Slim-Jim Antenna

      Just completed my slim-jim antenna last week. The materials used are 14 SWG copper wire from old electrical cable and some old PVC's and PVC Connectors. I used a 1.9 Meter 1/2" PVC to assemble element and 1'' PVC for covering the element with an PVC end cap on top and an so239 connector at the bottom end to connect the feeder.

      I used a RG 58 feeder cable and a small balun at the antenna feeder end. And here it is at my roof top. The calculation for element length can be found in google. Do consider a parasitic effect due to PVC and build the antenna with a tuning frequency slightly greater than the required tuning frequency.

Balun for 145.000 MHz.

Cheers !!! ...

Baofeng UV-5R External Mic and PTT

     Here is the simplest circuit or just a setup to interface external condenser mic and a PTT switch to a UV-5R VHF transceiver. This setup can be used by those who wish to make a base station with fixed external antenna using UV-5R. Gain of the mic can be adjuster varying the bias resistance R1. I chose a 5KOhm which works good for me.

      The Speaker and Transceiver can be kept in a single unit like a shielded or unshielded box. An extension cable (2+1 audio grade Shield Cable) with 3.5mm plug on both ends can connect these two circuits. No external power supply is required for this circuit and can be build from scratch.

      Here is my setup using some old PVC's and the PVC connectors as these materiel are easy to source. Just build it so simple from junk... :)

Cheers!...