HH-70 | RV-4 | |
7 PLUS | VR4 or CUT D8 | L11, L12, L13 |
10 PLUS | VR4 or CUT D8 | L11, L12, L13 |
18 LTD | CUT D13 or CUT R84 | L7, L6, L5 |
18 PLUS | CUT D12 | L 7 |
18 RV | RV501 or CUT D502 | L304, L305, L306 |
19 | CUT D11 | L5, L8, L9 |
19 GTL | VR6 or CUT D9 | L15, L16, L17 |
19 LTD | VR6 or CUT D9 | L15, L16, L17 |
19 LTD CLASSIC | VR4 or CUT D7 | L7, L8 |
19 M | REMOVE C73 | L8, L5, L3 |
19 PLUS | RV501 or CUT C511 | L305, L306 |
19 PLUS (Plastic Case) | RV4 or CUT D8 | L11, L12, L13 |
19 XS | CUT D105 | |
20 B&K | CUT CD20 & CD21 | T11, T10, C60 |
20 LTD | CUT D13 | |
20 PLUS | RV501 or CUT C511 | L305, L306 |
20 PLUS (Plastic Case) | RV4 or CUT D8 | L11, L12, L13 |
21 | REMOVE C105 & C106 | T11, T10, C60 |
21A (Old) | CUT D24 | L9, L8 |
21 GTL | VR5 or CUT D9 | L13, L10, L9, L8 |
21 LTD | VR5 or CUT D9 | L13, L10, L9, L8 |
21 LTD CLASSIC | VR4 or CUT D7 | L7, L8 |
21 PLUS | CUT 1.5K res. next to TR34 | L12, L10 |
21 X | VR207 or CUT D212 | L212, L214 |
21 XLR | RT4 or CUT D13 | L15, L12, L11 |
23 PLUS | RV501 or CUT D502 | L304, L306, L307 |
25 GTL | VR5 or CUT D9 | L13, L10, L9, L8 |
25 LTD | VR5 or CUT D9 | L13, L10, L9, L8 |
25 LTD CLASSIC | VR5 or CUT D9 | L10, L9, L8 |
25 PLUS | CUT 1.5K res. next to TR34 | L12, L10 |
26 | CUT D24 | L7, L8 |
28 A | CUT CD28 & CD29 | T12, L2, L5 |
29 A (OLD) | CUT D24 | L7, L8 |
29XLR | VR5 or CUT D14 | L15, L12, L11 |
29 GTL | VR4 or CUT D11 | L14, L13, L12 |
29 LTD | VR4 or CUT D11 | L14, L13, L12 |
29 LTD CLASSIC | VR4 or CUT D11 | L14, L13, L12 |
29 LTD GOLD | VR4 or CUT D11 | L14, L13, L12 |
29 PLUS | CUT D20 | L12 |
31 PLUS | CUT D19 | L13, L12, L11 |
32 XLR | CUT CD11 & CD12 | L5, L3 |
33 PLUS | VR4 or CUT D17 | L11, L9 |
39 LTD (S.O.S.) | RV1 | |
40 PLUS | RV104 or CUT D203 | L305, L306 |
40 X | RV201 or CUT D203 or C215 | L304, L305, L306 |
41 PLUS | VR4 or CUT D21 | L19, L20, L21 |
45 XLR | VR105 or CUT D119 | L113, L109 |
46 XLR | VR105 or CUT D119 | L113, L109 |
47 XLR | VR105 or CUT D119 | L113, L109 |
50 XLR | VR5 or CUT D119 | L109 |
55 XLR | VR5 or CUT D119 | L109 |
62 XLR | VR3 or REMOVE C67 | L16, L15, L12 |
63 GTL | VR3 or CUT D11 | L11, L10, L9 |
66 GTL | VR2 or CUT D4 | L14, L15, L17 |
66 LTD | CUT R54 | |
67 LTD | RV4 or CUT D212 | L306, L307, L308 |
77 X | VR207 or CUT D212 | L211, L212, L214 |
78 X | VR6 or CUT D9 | L11, L12, L15 |
85 | REMOVE Q17 | L3, T4 |
86 XLR | CUT CD9 | L3 |
CAM 89 | ADD 1K res. in series with C110 | L13, L12, L9 |
87 GTL | VR6 or CUT D16 | L17, L16, L13 |
89 GTL | VR6 or CUT D16 | L17, L16, L13 |
89 XLR | VR5 or CUT D14 | L15, L12, L11 |
90 LTD | VR201 or CUT D203 | L304, L305, L306 |
93LTD WX | VR-3 | L16, L17, L18 |
132 (OLD) | CUT Q25 | T14, T15, L3, C116, (ssb) R136 |
132 A | CUT CD39 & CD40 | R79 (ssb) R87 |
