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Ge 35825b Service

A3-5825B General Electric

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611 views12 pages

Ge 35825b Service

A3-5825B General Electric

Uploaded by

paulvk3mr
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
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MODEL 358258 GENERAL Gi) ELECTRIC DESCRIPTION OF TRANSCEIVER CIRCUITS RECEIVER CIRCUITS. IF 3 SSB DETECTOR- The signal from T207 1s coupled to the eo ep) thru 6279, 1208, D2, R98, HXF=1 (a & 558) (Fitter). and R34, Tne steep side skirix of the anp- 8 Mitudewverses-frequency response curve of the f11ter RE_STASE- An incoming iigna’ fron the antenna Jack-{J1) (wXF=1) helps elimate adjacent channel interference and fs coupled to the base of 209 (RF Anp) thru AMI warning — teproves selectivity. TZ02 1s peaked tuned to 10.6567. Eireutt L214, C262, C263, and T206. Transformer (1205) The amplified signal from Q7 1s coupled to the baze of OS in the base circuit of (209, 15 broad tuned to 2782. thru T3, which {3 peated tuned to 10.6935%K2. The output When used in sone versions; D212 and D213 provide over- - . of Qa 4% direct coupled to the base of Q9. The output of Joad protection. and Q224 grounds the signs) fed to 1206” O9 4s developed across Td, which 43 tuned for 10.6935H2. fn transntt, The RF anolifier stage provides sensitivity The signel ig coupled thrs C44 to the base of Q10 (SSB and Voce) osctHlatar tsolatton. DET). “QUO (SSB UET) combines the RF SSB signal at the base’to the carrier signal at the enitter. The carrler HOXERS_(AH)- The arplified signa from the collector of signal comet from G3 (Ose 3) and thru G4 (Buffer) & developed across 1205, which ts peaked tuned to frequency af 10.6950 in USB and 10.692Mi in LSB, The 27Miz. The signa) 1s coupled to the base of 210 thry detected output of 19 4s an audio signal which 1s 235. and T204, which 13 peeked tuned to Z7Hiz. The coupled thru’ C47 and R43 to the audio Tine. Signal at the base of 0210 4s mized with local oscitlator COED Signal (37.6602 - 38.10008i2) from the frequency sym AGC-(SS8)- An RF sgnal fron 99.18 coupled to the gate of ‘thestzer to produce the 10.6952 first intermediate “AGC)." From 09: thru C43 toa voltege doubler frequency. “The signal {5 coupled thru C279, T200. R24 consisting of DIZ, 013, and:CS1. As''the signal: increases WHF-2 (Filter), and R25 to base of Q5 from 1207. Trans. the. voltage doubler: decreases the bias on QI1,. thus formers 120? and 7208 are peaked tuned to 10,6950012. "The geeeertestese bine Sea eet or G7 (Sem gE hed) enO8 (RE signal at the base of QS (Second Mixer) 1s mixed with Sap) and G2IO {iferds. the AEC Tevel. f3, determined be Tos24a#is to produce the ASSuAz second tntermediate adjustment of AVE (SSB AGC) (See Alfgnsent Instruc~ frequency. The 455kAz 4s developed across TH, tuned to Yona). “nva'ts adjusted for ete audio Sutpet wiak Asse. Aigrala fron S0.Y to 50,0004. JE_B DETECTIR (J8)- The 45StiHz totermediate Frequency” SOUL FETER (S5B)- De rectffies the SS8_IF signa) and Tram tae Seccnliy of Tis coupled taru CE fitter ona f° {POULPETEL G38)- DE recttttes the SSELTF sional R30 to 6 (A IF Aap). The steep sided shirts of the d STEUL:POMER Meter (R)c -RVA (SSM SIO METER ADIUST) 13 anol itude-versur-frequency respenso curve of the f11yér sdjusted tor "9" reading, with a TOD signal at the CF helps eliminate adjacent channel interference improves selectivity, The arolified output fran 06) ts 2 » coupled to the bate of QB thru C28 and T3. The SSB IF couric (4M RSSB)- The'hignals applied to the bise of