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Summary of Contents for GR-61

Page 1: ...a PR CE 1 OO Lt vvL q67 t r 1 ijt r if A SSE 4E I Y IAA NT IA I H TA TH IT FM PORTABLE RADIO MODEL GR 6I tii ...

Page 2: ...OMETER coNrRoL c ELECTROLYTIC CAPACITOR ll lt COLLECTOR TRANSISTOR EMITT ER COLLECTOR EM ITTER m f lpaxsroRuER f o RECTIFIER DloDE c emi l3PER PoWDERED rnol I V1 J cone ennow I li t Lrh i H nM BATTERY I l NEON EULB I Z rnr sroRMER t_ t PHONO r o Y ttx Jl ffi lf l_ PowER TRANS lL FoRMER PHONE JACK O I NDUCTOR colL RECEPTACLE q sPsT swlrcH TOGGLE l r DPDT nlF 39 fI fl S PEAKER d swrTcH A4 n o 7 U o ...

Page 3: ...Circuit Board AssemblY Right End Plate Parts Mounting Left End Plate Parts Mounting Circuit Board Mounting Wiring Circuit Board To End Plates Final Wiring Final Assembly Initial Test And Adjustment Cabinet AssemblY Operation In Case Of DifficultY Troubleshooting Chart Introduction To Transistors Glossary Of Radio Terms Circuit Board X RaY View fold out from Page Cqyrlghto t962 12 3O 66 2 3 3 D 30 ...

Page 4: ...ligation to 88 to 108 megacycles 10 7 megacycles 3 uv for 20 db quieting average 5 uv for 20 db quieting maximum Measurements takenin aligned condition Volume Tone and AFC 3 2N174 4 2Nt274 1 2N24e5l 1 2N26711 in FM tuning unit 1 2N26541 Collapsible whip with provisions for external 300 Q antenna 4r x 6t oval permanent magnet type Six l l 2 volt size C cells 300 500 hours Earphone or hi fi output 9...

Page 5: ...city each section will be discussed separately Refer occasionally to the Schematic Diagram while reading tris descrip tion To help in reading the Schematic the letter number designations for t e circuit parts are number coded as follows 1 to gg for the FM tuning unit and 100 to 200 forthecircuit board and chassis For example resistor R3 ig in the FM tuing unit and resistor R 103 is onthe cir cuit ...

Page 6: ...plied by six 1 1 2 volts size C flashlight batteries IF LIMITER SECTION The 10 megacycle signal from the FM tuning unit is appliedto Q4 the first IF amplifier From Q4 the IF signal passes through transformer T3 which passes only the difference frequency of 10 megacycles to Q5 the second IF amplifier After additional amplification in Q5 the signal is applied through T4 the second IF transformer to ...

Page 7: ...llow 1 megohm brown black green PART PARTS No Per Kit Controls Switch 5 10138 1 6 1e 81 60 18 1 Choke Transf ormers Diode DESCRIPTION 100 KO linear control 10 KQ control with SPST switch SPST switch Resistors 1 1 T20 t 4L L 2 t 45 1 8 1 9 1 10 1 13 t r4 1 16 1 19 L 20 1 109 L 21 1 69 t 22 1 60 r 26 1 35 Capacitors 2 2 2t 46 2t 94 3 25 54 4 25 11 5 25 116 25 tl 25 11 1 8 45 35 e sr sz 51 98 10 52 5...

Page 8: ...1 250 4e 2 250 156 3 250 138 4 250 22s 5 250 56 6 250 8e 250 106 8 250 10 343 344 50 344 1 6 344 t5 346 1 ilrlr 2 fo 3 frfril ro flinm rr rz rQ2 F 16 e7l I 5 61 71 8 fl ii i l p i rr gF t t I 2 8 3 d 2 n 4 4 2 1 1 2 4 10 4 2 wire wire wire s 252 r 10 252 15 11 252 3 L2 252 22 3 48 nut 4 40 nut 6 32 nut 6 32 speednut ls 16 l z1 g r a1 l e 20 21 ezl r3 255 11 24 25e rt 25 25e 12 26 455 31 2 258 30 M...