132 XLR | R134 or CUT R125 | L3, (ssb)R130 |
134 | CUT D40 & D41 | L8, L10 (ssb)VR15 |
135 (OLD) | CUT Q25 | T14, T15, L3, C116 (ssb)R136 |
135 XLR | R134 or CUT R125 | L3, (ssb)R130 |
138 A (OLD) | CUT D40 & D41 | L8, L10 (ssb) VR15 |
138 XLR | VR7 or VR6 | VR8, (ssb)CT7 |
139 | VR12 or CUT D63 | L12, L10, (ssb)VR15 |
139 XLR | VR7 & VR6 | VR8, (ssb)CT7 |
140 GTL | CUT R104 | VR6, (ssb)VR7 |
142 GTL | CUT R104 | VR6, (ssb)VR7 |
146 GTL | VR5 or CUT TR29 | VR10, (ssb)VR6 |
148 GTL | CUT R131 | VR10, (ssb)VR11 |
148 GTL-DX (early prod. model) | VR5 | VR11, (ssb)VR7 |
148 GTL-DX (late prod. model) | REMOVE VR14 or CUT TR32 | VR13, (ssb)VR12 |
148 GTL-B | VR14 | RV15, (ssb)RV13 |
148 GTL-DX (copy ver.) | RV12 | RV11, (ssb)RV6,RV3 |
1000 GTL | VR6 or CUT D16 | L17, L16, L13, (ssb) |
2000 GTL | CUT R131 | VR10, (ssb)VR11 |
GTL 150 | RV14 | RV13, (ssb)RV12,RV4 |
2000 GTL,2010 | CUT TR24 Change R126 to a 2.2k resistor Change R124 to a 4.7k resistor Tune L47,L48,L46,L45,L38 for max RF output AM Carrier Power VR10 Mod Meter VR7 AM Signal meter VR1 |
142GTL | CUT TR32 Change R99 to a 2.2k resistor Change R94 to a 2.2k resistor Adjust L36,L37 for max RF output AM Power VR6 SSB Power VR7 VR1 "S"Meter VR2 Squelch VR3 TX Freq VR12 Mod Meter VR10 TX Power Meter |
148GTL+F | CUT TR24 Change R126 to a 2.2k resistor Change R124 to a 2.2k resistor Tune L37,L38 for max RF output |
29GTL/LTD/CLASSIC | CUT D11 Adjust L17,,L20,L21,L16{Some Models},L14 for max RF output Modification: Change stock final to a 2SC1969 Change stock driver to a 2SC1957,{some model use a 2SC2028 rf driver}Remove it Change R123 to a 0.47 ohm resistor Change R58 to a 2.7 ohm resistor Put a jumper across D8{by audio transformer} Change C71 to a 33uf 16volt polarized electrolytic capacitor Put a 47pf disc cap across C57 Put a 47pf disc cap across R55 For a higher dead key place a 100pf disc cap across C62{by rf driver} Key radio and say HEEELLLOOOOOO while adjusting L17,L20,L121,L16,L14 Some models dead key 8-10 watts swing 40-50PEP VR1 rx gain VR2 rx signal meter VR3 squelch VR4 AMC VR5 tx power meter VR6 antenna warning light |
25GTL/LTD/CLASSIC | CUT D9 Change R76 to a 1k resistor Change R43 to a 2.7 ohm resistor Change R108 to a .47 ohm resistor Adjust L10,L9,L8 for max RF output Modification: Change stock final to a 2SC1969 Put a jumper across the D10 diode that connects from VR5 to audio transformer{pc trace side} Adjust L10,L9,L8 again Change C91 to a 33uf 16volt polarized electrolytic capacitor | Cobra 18RV, 23 Plus | Change R505 (3.3k) to a 1k, Change R310 (2.7Ohm) to a .47Ohm, Retune L305, L306 | Cobra 90LTD | Cut D203, Change R320 (5.6Ohm) to a 1 Ohm, Change C335 (100pf-NPO) to a 150pf-NPO, retune L304,L305,L306 |