Srenstorens AsTarieibe C#tPUt: OF Q0) 18 direct couples te: EE Suto es fron 017 (Providing AM AGC) and fron 016 to antenna connector. (J1). the base of 09. The amplified output of OS ts coupled to Perth ashe Oe ee D10 thru T4 and 12, T4 4s 2 $58 IF transformer. Trams- gosiied to. the base of GIS overcones the bite. proviced by, former Tz 1s peak tuned to 455Wiz. The detector diode Ps ¢Sqrcctnt bate of US overcomes, the Bias pray DIO rectifies the negative envelope of the podulated 1F Conduct ‘Mnen n-Ssiiwode the voltege upplied te the Signal and C36 shunts the 455kHz to sround, leaving the base Gf 015 overcones: the bles proviced by Vi2, RV7, and Gatacted audio at anegative DC level, RYIO (SSB SQUELCH RANGE), O15 wil] conduct. The con~ a duction of O15 forward’ biases: G16 (SCUELCH). 16. back AGC _(AN)- A voltage divider network consisting of ROZ, biases O17’ (SQELOH), which allows: IC2 (AF inp) to BESE eke tdtada sets up ee epeaees Ae level. "The operate. However, when the bias supplied to the base of detected audio causes a reverse current to flow thru R53, “G15 4s fot sufficient to overcone the enitter Bias. QI R56, DIO, and T2 secondary. This reverse current causes’. 13 biased off. With QIS not conducting, Q16 ts biased the’ voltage on the AGC Tine to becose less positive, off, which forvard biases QI7._ O17 conduction applies Feducing the gain of Q6 (AM IF Amp), 209 (RF Amp), and . ground to pin 7 of IC2 thru RIS-and RIG. With pin 7 of 210 (Hiner). Tc2 grounded, 1C2 4s turned off. RV7'(AM SQUELCH RANSC) allows the squeleh etrcuit to be preset to a predeter- EE A Wigs Anighe 68 pos tion snd _onder-ms’ stone} ined stgnai Of 1000W at the antenna ‘conector (31) with eRe eTon, (639 charges through R54 with e slight forward — yRa"(sQuLCH) set at eaximum for AM operation, RVB (SSB i dasrecress OUt; (ONG Je As, tee, detected audio teve) SSQUELCH RANGE)’ altows the squelch cfrcuft to be preset to Ancreases, 39 15 allowed to charge according to the a predetersinec signa) of 1000u¥ at the antenna connector ‘average audio level, increasing the fonard bieson O16, — ,P18ds sue arin for ration, Since DUA 5 tn series with the audto sional paths any (01) wt» WED (SOUELCH) set at sarimas for $58 operatic egative spikes that’ are high compared to the average ; | audio Vevel will overcone the forward bias on DIS and AUOIG. Audto from C40 (In AH): and R49 (Tn sss) sree ed open the signal path momentarily to mute spikes such ax % VRZ (VOLUME). The audio fron VR2 (VOLUME) wiper 1 those generated by an auto tgnition systen. With 5-3 coupled tothe base of Q14 (BUFFER) thru C77. The output ‘sat to NB or OFF, RED 1s no longer in series with C39, fron the enftter of Q14 fs coupled to!the base of 13. (AF Gecreasing the Ri tine constant, causing Did to remaia dao)» thru C78, RSE, and CS3.- The amplified output 1s tn conduction. soupled to. pin'6 of IC) (AF Aap): ‘thry R72, C57,. and R74. “The outrut of 1C2 15 capactttvely ‘cowled'to TS thru C66. SIGUL HETER (AN)~ Diode D9 rectifies the positive ‘Audie froa TS secondary 1s, coupled thru C70 and S-5d to ‘envelope of the rodulated IF signal and feeds the re= J3 4n CB position, With no. external speaker connected, ‘sulting DC current through RVS to the SIGNAL-POWER Ret the audio path fs thru J3 and'RO2 to speaker (SP). From Gi), AVS (AN SIGUL HETER ADIUST) 45 adjusted ter enspe pester (SP) to pin 3 of 98 (HC Plug) and thru the swith a coed microphone to ground (pin 2 of 35). in AM ang SSB oye col stomal at the antenna comector — Tictiver G19 (Oe SuTTEI) te blazed on'to ground’ C59, Vowing ICS to have eaxtmum gain.” In