Good Morning All, Well, I guess I'm doomed to be "...rockbound" for the time being with my R-4 receiver...
I tried two different versions this past week of homebrewed RF generators, to replace the optional HC-6/U heterodyne crystals at the back of the set for SWL'ing, i.e. a solid state one (MPF-102 oscillator + MPF-102 follower + 2N2222A final amplifier) AND a tube type (12AU7A, half oscillator / half cathode follower) with the following results: -SOLID STATE: nice, fairly clean & steady signal up to around 27-MHz, but far too low in strength / voltage to properly "drive" the R-4. -TUBE TYPE: much stronger signal output, same frequency range as solid state, but very rough sounding tone...made all of the CW signals sound like those homebrewed outfits from the USSR & Cuba back in the 60's. ...So, I guess I won't be terminating my association with Jan Crystals, Les Smith, AF4K, et al, any time soon! Happy New Year to all, & my vy ~73!~ Eddy VE3CUI - VE3XZ
