Schematic

LogicData TA-9 Calculator: Reverse-Engineered Schematic

Schematic of the LogicData TA-9 pocket calculator of 1972 with a fluorescent display.

Author: Brent Hilpert
Type: Schematic
Credit: Drawn and written by Brent Hilpert, Early Electronic Calculators, madrona.ca.

R12 22K Q7 TIS93 BATLOW R8 R11 2.74K Q5 Q6 200 TIS92 TIS92 D13 R9 R10 1N5221B 3.92K [notinstalled] 2.4V D5 D1::4 1N5235A 4•1N914 6.8V C3 C4 wh 22µ R5 22µ V–6 R1 15V 470 10V wh 1.2 Q3 bk C2 wh TIS93 R3 100p whrd C1 1K Q1 bk R2 AC AC 22µ TIS92 ND19 22 4• AA yl AC/CHG AC/CHG 10V MSD –23V C6 NiCd D12 OFF OFF bkwh yl ND2 ND10 10µ V–15 whbk 1N5246 BAT BAT Q2 LSD 20V 16V TIS92 rd D10 D6::9 D11 1N5256A R7 og 4•1N914 [nv] R4/1K 30V 3.3K C5 *5.6V ogwh gn 4.7µ R6 V–29 bn 50V 4.7K Q4 gn TIS93 19µS 13µS 32µS 31.250KHz Ø Ø1 Ø2 R22 C10 5µS 1.5µS 4.7K 100p R19 R20 C8 Ø1 R13 R16 10K 10K 680p ØQ 15K 22K nØ Q10 R21 TIS92 Q8 Q9 10K* R23 TIS92 R14 R17 TIS92 47 V–15 ØQ0 4.7K 4.7K 128µS V–15 V–14 V–14 R15 R18 1.8K* 5.6K* C7 Notes V–15 2•1n V–15 R25 Ø1 4.7K C9 Ø2 • This drawing based on unit with Serial No. 00218. 100p ØQ Ø Q11 • 2020 Jan: Initial drawing / bhilpert. R24 TIS92 * measured and 2020 Mar: PCB layout & component enumeration added / bh. 10K* ØQ0 assigned nearest 2024 Feb: Correction to R11/D13 ordering / bh. standard value V–15 V–15 ØQ7 LogicData TA-9 ØDn Calculator ØQn pulse is 4•Ø1 = 128µS. ØQn cycle is 8•4•Ø1 = 1024µS. Page: 1 / 3 Printed: Feb 27, 2024 Number cycle is 8•ØQn = 8.192mS = 122Hz. 1 BATLOW ND 6 21 Ø1 Ø1 NEG 14 7 18 Ø2 Ø2 ERR 9• 15 VACUUM FLOURESCENT 1 2 5 DISPLAY TUBES NK 21 32 15 K0 Ø1 Ø1 Sa 21 22 22 31 5 K1 Ø2 Ø2 Sb 20 23 each 23 3 23 K4 ØQ ØQ Sc key 19 10 27 24 16 3 K7 ØQ0 ØQ0 Sd 18 12 29 4 17 ØQ7 ØQ7 Se 0 1 4 7 5 28 16 Sf 24 25 ic1 20 22 K–N Sg 17 36 25 26 ic2 36 4 K2 Sh 16 37 26 27 ic3 37 1 K5 Sp 15 38 15 28 ic4 38 adef g K8 14 39 ic5 39 a a –N 2 5 8 40 ic6 40 f b f b 2 g g 29 ic7 33 h h KP 13 9 e c e c 30 ic8 34 K3 U1 U2 12 11 d p d p 31 [t.u.] ic9 18 [t.u.] K6 11 13 32 K9 10 n.c.: 8 n.c.: 21, 35 R26::34 DP 3 6 9 9•470K 20 30 ØDS C11 6 33 4.7µ 14 K+ ØD7 9 10V 7 34 V–6 K– 8 13 20 ØD6 K* 8 7 19 12 K÷ ØD5 6 9 + – ÷ 11 ØD4 10 18 9 K=K ØD3 5 11 17 KM 8 4 ØD2 16 12 KT 3 7 35 ØD1 KC 13 2 6 =K M T C ØD0 14 4 3 19 17 V–29 NK22 V–6 V–15 V–6 V–15 V–6 LogicData TA-9 Calculator Page: 2 / 3 Printed: Feb 27, 2024 CHG– BAT– R13 15K Q8 R25 4.7K R23 47 Ø GND R2 22 R16 22K 1 Sp C10 100p 1 R22 4.7K 2 FIL Q10 1 GND U2 ic6 40 1 GND U1 ic5 40 2 C GND R1 1.2 C7 2n 3 Sd Ø1 2 GND ic5 39 2 ic6 ic4 39 3 T R20 10K 4 Sh C8 680p 3 ØQ ic4 38 3 V–15 ic3 38 4 M Q9 C6 10µ D12 16V 5 Sb R19 10K 4 ØQ7 ic3 37 4 V–6 ic2 37 5 =K R8 2.74K R9 3.92K nØ R7 3.3K 6 ØD0 C9 100p 5 GND ic2 36 5 ØQ7 ic1 36 6 ÷ 7 ØD1 R21 10K Q11 6 ØDS - 35 6 Ø1 KC 35 7 * R6 4.7K Q7 Q5 R5 470 8 ØD2 R14 4.7K 7 ØD7 ic8 34 7 Ø2 K– 34 8 – C5 4.7µ C3 22µ Ø2 R15 1.8K D10 30V R12 22K R10 nkK D5 6.8V 9 ØD3 8 ØD6 ic7 33 8 - K+ 33 9 + R18 5.6K D6::9 D1::4 10 FCT 9 ØD5 Ø1 32 9 ic7 K9 32 10 9 R17 4.7K D Q6 D 11 ØD4 10 ØD4 Ø2 31 10 ØQ K6 31 11 6 R24 10K D D 12 ØD5 11 ØD3 cap 30 11 ic8 K3 30 12 3 D R11 200 D13 2.4V D 13 ØD6 12 ØD2 Sd 29 12 ØQ0 KP 29 13 P 14 ØD7 13 ØD1 Se 28 13 ic9 K8 28 14 8 15 Sa D11 5.6V 14 ØD0 Sc 27 14 NEG K5 27 15 5 16 Sf R26 470K 15 Sp Sh 26 15 ERR K2 26 16 2 Q3 17 Se 16 ØQ0 Sg 25 16 KT K–N 25 17 –N R34 470K V–6 18 ERR 17 V–15 Sf 24 17 KM K7 24 18 7 R33 470K V–29 19 FIL 18 ic9 Sb 23 18 =K K4 23 19 4 Q4 R32 470K 20 ØDS 19 V–6 Sa 22 19 K÷ K1 22 20 1 R31 470K 21 NEG 20 ic1 - 21 20 K* K0 21 21 0 R30 470K 22 Sg 22 V–6 R29 470K C4 22µ 23 Sc R28 470K C2 100p C1 22µ Q2 Q1 C11 4.7µ R27 470K R3 1K R4 1K PCB Component-side View E B Display Tubes C bottom view front c g p d Grid LogicData TA-9 Fil Fil Calculator e h f b a Page: 3 / 3 Printed: Feb 27, 2024