C6/PA posttion KIXER ($S8)- The amplified signal fron the collector of audio 13 coupled to J2 (PA). When C511 and (512 are fs developed across 1205, which 1s peaked tuned to Sounded by TONE switch $4, high frequency audio tones Zits, The signa ts coupled to the base of G210 thru are shorted to ground, €235 and 1204, which 1s peated tuned to Z7Hiz. Signal at the base of G20 48 wind with focal ovetitator PA+ In PA, audto ts coupled fron MIC thru pin 1 of JS to ‘Signal (37-660Hir ~ 38,1004 for USS and 37-6572 ~ ‘Vida (MIC GAIN), Audio from HIC 15 controlled by ¥Rta ‘38.097iGir for 158) from the frequency synthesizer. The end fed to pin & of IC2. In CB/PA or PA position, the IF"signal ts developed across 120? which 1s tuned f output from pin 10 of IC2 ts coupled to 02 (PA) thru C66,, éitterence frequency. Huned for the TEICO, and S-54 and J2 to ground. 2 % 4/78 GENERAL GS ELECTRIC MODEL 3-58258 NOISE BLAMEER. Notse pulses fron the secondary of 1207, SCross L709 thry CZ49._ 1209 tx tuned for 27m. 9208 ‘are coupled thru C272 to base of 211 (NOISE BLANKER). "180 operates class °C* for waximun effictency,/and the Aaplified noise pulses from the collector of Q211 are Cees TUT outiut 18 developed across 1207 and’L208. coupled thru C273, C276, and voltage doubler circuit z are series tuned to 27Hiz. A pi-network, Towepass filter, 13 formed by C253, 1213 and C254 1 D216, D217, C275 and C274 to the base of G21Z. The or ge ucts Sacre ane lla aq Ic acing to Eola ene ch ee fed to the base of 0273 thru F-C network C278 and R259. for Lepel operation. R2G8 1s used as « static discharge The signa} at the base of 0213 varies the resistance of | leeder. L214, tuned 24 18 used for antenna Q213 to ground, The noise 1s shorted to ground thru matching, Bh gt i retard rs gy a ef trent cee ot re > &212, L213, and C287 to (RF Detector) POWER DISTRIBUTION + 0227, The RF detected by 0227 ts filtered by C286 and - + C265 and fed to Meter (HM) thru RVZ03 (POWER)-RY202 tn ‘This unit 1s designed for operation from a standard 12 Some models. RV203 1s adjusted so the internal POWER YOC automotive power suoply. Dfode D2A provides polarity Meter (H) agrees with an external RF wattneter. en that will case the tose to ow ae fipply lant are'reversedy owcpss ficering fr prov YOQUATIN (W)- Aud tro tne mtrophoe tk coupled fi A vate Erb, Roby a Tided by Lye UB Chand Gh to attenate notes from the aco ian vine seelifiea eptoee or eed se ‘a coupled Le Pa A ee pin 6 of 1C2, In i, Unregulated B+, switched only by On/Off switch 51 (part ‘trensaity G19. (0C s biased by O18 (OC SWITCH), ‘of volume control), 1s supplied to PLI (Meter Lamp), IC2 grounding C55, perattting maxfeum gain of 102. | 1C2 {AF dep), and TS (Audio Transformer)z With auiten Sse, @Tives the output transformer TS thru C66 to the level . ulated B+ 1s al _orTequired for transnit modulation. The B+ for 0208 (RF Udnanath Selech) thee Se2h to VRS AM Pseert® Satege POWER) ‘and Q207 (RF DRIVER) 4s supplied from Vai (AX Ulated Be fron SS-c 1s also fed through 3-20 (tn upper POWER) thru. T5 secondary and 023.:°023 limits the maximum and lower sideband positions) to PL2 (TX ‘sao 0207 (RF. sodulation and provides: shaping for tnproved modulation Driver), Q208 (RF Driver), 0203 (RF Power), G2i6 (AVR), > ‘Vineartty. Thus, the B+ increases and decreases at an tnd O29 (hixer). Unregulated Br alse'goe! thrown h73 Austo rate varying the amplitude of the radiated carrier. to provide voltage for Q13 (AF Amp) and thr R231 20 920s NOTE: The modulated B+ Vine’ can reach peak voltages up itr’ Preasp). to tice the power supply voltage. An