenna consists of lightweight glassfibre tubes, the metallicc band run in these tubes. That means of course that the absolute size of the antennas does not change, the glasfibre tubes are not changed in length. The metallic bands are made of a special Copper Beryllium (CuBe) which withstands millions of movements. The excellent electrical contact is achieved with four self cleaning slider contacts for each element. The metal band itself is perforated, a sprocket wheel spools up the band. The sprocket is driven by a precision stepper motor, allowing for very precise positioning.
Each single element is controlled by a 4 wire cable, i.e. the 4-element SteppIR yagi requires 16 wires. Down in the shack a supplied controller is used to adjust the antenna. For the amateur bands various presets are available for each band. Further a "general" mode allows adjustment of the antenna to any frequency (within the specified range). Antenna setups can be stored for later recall, other functions allow the quick reversal of direction or the bi-directional mode where the gain is evenly distributed in two directions. An optional CAT interface for the controller allows direct control from most amateur rigs: the antenna is continously adjusted when the frequency on the rig is changed.
Optional 30/40m Radiator
This replaces the standard radiator and allows operation down to 40m. Available in two version: one as option when buying a new antenna and one as replacement part for an existing antenna.
Technical data and comparison table
|Dipol||2 Element Yagi||3 Element Yagi||4 Element Yagi||DB-11||DB-18||DB-18E||DB-36||
|Frequency range (continous)||13,8 - 54||13,8 - 54||13,8 - 54||13,8 - 54||13,8 - 54||6,8 - 54||6,8 - 54||6,8 - 54||3,5 - 54||6,8 - 54||3,5 - 54||MHz|
|Max. Wind speed||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||~ 160||km/h|
|Boom diameter||-||4,5||4,5||4,5 & 5,7||4,45||5||5||4,5-6,35||4,5-6,35||13||13||cm|
|Max. Mast diameter||53||53||53||53||53||53||53||53||53||53||53||mm|
|Required Control cable||4||8||12||16||16||16||16||16||24||25||25||Wires|
|Balun incl.||No (optional)||Yes||Yes||Yes||Yes||Yes||Yes||Yes||Yes||Yes||Yes|
|Price||1455.00 €||1999.00 €||2730.00 €||4110.00 €||3899.00 €||4440.00 €||5120.00 €||7270.00 €||8300.00 €||9399.00 €||10425.00 €|
|Order No 6m Option||12100.63||12100.64||12100.63||12100.63|
|Price||129.00 €||199.00 €||129.00 €||199.00 €||Euro|
|Order No. incl. 30/40m Dipole||12105.2||12105.3||12105.4|
|Price||2629.00 €||3360.00 €||4740.00 €||Euro|
1 According to the manufacturer operation on 30m may require a tuner.
SteppIR Gain and F/B Ratio with Beams (PDF, English, 210KB)
SteppIR Yagi instructions (PDF, English, 2MB)
SteppIR 4-Element Beam Spec Sheet(PDF, Englich, 600KB)
SteppIR 4-Element Installation Instructions (PDF, English, 2MB)
SteppIR 4-Element Operators Guide (PDF, English, 520KB)
SteppIR Serial Interface Guide (PDF, English, 50KB)
SteppIR Trouble shooting Guide for Yagis (PDF, Englisch, 112KB)
SteppIR Trouble shooting Guide for Verticals (PDF, Englisch, 86KB)
SteppIR Dipoles and Yagis
The SteppIR Dipole and Yagis are available in five different versions, from one to 4 elements, covering different ranges. Each element is variable in length by using a motor driven metal band (Copper Beryllium). The metal band is protected by a glasfibre tube, the length of this tube does not change of course.
Like with all SteppIR antennas the glassfibre tubes have to assembled and isolated at first set up. This makes the SteppIR antennas very compact, that nice for shipment cost and expeditions.
Variable element length, but fixed element distance?
One of the most frequently asked questions is "Shouldn't the distance of the elements also change when changing element lengths?". To answer this question it is important to understand that Yagis can be designed to maximise different values. That can be max. gain, best Front/Back ratio, good bandwidth etc. But - these goals cannot be achieved all at once with the same design. Either you optimize a yagi for best gain, useful bandwidth and not so good F/B ratio. Or excellent F/B ratio at narrow bandwidth and mediocre gain etc. etc.
