manualshive.com logo in svg

Alpha Radio 87A, Operating Manual

Share
Download
Alpha Radio 87A Operating Manual Download Page 40

 

 

         Page 

40  

 

 

 

 

 

 

 

 

 

 

      Alpha 

87A 

User 

Manual 

Rev 

2.0 

 

Summary of Contents for 87A

Page 1: ...her property rights covering the subject matter in this document The furnishings of this document does not give you license to these patents trademarks copyrights or other intellectual property except as expressly written in any license agreement form Alpha Radio Products 6185 Arapahoe Road Boulder CO 80303 Phone 303 473 9232 Fax 303 473 9660 Read this entire manual and all other publications pert...

Page 2: ... AlphaMax Operating Procedures 23 ALPHAREMOTETM Software 25 SAFETY 26 AlphaRemote Operating Procedures 27 Installing the AlphaRemote Software 28 How to Operate the 87A 31 Step by step Procedure 31 Pre Tuning Procedure 32 Protective Functions and Faults 35 Soft Faults 35 Hard Faults 36 Fault Codes 37 RS 232 Serial Communications Link 41 Communications Link Set up 42 Serial control lines 42 Remote C...

Page 3: ...rton holds the power transformer and weighs 43 pounds the second carton contains the amplifier and weighs 42 pounds Safety Installation and Operation The Alpha 87A is designed to meet international safety standards and FCC regulations However one should always remember that the equipment works with high voltages that are LETHAL This operating manual holds information cautions and warnings that mus...

Page 4: ...the way so the interlock can close 3 Insure that both tubes are solidly seated in their sockets with the red silicone rubber chimneys firmly seated against the chassis 4 Connect the green conductor in the Alpha 87A power cord only to the power source neutral or ground Connecting the green wire to a hot line is almost certain to cause immediate damage Triple checks your wiring before plugging in 5 ...

Page 5: ...and current at various points in or on your antenna can actually be many times these values On a simple dipole with sharp wire ends corona localized ionization can easily occur Corona can and has lead to fire in nearby objects Traps in beams and verticals can heat up significantly during high power operation Instances of melting or flashover of traps have occurred in many installations where insuf...

Page 6: ...rly designed consoles can result in outlet air being drawn back into the amplifier air intake and recirculated getting hotter and hotter resulting in degraded amplifier performance or even failure If you are designing your own console consider putting in additional fans and or ducting to deal with waste heat Try to minimize the possibility of dust or other contamination getting drawn into or falli...

Page 7: ...usted carefully according to its manufacturer s instructions This typically is done with a knob labeled DRIVE IC 781 FT 1000 PROCESSOR OUT TS 940 TS 950 or on SSB when speech processing is not in use MIC or MIKE 2 The ALPHA 87A faults into STBY or OFF when unsafe operating conditions occur If this happens record which SEGMENT LEDs are flashing to indicate a BCD fault number and refer to manual sec...

Page 8: ...t is important to use a good lightning arrestor and it is good practice to disconnect and ground antenna feed lines and to disconnect A C power when the equipment is not in use 6 Never use an automatic antenna tuner into or through the Alpha 87A This will cause damage to the input wattmeter input relay Page 8 Alpha 87A User Manual Rev 2 0 ...

Page 9: ...rogrammed to optimize operation with VSWRs up to 2 1 on non amateur frequencies and at various power levels Capable of full CW break in QSK and all digital modes when used with any appropriate transceiver All front panel functions plus numerous other diagnostic and control functions are accessible via its RS 232 communications port Protective functions built in The microprocessor based control sys...

Page 10: ...y fan for extended RTTY or other locked key service This is available separately from Alpha Radio Products Capable of no more than 150 watts into a 50dB load in bypass mode Page 10 Alpha 87A User Manual Rev 2 0 ...

Page 11: ...SWR 1 5 1 within amateur bands 2 1 elsewhere Tube Complement Two Eimac 3CX800A7 triodes in grounded grid T R System Heavy duty PIN diode switch capable of feed through and hot switching of 150W exciter power Switching time approximately 1ms Enclosed mechanical bypass relay ALC Grid current derived 10V maximum adjustable gain Harmonic Output Better than 50 dB below rated output Intermodualtion Bett...

