Customizing the AGC speed Last update 2007-11-12

In the JUMA TRX2 there are two AGC speed (fall time) alternatives, the SLOW and the FAST. These can be selected in the CONFIG pages (by long pressing the CONFIG button). The default SLOW AGC is set up for comfortable "week end type" chat QSOs. If you prefer faster AGC you can select the FAST AGC in the CONFIC pages. The FAST AGC is approx. six times faster than the SLOW AGC.

Additionally you can customize the SLOW and FAST AGC fall times by changing the corresponding resistors on the Main board. The resistor R47 (4M7) defines the SLOW AGC time. If you prefer faster SLOW mode, you can replace the 4M7 resistor with a suitable lower value. If you halve the resistor value the decay time will be haved. If you like, you can try values of 3M3, 2M2 etc. or solder another resistor in parallel with the R47. The resistor R67 (in parallel with the R47) defines the FAST AGC time. Thus the FAST AGC can also be customized by changing the value of the R67, if desired.

A detail of the AGC circut in the main board