[Milsurplus] Oscillator part of BC-684 or BC-604 schematic?

[Mike Morrow]

Ian wrote:

>Would be grateful if someone has a legible copy of one of these schematics
>and could tell me the component values around the oscillator (top left).

For the BC-604:

Grid parasitic resistor  R149 - 50 ohms
Grid bias resistor        R101 - 100,000 ohms
Grid capacitor            C151 - 50 pF
Screen resistor          R138 - 50,000 ohms
Screen bypass           C146 - .003 uF
                                C104 - 500 pF
Plate/screen supply    R118 - 100,000 ohms
                                R157 - 100,000 ohms
                                R158 - 100,000 ohms
Coupling capacitor     C150 - .001 uF
Plate LC capacitor      C105 - 15 pF

I recall that the BC-684 uses the same values, but has some other part number for R157 and R158.

>Also would like to know the tube type - looks like 1619 but the tubes are
>all drawn as if directly heated.

All tubes except the PA tube (1624) are 1619 tubes.  Both the 1619 and 1624 have directly heated cathodes.  See the 1938 RCA data sheet at http://www.mif.pg.gda.pl/homepages/frank/sheets/049/1/1619.pdf .

Mike / KK5F