[SP2ONG]

Modyfikacja mikrofonu BAOFENG UV5-R w celu eliminacji efektu "motorowki" na DMR. Wystarczy dolutować dławik 10 mikroH
Efekt "motorowki" z tym mikofonem bez modyfikacji wystepuje kiedy nie używa się anteny zewnetrznej. W przypadku podłaczenia anteny zewętrzenej mikrofon działa poprawnie.

Opis modyfikacji:

Boafeng RSM
The worst of the RSMs I had on hand was (not surprisingly) a Boafeng RSM. A saving feature of the Boafeng RSM was that it used a large ground plane and ingress was mainly to the non-ground parts of the RSM.
A small modification was made to insert an 10µH choke right near the electret capsule to reduce ingress to the capsule itself.
Above is the modification. The track was cut a few mm from the bypass cap, and the gap bridged with the 10µH choke (which is soldered to both the electret and the bypass cap).
This modification almost eliminates the ‘motorboating’.
Further steps one might explore is effective RF grounded of the electret can (which has its challenges as it is usually aluminium). I will obtain some 0603 10µH multilayer chokes to try in some other RSMs.