Page 12: ...Page 12 Figures 1 3 Transformer Installation Alpha 87A User Manual Rev 2 0 ...

Page 13: ...an must be installed 4 4 Connect the proper internal line voltage tap The ALPHA 87A may be operated from any AC power source of 190 250V 50 60 Hz 20 ampere capacity It is advisable to check the actual voltage at the connector you are going to use for the Alpha 87A Use an accurate meter such as a DMM set to AC volts A 4 terminal barrier strip for tap selection is located atop the AC module to the l...

Page 14: ...s pieces of shipping materials One of the transformer s connectors plugs into the AC power module near the top rear of the chassis center partition on the power supply side Another connector plugs into the low voltage power supply board which is immediately in front of the transformer near the chassis floor A third HVAC connector plugs into the HV board in front of the transformer and up high See ...

Page 15: ...Page 15 Figure 4 Inside Top View Alpha 87A User Manual Rev 2 0 ...

Page 16: ...Page 16 Figure 5 Front Panel Lowered Alpha 87A User Manual Rev 2 0 ...

Page 17: ...Page 17 Figure 6 Inside Front Panel Alpha 87A User Manual Rev 2 0 ...

Page 18: ...Page 18 Figure 7 Rear Panel Alpha 87A User Manual Rev 2 0 ...

Page 19: ...icators correspond to these band segments as detailed below BAND or SEGMENT buttons are not used during routine operation because the ALPHA 87A automatically switches bands and tunes up if necessary upon application of RF drive BAND and SEGMENT buttons may however be used before applying drive to avoid the brief amplifier bypass which occurs during automatic band change with drive applied When a n...

Page 20: ...seeks first the nearest user segment centered within 50 kHz of the drive frequency 10M 200 kHz then such a factory segment If neither exists it selects the nearest segment 5 7 DEFAULT button May be used to override automatically selected user tuneup data for a segment and instead default to factory data 5 8 ENTER button Used in conjunction with SEGMENT buttons to memorize user tuning data See Sect...

Page 21: ... common phono RCA type plug and the other end with a connector suitable for the transceiver See transceiver manual for transceiver connections The voltage at the relay jack is 5V at 1mA this is acceptable for most modern transceivers The T R relay contact must close before application of RF drive 87A protection circuitry prevents hot switching with RF drive applied Modern transceivers have the pro...

Page 22: ...Page 22 Alpha 87A User Manual Rev 2 0 ...

Page 23: ...tects the onset of non linearity It quickly re adjusts loading and tuning to avert flattopping and splatter while maximizing power output No other amplifier vacuum tube or solid state can do AlphaMax Operating Procedures Function The AlphaMax firmware upgrade enables the Alpha 87A to automatically optimize itself for changes in drive level or antenna impedance This allows the amplifier to re tune ...

Page 24: ...haMax hunt for the proper settings for more than 80 tries and then shut off This is a problem with the transceiver and the transceiver should be repaired It is advisable to store different default values for a given band and band segment as a better starting point for the algorithms to find an optimized value in situations where the autotune gives up after 80 iterations Autotune operation may be s...

Page 25: ...ouch of a button but we don t think you ll want to turn it off And it s easy to install in any 87A a qualified technician can do it in about 15 minutes NOTE AlphaMax can be used without AlphaRemote see below However AlphaRemote REQUIRES the installation of AlphaMax first AlphaRemote utilizes new commands that are only available in the AlphaMax ROM upgrade ALPHAREMOTETM Software AlphaRemote is new ...

Page 26: ...hin the amplifier but it is always prudent to short the high voltage to ground in the area of the tube plates or the plate RF choke with an insulated screw driver as an extra precaution 3 Do not attempt to test the modifications with the cover removed since the built in interlocks will not allow the amplifier to be energized 4 Do not defeat the interlocks as a means of testing the amplifier with t...

Page 27: ...OK and READY indicators Band and Segment selection is made with pull down menus by left clicking the mouse and selecting the desired band and segment AUTO TUNE AlphaMax firmware can be engaged by clicking on the AUTO button If the autotune disengages the text display will notify the operator and the AlphaMax firmware can be restarted by clicking on the AUTO button again or by simultaneously pressi...