independent, well regulated 8.51 OC 1s provided by AWAF ALC Audie from the cathode of 23 1s coupled to enitter follower cfrcuit of G216 (AVR) in conjunction ‘the Base of Q20 (AF ALC) thru RVG (AF ALC), C71, 022 and with a S-volt reference diode 0215. This regulation RBS. Audio Supplied to the base of Q20 fs rectiffed by voltage 45 applied to Q210 (Mixer), Q7 (SSB IF Amo), Q6 . O22. This rectified voltages varies the resistance to (ATF sep), O5 (An IF top), 1C201'(¥CO Mixer), 0203 (Osc ground for the audio signal supplied to IC2, thus re9- J). O4 (Butter), Switch $2 (LSB, AN, USB), Switch 3 ulating modulation. RVI 13 adjusted for 1001 endulation (WE/AML}, IC) (Balanced Hod.) and RY7 (AN’SQUELCH RANGE). with a 1000Hz, 20s signal at pin 1 of 05, with ¥Rée (NIC The regulated B.5Y DC 15 fed through R216 and drops to GAIN) at maxi, $,26V DC, regulated by D206 (5.4 volt Zener). This 5.25 DE 45 the supply source for 1€201 (VCO Mixer, 0202 (Osc _TX(MOD)INDICATOR(AN)- The modulated B+ Line from DZ3. goes 2), 1€203 (PLL 02), the YCO-Osc Block. and Switch Swi ~~ “to Switch ISB}, to PL2 (AW1), and thru PL2 to (Channel Selector). Voltage 1s supplied fron Q216's — . G205 (OC SWITO!). 9205 12 biased on tn’ eaitter to $2. In the AH position, the voltage {s then avcltched through’S2'to the collector of O43 (0c SWITCH) and to the collector of 0217 (DC SWITCH). (217 1s AXT WARNING INDICATOR (431) Ith a standing wave voltage forward biased (1m receive) suppling voltage to 06 (AM IF_ . ratio of 10 to 1 or greater, significant voitages:are Amp) and Q3'(Osc 3). The voltage also goes thru 0222 to". rectified by D21S and B214 to forward bias, Gzid and QV6 (SQUELCH), Qz11°{WOISE BLANKER), In transat, O717 -.- Teverse Dias G21. The voltage from the eolieetor of ransit. The ‘modulated 8+ Vine varies the intensity of PL2 (ANI). 1s Diased off-and Q218 (DC SWITCH) 12 forward biased thru | 9214 causes Q221 to conduct, lighting PL3 (AN! RI R265, Voltage from 218 1s supplied to GZ14 (AMI), G215 and RVZOS are ausisted with Unie in prenemdte oe Poe (ait) and O221 (Aut). The voltage supplied by Q218 ts ghts with a 150 ohm non-inducttwe resiitor’conected Me pply woltave for Sues Ana AS aes to ey Eee oes Ua int Ire (iF DRIVER). and 2 in). : TRANSHITTER $88- Auto fron ts coup In. USB or LSB positions the voltage thru S2 supplies BGS UHPICURGE (MIC ALND G Coes Aes eee eae eet voltage to O18! and the collector of Q219 (Oc SWITCH). is. The amplified output Of G13 te toemees anes ae Q219 is forward biased in recetve. The voltage from the C57, and R74 to pin 6 of IC2, In/SSB transmit Q19 (DC enitter of Qz12 supplies voltace fo 91 (SSD AGC) and G1. Sittci\tx based att by GIG (OE Seiten) placing R77 in (SSB'DET), thru 0223 to Oi (OC SWITCH), OB 09 {SSB IF Sertes with C59 to ground, causing IC2 to have lower gein hap), O14" (SUFFER) and Q16 (SQUELCH).. ‘In transmit, Q2i9- than"Gn'AN poration Geo wit ae insects ora 4s biased off and Q220 4s Mased on thru 8267. Voltage _Ac'anp for S$ operation. The reper ey Tee tone te supplied from Q220 goes to Q18 (DC SWITGH) and 0225, coupled thru RE, C82. RG (SSE MIC GAIN), Rs, "and Cis < ‘to pin T of IC¥ (Balance Hod). ICT bas two inputs, one Voltage supplied from S2, in LSB position, provides blat” {2 the auifo at pin te the cher te che corpse Ba ree for Gz04 (DC SWITOY) and'G2 (DC SKITCH). 