Radio Modification Information

HR2510 Alignment Instructions - (Taken from the Uniden Service Manual)

Alignment of P.L.L. and Carrier Oscillator Portion

1. Test equipment required:

     DC Power supply (13.8V)                 Oscilloscope
     DC Voltmeter                                      Frequency Counter
     Dummy Load (50 Ohm)

2. Preparation for Alignment:

PA SW : Off Mode SW : AM
RIT : Middle Position TX SW : Off

3. Alignment Procedure:

	Preset to:	Adjustment	Remarks
1	Mode : RX, AM SG : 28MHz	L315	Connect an oscilloscope to TP306. Adjust L315 For 6.200MHz +/- reading on the oscilloscope.
2	Ditto	L318	Connect the oscilloscpe to TP304. Adjust L318 for 38.695MHz +/- 20Hz reading on the oscilloscope.
3	Mode : RX, AM SG : 29.6999 MHz	L317	Connect a DC Voltmeter to TP303. Adjust L317 for 6.5 +/- 0.1V reading on the Dc Voltmeter.
4	Mode : RX, CW SG : 28 MHz	L117	Connect the oscilloscope to TP1. Adjust L117 for 10.6950MHz +/- 20Hz reading on the oscilloscope.
5	Mode : RX, LSB	L118	Adjust L118 for 10.6925MHz (-40Hz to +0Hz) reading on the oscilloscope)
6	Mode : RX, USB	L116	Adjust L116 for 10.6975MHz +/- 20 Hz reading on the oscilloscope.
7	Mode : RX, USB	VR111	Connect the oscilloscope to TP5. Adjust VR111 for 38.6975MHz +/- 20 Hz reading on the oscilloscope

Click Here to see Alignment layout

Alignment of Transmitter Portion

1. Test equipment required:

     DC Power supply (13.8V) more than 10A
    AF S.S.G. AM FM (1kHz, 500Hz and 2400Hz)
    RF VTVM                                      Oscilloscope
    DC Ammeter                                RF Power Meter
    AF VTVM                                      Dummy Load (50 Ohm)
    FM Linear Detector

2. Preparation for Alignment:

     VR112 : Clockwise                     PA SW : Off
     VR113 : Counter Clockwise      Meter SW : RF
     VR103 : Clockwise                     MicGain SW : Off
     SWR/CAL : Middle Position      TX SW : Off
     Freq. : 28.000 MHz

3. Alignment Procedure:

Preset to: Adjustment Remarks

1 Mode:USB
No Mod. VR112
Remove the B002(PB-100) from the Main PCB.
Connect a DC Ammeter (+) to TP4, (-) to TP3.
Adjust VR112 for 50mA reading on the DC Ammeter.

2 Ditto VR113 Connect a DC Ammeter (+) to TP4, (-) to TP2.
Adjust VR113 for 50 mA reading on DC Ammeter.

3 1mV Mod. L111 Disconnect DC Ammeter. Reinstall the B002 to the Main PCB.
Connect A RF Power meter to the ANT. jack. Connect a RF VTVM, an oscilloscope and a FM Linear Detector across a RF Dummy Load to the RF Power meter.
Adjust L111 for maximum reading on the RF VTVM.
During this step, set the AF oscillator so that the output is less than 20V.
Repeat this two times.

4 30 mV Mod. VR104 Adjust VR104 for 32.5V reading on the RF VTVM.

5 Ditto VR106 Adjust VR106 so that the carrier leakage at USB and LSB becomes minimum and almost equal.

6 Mode: CW
No Mod. VR103 Connect a SW between Pin 8 and 9 of the ACC connector.
With the SW turned on, adjust VR103 for 21W reading on the Power meter.

7 Mode: AM
No Mod. VR107 Adjust VR107 for 10W reading on the RF power meter.

8 Ditto VR117 Adjust VR117 so that "9" LCD just lights on.

9 1 kHz, 30mV
Modulation VR114 Adjust VR114 to obtain the 85% negative reading on the oscilloscope

10 1kHz, 1mV
Modulation
INDIC: MOD VR115 Adjust VR115 so that "9" LCD just lights on.

11 Mode: FM
1kHz, 30mV
Modulation VR105 Adjust VR105 for +/- 3kHz deviation reading on the FM Linear Detector

12 Mode: CW
No Mod.
Vol. : Max VR116 Connect a AF VTVM across a dummy load (8 Ohm) between Pin 1 and Pin 2 of the ACC connector. With the SW turned on, adjust VR116 for 0.4V negative reading on the AF VTVM.

Click Here to see Alignment layout

Alignment of Receiver Portion

1. Test equipment required:

     AF VTVM                                     DC Power supply (13.8V)
     Oscilloscope                                Dummy Load (50 Ohm)
     S.S.G. AM FM (28.000MHz, 1KHz, 30% Mod. and 50 Ohm Impedance)

2. Preparation for Alignment:

     NB SW : Off                                 Mode : AM
     PA SW : Off                                 Squelch : Min. (Auto SQ Off)
     Beep SW : Off                             RF Gain : MAX
     VOLUME : MAX                         TX SW : Off
     RIT : Middle position

3. Alignment Procedure:

     Preset to: Adjustment                                                        Remarks

1 L101, L104,
L113, L115,
and L105                                 Alignment of sensitivity
Adjust coils for maximum reading of the AF VTVM. (During this step, set the S.S.G. attenuator so that the standard output is less than 0.5W (2v/8ohm)).

2     VR102                                Alignment of Squelch
Set th output of the S.S.G. to 66dB +/- 2dB and squelch to maximum. Adjust VR102 so that squelch just breaks.

3     VR101                                Alignment of S-Meter
Set the output of the S.S.G. to 46dB, no modulation.
Adjust VR101 so that "9" LCD just lights on.

4 Mode : FM
S.S.G. : 1mV
(1.5kHz Dev.)      L401 Adjust L401 for maximum reading on AF VTVM.

5 Mode : AM
Noise GEN.
to the ANT Jack.      L203 Adjust L203 for minimum reading on the AF VTVM.
(Noise GEN. OUTPUT : 50Hz SQ Wave 2Vp-p)

Click Here to see Alignment layout

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