Galaxy DX 2547 Service Manual Excerpts
Support, support, support…The Galaxy support department was gracious enough to send the Galaxy Noise Filter schematic with out a request! This is what is missing in most instances these days with large consumer electronics companies.
Their either to big to follow up on details, don’t know were to get the information, or plain don’t care. Another reason for the lack of support for many radios is that the radios are designed, built and documented off shore and shipped directly to the distributor.
The distributor doesn’t understand radio technology nor do they understand end user customer support. All they see is the chance to make higher profits by cutting out the important link between the factory over seas and themselves. Most of these radios end up in yard sales or the trash soon after the purchase.
Sure you can save a few bucks, but what do you do when the thing quits or there is a technical design flaw. Who’s out their to follow up on it. Don’t think the distributor or mail order company will. They’ll drop it like a hot rock and find a new product to make profit on. Not at Galaxy, they support their product 100% and beyond.
To be honest there are a few companies that support their products, but increasingly I see more products that are not supported at all. Have you ever tried to get a service manual for the Uniden Washington base radio? They haven’t supplied them for many years! Need more be said?
Click On Picture For Close-up.
Figure 2-3 Your Transceiver Microphone Schematic.
Figure 2-4 Microphone plug and pin numbers viewed from rear of pin receptacle.
The following information is from the Galaxy DX 2547 Service Manual supplied with the radio.
|REQUIRED TEST EQUIPMENT|
This transceiver has been aligned at the factory and does not require any adjustments at installation. The required test equipment listed is used for the test setup or alignment shown in Figure 4-1 Transmitter Test Setup and Figure 4-2 Receiver Test Setup. This test setup is used in part or total during the following adjustments. Refer to Page 43 for adjustment location.
|ITEM||U.U.T. (UNIT UNDER TEST) SETTING||ADJUSTPOINT||MEASUREMENT|
|RegulatorVoltage||Connect Voltmeter positive lead to power switch.Connect Voltmeter negative lead to PCB ground.||VR701||13.8 VDC|
|VCO||Disconnect ‘short PCB’ from TP7, TP8 and TP9.Set radio to CH 1 AM RX mode.Connect Voltmeter to TP2.||L14||2.5 VDC t 0.1|
|Set CLARIFIER Control to 12 o’clock.Connect Oscilloscope to TP3.||L15||Adjust for max.|
|Connect Frequency Counter to IC3 Pin 8||VC1||10.2400MHz t 20Hz|
|AM Frequency||Set radio to CH 1 AM RX mode.Connect Frequency Counter to TP3.||L20||16.2700MHz t 20Hz|
|USB Frequency||Set radio to CH 1 USB RX mode.Connect Frequency Counter to TP3.||L21||16.2725MHz ± 20Hz|
|LSB Frequency||Set radio to CH 1 LSB RX mode.Connect Frequency Counter to TP3.||L22||16.2675MHz ± 20Hz|
|TX OffsetFrequency||Set radio to CH 1 AM TX mode.Connect Frequency Counter to TP3.||VR7||16.2675MHz t 20Hz|
|AM OSC||Set radio to CH 1 AM TX mode.Connect Frequency Counter to TP5.||L23||10.695OMHz ± 10Hz|
|USB OSC||Set radio to CH 1 USB TX mode.Connect Frequency Counter to TP6.||L24||10.6925MHz t 10Hz|
|LSB OSC||Set radio to CH 1 LSB TX mode.Connect Frequency Counter to TP6.||L25||10.6975MHz:t 10Hz|
|BIAS Current||Set radio to CH 19 USB TX mode.Modulation Off.Connect current meter to TP7(+) and TP9Connect current meter to TP7 (+) and TP8||VR12VR10||50 mA100 mA|