3) sora Ot (QuFrER) The freeucney of 03 tery 66 ee a fuffer) 4s 10,695iViz tn USB and 10.682042 in LSB, With TRANSMITTER CIRCUITS Fs both inputs present tn ICI, the output will be the sum or “ ‘4sfference input. “With pin'1 of 25 grounded, RYI and BE PREP (WN) Unsodulated RF at the selected CB center RYZ are adjusted for MINIM RF output at di. In USB the frequency ts fed from pin 9 of 1202 (MIKER/RF ALC) thru’ difference in frequency developed by IC] wili be passed 6235, 7205, and C24) to the base of Q206, The unmod- by the steep side skirts of the anpll tude-verses-fre~ ulated RF from pin'9 of 1C202 1s developed across TZO. quency response curve of the filter MXF-1, In LSB the T2OA and T2OS are peak tuned to 27Hz. The amplified RF sun Frequency developed by ICl will be paised by HFT. 1 developed across paralled tank circutt 1209 and C244, . The output of 1C1 (Pin 7) 1s complete thru C19, R21, D3, tuned to 271012. HEI-1, and RUA to base of Q7. The output of Q7 ts -de~ veloped across 13. The secondary of 13 feeds thru C87 RE DRIVER (AM)- Q27 base 1s driven by RF sional coupled . and C229 to pin & of 1202 (HISERV/RF ALC). Pin 4 of Tram the seeohiany of 1209 thru CNG” G20? toe groumied C505" ‘approximately 10.69351Hz, 1s mixed with the emitter stage for high power gain, and operates at class frequency supplied to pin lof 1C202. ‘the frequency at Sct (E-B junction reversed biased) for mxfaun efft- pin 1 (e202) varfes with each channe? (37.660°t0 clency, The output 1s developed across RFC L205 which 38, 100Hz for USE and 37.657 to 38.0977 in LSB). The presents a high expedance to RF without blocking the ‘output of the mixer, pin 6, 13 fed thru (230 to pin 7 of Audio rodulation, : 7 SF ALC, The output from pin 9 of RF ALC 15 developed across T204 ard coupled thru C235, 1205, and C43 to the RF POWER (AM)~ MPH power transistor Q209 1s driven by a base of Q20C, T204 and 1205 are tuned for 27H. pional trom ‘collector of 0207 thru C248, developed me 4/78 2 MODEL 3-5825B RE PREAMP Modulated RF at the selected CB frequency 4s Ted Tron pin 9 of 1202 (HIXER/RF ALC) thru C235, 1205, and C241 to the base of 0206 (RF PREAMP). Modulated RF from pin 9 of 1C3 4s developed across 1204. 204 and 205 are peak tuned to 27HHr, The amplified RF is developed across paralvel tank ctrcutt 1209 end C244 which are tuned to 27H1z, (206 1s disabled by Q201 (thru R228) tn SSB Recetve. . RE DRIVER (358)- The Q207-base is driven by RF signal ‘coupled from the secondary of 1209 thru C246. Q207 1s ‘grounded emitter stage for high power gain. The output 4s developed across RFC L205 which presents a high Ampedance to RF. RF POWER (SSB)- HPN power transistor Q208 1s értven by & ‘S¥gnaT from the collector of 207 thru C248 developed ‘across L209, thru C53. L209 1stuned for 27H4r. 208 operates class °A" for maximum Vinearity and the RF ‘output 1s developed across 1207 and 1208. The bias for 208 ts developed thru 8237, R238, and L205. C252 and L212 are series tuned to 27#0iz, (253, (213 and C254 form a Towspiss filter, Pi-network, tuned for impedance matching to a 50 ofa antenna, required for legal opera= ‘tion, R268 ts used as a static discharge bleeder, L214, ‘tuned to 27MHz, 15 used for antennd matching. RF ALC (SS8)~ The RF output from Q208 4s fed thru C252, Eee aBi ane D205 to RVEON CALE). “DgON and O29 rectifies the RF signal. The RF voltage ts Fectified and ‘filtered then applied for reference at RV201 wiper. When the voltage exceeds reference voltage, a voltave 15 fed tw BF ALC to decrease the gain of 1C202, SSB_AF ALC- Audio from pin 10 of ICZ (used as HIC Preanp in 'S coupled thru C68, R2, 021 and RBG to the base of Q20, Audio supplied to the base of 020 1s rectified 022, ‘This voltage varies the resistance to ground for ‘the avito signal supplied to 1C2, 2 DIGITAL FREQUENCY SYNTHESIZER (includes Phase Lock Loop (PLL) Circuits) GENERAL