Check the listing for details. (Schematic Only) 807 Regenerative Receiver AM + Shortwave (200 khz to 17.5 mhz). Condition: Open box. Listed at 24.00 USD. Schematic only of this 807 Regenerative Receiver. No construction manual is provided, but the schematic shows all component values, including coil data. This circuit is quite similar to the 1625 Regen Radio that I have on another listing, but this one employs two 807 tubes, plus a one transistor amplifier for increased audio gain. Continuous coverage on receiver, from about 200 khz long wave, up to 17 plus mhz. I have sometimes pushed this circuit up to even 18 mhz, but once you pass 17 to 18 mhz things get a bit iffy. So I promise 17.5 mhz on the top end and hope for a bit more. The radio requires hi-z headphones, of the 2 to 4k ohm variety, either the old standard induction type or something of the hi-z piezo variety. Either will work. Two dc voltage feeds are needed, one at 12 to 14 volts dc, at about 1 amp capability, and a second dc source of 12 to 30 volts for the plate circuits of the 807's and the transistor audio amp. The latter power source will only require a capability of a few hundred milliamps. Regenerative receivers will virtually always sound best if powered with a battery source. However, a well filtered bench power supply will also work fine. Controls are main and fine tuning, antenna coupling and a reaction/regenerative control, which also has the power on/off switch. I guarantee this radio will work if wired correctly, and hooked up properly with appropriate power supply and a good antenna system. Mailing schematics to the US only.