17-03-2018, 05:06 PM
Since the video I've reverted back to phones. I've added a two turn aerial coupling coil placed 6mm in line with the RF tuning coil, one end grounded and the other via a 11pf cap to the centre of a coax socket that has been soldered to the tin can. Connecting it to my FM three element aerial is a revelation, good strong audio now and its pulling in very well with good separation. I'll fit a phono socket for low level audio and connection of the phones so the lid can be fitted to the box, an on off switch may be useful too.
I added some crude stabilisation to the inverter with two 57v zeners across the HT so I'm running 114v HT, no apparent issues with the 1j29b. I may add a second valve and small transformer to drive more modern, low impedance and comfortable headphones, those old ones are sore on the lugs.
I added some crude stabilisation to the inverter with two 57v zeners across the HT so I'm running 114v HT, no apparent issues with the 1j29b. I may add a second valve and small transformer to drive more modern, low impedance and comfortable headphones, those old ones are sore on the lugs.