The synthesizer used tn the single sideband Scelver generates four crystal controlled frequency outputs. One, at channel center frequency, 13 used for Griving the RF transattter ctrcutts, The second 4s used a5 the first local osefllator signal for Al or S38 fecefver operation. The third 15 used tn AN mode as ‘the Jocat osctilator signal for the AX second atxer. The remining outout 15 used as 2 transmit offset frequency Jn AM or SSB and as a beat frequency oscillator (BF0) for sideband reception. For precise accuracy and frequency stability, this unit incorporates the Phase Locked Loop (PL) systes, 5 7 Bastcatly, phase locked Toop fs an electraiite servo-loop consisting of an oscillator whose output frequency 15 controlled by a OC voltage, s phase comparator that Generates a DC voltage directly proportfonal to the Frequency difference at fts inputs, and # low-pass filter ‘to "smooth out” the DC correction voltave. The phase . comparatar cantinuously compares the output of the Voltage controled oscillator (VCO) to a reference frequency and uses the DC correction voltage to shift the VOD frequency until the VCO 4s locked exactly tn phase with the frewency reference. To generate the crystal controlled frequencies required for SSB transceiver operation, while keeping the com plexity of the channel select systen at a reasonable Jered, both linear (heterodyning) and digttal (countdown) tachniques-are eaployed. WOO- The YOO section of 1€201,"pin 1 and 2, operates Gaal Cin AX and USB) 9.47182 (in 158) below channe? Canter frequency, Within the VCO ose{Tlatar block, the capacitance of the varicap diode 4s contro?led by the DC correction voltage from pin § of PLL cfreuit 1C203, The and (202, shead of the YOO block, ‘“Eple**trom the OC correction voltace, The renoves any inductance in the YCO block (VCO) 4s adjust for 3.6 woits, 401 volt, at TP in USB charinel 1, Q202 (Ose 2) 1s used as-a reference oscillator et a frequency of 10.240Miz, ” adjusted by C1201, Capacitors C206 and C208 are terpera~ ture compensated to ensure reference frequency stability. Qz02 output 1s coupled to pin 3 of 1€203 (reference Anput) thru C209, 0203 (Osc 1) 18 the offset oscillator GENERAL 3 ELECTRIC which {5 crystal controlled by-1202. The output of 0203 4s tuned tothe second overtone of 1202 by T201. In ANE USB, C1Z02 ts adjusted for 20.105HHz, tn USB, CTZ02, grounded thru Q204 (OC Switch), ts adjusted for 20.1035"H2 at TP3, The output of the collector of 203. 1s coupled ‘to one input of the mixer section of JC201 (V¥CD-Mixer) pin 4, The other input of the mixer 4s supplied in- teenaity by the VOO. The mixer output, pin 6 of ICZ01, fncludes the sim, ané difference frequencies 25 well al the fundamentals, The difference from the mixer pin 6 of ICZO1 ts selected by 1207 and C224 and coupled to pin 7 of 1C20) thas C222. Pin 7 of IC201 {s the input to Sitferential arplifter section of 1C201. Pin 9 of 1201 4s the output and 1s coupled to pin 2 of 1203 thru C223. ‘This frequency ranges from 2.1}Miz to 2.55¢iz, depending on channel selected, The sum fro the mixer, pin 6 of TC2O1y 1s developed acrosm parallel tunes circuits 1202, coupled by (225, and 1203, The output of the secondary Of 1203 te coupled to pin I of 1C202 thru C228, This frequency 37,6600r to 36,100H2 in AN & USB, and 37.657H12 ‘to. 38,0972 tn LSB, 1s coupled to Q210 (Mixer) thru E227,” 1203, a large scale Antegration PLL ntcroctrcutt, is the heart of the digital synthesizer. There are two inputs to 1C203, one {3 the reference input at pin 3 of 1C203, the other, @ sample input at pin 2, 1s the dif ference produced