[Racal] Receiver details

[Brian Goldsmith]

----- Original Message ----- From: "j.foster"
Can anybody give me some brief specs on the Racal RA 7915.


***John and the list.It is very difficult to provide specifications ,brief
or otherwise as the RA7915 was designed to be ,well,a designers radio
receiver.There were  many options and variations available at the time of
manufacture (circa 1970s).It could be ordered with from one up to six HF
channels,up to nine IF bandwidths and types(USB,LSB AM,CW -wide,normal
,narrow,special).The channel crystals were ovenised and operated at 75 Deg.C
with a feedback network to keep the temperature constant.LO frequencies
above 30 Mhz(the 7915 has a 10.7 MHz IF ) are generated by using a lower
frequency hence more stable crystal and then using a PLL/VCO to generate the
necessary LO frequency.There were three different types of RF/preselector
arrangements ranging from broadband to very narrow fo use alongside high
powered transmitters.The 7915 is operable from the front panel or remotely
using 15 Volt level control lines.It has a squelch control,fast and slow
AGC,a 1uV sensitivity for 50mW out etc.
 A really good receiver,but takes a lot of learning about.Designed and made
in Australia by Racal Australia.
                                                          Brian Goldsmith.