Ten-Tec 1253 Assembly And Instruction Manual page 30

4-11. Set the RF Gain and both tuning controls to their middle
positions.
4-12. Slowly turn the Regeneration control clockwise until
you hear a sudden boost in background hiss, or a slight whistle
or actual signals. If this does not happen, proceed to step 4-14.
4-13. If you DID experience the effect of the Regeneration
control described in 4-12, you can now try the Main Tuning to
find various stations in the 6.8 to 8.5 MHz tuning range. You
may wish to study pages 49 and 51 regarding the functions of
the controls, particularly RF Gain and Regeneration.
4-14. If you did NOT experience regeneration as described in
4-12, an initial adjustment of trimmer R6 must be done with a
mini screwdriver or alignment blade. Procedure:
Turn Regeneration control to its middle position
Set R6 fully counter-clockwise
Adjust R6 slowly until the increased hiss or slight
whistle of regeneration just begins.
Turn Regeneration control fully counter-clockwise
and then advance it until regeneration just begins.
NOTE: It is normal for the rotation of R6 to generate loud
crackles and pops. Also, with the circuit board not mounted
inside the receiver cabinet, it is normal to hear some AC buzz
from nearby electrical wiring.
4-15. After you've finished exploring your one-band receiver,
disconnect DC power and speaker, and carefully unsolder the red
wire from the C37 pad near L4. This wire will soon be soldered
permanently to the Bandswitch control board.
1253 - 28