in 1€201. Both reference and sample Anputs are counted down to 10kHz. The reference input is divided by dtgital frequency divider composed of chains Of flip-flops Interconnected to give & square wave, Sividedcdown version of the tnput frequency. The reference frequency 43 divided by 1024 to give 1Ouiz.” The sansle input is divided by a programmable divider down to }0kiz. ‘The projramable divider divices by a non-fixed divider Gestgnated “a which 1s prograrmed by selector switch SWI and provided to 1C203 at pins 10 thru 15 (See chart on page B. The two lObHz signals are then-Internally Supplied to phase detector and compared. The phase Getector generates a correction DC voltage directly Felated to the difference in phase. This voltage, pin 5 ‘Of 1203, 43 suppled to the VOD to EMIfE the ¥CO fre- ‘Quency 30 the VOD and the reference input have no phase - difference and 4© ines ILOCK- Bias current for RF predriver Q206 4s suppl ted ‘Ghewogh R228 by switching transistor Q201. D201, tn the rare Dtreutt of Q201, ts noraally reverse biased, with verontastely SV DC at the cathode. However, when there re cignificant phase cifference in the PLL ctrcutt. Jiatcating an outeofelock condition, the unlock detector {n1€203 grounds the cathode of D201, renoving bias fron AQ20IC Thane with Q20) and Q206 turned off, there can de ce ott-trequency transetsston during the lock-in period, ‘T_OFFSE’ BFO- Q3 {Osc 3) 4s used to produce both & Fa ore eer eaueney end a €F0 for S86, crystel 1 Fee eee err to adjusted for 10,6900 38 ‘AM (Transnit) & USB operation. In LSB, Q2 (DC Switch) ts turned on, grounding C2 and C12, allowing Q3 to operate at T0,692MHz. Q3 4s biased off fn AM receive position. . In AM transait the signa) from the emitter of Q3 ts Tae era rae etary of Td thru Coy 87, AZ3, MFT, cae te SecOnUaTY ef te the prisary of Tae tn $88 Rake mealfed 29 0) aes {fred to the emer of G10 for SperatAon the est hae Os detectarss ra C6n 04, and CBD, ‘The third output’ from 03 is fed to the Balance fod, pin 3 Tae ated pee ese od and EWN, C202, the Transat Hee ee ees aden only tn trenamtt._ One tnput to the mixer ts from IC201 (VCO-Hixer) ‘to pin 1 of 1C202. ‘The other input to 1C202, pin 4, comes: from the secondary wee aiettaae of the etaers pio € oF 1C202, 1 coupled to pin 7 of 1202 (RF-ALC ‘Amp) whose output 15 fed to fthe RF Preamp. CLARIFIER- The clarifier gives 4 “fine tune” adjustment Futueeh nodulated IF sional supplied to the SSB Detector Q10 and the BFD signal supplied by Q3 (Ose 3). To give the unit this adjustuent the frequency of the TF sonal Ys varied slightly, To vary the frequency of the IF the Plt frequency suppited to the (First Hizer) 210 ts Varteds To vary the PLL frequency the tuned circuit of 203 (ase 1) 4s varied, In Receives voltage 15. supplied ‘to R221 which biases D204 on, allowing YRS (CLARIFIER) to Very the voltage to varicap 6203 and thus the frequency OF e203, The Frequency can be varied tn both AM & SSB Sective However, tn transmit AM or SSB, 0205 1 turned One suppling «fixed voltage and 0204 ts tuned off Giiabving clarifier VR5, in accordance with FCC rules about varying AT frequenctes externally. 4/78 MODEL 3-5825B . GENERAL QB ELECTRIC ALIGNMENT INSTRUCTIONS Allow. 15-pinute wars-up period. Adjustaents made with 15.8-volt Dc input, Connect microphone, 71,72, 1207 , 7208, eee 1209,1212,1214,T209,, T3,74,T201 thru T206,V00.. 9420 ¢T1,Cr2,CT201 ,CT202,CT203.. 