Page 28: ...agraph 9 below Click OK to save the selected parameters 7 If you have more than one 87A then select another amplifier to configure or click OK to close the CONFIGURE window if you are only setting up one 87A The AlphaRemote window will open showing status and operating parameters of the selected 87A amplifier s 8 The front panel controls of the amplifier are duplicated in the AlphaRemote window Bo...

Page 29: ...t the desired configuration by clicking and holding down the left mouse button while the pointer is touching either the lower left or lower right corner of the current display and dragging the display into the desired format Page 29 Alpha 87A User Manual Rev 2 0 ...

Page 30: ...Page 30 Alpha 87A User Manual Rev 2 0 ...

Page 31: ...king 12 and 10 meter coverage Step by step Procedure a Press POWER ON button set mode switches to HI and OPR b After the red WAIT tube warm up LED extinguishes the OPR LED will light Apply 10 25 watts of excitation on the desired operating frequency c Automatic band change and tune up when necessary require only about one second during which time transceiver output is by passed directly to the ant...

Page 32: ...ists it selects the nearest segment The basic approach to user programming is to use the TUNE meter function to pre adjust tuning and loading at the desired frequency for amateur use preferably the center of a factory segment with the actual load Then fine tune to peak output power and finally save the resulting tuning data in amplifier memory 7 3 Pre Tuning Using the TUNE Meter The goal for 1 5 k...

Page 33: ...If bad user data is entered for any segment factory data may be substituted by selecting the segment pressing DEFAULT ENTER and then the segment button again 3 Arrows up or down under TUNE buttons indicate increase or decrease tuning capacitance respectively 4 Arrows under LOAD buttons indicate up greater or down lighter loading Increased loading moves the TUNE LED to the right decreased loading t...

Page 34: ...Page 34 Alpha 87A User Manual Rev 2 0 ...

Page 35: ... caused by two conditions 1 Improper operating conditions usually overdrive and possibly excessive plate or grid current high load VSWR or improper T R control cable connections or timing 2 Abnormal amplifier conditions e g low bias which may result in damage in the OPERATE mode When such a condition occurs the control system automatically switches the amplifier to STANDBY The FAULT LED lights and...

Page 36: ...use of the hard power off fault is corrected simply press the ON button The fault code will then be displayed on the SEGMENT LEDs for 30 seconds during warm up and then clear automatically You must not turn off the power before the fault clears or it will log another hard fault the next time the power is turned on Six of the SAME hard fault shutdowns over ANY period of time with no other kind of H...

Page 37: ...Hard Plate voltage abnormally high 7 o o Soft Cathode and or power PIN diode back bias 109V not switching to the required low level with key down 8 o o o o Soft Transmit PIN diode back bias below minimum required value key up 9 o o o Soft Transmit PIN diode forward current below minimum required value key down 11 o o Soft Transmit PIN diode forward current exceeds maximum limit key down 12 o o o S...

Page 38: ...g 24 o o o Hard System voltage fault High voltage 15 volts or 109 volts below safe operating level 26 o o Soft RF drive before or without amplifier keyed possibly mis sequenced T R or attempted automatic band change with excessive RF drive 29 o Soft Attempt to transmit on invalid frequency such as above 24 MHz without unlocking 24 30 MHz coverage 31 Soft Excessive grid current above 100mA continuo...

Page 39: ...cutive times without one successful power up Call Alpha Customer Support at Alpha Radio Products for advice if this occurs This fault protects the amplifier against repetitive abuse and cannot be cleared with user controls Warranty will not apply to resulting damage if this fault is reset by user without factory authorization Alpha 87A User Manual Rev 2 0 ...

Page 40: ...Page 40 Alpha 87A User Manual Rev 2 0 ...

Page 41: ... will open another box called COMx Properties Going down the list select Bps 4800 Data bits 8 Parity NONE Stop bits 1 Flow control NONE Click OK to close the window Now pull down the FILE menu and click PROPERTIES Click the SETTING tab and then click ASCII SETUP at the bottom of the window Click the box for Echo typed characters locally it could have a check in the box Click OK to close both windo...