With a 3-element beam the optimum gain would be reached at a boom length of 0.4 λ. The best F/B ratio is achieved with a boom length of approx. 0.25 λ, but only at limited bandwidth. This results in 0.3 λ as a good compromise, with this it can be shown that a variable element length results in much greater effect than variable distance. Bandwidth is of no importance with a SteppIR antenna because the antenna can be adjusted to any operating frequency (within specified range). So a narrow bandwidth design can be selected which results in the best compromise solution at a given element distance. That is much more than what you can expect from a traditional monobander.
Gain and Front/Back ratio
- G: Gain [dBi]
- FBR: Front/Back Ratio [dB]
|Dipol||2 Elem. Yagi||3 Elem. Yagi||4 Elem. Yagi||4 Elem. Yagi MonstIR||DB-11||DB-18||DB-18E||DB-36||DB-42|
- Gain in dBi (Free space)
- F/B ration in dB. The manufacturer denotes this value as "Front/Rear" and refers to the max. achieveable bakwards attennuation, whose maximum is not necessarily in the -180° direction.
SteppIR Dream Beam DB-11
The DB-11 is the smallest beam of SteppIR Yagi antenna which uses the loop technology. This allows the full performance can be achieved despite a 40% smaller area.
The DB-11 has an integrated coaxial switch that selects which is the radiator of the 3 elements in order to ensure the same performance in both directions. The control of the switch is integrated into the control unit SDA 100. The DB-11 is the only 6m antenna without optional element, because the distance of the 3 elements to each other is ideal for operating in this band.
With two active elements on 20m and 3 semi-active elements on 20m, the average gain is 7 dB and the front / back ratio 20 dB per band.
|12113||SteppIR DB-11||3899.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|Info freight charges|
SteppIR Dream Beam DB-18, DB-18E
The DB-18 beams by SteppIR extend the well known antenna principle with variable length elements. With the previously existing SteppIR Beams the 30/40m element was the only element for these bands, resulting in no gain compared to a dipole. The Dream Beam uses 2 (DB-18) or 3 (DB-18E) such folded elements to achieve a gain and good front/back ratio also on 30 and 40m.
Both antennas, the DB-18 and the DB-18E, offer an automatic selection of the driven element, depending on frequency and 180° reversal. This is because shortened elements don't work well as directors, so the radiator is switched from the center element to one of the outer elements. The other two elements act as refelectors in this case.
The switching of the feedline is done with a solid 5KW, 3 port antenna switch. The switch and the required cables to each element are included in the shipment. The selection is done automatically by the new SDA-100 controller, which is included with these antennas. Both Dream Beam antennas require a control cable with 16 wires (3x4 for elements, 1x4 for switch).
|12115||SteppIR DB-18||4440.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12115.E||SteppIR DB-18E||5120.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|Info freight charges|
SteppIR Dream Beam DB-36, DB-42
In the series of large antennas by SteppIR we offer two new models. The DB-36 has the dimensions of a conventional multi-bandyagi and is still always a mono-band beam. In addition to those already contained bands from 6m to 40m, this antenna can be increased with a 80m option.
SteppIR DB-42 (MonstIR PRO)
The world's largest Yagi antenna with a dynamic system. The DB42 has 5 elements on 20m-6m and 3 elements on 40/30. For those who aspire to the top of performance, the DB42 provides a frequency range from 80m to 6m (80m dipole with optional kit). The 6m option adds 3 passive elements without increasing the surface wind. Thus, the DB42 on 6m total of 8 elements with a gain of 14.0 dBi and 25 dB front / back ratio.
|12116||SteppIR DB-36||7270.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12116.80||SteppIR DB-36 with 80m||8300.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12117||SteppIR DB-42||9399.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12117.80||SteppIR DB-42 with 80m||10425.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|Info freight charges|
SteppIR vertical antennas
Besides the SteppIR Yagis two vertical are available which work with the same elegant principle. In a vertically mounted glassfibre tube a metal band made of CuBe is extended or retracted. The band is wound with a stepper motor, changing the electrical length of the antenna, without lossy traps, loading coils etc.
This type of antenna of course requires a good radial network (not included). The radial network strongly affects the performance and critical values like radiation angle of the antenna. And especially vertical antennas are known for the low take-off angle, good for DX.
Radials networks can be designed either as elevated radials or ground radials. Elevated radials require tunes lengths at λ/4, at least two per band. Ground radials can be of any lengths, but at least λ/10 in length, the more the better. The operators manual of the SteppIR verticals gives many more useful hints for constructing a good radial network.
