Grant (PC-409) Alignment Instructions



CAUTION: Use isolation transformer or observe polarity when connecting test equipment.
Allow a 15-minute warm-up period.
Adjustments made with 13.8 volt DC input.
Connect low sides of test equipment to ground unless specified otherwise.
Connect 50-ohm dummy load or antenna before keying transmitter.
Connect microphone.
Suggested Alignment Tools:

GC ELECTRONICS:

L36, L38 9091,8728-A,8728
CAI, CT2 8276,5000

L3, L13, LI5 ............. 5009,8728-A,8728

L1, L2, L4 the L10, L12, L14, L19 through L23

L30, L31, L45 through to L48 9440


SYNTHESIZER ALIGNMENT




Test setup Preset to: Adjustment: Notes:
Input of frequency counter through a
47pF capacitor to TP20 (IC1 Pin 7).
Ch. 19, AM   Check for 10.240MHz.
Input of oscilloscope to TP21 (L21 Secondary). Ch. 19, AM L21 Adjust for maximum.

Input of frequency counter to TP21 (L21 Secondary)

Ch. 19, USB

Clarifier Midrange

CT1 Adjust for 33.9765MHz.

Ch. 19, AM

Clarifier Midrange

L23 Adjust for 33.975MHz.
 

Ch. 19, LSB

Clarifier Midrange

L22 Adjust for 33.9735MHz.
Input of DC meter to TP9.

Ch. 40, AM

Clarifier Midrange

L19 Adjust for 3.6 volts.
Input of oscilloscope to TP1.

Ch. 19, AM

Clarifier Midrange

L20 Adjust for maximum.
Input of frequency counter to TP1. Ch. 19, USB  

Check for 34.7665MHz.

Check all channels.
(See Truth Chart for correct frequencies.)

  Ch. 19, AM  

Check for 34.765MHz.

Check all channels.
(See Truth Chart for correct frequencies.)

  Ch. 19, LSB  

Check for 34.7635MHz.

Check all channels.
(See Truth Chart for correct frequencies.)

Input of frequency counter to TP10 Ch. 1, AM  

Check for .790MHz.

Check all channels.
(See Truth Chart for correct frequencies.)

Input of frequency counter to TP3. Ch. 19, USB CT2 Adjust for 7.801514MHz +5Hz, -0Hz.
  Ch. 19, LSB L30 Adjust for 7.7985MHz +0Hz, -5Hz.
  Ch. 19, AM, Transmit L31 Disconnect TP7 and TP8.
Adjust for 7.8000MHz +5Hz.
Reconnect TP7 and TP8.

Input of frequency counter to TP22 (TR9 Emitter).
Ch. 19, AM   Check for 7.345MHz.
Input of frequency counter to
antenna jack.
Ch. 19, AM, Transmit VR5 Adjust for 27.185MHz.




RECEIVER ALIGNMENT


AM Mode



Connect an AC VTVM or AF Watt meter across speaker voice coil. Adjust volume control to obtain a suitable indication. Set generator output low enough to prevent AGC limiting. RF Gain Maximum, Clarifier Midrange, Squelch MINIMUM, NB/AN;- Off, AM

Test setup: Preset to: Adjustments: Notes:
output of signal generator through a
.0luF capacitor to TP23 (FET1 G1).
455kHz, 1000Hz @ 30% modulation.
Ch.19, AM L15,Ll3,L3 Adjust for maximum.
Output of signal generator through a
.0luF capacitor to antenna jack.
27.185MHz, 1000Hz @ 30% modulation.
Ch. 19, AM L10,L9,L8,L7,L6,L5,L4

Adjust for maximum.

If necessary, readjust
L3,L13 and L15.

Input of oscilloscope to TP25
(DI Cathode).

NB/ANL On Inject a 100pps, luSec. Pulse width signal.

Ch. 19, AM, NB/ANL on L2,L1 Adjust for maximum.



SSB Mode



Connect an AC VTVM or AF wattmeter across speaker voice coil. Adjust volume control to obtain a suitable indication. Set generator output low enough to prevent AGC limiting. RF Gain Maximum, Clarifier Midrange, Squelch MINIMUM, NB/ANL Off.