18276000 Suggested Alignnent, Tools: GC ELECTRONICS: 5009, 8728A,8728 '9091,8728A, 8726 Connect low sides of test equipment to ground unless specified othervise. Connect &0-ohn dumy load or antenna before keying transmitter. CAUTION: Use isolation transformer or observe polerity when connecting test equipment. SYNTHESIZER ALIGNMENT ‘TEST EQUIPMENT ‘TRANSCEIVER ADJUST REMARKS Input of frequency counter to cr201 Adjust for 10.240Miz. ‘TPZ4(Q202 Collector), : : 6 2 Input of oscilloscope to.1P3 T201 Adjust for maximum RF. (IC 201, Pin 4). £ ° Input of frequency counter to cro Adjust for 20.10SHiz. - ‘TPS (1C201, Pin 4). : : ° €r202 Adjust for 20,103SHHz. Clarifier 0 Input of frequency counter to G, 19, cn Adjust for 10.69SHiz. ‘TPS: (G4, Emitter). USB : Clarifier 0 ¥ G, 19, oR Adjust for 10.6924,” 1s8 Clarifier a Input of DC meter to TPl. chet,” vo! Adjust for 3.6 volts. : USB Clarifier 0 Anput of oscilloscope to TP13 , 40, 7202 Adjust for maxima RF, (icz02, Pin 2). : USB : Clarifier 0 a1, ros Adjust for maximus RF. 1B Clarifier 0 Input of frequency counter to a. 1, Gheck for 37.660Hi2, ‘TP13 (1202, Pin 1). USB or AM, | Gheck a11 channels. Clarifier 0 (See Truth Chart for 5 correct frequencies). Input of frequency counter to> | Ch.-2, Gheck for 37.6572, PLS (1C202, Pin 1). 1sB heck all channels, Clarifier 0 {See Truth Chart for correct frequencies). — TRANSMITTER ALIGNMENT - transmitter. See channel frequencies chart. Connect an RF wattmeter and S0-chm, 25-vatt dumy load to antenna connector. MOTE! Be sure to check transait frequency and pover on all active channels after alignnent of 8258 + GENERAL @@ ELECTRIC $sB TEST EQUIPMENT TRANSCEIVER ADJUST REMARKS Inject @ 2400lIz, 2.5nV signal Gh. 40, 1204 ‘Adjust for maximus, at MIC input. USB MIC-AWR Maximum Inject a 2400HZ, 2.SmV signal oH. 2, ‘T20s Adjust for maximum. at HIC input. : : Inject « 2400Hz, 2.5nV signal : Gh. 195 ‘73,7209, Adjust for maxinun, at MIC input. USB 1209,1212, i MIC-ANR Maximum Lae é ~ TRANSMITTER ADJUSTMENTS: Connect an RF wattueter and SO-oha, 2S-watt dwmy load to antenna connector. NOTE: Be sure to check transmit frequency and power on all active channels after adjustrent of transmittor. See channel’ frequencies chart. i i TEST EQUIPMENT No signal input, TRANSCEIVER , 19, BALANCE we : ‘Adjust for MINIMUM RF. Inject « 2400Hs, 20nV signal Gh. 19, RVS,RVZ0T | ALC at MIC input. USB ‘Set RVS to nidrange. + + “| MIC-PWR Maximo Adjust (RV201 for 12 watts maximum. If necessary: ¢ adjust RVS to obtain es 12 watts. Inject e 1000Hz, 20aV signal at a. 19, 9 AF ALC MIC input. my ‘Adjust RV9 for 100% Input of oscilloscope on MIC-PwR Maximum rodulation, maxizun, nodulation meter to antenna jack. Connect an RF wattneter and SO G. 19, va. ‘AM POWER. oha2S watt dummy load to antenna | AM Adjust VRI for 4 watts. connector. Connect an RF wattmeter and 50 ohn/25 watt dumy load to antenna ‘connector. ch. 19," Rv203 POWER METER am . ‘Adjust RV203 so that : POWER weter agrees with She RF wattmeter. Connect a 150 oha/S watt non- _ | Ch. 19, Rv202,RV20S | ‘ANT inductive resistor to antenna a Set RV202 to midrange. connector. ‘Adjust RV20S so that ANT Andicator lights. If necessary adjust RV205 so that AVE Lights. RECEIVER ALIGNMENT Connect an AC VIVM or AF wattneter across speaker voice coil. Adjust volume control to obtain a suitable indication. . [Set generator autput low enought to prevent AGC Limiting. _ | = TEST. EQUIPMENT TRANSCEIVER ADJUST REMARKS: Gutput of signal generator thru |Ch. 19, AM 1,71 Adjust for saximum ourput. -O1uF to’TP1L (Base of QS). > | RF Gain Maximum é 4SSkitz,1000Hz @ 30% modulation, | Clarifier 0 Squelch MINTHt NB* ANL OFF Output of signal a. 19, aM 208,7207, | Adjust for aaximm output.

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