JG-BPF2M 3-cell bandpass filter (helical/helix filter) 144MHz
Ideal filter for contest stations bordering LTE, commercial FM, and civil transmitters; also perfect for EME or DX use.
A helical/helix bandpass filter for the 2-meter band (144MHz), entirely designed for the most demanding amateur radio operators but very useful for those who want more from their station.
Applications:
For powers below 200W, it can be connected without the use of coaxial relays.
https://www.hamradioshop.it/8748-thickbox_default/jg-bpf2m-filtro-passa-banda-3-cellehelical-helix-filter-144mhz.jpg1) The filter can be installed between VHF radio -> FILTER -> VHF amplifier -> antenna
2) The filter can be installed between antenna -> FILTER -> VHF radio
3) The filter can be installed between antenna -> FILTER -> transverter -> HF radio
4) The filter can be installed between antenna -> FILTER -> PRE -> radio/transverter
Example:
With a 144 -> HF transverter, it can be installed at the input/output of the transverter (usually 30/60W out) to eliminate any intermodulation products.
Example: I have a transverter with an IF output at 28MHz.
The transverter's LO is 116MHz. At the input of the transverter's front end, we have 116+28 = 144MHz and 116-28 = 88MHz.
Often, preselectors cannot completely eliminate the FM band.
The helical filter is the result of months of study and technical tests to finally offer insertion losses of approximately 0.3dB at 144 MHz.
Description
Area of use:
VHF 144MHz (2 meters) bandpass filter entirely made from solid anticorodal 6060 aluminum alloy.
Allows perfect reception of the 2-meter band from 144 to 146MHz with low insertion loss (typically 0.35dB)
Completely eliminates FM broadcasting from 88 to 108MHz thanks to an attenuation of over 90dB
Perfect for:
- Eliminating intermodulation problems on radio systems operating in the 2-meter band
- EME, TROPO, CONTEST, and SAT stations
- Amateur radio repeaters
- Possibility of tuning the filter also for CIVIL APPLICATIONS from 130 to 170MHz
Uniqueness:
Helices made of 3mm silver-plated copper
Filter machined from solid aluminum using a 3-axis mill
Lightweight and compact for installation anywhere
Connectors:
N female Amphenol®
N female Amphenol®
Materials:
3mm silver-plated copper coils
Anticorodal 6060 aluminum filter
Stainless steel screws
Technical characteristics:
- Filter entirely made from solid aluminum via CNC milling process
- Stainless steel hardware
- Aluminum cover with 24 fixing screws, laser cut to a thickness of 4mm.
- Amphenol N female to N female connectors or, depending on availability, N female to N male.
- Silver-plated copper coils with 3mm diameter.
- Dimensions: 145x77x48mm
- Weight: 1Kg.
- Typical transmission power: 200W.
- Typical return loss: -25dB.
- Reversible filter
- Features a "natural" notch on FM broadcasting ( -100dB @ 98MHz )
- Typical insertion loss: 0.35dB
- Attenuation at 98MHz: 90dB
Graph:
Measurement of scattering parameters (gain and return loss) S11, S21, S12 and S22 performed using a calibrated Rohde&Schwarz mod. ZNL3