Page 9: ...1 3 4 331 6 595 593 Right end plate Left end plate Batterv contactor 1 1 1 I I 1 1 I 1 1 1 7 I 1 I 1 2 1 1 1 1 1 2 3 1 P E C packaged electronic circuit Circuit board Cabinet front Leather case FM tuning unit Nameplate Spealer 2 screw terminal strip Transistor socket Earphone jack Small tuning larob Large tunlng knob Volume knob Tapered knob Alignment tool Allen wrench Collapsible antenna Battery ...

Page 10: ...AKING CAR OF THE SHIEI INSULATION PEEL OFF TI THIN WIRES Defoi Detoil lA dj BE INSERTED FROM THE TOP LETTERED SIDE OF THE CIRCUIT BOARD THIS IS THE SIDE OPPOSITE THE METALIC FOIL 1 ir REMOVE THE SMALL IYIRES AMOUNTS OF LEAD ANO TH SOLDER v L2 Ator w ire s 1 othe heat may resu leadr conn KEYWAY ...

Page 11: ...mount the I circuit boal lettered si socket Posi of the circu align ProPe all four Pir lrcard Be r unused hole Referring tapped spa the circuit These spac keep it le rePositione Proceed to Pic steps surroundi Refer to Picto Remove th lettered sit them on th using tlte s PICTORIAL 3 PICTORIAI I PROCEED TO PICTORIAL 2 ...

Page 12: ...ill be removed and repositioned later Froceed to Pictorials 1 and 2 and perform the steps surrounding the illustrations Refer to Pictorial 3 for the following steps Remove the four tapped spacers from the lettered side of the circuit board Then mount them on the foil side of the circuit board using tlle game screws PICTORIAL 3 NOTE When using hookup wire in the following steps cut the required len...

Page 13: ... excess leads at the soldered joints on the foil side of the circuit board NOTE When mounting transformers in the fol lowing steps carefully align the pins of each transformer with the holes of the circuit board The spacing of the transformer pins and the holes of the circuit board are such that when alisned properly ttrey will mount easily withoutforJing 15 16 1 T7 Install the outputtransformer b...

Page 14: ...h sl s la M al p M i Set U LEFT Refer M oo __l tl r T 8ru r3z Ao V fi AFC swtTcH c f l u I lAFc r tl tl r I te I r ea De nfc AGC NIT 6 FM ING U t a Qz B t l c SOLDE R LUG l N E 2Nt747 Q4 Yd tF N iiii lT l k1 ...

Page 15: ...Ao t e il AFC swlTcH a nu I lAFc L_l r a __ r o a oC nf0 AGC TUN NIT 6 FM ING U l a z B t ic SOLDE R LUG lt c l I ve I C RF 1__r N E 2Nt747 o4 0r d rF N r jiil i rj f 4E k1 M br tt s1 st Ia M AJ p M 1 Set tl LEFT Refer M ...

Page 16: ... Page 10 6 32 SPEEDN FLAT SIDE 6 32 NUT LOCKWASH ER T ER MIN A RIGHT END PLA Refer to Detail Mount two 6 plate Be surr is positioned NE o TO 3 lNr274 A L EQ5 n TONE lc r Vr f I l I _ rfrffi BATT_ f i 7 O O O a1 OLJ 2N1747 A C BGF Y fJ Deloil 1F PICTORIAT ...

Page 17: ...te Be sure ttre flat side ofeachspeednut is positioned as shown Detdil 4A Mount the antenna bracket to the end plate Use 6 32 x 1 4 binder head screws 6 lock_ washers and 6 32 nuts Mount the 2 screw terminal strip to the antenna bracket Position it as shown Use 6 32 x 1 4 binder head screws 6 lock_ washers and 6 32 nuts Mc bri thi slr sol lar Mc an pol Mc 6 Set thr LEFT E Refer Mo RIGHT END PLATE ...

Page 18: ...ial 4 Mount the preassembled FMtuningunitwith 6 lockwashers and 6 82 x B 16n screws Set the right end plate aside temporarily LEFT END PLATE PARTS MOUNTING Refer to Detail 48 for the following parts Mount two 6 32 speednuts on the left end plate Be sure the flat side ofeachspeednut is positioned as shown Mount the Volume control 19 g1 with a large control lockwasher and large control nut Position ...