Page 42: ...or Terminal DB 25F To DB 25 M DB 9 M Pin 2 TXD Pin 2 Pin 3 Pin 3 RXD Pin 3 Pin 2 Pin 4 RTS Pin 4 Pin 7 Pin 5 CTS Pin 5 Pin 8 Pin 7 GRD Pin 7 Pin 5 Make no connection from pins 9 22 12 13 or 14 of the DB 25 F connector on the ALPHA 87A to the computer or terminal These pins are used for baud rate and diagnostic modes of the unit Optional baud rate select Baud rate Pin 12 Pin 22 Pin 9 9600 Low Low L...

Page 43: ...Page 43 150 Open Open Low Default 4800 Open Open Open Example To set baud rate to 9600 tie pins 12 22 and 9 to pin 7 signal ground View of Male Connector pin end Alpha 87A User Manual Rev 2 0 ...

Page 44: ... Reports up to eight most recent soft faults STAT Reports unit status state warm up standby or operate HV mode low or high 24 30 MHz enabled or disabled panel enabled or disabled frequency last entered band last selected segment last used tune and load capacitor positions VER Reports version of firmware installed ON mode commands BAND Reports current band setting band 1 for 1 8 MHz through band 9 ...

Page 45: ...Sets multimeter to TUNE mode reports value MODE Reports current HV power supply setting HI or LO MODE HIGH Sets high voltage power supply to high mode MODE LOW Sets high voltage power supply to low mode OPER Reports whether in operate or standby OPER OFF Sets to standby mode OPER ON Sets to operate mode if ready PWR Reports current forward power out in watts REFL Reports current load reflected pow...

Page 46: ...Page 46 Alpha 87A User Manual Rev 2 0 ...

Page 47: ... output may vary widely from band to band and mode to mode unless the transceiver internal ALC drive level also is adjusted carefully according to its manufacturers instructions Typically this is done with a knob labeled DRIVE IC 781 FT 1000 PROCESSOR OUT TS 940 TS 950 or on SSB when speech processing is not in use MIC or MIKE ALC Automatic Level Control is a system used in transmitters which is s...

Page 48: ...nsceiver peak RF output in CW or SSB as close as possible to the power level approximately 50W needed to drive the amplifier to 1 5 kW b Switch the amplifier to OPERATE and while driving it as above turn the ALC pot counterclockwise CCW as far as possible without exceeding amplifier grid current of 50 mA With some transceivers e g recent ICOMs this pot setting may be only a fraction of a turn cloc...

Page 49: ...µf across the switch contacts normally cures the problem Use the smallest value that works 2 Repeated high or low voltage hard faults e g faults 1 6 Is the primary voltage tap correctly set See section 4 3 Is an AC line unusually high or low or regulation bad Check wiring 3 Overtemperature fault 21 Are air intake rear panel and exhaust above tubes openings clear of obstructions A log book lying on...

Page 50: ...Page 50 Alpha 87A User Manual Rev 2 0 ...

Page 51: ...The following block diagram emphasizes the principal functional components as follows Heavy rectangular boxes represent individual modules of the amplifier in most but not all cases circuit boards PCBs a Signal paths used in both transmit and receive are shown by heavy solid lines b Signal paths used only in transmit by heavy dashed lines c Signal paths used only in receive by heavy dotted lines d...

Page 52: ... TX RF out RX RF in jack output wattmeter output T R PCB input T R PCB input T R PCB tube deck T R section and input wattmeter to the TX RF input jack which is of course also the RX signal output to the transceiver RS 232 communications port This 25 pin connector and wiring to it is located at the lower left corner of the block diagram SchematicsAvailable One set of current Alpha 87A schematics wi...

Page 53: ...llation 12 4 Inside top view 15 5 View with front panel lowered 16 6 Front panel view 17 7 Rear panel view 18 8 Examples of AlphaRemote screen configurations 28 9 ALPHA 87A Functional block 55 10 ALPHA 87A Simplified schematic 56 Alpha 87A User Manual Rev 2 0 ...

Page 54: ...pha Radio Products will furnish a new part in exchange for any covered defective part or if it is determined that factory service is required will authorize return to factory Equipment authorized for return shall be shipped to Alpha Radio Products fully prepaid and insured USING ONLY FACTORY APPROVED PACKING REMOVE POWER TRANSFORMER BEFORE SHIPPING ANY UNIT WHICH WAS ORIGINALLY SHIPPED FROM THE FA...

Reviews:

No comments

Brands by name

Popular brands

Load more brands