Two verticals are available: the SmallIR covers 20 to 6m, the BigIR covers 6m to 40m (with option up to 80m). Technical data see table below. Included with the vertical SteppIR antennas is the SDA-100 controller.
|SmallIR Mk3 Vertical||BigIR Mk4 Vertical|
|Frequency range (continous)||13,8 - 54||6,9 - 54||MHz|
|Max. Wind speed||~ 160||~ 130||km/h|
|Required control cable||4||
8 with 80m coil
80m extension coil for BigIR Antenna
Extension coil for BigIR vertical antenna, enables operation also on the 80m band. Max power load 500 W (1600 W with new BigIR Mk3). Requires 4 additional wires in the control cable.
SteppIR 80m Option for Vertical BigIR Mk4 (Manufacturer part nº. 06021), instead of 556 € now only 389 €. You save 167,00 €! Only while stock lasts.
|12120.V20||SmallIR Mk3 Vertical 20-6m||1299.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12120.V40||BigIR Mk4 Vertical 40-6m||1549.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12120.V80||BigIR Mk4 Extension only||389.00 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|Info freight charges|
SteppIR BigIR Instruction Manual (PDF, English, 1.6MB)
SteppIR Radial Systems for vertical Antennas (PDF, English, 162KB)
SDA-100: Controller for all SteppIR Antennas
The SDA-100 offers an improved lightning protection on the driver circuits, compared to the standard controller. The driver chips are now socketed for easier replacement.
Additionally we offer (optionally) the 'advanced lightning protection' (ALP), with add more protection against lightnings and static discharge.
The CAT control (requires CAT option) can be switched on and off with a button. A blinking LED shows if the antenna is currently tuning or not.
- Additional button to retract the elements
- Button with LED to show the current direction (normal or 180°)
- Firmware updates of the SDA-100 are possible over an USB interface; the firmware is available on the SteppIr website
- Improved and faster manual frequency control
- Two lines, backlit LC display
Tuning Relay for SDA-100
Prevents the keying of a power amplifier while the antenna is tuning, avoiding damages to the antenna.
|12150||SDA-100 without ALP||666.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12150.ALP||SDA-100 with ALP Note: The ALP option can not be retro-fitted.||1029.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12150.CAT||CAT Option for SDA-100||148.00 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|Info freight charges|
CAT Interface Option
An option for the controller is a serial CAT interface. With this option the controller can be connected to most radios, the antenna adjustment is following the tuning of the radio. SteppIR does offer suitable cables for most radios. The simultaneous use of the CAT interface for the antenna controller and a logging program requires a "Y" connector (order no. 12146).
- Cable 12145.I for all Icom rigs with CI-V interface
- Cable 12145.FT897 for K2, Yaesu FT-920, FT-897, FT-897D (requires CT-62)
- Cable 40060.FF serial Cable f/f, for Kenwood TS570, TS870 (requires Kenwood Adapter), TS2000
- Cable 40060.MF for Yaesu FT-857 (requires CT-62), FT-897 (requires CT-62)
- Cable 40060.FF for Yaesu FT-920
- Cable 40060.MF for Yaesu FT-990 (requires ROM Vers -04 or newer, requires ser. interface)
- Cable 40060.MF for Yaesu FT-1000D (requires FIF-232)
- Cable 40060.MF for Elecraft K2 (requires K2 Serial Kit)
|12142||CAT interface for standard controller||143.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|12150.CAT||CAT interface for SDA-100 controller||148.00 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|12145.I||Cable SteppIR - Icom||34.50 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|12145.FT897||Cable SteppIR - Yaesu FT-897, FT-920, K2||34.50 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|MK-ILINK-STE||Cable SteppIR - microHAM MK-2||38.50 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|40060.FF||Serial data cable 9pin female/female, 1.8m (suitable rigs see list)||4.00 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|40060.MF||Serial data cable 9pin male/female, 3m (suitable rigs see list)||3.60 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|12146||"Y" adaptor||63.20 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|Info freight charges|
Replaces the supplied terminal strip which is used to connect the wires from the stepper motors to the control wires. Now solderless, very comfortable connection of the single wires from the motor units with plugable strips. An additional D-Sub socket allows easy testing. Waterproof box which is mounted directly to the mast clamp.
|12148||Connector Box SteppIR||255.00 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|Info freight charges|
D-Sub 25 Adaptor
Adaptor for control cables to 25pin D-Sub connector. Very practical device for OMs who don't want to solder, or for people who need to change the cable often for experimentation. For each pin of the D-Sub 25-pin connector there is a screw terminal on the rear of the adaptor. Requires only a simple screwdriver.
|12149||D-Sub-25 Screw Terminal Adaptor SteppIR||38.50 €||Unfortunately this product is not available anymore. Sorry. ⓘ|
|Info freight charges|
33V Power supply
Replaces the supplied 24V power supply, recommended for cable lengths over 60m.
|12143||33V Power supply SteppIR||110.00 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|Info freight charges|
Control cables for SteppIr antennas
Each element of a SteppIr antenna requires four control wires. We offer cables with 6 wires with 0.14mm² or 12 wires with 0.34mm² cross section. This is sufficient for cable lengths up to 20m. For larger distances the manufacturer suggests to use larger diameter wires or use of a voltage booster (optional 33V power supply).