Page 19: ...sthatholdthe circuit board to the top and bottom brackets WIRING CIRGUIT BOARD TO END PLATES Refer to Pictorial 4 fotd_out trom nage tO for the following steps Conhect the free endg of the wires comins from the circuit board to end plate terminils as directed in the folloWlng steps Connect a 05 pfd digc ceramic capacitor from lug 4 S 2 to lug 1 S 2 of the Volume control FROM CIRCUIT BOARD POINT ea...

Page 20: ...t as in the next step it will count as two wires inthe solder in_ i15t1ctio1q S 2 one entering and one leaving me connection Connect one end of a Z g 4 wire to ANT_I ot 9 r i tuning unit S_1 Strip 2 o in_ sulation from the other end ot tiis wireand pass the wire through the solder luE at ihe antenna bushing s_2 to AltT_l of the Z_ screw terminal strip S_1 Connect a 3 L 4 wire from ANT 2 of the 2 s...

Page 21: ...llation and conect positioning Referring to Detail 4E cut the leads of the four 2N12 4 transistors to 3 16 and install tfiem in the proper sockets accord ing to the Transistor Location Chart Referring to Detail 4F cut the leads of the three 2Ni 4 transistors to 3 1 6 and install them in sockets Q4 Q5 and Q6 FINAL WIRING Refer to Pictorial 5 for the following steps Cut both leads of the 10 pfd tubu...

Page 22: ...he following steps Position the red wire coming from tlre Volume control through slot A to the plus spade lug S 1 Clip off the excess wire close to the spade lug Position the black v rire coming from the circuit board through slot B to the minus spade lug S 1 Clip off the excesswire close to the spade lug Referring to Detail 6C mount the battery contaetor and spring on the remaining bat tery holde...

Page 23: ...attery con tactor onto either end of the batteryholder until it snaps into place Position the plus end as shown Install battery end C on the battery hold er position the plus end as shown Place the battery holder in the battery compartment as it is shown in Pictorial 7A Be careful not to damage theearphonejack This completes the wiring of your Portable FM Radio Check all wiring for anypossible err...

Page 24: ...t the knob on the switch lever and tighten the setscrew PICTORIAL 78 Instalt the collapsible antenna and extend it t9 its full length To insure proper fit in the case move lhe antenna foiward bend ing the antenna bracket until the antenna lines up with the corner of the end ptate as shown The antenna should remain par_ allel to the side of the end plate NOTE Ttre blue and white identtfication labe...

Page 25: ... ADJUSTMENT Rotate the Volume control cloclrwlse util it clicks to turn on the Radio A hisstng noiee should be heard from the speaker with furtler increase in the Volume setting U no noige ls heard from the speaker refer to the In Cage Of Difficutty section of the manual Q DISCONNECT 4 vscE 7 Flsure t qQ o Bu f o 1 i T4 Jrb trLi o1f I t il E Ou ro i ee l o C O rr arrd 5 r o ll o rJf lr ol l l l I ...

Page 26: ...sarv to carefully retune the station and repeat ihis adjustment R 9rr9 the alignment tool carefully so as to not disturb the setting of the slug COMPLETE ALIGNMENT PROCEDURE USING A swEEP GENERATOR MARKER GENERATOR AND oscllloscopE Tuning Control off station position Make sure the sweep generator output signal Volume Control full counterclockwise switch i i gh i o p rr nitimitinginthelF stage 3 AF...

Page 27: ...he cabinet front with four 6 32 x 3 8 self tapping screws Loosen the five screws that hold the end plate to the top and bottom circuit board brackets and push the circuit board down so the speaker is tight against the cabinet front Tighten the five screws in the end plates Refer to Pictorial 8 for the following steps Remove the two screws that holdthecircuit board to the top threaded spacers Caref...

Page 28: ...binet front This completes assembiy of your portable FM Radio InstaU 6 82 x B g screws through the two top brackets 6 82 x 3 9 screws inttresiee brackets and 6 82 x l Z screws and flat washers tlirough the bottom holee of the leather case Replace the switch lever the knobs andthe N M 4Vt PICTORIAL 8 ...

