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Puxing PX-777 ALIGNMENT PROCEDURE | Radioaficion Ham Radio

Puxing PX-777 ALIGNMENT PROCEDURE

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Puxing PX-777 ALIGNMENT PROCEDURE

Rev : 01

Date : 20060522

1. TRANSIMITTER ALIGNMENT (TEST CONDITION: USE 7.2VDC 1.2A SUPPLY)

NO.

ITEM

ALIGNMENT METHOD (WITH PRODUCTION SPEC.)

REMARKS

1.1

Check LCD

1.

2.

Switch on the power ( SW451), check all segments should display clearly & correctly.

Check the current should be <60mA.

 

1.2

Rx / Tx VCO

1.

Connect a voltmeter between CV test point and ground

 

2.

3. 4.

5.

Check Rx VCO should be 2.2+/- 0.3V on Frequency 161MHz. Connect PTT button to ground.

Check Tx VCO should be 2.2+/- 0.3V on Frequency 161MHz.

Release PTT button. Press and hold the MON button monitor green light will be on.

 

1.3

Tx Frequency

1. 2.

Connect PPT button to ground and select frequency 161MHz Adjust VC2 until Tx frequency should be 161MHz+/- 0.30kHz.

 

1.4

Tx Power

1. 2.

Connect PPT button to ground and select frequency 150MHz and frequency 174MHz

Check Tx power should be <36dBm at Ant point

 

1.5

Tx Modulation

1.

Connect PTT button to ground and Select frequency 161MHz

 

2. 3.

Apply 4mVrms with 1kHz at mic input.

Adjust VR552 until the frequency deviation 2.0k +/- 0.1 kHz and check distortion should less than 5%.

 


Check CTCSS Tone Dev.

4.

And also check if Tx frequency response as below:

 



300Hz = 1+/- 0.2kHz. and 1.5kHz = 3.0kHz +/- 0.2kHz.

 


5.

Select frequency 400MHz with Code 1, 12, 38 , the CTCSS Dev = 0.6

 


Check CTCSS

Freq. Error


+0/-0.15 kHz

 


6.

Select frequency 470MHz with code 1, 12,38, the CTCSS Dev = 0.6 +0/-0.15kHz

 


Check Max. Deviation

7.

Check CTCSS Code 12 should be 100Hz+/-0.2%.

 


8.

Increased mic input signal to +40dB, check max deviation should less than 2kHz and less than 2.5k with CTCSS.

 

1.6

Tx FM Noise

1.

2. 3.

Connect PPT button to ground.

Connect 220uF E.Cap to mic input and ground.

Check FM noise should less than 300Hz at frequency 150MHz and frequency 174MHz.

 

1.7

Current Drain

1.

Connect PTT button to ground and selected frequency 161MHz.

 

at max. Dev

2.

Check Tx current should less than 1600 mA with max deviation.

 

 

2. RECIEVER ALIGNMENT (TEST CONDITION: USE 7.2VDC 3A SUPPLY)

NO.

ITEM

ALIGNMENT METHOD (WITH PRODUCTION SPEC.)

REMARKS

2.1

Check Rx Audio Level

Rated Audio Output Power

1. Set RF generator to 161 MHz and set RF output to -47dBm with 1.5kHz deviation/1kHz.

2. Terminated speaker point with 8 ohm load.

3. Set speaker output level to 1.0V of unit. Check distortion should be less then 3%.

4. Set speaker output level to 1.5Vrms. Check distortion should be less then

4.5%.

5. Set speaker output level to max. Check distortion should <10%.

 

2.2

Check Rx

Audio

Response

1. Set RF generator to 161 MHz and set RF output to -47dBm with 1.5kHz deviation/1kHz.

2. Set speaker output to 1.0Vof unit with input signal is 1kHz as reference

point (0dB).

3. Check Freq. Response : 300Hz =-2 +/-3dB and 2.5kHz = -6 +/-3dB

 


Rx Sensitivity

1. Set RF generator to 161 MHz and set RF output to -47dBm with 1.5kHz deviation/1kHz.

2. Set speaker output to1.0V of unit and decrease RF output level to 12 dB sinad.

3. Check RF output level of RF generator should less than -123dBm .

4. Set RF generator to CH15 with 2.5kHz dev/1kHz.and decrease RF output level to 12 dB sinad.

5. The RF output level should less than -123dBm.

 

2.4

S/N ratio

1. Set RF generator to 161 MHz and set RF output to -47dBm without modulation.

2. Set speaker output to max of unit.

3. Check (speaker output) S/N ratio should be >40dB.

 

2.5

Rx Audio with CTCSS

Check RX Sens. with

CTCSS Check CTCSS

Tone Decoder

1. Select 161MHz with CTCSS Code 12.

2. Apply -47dBm RF signal with 1.5kHz deviation/1kHz and external input of RF Gen with 0.6kHz deviation/100Hz as CTCSS code.

3. A 1kHz signal will be heard from speaker.

4. Set speaker output to1.0V and decrease RF level to 8dB sinad.

5. The speaker should be on.

6. Increase RF output level to -47dBm and change the external input Freq. of

RF Gen. to 200Hz.

7. The speaker should be off.

 

 

3. DC CURRENT DRAIN

(TEST CONDITION: USE 7.2VDC 3A SUPPLY ONLY)

NO.

ITEM

ALIGNMENT METHOD (WITH PRODUCTION SPEC.)

REMARKS


Check Battery Low

1. Set the power supply to 5.1V+/-0.15V. Battery low icon should be flashing.

 


Check Standby Current (squelched)

1. Check the standby current should less than 60mA(squelched).

 


Max . Audio Output

1. Adjust speaker volume to set speaker output level >1 .OVand distortion 5%.

2. Check current should less than 200mA.

 

S.4

Check charging current

1. Switch off the unit. Check charging current should less than 300+/-30mA with 9Vdc/800mA DC adaptor.

 

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