1. Glam_i0zkz In the following pictures a multiband short- wave regen radio receiver, designed to take advantage of a single multi-function chip for both the high frequency and audio The high frequency "regen" circuit was taken from the website TECHLIB.COM http://www.techlib.com/electronics/regen.html http://www.techlib.com/electronics/regen.html Slow scan: To change the image, click with the left mouse button

2. The regen receiver using a single integrated circuit LM 389. The RF part is pretty much the same as indicated in the original circuit. The only differences are the inductance with antenna coil and 10k gain potenziometer and the supply control of the Q1, useful in some portions of the band to adjust better regeneration. The rest relates to the audio amplifier

3. Components mounting plane in the matrix board with coordinates of the anchors and the directions of the wiring circuit. The red numbers indicate the LM 389’s position

4. LM389 chip data sheet – Note the three transistor before the amplifier

5. The matrix board has already been wired and the first components installed

6. Back side of the matrix board

7. Testing the receiver with the coil above described

8. Interior view: the board with the chip, the coil, the variable capacitor, the band spread capacitor. The inductance is different from that described in the circuit. It was preferred an extended ceramic coils with 5 outlets suitably selected for the exploration of the short wave band. In the lower part the winding antenna of about 15 turns wound above, in the gaps, made with 1 mm, covered telephone wire. The support base of the receiver is wood type "timber decked", 2 cm thick.

9. The wooden support and the front panel al 1 mm. The gear-knob tuning is temporarily mounted without its graduate scale

10. Looking at the receiver from left the matrix board, the coil with the switch bandwidth, the band-spread capacitor, the antenna gain potentiometer under its input jack, the tuning capacitor, the batteries (13.5 volts) placed in the space dedicated to them.

11. Batteries in a composite container made ​​ from sturdy cardboard tetra-pack milk that I will subsequently lined as followed

12. The battery box lined in its final version ready to be fixed to the wood frame

13. Testing the receiver with external power supply and battery

14. The receiver is finished and completed with painted aluminum cover. Note the top of the cover with the slot corresponding to the elliptical speaker. Note the tuning gear-knob with its graduated scale. The grey knob of the antenna gain has been replaced with a smaller black. Note the red clip antenna, black earth

15. The horrors shack, or the hobby room: i0zkz’s radio station On the table two other small self-built receivers and, between the two, the excellent TENTEC Model 1253 9 band regenerative shortwave receiver kit