BC-902B schematic?

[Opcom]

Anyone have the schematic for the SCR-241 or more precisely the "BC-902B" transmitter part of it?

All I can find it this:

SCR-241* Instrument Landing Navigational Aid (BC-302, BC-303 and BC-902); AN 08-10-142, 1943 , ; and a reference to 75MHz.

A friend found one in a pile of stuff, saving it for me.. might be a nice 6M AM conversion? I have not seen it yet.

[N0WEK]

That would be a marker beacon transmitter that transmits a tone to a receiver in the aircraft to let the pilot know where he is on an instrument approach, outer marker, middle marker and inner marker.

http://en.wikipedia.org/wiki/Marker_beacon

The improved version is the BC-1332. I couldn't find any info on either one though.

I don't know the power, the Wiki article says 3 watts, but it should transmit on 75 mhz with AM tone modulation.

Good luck with it.

[Opcom]

Here she is!! Not in too gouda shape, but saved the poor thing from being wrecked. Schematic is on the last sheet. A plate-modulated 7C5 as the PA on 75MHz !?!?! (read - a 6V6 at 75 MHz! Yeesh!)
- http://www.bunkerofdoom.com/mil/bc902/index.html

- and also I found this while I was at it, the schematic for the AN/PRM-10 Test Oscillator Set covering 2-400MHz.
http://www.bunkerofdoom.com/mil/prm10/an-prm-10.jpg

- and finally did put all the pig-irons back in the BTA-250. That was a job. Pic attached. Transmitter Porn Alert !!


PJ