Page 29: ... to place the Radio near a window of the vehicle for best reception because the metal vehicle body will act as a shield against the reception of radio signals The automobile radio anterma can be connected to either screw of the external antennaterminal strip of the FM Radio You will probably notice some distortion of the sound at maximum volume This is normal and represents the reserve of power th...

Page 30: ...g gecflon of the Ktt Bullders Guide Check the values of the parts Be sure that the proper part has been wired lnto the clrcult as shou n in the pictortal diagrams and as called out tn the wiring lngtructlons of your hi fi system I 9 It will benecessarytomakeupa dummy l oad to protect the output t r io irj o disconnect the speaker of the n ai rii ii i conne cted to a hi fi system fnis can Le ac_ co...

Page 31: ...ide of tlte cbcuit board with the metal blade of a screwdriver You must touch the blade of the screwdriver with your finger There is no shock hazard in the Radio because of the low battery voltage A weak click should be heard If not it would indicate that transistor Q9 or Q10 or I com ponent in one or both of these stages is faulty If everythtng checks out to this polnt you can then check the base...

Page 32: ...l size transistors possess very little mass or inertia a irlii u a1e 1ot subject to the shoek vibration and micro_ phontc faults of tubes rrinsi a r_ tain a heater or filament re uir rp 311 T j no power r icri l iu lti llti ine to useful audio output gecause no il r_ erated within the cabinet fonsu iif i pected from other componeits suuiecl io a terioration from heat id il f very low potential or ...

Page 33: ...of the transistor may be cause for failure The as sembly is then hermetically sealed in a pro tective case often with an inert compound to assist in conducting heat away from the as sembly The drawing shows a typical transistor assembly As mentioned before the germanium must be doped to obtain the characteristics needed for transistor action Different materials are used to produce a P or arr I Nrr...

Page 34: ...y material that permits easy passage of an electrical current C OTtffIER or MIXER Circuitry desisnedro comour e the signal from the raOio stati r witfr an oscillator signal to produce n lE i t a different frequency Se hete In most applications transistors have operating vouages applied so that the b _ ti5i un _ tion is biased in the forward _ Or iir gai_ rection and the base_collecto t io i ibi _ ...

Page 35: ...bserved however The battery must be installed exactly BASE as instructed or damage to the transistors may nECioN result Consider briefly the nature and construction of transistors The material used in the fabrication of a transistor is a so called semi conductor Germanium and silicon are two basic materials in common use today All ttre transistors in the Radio are of the germaniumtype although sil...

Page 36: ...s frequency AnIF of 10 7 mc is employed by this Radio INDUCTANCE The property of acoiltooppose any chang e m the magnitude of an electrical current flowing in it INSULATOR Any material thatdoesnotpermit easy passage of an electrical current KC Kilocycle 1 000 cycles MC Megacyele 1 000 000 cycles 1 000 kilocycles MEGOHM 1 000 000 ohms MICROFARAD A rmit of capacity Refers to 6 eGEEid size of a capac...

Page 37: ...RMER A component designedto cou pffiiffior energy from one circuit to another Construction can vary widely depending on the application but generallyconsists ofinsu lated coils of wire wound on a common form The form maybeofsheetironforpower or audic transformers or powdered iron or air for IF and RF transformerg Transformers ai e employed for one or more ofseveralreasons theyprovide coupling of s...

Page 38: ...Paeeso X RAY VIEW RESTSTORS cAPAGrroRs ...

Page 39: ...6I ALL RESIsI VALUES AiE lNo K rmo ALL RESEIMSARE I 2WAII ALL CIPACITSSIRE lN llcUNLE SPEClr Ormrcrr s posrrrv oc vdracE MEAsUREMENTs ON THE CIRCUIT BOAiD ALL VOLIACESARE MEASUREDWTH AN II MEdM IMP OANCE VTVM WITts NOSICNAL I TO 99 FM FRONT ENO PARTs r TomcRcurr BoaRo ailo cir rs PARTS l ...

Page 40: ...2Nt747 2ND IF LIN RATIO DEA t l I I I II I 2Nt274 PUSH PULL OUTPUT 2N1274 DRIVER AMF frI I Kl u_i L ...

Page 41: ...HHA rH CO 4T3A D rY THE WORLD S FINEST ELECTNONIC EQAIPMENT IN K T 595 593 ...

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