The layout of the BFR91-BFR96(S)-2SC1971 6 Watts FM broadcast (87,5-108MHz) Profline
Broadband RF-amplifier has been created with sPRINT Layout v3.0.
You can get a Shareware copy at: http://www.abacom.de
The pcb outline is: 85 x 55 mm (width x height), bitmap resolution is 600dpi.
Use FR-4 double sided photoresist epoxy pcb material for best results.
(*) When printing the layout, be sure to resize it!
Design (C)2005 Rdvv, The Netherlands.
Rework (C)2006 by Helix. The Netherlands.
Intitial 2SC1971 microstripline design (C)2002 Sotiris Papadimitriou/ASPiSYS, Ltd. Greece.
(That should cover it!)
BFR91-BFR96(S)-2SC1971 6 Watts FM broadcast (87,5-108MHz) Profline Broadband RF-amplifier
All component values are drawn on the .comp and .silklayer bitmaps, with the following
1.- mount a ferroxcube bead (3 mm diameter, 5 mm length) over one of the wires of the 56E
resistor (i.e. the wire wich is connected to the base of the 2SC1971 rf-transistor)
2.- the 1uH and 4.7uH coils are ready-made molded type coils.
3.- resistor values are in Ohms, 0.25watts (carbon or metalfilm).
4.- the 47E adjustable resistor measures 10mm diameter, vertical mount (Piher).
5.- all capacitor are ceramic except the 10nF and 100nF ones, these are multilayer types.
6.- the two trimmer capacitors are 22pF, Green (Philips).
7.- the two 150E resistors (at the collector of the BFR96(S) are mounted vertically.
(I) make sure to mount the rf-transistor on a appropriate heatsink and use some thermal
heatsink compound between the flange of the rf-transistor and the heatsink or cabinet!
(Thermal resistance heatsink at least 6°C/W.)
(II) all parts are soldered directly on the toplayer of the pcb.
NOTE: on several places connect the groundplane (bottomlayer) to the groundplane on the
toplayer, choose at will.
(C)2006 Helix. The Netherlands.