Archive for the ‘Antennae’ Category.

Quick and dirty 868MHz antenna in 5 minutes

This is simple antenna for 868MHz built in 5…10 minutes. Take about 10cm of RG214, a plate of PCB with the copper at one (or both) sides. Remove the coax shield and inner dielectric on one side in length of about 85mm. You will cut this to proper length during SWR measurements.

Simple antenna made with piece of coax and piece of old PCB.

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Collinear antenna for 868MHz Lorawan Gateway

This is description of coaxial collinear antenna for 868MHz applications. I designed this for Lorawan gateway.

Antenna tested with lorawan gateway

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6×1 antenna switch

This is complete project for 1×6 antenna switch. It was bult in more than 50 pieces around the world and performs really good. Even big guns use it for their systems. The project was designed with help from other OMs (S55O, S59MA, S50LD, S51CT, S51ZJ, SM2WMV/SJ2W and others).

6×1 antenna switch

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Cheap sh*t magnetic pickup

Do you ever wondered how much magnetic field garbage is around you? This is cheap and easy build to measure magnetic noise or to compare which switching supply is more sh*tty.

Near field probes are nothing new. It’s easy to find one via web search. Here is one good reference for H and E field probes which I found via google image search:

EMC near field probes for H and E field

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3D printed Loop antenna

Branko, one of the famous experts for old(ish) radio devices designed magnetic loop antenna, which can be 3D printed. Here are complete instructions in german language:

Germany-Flag-iconLoop Antenne aus dem 3D-Drucker

Slovenia-icon Slovenski opis (in Slovenian language)

Alluminium vertical for 40m

I bought 6 alluminium tubes, 2m long, diameter from 45 down to 20mm for 40m quarter wave vertical antenna. This 10m simple construction collapses to 2m pack with nly 45mm diameter. The base is made from PVC plastic isolator, which is fixed to alluminium plate with 4 M6 screws and additional nut, placed inside the plastic hole, which is normally used to fix the steerer tube on the bicycle.

Photos are worth more than 1000 words…



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4 element Yagi for 6m, part II

This is part II for 4 element 6m yagi. Part I is about metal parts. Here is some brief description about electrical connection and preliminary test.

4. Antenna feed

To finish the antenna few parts must be 3D printed (or produced with other materials, like plastic pipes). Holder for air coil consists of three parts: coil holder, coil support and connector holder.

Coil holder is simple cylinder (pdf drawing: chokeholder), which is long enough to accommodate 12 turns of RG58 or similar cable:


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4 element Yagi for 6m

6m band is sometimes called “magic band”. It has combined propagation properties of HF and VHF. When conditions are good, very long DXs are possible. Beside the sporadic E occurence some other requirements are essential. One of the most important pieces of equipment is good antenna. There is no shortcut for good performance in small package. Good antenna is big when lambda is long. For 6 meters, the antenna usually occupies about 3x3m floor area. Here’s my implementation based on Ljubisa Popa – POP  YU7EF design EF0604S.

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