DIY EDT-2902 Multiband Radio Kit FM MW SW1-7 Amplitude Modulation 9 Band Radio Training Kit

Debugging:
1) FM band debugging:Put the assembled circuit board into the stand.Turn the switch to ON, turn the band selectorto FM, D1 LED light. The first step: adjust the receive frequency range, adjust the quadruple variable capacitor to the lowestend, the standdisplay FM frequency, use a tool to adjust the L103 oscillation coil to make the figure about 69MHZ, then adjustquadruple variable capacitorto frequency display the most high-end, use the tool to adjust the variable capacitor to makethe display frequency at 108.5MHZ or so, repeatedly adjusted to make the FM frequencyinrange 69-108.5MHZ. The second step: adjust the sensitivity, adjust the variable capacitor to about 80MHZ,received a radio and adjust the L102 coil to makethe speaker output maximum sound, then adjust the quadruple variable capacitor to about 106MHZ,received a radio stationand adjust the quadruple variable capacitor Trim frequency selection circuit capacitortomakethe speaker output maximum, repeated the above adjustments to achieve the best sensitivity effect.

2) Debugging the mid-wave band:
The first step: adjust the receiving frequency range, switch the band selector switch to MWposition, D2 LED light. Adjust the quadruple variable capacitor to the lowest end, and thetest standshows the frequency of the middle wave. Use a tool to adjust the T101 oscillation to make itdisplayed at about 515KHZ. Adjust the quadruple variable capacitor to the highest frequency displayport, use tool to adjust AM trimming capacitor to make the frequency at about 1640KHZ, repeated adjustments to make the frequency in the 515-1640KHZ range.
The second step: adjust the sensitivity,adjust the variable capacitor to about 600KHZ, willreceive a radio AM, adjustthe AMANT coil to make the speaker output maximum sound, then adjust the quadruple variable capacitor to about 1400KHZ,received a radio, adjust the quadruple variable capacitorto make the speaker output the maximum sound, repeatedly the above debugging sensitivity to achieve the best results.

3) Short-band debugging:shortwave use a high-frequency amplifier circuitwhichdoesnot need to adjust the sensitivity, need to adjustfrequency.
Frequency adjustment: Afterfinishingthe mid-wave debugging, and then push the switch to the SW1position, make the quadruple variable capacitor to the lowest end, tune T102 (green) shortwave, let itshowthe frequency range of 5.7MHZ, shortwave 1-4 automatic Synchronize. Then push the switch toSW7position, adjust T103(white) shortwave frequencyto makethe frequency is displayed at about 18.5MHZ, shortwave 5-7 automatic synchronization.

4) AM IF Week T104 adjustment:Find a strong signal shortwave radio, adjust T104 (yellow) to make the speaker output maximum and theclearest.

5) Complete the commissioning, push the switch to OFF to turn off the and take down from the stand.
Package included:
1 xDIY EDT-2902 Multiband Radio Kit












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