Unfortunately we don't carry 8 wire control cables for this purpose (the 8 wire rotor control cable is too large). Best is to use our 12-wire cable and use only 8 of those wires. Control cables are here.
|40012.6||6-wire 0,14mm² per Meter||1.25 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|40012.12||12-wire 0,34mm² per Meter||1.90 €||Add to shopping cart||In stock, shipped in 4 to 5 days. ⓘ|
|Info freight charges|
Due to the new working principle of the SteppIR antennas it can happen that something is misunderstood or incorrectly asembled. For cases where the antenna is not working as expected, SteppIR offers this document (PDF, english, 120KB) which helps you locating the trouble. ALthough this document was written with 3-ele and 4-ele Yagis in mind it is helpful for any model of SteppIR antennas.
FAQ and more information for SteppIR antennas
2: How does the control box for a MonstIR Yagi (40-6m) look like?
3: When adding the announced 30/40m element to an existing SteppIR Yagi, what is changed at the control box?
4: How does the windload and weight change when adding the announced 30/40m element to an existing antenna?
5: How are the new bands (30, 40m) operated when adding the announced 30/40m elemnt to an existing SteppIR antenna?
6: How does the announced 30/40m element look like? Pictures?
8: What are the longterm experiences with SteppIR Yagis? Especially under severe weather?
9: Other users of SteppIR antennas report a slight "rustling" noise, comning from the elements. Any remedy for that?
10: What is the sag of the elements of a standard (20-6m) SteppIR Yagi? And with the MonstIR (40-6m) Yagi?
11: Is it possible to install the announced 30/40m dipole element to any other beam (non SteppIR)?
12: When will the annoucned 30/40m element be available?
F1: When adding the 6m element to a 3-ele (4-ele) SteppIR, what will change in the software?
A1: The 6m option is enabled in the setup menu. SOme controllers might require a software upgrade.
F2: How does the control box for a MonstIR Yagi (40-6m) look like?
A2: Same as for the other antennas. The 30 and 40m band are access via the menu.
F3: When adding the announced 30/40m element to an existing SteppIR Yagi, what is changed at the control box?
A3: A new chip with a new firmware has to be changed in the control box.
F4: How does the windload and weight change when adding the announced 30/40m element to an existing antenna?
A4: The windload increases by 0,2m² (2 ft²), the weight increases by approx .4kg.
F5: How are the new bands (30, 40m) operated when adding the announced 30/40m elemnt to an existing SteppIR antenna?
A5: Together with the new firmware chip (see Q3) a decal is supplied for the control box.
F6: How does the announced 30/40m element look like? Pictures?
F8: What are the longterm experiences with SteppIR Yagis? Especially under severe weather?
A8: SteppIR antennas are in use since about six years (as of summer 2006). In the beginning there were slight problems with the insulation of the glass fibre tubes, but that has been solved.
SteppIR antennas are in use worldwide by radio amateurs and commercial services, also under severe conditions. Just chek the pictures... (click for a larger view).
F9: Other users of SteppIR antennas report a slight "rustling" noise, comning from the elements. Any remedy for that?
A9: The noise is known, it is caused by wind moving the elements slightly. Unfortunately there is no remedy for that, the radiating copper band has to run freely in the glassfibre tubes. The best suggestion is to fully retract the elements when the antenna is not in use.
F10: What is the sag of the elements of a standard (20-6m) SteppIR Yagi? And with the MonstIR (40-6m) Yagi?
A10: The elements of a standard SteppIR yagi (20-6m) have a sag of up to 8" (20cm), the elements of a MonstIR (40-6m) yagi up to 20" (50cm).
F11: Is it possible to install the announced 30/40m dipole element to any other beam (non SteppIR)?
A11: No, the manufacturer strongly discourages this for a whole plethora of reasons. It is not known if any ever tried or succeeded doing so. SteppIR and WiMo do not support installations like that.