|SSB APC||Set radio to CH 19 USB RX mode.Connect Multimeter to TP7.||VRI7||12.5 VDC|
|SSB TX Power||Connect “short PCB” to TP7, TP8 andConnect RF Power Meter to antenna jack.Set radio to CH 19 USB TX mode.AF signal 30mV, 1 KHz to microphone.Set RF PWR Fully Clockwise.Set MIC GAIN Fully Clockwise.||L40,L42,L43,L44||MAX > 12WSpurious EmissionMinimum.Balance PowerBetween CH1 andCH4O.|
|SSB ALC||Set radio to CH 19 USB TX mode.AF signal 3OmV, I KHz to microphone||VRI3||11.5 W|
|SSB CarrierBalance||Set radio to CH 19 USB TX mode.Set MIC GAIN Fully Counter Clockwise.Connect Oscilloscope to antenna connector.||VR6||Spurious Emission toMinimum.|
|AM TXHigh Power||Set radio to CH 19 AM TX mode.Modulation Off.||VR14||3.8 W|
|AM TXLow Power||Set RF POWER fully counterclockwise.||VR18||0.5w|
|RF PowerMeter||Set radio to CH 19 AM TX mode.Set RF POWER fully Clockwise.Set SWR/MOD/PWR Switch to PWR position||VR9||For a needle readingof “4” on TX PWR scale.|
|AM ModulationMeter||Set radio to CH 19 AM TX mode.AF signal 30mV, 1 KHz to microphone.Set MIC Gain fully Clockwise.Set SWR/MOD/PWR Switch to MOD position||VR16||For a needle readingof 95% on theModulation scale.|
|FrequencyCounter Adjust||Set radio to CH 19 AM RX mode Set CLARIFIER Control to 12 o’clock.||VC1 onfrequencycounterPCB.||Display should be27.1850|
|AM Sensitivity||Set radio to CH 19 AM RX mode.Set RF GAIN Fully Clockwise.Set SQ Fully Counter Clockwise.Set VOL Control at 2 o’clock.Set NB/ANL switch to OFF position.Set TONE Fully Clockwise.Set CLARIFIER Control to 12 o’clock.Connect RF SG to antenna jack Frequency 27.185 MHz, lmV. Mod 30%.||L2,L3,L5,L6,L7,L8,L9,L10||Audio Output > 2VS/N > 10 dB.|
|Set radio to CH 40 AM RX mode.RF SG setting 27.405 MHz.Set radio to CH 1 AM RX mode.RF SG setting 26.965 MHz.||L5,L6||For Balance BetweenCH 1 and CH 40|
|USB Sensitivity||Set radio to CH19 USB RX modeSet VOL Control Fully Clockwise.RF SG setting 27.186 MHz, 0.5uV. Mod off.||L11,L12||Audio Output > 2VS/N > lOdB|
|LSB Sensitivity||Set radio to CH19 LSB RX modeSet VOL Control Fully Clockwise.RF SG setting 27.184 MHz, 0.5uV. Mod off.||L11,L12||Audio Output > 2VS/N >lOdB.|
|NB Adjust||Set radio to CH 18 AM RX mode.RF SG setting 27.185 MHz, 1000mV Mod off.Set NB/OFF switch to ON position.Connect Multimeter to TP1 (D2 cathode).||L1||DC Voltage to max.(> 2.OV)|
|AM Squelch||Set radio to CH 19 AM RX mode.Set SQ Control Fully Clockwise.RF SG setting 27.185 MHz, 2OmV. Mod 30%.||VR4||Adjust very slowlyuntil squelch just closes.|
|SSB Squelch||Set radio to CH 19 USB RX mode.Set SQ Control Fully Clockwise.RF SG setting 27.186 MHz, 20 mV. Mod off.||VR3||Adjust very slowlyuntil squelch justcloses.|
|AM S-Meter||Set radio to CH 19 AM RX mode.RF SG setting 27.185 MHz, 100mV. Mod 30%.||VR1||For a reading of “9”on the “S” scale.|
|SSB S-Meter||Set radio to CH 19 USB RX mode.RF SG setting 27.186 MHz, 100mV. Mod off.||VR2||For a reading of “9”on the “S” scale|
|Main PCB Adjustment Location|
The Galaxy service manual has many more diagrams including circuit board layouts, block diagram and schematics. Only a small sample have been included in this issue to give the reader a feel for how good the manual is. The manual is professional in every way and will be an valuable asset to anyone who works on the DX 2547.
I don’t know for a fact, but judging by Galaxy’s past history, much of the manual will probably be available on their site before you know it. ©CBWI