Voor een NL versie klik hier
For the Basic Mini-Whip Antenna 2016 click here

Enhanced Mini-Whip antenna (0-30 MHz)

New structure

The Mini Whip antenna (see my previous article Mini-Whip Antenna 2016 ) are already made in countless designs and implementations. However, in the practical implementation, it is not always easy to find suitable housing for (outside) assembly. These are sometimes jars, boxes, tubes and other peculiar housings, which then still have to be waterproof. What if we turn the matter? I came up with the idea of ​​the whole to miniaturize some more, so we can use a simpler construction : as a piece of electrical PVC pipe 3/4 " (16 mm) with two sealing caps (for chair legs), where all the Mini Whip retracted can become.
And so was born the Mini-Whip Slimline. It is now much easier to clamp the entire inside or outside with standard 3/4 plastic brackets or clamps.
The concept remains the same, only the prints are adapted to fit directly into the tube. Internally it is 3/4" or 16mm. The Antenna plate is 100mm x 16mm copper  (singe sided) . Capacitors are 220nF or 470nF (MKM or caramic).

  Circuit :

Board layout main-board :

Layout Antenna section and HF Amp

Example of a Build in a PVC tube

Click  picture for a bigger view Slide the main-board + antenna-part in a piece of electrical PVC pipe from 3/4 " or 16mm, (from the Hobby Market).
If the BNC connector does NOT fit in the tube, then it may be better to left it out, and the cable to the power PCB can be soldered directly on the mainbord.
Do not forget, feed the cable through a hole (6mm) in the sealing cap before soldering him to the main PCB.
Board layout power unit :

Layout Power Board

Click  picture for a bigger view The power PCB can also fits in a piece of PVC pipe  (maybe wihthout some BNC connecter) , or in a square alluminium tube. You can wind a piece aluminium foil arround the pipe, and ground it to the cable shield. Again, the BNC connector can be omitted if this is required, and the cable can be soldered directly .
Photo overview :

This antenna board fits into a 30cm piece of 3/4" PVC electrical tube

The Power board needs 6 to 12V DC power with a battery or a 12V Power Wall adaptor

Click  picture for a bigger view The whole part can  fits in a piece of electrical PVC tube of 3/4" or 16 mm . The sealing caps are not present here on the main PCB.
Wanna see a test of this antenna, look on my website HF Mini Whip Antenne.

Downloads:
Board-layouts download here: MiniWhip1.2.zip .
'73 on1bes

mail: on1bes Scarlet.be