ViH, TABLE OF CONTENTS Specifications ..o i R cai Description Accessories Pr-OQperation Control Functions Operation Theory of Operation ool 12 Maintenance and Adjustment er Merger 17 Inside View: 50 ol i nin Dl 20 Voltage Chart .00 o0 oioiiaii G 21 Bloke Diagram o000 0o in 22 Board Flavorful .
SECTION H: DESCRIPTION Congratulations on the purchase 61 the 1C-502A portable 6 meter SSB transceiver. THe 1CA02A was designed to be operable anywhere like most portables, but we also included features found in most base sets Ike 4 very effective noise blanker, RIT, S&RF meter, CW monitor; and 3 full 3 watts: output on USB. A highly stable VFQ allows operation between 50 MHz and S1 Milo.
SECTION I ACCESSORIES Various necessaries are packed with your transceiver; Be sure not to overlook anything, Massasoit good idea to keep packing cartons in case of moving or if return for service is necessary.
SECTION BATTERY INSTALLATION Dy Batteries: Place the mode switch i the: OFF position.: Remove the side: that ‘covers the hatter case and speaker.
Ned, install five nickel-cadmium batteries in the battery tubes in the same direction. Make certain the minus side is next to the spring. After installation of the charger and batteries in the case, connect the connector from the transceiver housing to the socket of the charger. Make sure the switchover thd chargers ON; then install the side cover as before: g AC BATTERY CHARGER: BC-15 Thai: consists: of an: B17/220 Volt AC charger: 10 900mAh camiknickers batteries, and fuse-box.
fused with old batteries the life of new ones might be shortened. Artery life i shortened more by transmitting than by receiving since several times more current is drawn i transmit. To prolong battery life, therefore; practice as follows: Tey to minimize the transmit period. % Reduce volume during reception.
FOR USE IN THE CAR Avid using the Unit near the outlet of heaters, air-conditioners, ¢t 1 2. Install the unit in a convenient place 1o avoid disrupting safe driving. 3. For the best power rouses, connect o the car battery through a fuse (1A2A). 4. Firmly ground to the car body a mobile antenna whip antenna), this I8 required, Cable Connection Connection using 1 C=50 L e duR FOR FIXED USE : 15 Avoid installing the obit in plies exposed to rain; water splash; divert sunshine; dust; Libra: “ton, or heat.
TUNING KNOB Tunes the frequency. RIT Ti dependently swings' the receiver frequency 't kHz so that signal¢ that are slightly off frequency may be tuned for clarity without affecting the transmitting frequency. .. MODE SWITCH In the CW.T position the transmitter will transmit when the CW key makes contact. Tn the REC position both SSB and CW signals can be received. I the CW.T position the microphone is deactivated in the mercuric .
Snapdragon T, M gos g 15 Shoulder Si rap Tracker et Haunting Pt B Atari An Tn Compromises Bury ok 15. SHOULDER STRAP BRACKET Connect the shoulder strap hire for Easy carrying (See page 3) 16. WHIP ANTENNA Extend: completely for operation. When ot in use, the antenna should be fully: collapsed. Use care when extending or collapsing the antenna. MICROPHONE HANGER When not in use, the mike can be hung out ot the way. .
SECTION Vi OPERATION 1. After the batteries have been installed, or the IC-502A i connected to an external source, Furn the function switch ON. If the surrounding light 18 too dim to see the S & SR meter, tum the switch to the LIGHT position, and the meter will be illuminated. Extend the whip antenna to its full length, or if you wish to use an external antenna; connect 'the cable to the FXT antenna connector on the back of the 1C:S02A Connect the microphones fo the MIC connector on the front panel.
CIRCUITS Section X shows a block dissimilar of the 1C-502A, The receiving section 15 a single conversion superintendency with a MHz high-stability VEO as the local oscillator; The transmitting scion is a single conversion system which employs a filter type SSB generator using a 13 9985MHy crystal filter and the same local oscillator as the receiving section. A double-balanced mixer is used for the! transmitting tinker to minimize spurious diatonic.
AGE CIRCUIT Alpert of the 1F signalizes picked up groin the IF amplifier 101 and passes through C68 and Rad 10 be: detected by D12, D13(152473) and DINGOES. When 1o signal iy received, bias voltage i applied to the base of AGC control OB(25C945) through R43. D13 and D14, and the potential at the emitter of Q8 pus to nearly zero. In the presence of a signal, C67, which is connected to Q8 base is first negatively charged because DL s muted on, and so QR 13 muted off.
at the output; Consequently, these signals ure amplified by the transmit 1B amplifier Q12 and pass through the crustal filter; transmit mixer 1C5 and forward as in the 88B mode. Keying is done by the Q12 source and Q13 emitter. THe 800z signal i oscillated by the CR: phase oscillator Q7 (250945 for the CW MONITOR, and fed to the AF oscillator ICI through the Volume Control COMMON CIRCUITS BFQ The BFO s a Cockpits crystallization using Q10(28C945).
When transmitting, RE is grounded by the microphone PTT switch, or mode changeover switch {in the case of CW-T), to make Quest's vise voltage zero and output voltage zero also. Likewise, for the transmit section regulated voltage, the reference voltage of D3 cathode s applied to Q3% {28D355) base through D4(18853), and a regulated voltage of about 9.5V is obtained ab its emitter.
Though the regulated voltage for the oscillator is supplied at a level of about 9 volts from 04 of the AME unit, it is further stabilized by the constant current circuit using Q5(28K19), and Zenger diode: D2(WZUS56) This voltage is supplied to Q1 Q2; and RIT and FINE TUNING circuits (o further ensure sufficient frequency stability.
TRy e ADJUSTMENT OF VARIOUS SECTIONS This set i3 completely adjusted and checked so that it functions correctly. During prolonged use, however, the readjusted condition may be affected by wear of parts, etc. I it is necessary 1o make adjustments at some time to regain specified performance, the following procedures may be followed: Remember that changes in capacitor or coils will be very small if any) Adjustments should not be attempted without adequate test equipment.
Coils Adjustment Connect the watt meter to the external antenna socket, and set the transmit/receive frequency at “50.5Hz”. With the MODE switch turned to connect a Key to the key jack and hold the key down connect ‘the RE voltmeter probe :to: Q13 base and ‘adjust the: egregious 15~ 119 alternately for 3 maximum voltmeter reading. Driving and Final Stage Adjustment Make sure that the power voltage is 13.
S Meter Adjustment Adjust R53 so that ihe S miter indicates zero in the nonassignable condition, Next, with the signal ‘generator output level set at 90dB(u V). adjust the frequency to the receiving frequency! and adjust RSFSR so that the'S meter indicates full scale.
SECTION X VOLTAGE CHART Transistor FET Unit: QN Mode {81 1GH {EL (G 162 (D} 188 Remains 0.28 92515 4 T G 08150008 078 0051 10.007 1 0.005 0.01 E 06 Rgn02Hiies £ MELON Oz T Knievel Main: Qg 1. 0.08 £ 0 08 Ri008 e08 B Qg T 07010008 £ Q10 22000 Q11 0.23 BB 012 1 o 0008008 Qi i 088 120 04 213 Rii0.008 138 138 € a4 R 001 13.8 £ 1§ T DiE 138 & 015 Ro0005 138 E o1 Tlaloc g0 a0 Cw At Ot R IO 134587 02 Multilingual £ oWt Q2. R 07 0045 & a3 T 103 018 1381003 Knit. 04 i 58 13.8 g Cw At 04 # 86 135 a5 T o 10.
