New pll receiver (July/2004) Bench KH2026, 160 memories, 4 bands FM,MW,LW,SW,
tuner 5/1 Khz steps, one conversion and in Short Waves covering 5,85 to 15,6 Mhz,
three bands om 40, 30 and 20 meters.
450 Khz oscillator with Z8 mcu, for heterodyne detector cw-ssb signals
+ 10uF
*------------||---------------------------* $:For a correct
| 100nF | tuning to solder
Variable *------------||---------------------------* a capacitor 4,7 -
level carrier | _____________ | 7 pF in parallel
10K / | | | 33 | the 2,2 mH coil
+ 5/6V <----\/\/\/--*---|5 7|----*---||-------------*
To see / | Z86E04 | $ ( | @:For resultin a 250
description | MCU | ( 2,2 mH 33 | ohm of resistance
0V <------*-----*---|14 6|----*-------*---||-----* to solder a 330 ohm
| | |_____________| | | | in parallel 1 Kohm
///// | / @ | ///// logaritmh potentiometer
| 1nF \ 250 |
*-------||------------>/ *----||--------> To coil AM detector,
\ tuner 1-10 pF or near
| +/- 2 Khz
......
Particulars components.
For the power supply control with the KH2026 microcontroller , is necessary to search
the pin collector of second transistor, (under the speaker) near the jack +/- 6V from
external supply.
NOTE: The diameter coil support is 5 mm.
..........
Preselector components........................Encumbered the oscillator, without potentiometer
The preselector is a simple system for better signals (+ 15 db) on the SW band
and the image frequency is attenuated.
\|/ 65 cm original stilus antenna of KH2026 receiver
|
|
| 18 - 22 pF
| *---------||----------------> To input internal circuit ant. KH2026
| | / 120+120 pF
*---*---------||---------*
\ / |
Coil / Variable capacitor |
\ |
/ |
*------------------------*
|
///// To see the particulars in photo
.KH2026 modification
The switch with potentiometer for tuning.........and the preselector with screw antenna tuning
(A simple system to driver a QRP trasmitter with the VCO receiver)
1) To collect with 100 pF the VCO radio frequency signal, to the base of a preamplifier
transistor type 2N2222A in emitter follower mode, (or ic driver) on the receiver.
2) The output signals from (coax 75 ohm) rca plug to driver external rf power amplifier.
3) The tuning is simple; when i wish to send at 7022 Khz in cw mode, set the frequency
of receiver at 7022 on the memory, and for the trasmitter, set a frequency of VCO
7022 Khz in this mode: (7022-450) = 6572 Khz in another memory location.
4) To switch the two memory frequency for to receiver or to send in cw mode.
5) In this very simple system the receiver is always power on, and then it's necessary
more protection and to stop the firsts stages for the radio frequency signal.
But it's interesting the experiment.
Best regards, Emilio ik1wjq.
New pll receiver (July/2004) Bench KH2026, 160 memories, 4 bands FM,MW,LW,SW,
tuner 5/1 Khz steps, one conversion and in Short Waves covering 5,85 to 15,6 Mhz,
three bands om 40, 30 and 20 meters.
450 Khz oscillator with Z8 mcu, for heterodyne detector cw-ssb signals
+ 10uF
*------------||---------------------------* $:For a correct
| 100nF | tuning to solder
Variable *------------||---------------------------* a capacitor 4,7 -
level carrier | _____________ | 7 pF in parallel
10K / | | | 33 | the 2,2 mH coil
+ 5/6V <----\/\/\/--*---|5 7|----*---||-------------*
To see / | Z86E04 | $ ( | @:For resultin a 250
description | MCU | ( 2,2 mH 33 | ohm of resistance
0V <------*-----*---|14 6|----*-------*---||-----* to solder a 330 ohm
| | |_____________| | | | in parallel 1 Kohm
///// | / @ | ///// logaritmh potentiometer
| 1nF \ 250 |
*-------||------------>/ *----||--------> To coil AM detector,
\ tuner 1-10 pF or near
| +/- 2 Khz
......
Particulars components.
For the power supply control with the KH2026 microcontroller , is necessary to search
the pin collector of second transistor, (under the speaker) near the jack +/- 6V from
external supply.
NOTE: The diameter coil support is 5 mm.
..........
Preselector components........................Encumbered the oscillator, without potentiometer
The preselector is a simple system for better signals (+ 15 db) on the SW band
and the image frequency is attenuated.
\|/ 65 cm original stilus antenna of KH2026 receiver
|
|
| 18 - 22 pF
| *---------||----------------> To input internal circuit ant. KH2026
| | / 120+120 pF
*---*---------||---------*
\ / |
Coil / Variable capacitor |
\ |
/ |
*------------------------*
|
///// To see the particulars in photo
.KH2026 modification
The switch with potentiometer for tuning.........and the preselector with screw antenna tuning
(A simple system to driver a QRP trasmitter with the VCO receiver)
1) To collect with 100 pF the VCO radio frequency signal, to the base of a preamplifier
transistor type 2N2222A in emitter follower mode, (or ic driver) on the receiver.
2) The output signals from (coax 75 ohm) rca plug to driver external rf power amplifier.
3) The tuning is simple; when i wish to send at 7022 Khz in cw mode, set the frequency
of receiver at 7022 on the memory, and for the trasmitter, set a frequency of VCO
7022 Khz in this mode: (7022-450) = 6572 Khz in another memory location.
4) To switch the two memory frequency for to receiver or to send in cw mode.
5) In this very simple system the receiver is always power on, and then it's necessary
more protection and to stop the firsts stages for the radio frequency signal.
But it's interesting the experiment.
Best regards, Emilio ik1wjq.