Transponder airspace

[t-bird]

Transponders would be necessary in certain airspaces. Is it not necessary to clearly define the airspaces before they start implementing the use of transponders?

An example that is still not resolved:

The N1 freeway airstrip North of Pretoria.

Per my post on Avcom :
The freeway strip is between PTA GF 1 and FAR 171 . North of Special rules. So I assume 124.8 Mhz. Per Easy plan the freq is 124.4 Mhz. Can lead to some confusion

Boomslangs response :
Freeway is in the PTA GF1 and the frequency is 124.4. It is not north of the JHB special rules it is north of the Wonderboom CTR which is controlled airspace Wonderboom tower 120.6.
The N1 highway is the eastern boundary of PTA GF 1.

I admit that it is not North of spes rules , but north of Wonderboom. But the boundary for GF 1 is definitely not the N1.

There is no map available that shows that the PTA GF’s border is the N1 highway. I have checked , Jeppersons, Easyplan, and government maps.

Does anybody have an answer with a reference to a Notam , Map or any other publication ?

The problem is that the flight schools enter 124.8 MHZ low level beating up the runway and transmitting all the way on the GF’s freq.

Link to avcom
Avcom / Microlights / No calls by Microlight