Amplifiers » DA102

# Manufacturing Process

#

#

#

### 1. PCB Manufacturing / Soldering

Description of the printed circuit board (PCB) manufacturing and soldering process.

1. PCB preparation

2. Component placement

3. Soldering process

4. Visual inspection

📌 Note: Insert photos here showing the PCB manufacturing steps.

#

### 2. Components Assembly

Description of the procedure for assembling the electronic components of the amplifier.

1. Module placement

2. Wiring

3. Securing components

4. Functional testing

📌 Note: Insert images here showing assembly steps.

#

#

## 3. Testing / Case Assembly

#

#

### • Functional test

![](image1.jpg)

1. Visual inspection to ensure that all components on the board are correctly placed.

📌 Note: Check for a missing coil, as this is a common failure point (Fig. 1).

2. Set the HDMOD-1 source (with RF output of 90dB) on channel 21 (474.00MHz).

3. Connect the output to a 20dB attenuator.

4. Measure the PWR level at the output of the 20dB attenuator using the field meter. The desired power value to confirm correct operation of the source before connecting the amplifier is 69dBuV (Fig. 2).

 📌 Note: 90dBuV (source) – 20dB (attenuator) + 36dB (DA102 amplifier) – 1dB (cable losses) = 69dBuV.

![](image2.jpg)

5. Place the amplifier between the source and the field meter, and power it with 12V DC, verifying a current consumption of approximately 270mA (Fig. 3).

6. Set the attenuation and equalizer switches to their maximum position (Fig. 4).

7. Connect the output to a 30dB attenuator (required due to the DA102 36dB gain).

8. Measure the PWR level at the output of the 30dB attenuator using the field meter. The desired power value to confirm correct operation of the DA102 amplifier is 75dB (Fig. 5).

 📌 Note: 90dBuV (source) – 20dB (first attenuator) + 36dB (DA102 amplifier) – 30dB (second attenuator) – 1dB (cable losses) = 75dBuV.

#

### • Case Assembly

![](image3.jpg)

1. Local removal of the Solder Mask (green coating) (Fig. 6) using an appropriate tool, in order to expose the Copper Layer (copper coating) (Fig. 7).

📌 Note: Soldering is performed between the PCB copper surface and the metal surface of the case, as solder cannot adhere to the Solder Mask.

📌 Note: *This step may be omitted in the future with a redesigned PCB.*

2. Tightening of the nuts and placement of the washers, preparing the board for insertion into the metal case (Fig. 8).

📌 Note: The internal nuts should be tightened only until they make contact with the SMT connectors—no additional torque should be applied. The washers must be oriented so that the flat side faces the nut, while the curved side faces the metal case that will be installed in the next step.

![](image4.jpg)

3. Insert the PCB into the metal enclosure, ensuring that the openings where the SMT connectors protrude have the two washers positioned on each side.

4. Place the two metal rods, which hold the PCB at the required height from the bottom of the enclosure (Fig. 9).

5. Solder the PCB to the enclosure using a soldering iron around the perimeter, at the points where the copper layer is exposed, and then remove the metal rods.

6. Tighten the nuts onto the enclosure using slim adjustable wrenches that can fit inside the enclosure (Fig. 10).

📌 Note: The nuts on both connectors must be tightened evenly to avoid bending or deforming the metal surface between them.

7. Install and secure the metal cover (Fig. 11).

![](image5.jpg)

8. Install the metal base and the two side panels (Fig. 12), after first removing the protective adhesive film from the base (Fig. 13).

9. Align and secure the amplifier to the base and side panels, fastening it diagonally with 4 Phillips 3×6 screws (Fig. 14).

![](image6.jpg)

10. Vertically position the metal top cover of the case (Fig. 15), ensuring that the two switches and the LED align correctly with their respective openings.

11. Secure the cover to the main body, fastening it diagonally with 4 Allen 3×6 screws (Fig. 16).

#

### • Network and Spectrum Analyzer test

![](image7.jpg)

1. Connect the input to the output of the Network Analyzer using the appropriate cables (Fig. 17), ensuring that a 20 dB attenuator is inserted in series between the two ports.

Press "PRESET" -> OK

Press "START" -> 100MHz

Press "STOP" -> 1200MHz

Press "MEAS" -> S21

Press "CAL" -> CALIBRATE -> RESPONSE -> THRU -> DONE

Press "DISPLAY" -> NUM OF TRA -> 2

2. For the amplifier measurements, connect its input to the step attenuator, into which the signal from three generators is combined via a splitter, and connect its output to the network analyzer.

3. Set the attenuation and equalizer switches to their maximum position.

📌 Note: For the amplifier, **ALWAYS** ensure to connect the input and output cables before powering the unit.

Press "MEAS" -> S11

4. Identify measurement points at multiple frequency values in order to evaluate the ripple across the response curve (Fig. 18).

Press "POWER" -> PC

📌 Note: Use the mouse to select the dBm field and adjust the value using the ***up*** and ***down*** arrow controls.

5. Ensure that the response curve exhibits a return loss greater than −10dB.

6. ????? (Fig. 19).

Press "DISPLAY" -> NUM OF TRA -> 2

![](image8.jpg)

Press "PRESET" -> AUTO ALIGIN -> OFF

7. Connect the input to the output of the Spectrum Analyzer using the appropriate cables.

8. Set the center frequency to 605.0MHz.

9. Initially, set the attenuator to 0dB.

10. Adjust the width span parameter to 35.0MHz.

11. Manually configure the CPL by setting the RBW parameter to 100kHz and the VBW parameter to 10kHz.

12. Manually configure the AMPL REF LEVEL parameter to -100dBm, set the AMPL ATTENUATOR to 0dB, and select dBuV for the AMPL UNIT.

13. Confirm losses from mixer, filter, and cable = -14dBuV.

#

14. Set the first generator to a frequency of 600.000MHz and the second generator to 610.000MHz. Adjust the RF output level to 100.000dBuV.

15. Initially, set the attenuator to 30dB.

📌 Note: Set the attenuation switch to its maximum position and the equalizer to its minimum position (Fig. 20).

16. Select the peaks of the two "high" Δ functions, via the dial and ensure they are at the same dBuV level.

17. Using the MKR NORMAL and MKR DELTA options, adjust the cursor to the peaks of the two “high” and two “low” Δ functions to measure their values.

18. Ensure that the difference between the “high” and “low” peaks is -60dBuV.

19. Calculate the gain of the specific amplifier (DA102) so that it matches the manufacturer’s specifications (Fig. 21).

 📌 Note: 83dBuV ("high" peak) + 30dB (attenuator) + 1dB (cable losses) = 114dBuV (DA102 amplifier).

#

20. The final step consists of labeling the LOT# identification and completing the product packaging.

#