Test setup: Preset to: Adjustments: Notes:
output of signal generator through a .0luF capacitor to TP24 (TR15 Emitter). 7.8005MHz, no modulation. Ch. 19, USB L14,L12,L10, L9,L8,L7 Adjust for maximum output.
Output of signal generator through .0luF to antenna jack. 27.186MHz, no modulation.' Ch. 19, USB L6, L5, L4
Adjust for maximum output.
If necessary, readjust L7,L8, L9, L10, L12 and L14.

 


General Adjustments



Connect an AC VTVM or AF wattmeter across speaker voice coil. Adjust volume control to obtain a suitable indication. RF Gain Maximum, Clarifier Midrange, Squelch MINIMUM, NB/ANL Off, MOD/S/RF S/RF

Test setup: Preset to: Adjustments: Notes:
output of signal generator through
.0luF to antenna jack. Squelch Maximum
27.185MHz, 1000Hz @ 30% modulation.
Output 1000uV.
Ch. 19, AM, Squelch at maximum VR3 SQUELCH RANGE Adjust so that squelch Just breaks.
Output of signal generator through
.0luF to antenna jack.
27.185MHz, 1000Hz @ 30% modulation.
Output 100uV.
Ch. 19, AM VR1 AM SIGNAL METER Adjust for 9 on S scale of meter.
Output of signal generator through
.01uF to antenna jack.
27.186MHz, no modulation.
Output, 100uV.
Ch. 19, USB VR2 SSB SIGNAL METER Adjust for 9 on S scale of meter.



Transmitter Alignment


AM Mode


Connect an RF wattmeter and 50-ohm, 25-watt dummy load to antenna connector.

NOTE: Be sure to check transmit frequency and power on all active channels after alignment of transmitter.

Test Setup: Preset To: Adjustments: Notes:
Input of spectrum analyzer or harmonic meter to antenna Jack. Ch. 19 L36 Adjust for MINIMUM at 54MHz.

 


SSB Mode



Connect an RF wattmeter and 50 Ohm, 25-watt dummy load to antenna connector.
NOTE: Be sure to check transmit frequency and power on all active channels after
alignment of transmitter.

Test Setup : Preset To: Adjust: Notes:
Inject a 1000Hz, IOOmV signal at
mic input.
Ch. 19, USB, Mike gain at maximum L47,L48,L46, L45,L38

Set Villa fully clockwise.

Mike Gain Maximum Adjust for maximum.

Readjust VR11

 


General Adjustments



Connect an RF Watt meter and 50-ohm, 25-watt dummy load to antenna connector.

NOTE: Be sure to check transmit frequency and power on all active channels after adjustment of transmitter.

Test Setup: Preset To: Adjustments: Notes:
Input of oscilloscope to antenna jack.
No signal input.
Ch. 19, USB VR4 BALANCE Adjust for MINIMUM RF.
Insert DC current meter at TP8.
No signal input.
Ch. 19, USB VR9 BIAS Adjust for 25mA.
Insert DC current meter at TP7.
No signal input.
Ch. 19, USB VR8 BIAS Adjust for 5OmA.

Input of RF Watt meter to antenna jack.
Inject a 1000Hz, 100mV signal at mic input.

Ch. 19, USB

Mike Gain Maximum

VR11 SSB POWER Adjust for 11 watts.
Input of RF Watt meter to antenna jack.
No signal input.
Ch. 19, AM VR10 AM POWER Adjust for 3.8 watts.
Input of RF Watt meter to antenna
jack.

Ch. 19, AM

MOD/S/RF S/RF

VR6 TX PWR METER Adjust VR6 so that TX PWR meter agrees with RF Watt meter
Input of oscilloscope or modulation
meter to antenna connector.
Inject a 1000Hz signal at mic
input.

Ch. 19, AM

MOD/S/RF Modulation

Mike Gain Maximum

VR7 MOD METER Adjust audio level to obtain approximately 100% modulation. Adjust VR7 to read in the 100% area on MOD scale of meter.



 

 

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