By Matt Krick K3MK
Preliminary checks and adjustments:
1. Connect signal generator to RX antenna jack on channel frequency.
2. Crystal Frequency = Operating frequency - 10.7 / 27.
3. Oscillator Measurements are made on the Red test points, connect negative
lead of volt meter to ground.
4. If PPL-6060 needs complete alignment, preset L111 through L117 as far out
of the cavity as they will go.
Step | Test Point | Tuning Control | Meter Reading | Procedure |
1 | TP201 | T202, T203, L206 | Maximum | Tune T202,T203 and L206 for Maximum meter reading. Repeat this step for Maximum reading |
2 | TP201 | L116, L117 | See Procedure | Tune L116 for Maximum reading then adjust L117 for a dip.
These readings are small so watch carefully. |
3 | Antenna Jack | C213 | See Procedure | Set service monitor or Hand held for Operating Frequency - 10.7 MHz. Tune C213 for the proper injection frequency. |
4 | TP202 | L115, L114, L111, L112, L113 | See Procedure | Apply an on-frequency signal to the antenna jack. Tune L115, L114, L111, L112, and L113 for maximum meter reading. Reduce signal generator output to keep TP202 below 1 volt. |
5 | TP202 | L209, T205 | Maximum | Apply an on-frequency signal to the antenna jack. Tune L209 and T205 for Maximum meter reading.Again, Reduce signal generator output to keep TP202 below 1 volt. |
6 | TP202 | Maximum | Repeat step 4 and 5 to ensure Maximum front end sensitivity. | |
7 | Speaker Output | T206 | See Procedure | Apply 100uV signal with 1 kHz modulation at 3.0 kHz deviation, Tune T206 for Maximum non-distorted audio output as seen on an oscilloscope. Adjust volume to prevent audio clipping. |
Tune points for PPL-6060 Receiver (top view, dual channel version)