Ramsey Electronics UAM4, Manual

Page 1: ...le Gain 22dB 25dB 29 5dB 36dB Balanced or Unbalanced High Impedance Inputs Shutdown and Mute Control Integrated Click and Pop Suppression Low 0 1 THD N Current Limit and Thermal Protection Programmabl...

Page 2: ...HF All Mode Receivers DDF1 Doppler Direction Finder Kit QRP Series HF CW Transmitters CW7 CW Keyer QRP Power Amplifiers RAMSEY MINI KITS Many other kits are available for hobby school scouts and just...

Page 3: ...List 10 Pre Assembly 10 Assembly Steps 11 Using Your UAM4 15 UAM4 Schematic 18 Detailed Input Output Information 21 Troubleshooting Guide 25 Neat to Know Info 29 Conclusion 30 Specifications 31 UAM4...

Page 4: ...r are operated in on off mode The term usually applies to devices intended to reproduce signals with a bandwidth well below the pulse switching frequency which is the case of the UAM4 is about 200kHz...

Page 5: ...the schematic pg 18 you will notice a large rectangle in the middle This represents the MAX9708 and aside from a transistor LED and zener diode it is the major active component in the UAM4 The input s...

Page 6: ...ained earlier by converting it to a bunch of pulses and turning on and off the output transistors letting you connect to the speakers and hear the music The speakers are connected to the output termin...

Page 7: ...used to adjust the gain of the UAM4 Below the GAIN jumpers is the THERMAL THRESHOLD jumpers H6 H7 and H8 These set up the temperature at which the actual chip in the MAX9708 will cause the device to...

Page 8: ...n the MAX9708 Again if you want more in depth information about the MAX9708 go to www maxim ic com and locate the data sheet RAMSEY Learn As You Build KIT ASSEMBLY There aren t that many solder connec...

Page 9: ...the key when installing surface mount components Typically the first step after identifying the component is to tin one of the PC traces that will connect to the part Once this is accomplished the pa...

Page 10: ...ion terminal blocks J3 J4 8 3 position jumper headers H1 H2 H4 H5 H6 H7 H8 H9 1 2 position jumper header H3 9 Jumper blocks 1 24awg stranded insulated jumper wire 1 24awg solid insulated jumper wire 1...

Page 11: ...it U1 s connections are actually underneath the package and it is difficult to remove bridges without damaging either the board or U1 itself Call our technical support for information before you atte...

Page 12: ...e left of the board 19 Install 10K resistor R4 marked 103 located between and above the patterns for J1 and J2 on the lower edge of the board 20 Install the 7 5 volt zener diode D2 marked 7 5M on the...

Page 13: ...with connection points facing the edge of board located on the bottom edge of the board 30 3 position terminal block J2 with connection points facing the edge of board located on the bottom edge of th...

Page 14: ...re This wire has an enamel type insulation By applying a bead of solder on your iron and then holding the tip of the wire tight against the soldering iron in the solder bead this insulation will melt...

Page 15: ...type of equipment you are going to use it with and how you want to use it To do this we ll ask you a few questions Based on your answers we can point you to the set up instructions best suited to you...

Page 16: ...speaker terminals Now go to the SELECTING BALANCED OR UN BALANCED INPUT section DUAL 20 WATT MONO OPERATION Make sure there are no jumpers between L and R and between L and R SELECTING BALANCED OR UN...

Page 17: ...att amplifiers you will use only the right channel input in the following steps SELECT INPUT TYPE Based on the above information if your input is an un balanced type continue reading If your input is...

Page 18: ...UAM4 18 UAM4 SCHEMATIC DIAGRAM...

Page 19: ...UAM4 19...

Page 20: ...erent polarity the sound will not be as expected Please refer to the DETAILED INPUT OUTPUT INFORMATION and NEAT TO KNOW INFORMATION Determining Speaker Phase sections of this manual for more detailed...

Page 21: ...a lower maximum current We recommend the SPS183 power supply available from Ramsey but any suitable supply such as a 12VDC car battery or other supply capable of supplying the required current is acc...

Page 22: ...of output at 18 volts When the UAM4 was being developed we used a supply with less than 1 amp capacity and it still gave us plenty of power for initial testing purposes plus helped protect the circuit...

Page 23: ...uts together at the output terminals as damage to the AX9708 may result In mono mode the input is applied to the right channel input Any signal on the left input is ignored INPUT MODE JUMPER CONFIGURA...

Page 24: ...on the UAM4 will turn off the input amplifiers of the MAX9708 but leave power applied to the output stages connected to your speakers In SHUTDOWN mode the power to the output stages is turned off and...

Page 25: ...cted mode is activated from the corresponding input terminal This is normal operation and does not indicate an over temperature condition Do not install jumpers between pins 2 and 3 on all headers at...

Page 26: ...bridges between components and board traces Since most of the components in this kit are surface mount and some are placed very close to each other there is a good possibility a bit of solder has fou...

Page 27: ...put check to see if the 7 5 volts is present Connect a multimeter negative lead to the UAM4 ground and check the voltage on pin 3 of jumpers H1 H2 H4 H5 H6 H7 and H8 If you find there is more than 7 5...

Page 28: ...r kit and it is very easy to tell if a problem occurred in the field or here at the factory What if the OVER TEMP LED keeps coming on If the light appears to come on or flicker with the input signal l...

Page 29: ...oice coil Current in one direction will cause the cone to move in one direction and the opposite direction when the current is reversed To determine which way the cone moves with a given current polar...

Page 30: ...are connected out of phase Simply reverse the speaker wires on one of the speakers and the sound will now be in phase and appear between the speakers CONCLUSION We sincerely hope that you will enjoy t...

Page 31: ...ew terminals Impedance Greater than 10K ohms balanced or unbalanced each channel Gain Selectable 22dB 25dB 29 5dB 36dB Distortion O 1 THD N Modulation Scheme Selectable fixed frequency FFM or Spread s...

Page 32: ...UAM4 32 UAM4 BOARD PARTS LAYOUT DIAGRAM...

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Page 35: ...actory for a full refund less shipping The return package should be packed securely Insurance and tracking is highly recommended A reminder this applies to unassembled kits They must be in the same ne...

Page 36: ...y Publication No UAM4 Assembly and Instruction manual for RAMSEY MODEL NO UAM4 40 WATT UNIVERSAL AUDIO AMP REQUIRED TOOLS Soldering Iron Thin Rosin Core Solder Needle Nose Pliers Small Diagonal Cutter...