Difference between revisions of "Cobra 142 GTL"
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| − | The Cobra 142 GTL was a fully capable AM/SSB [[Citizens Band radio]] base station that competed with the Robyn 520D and the President Washington. It is considered one of the best base stations ever made during the period. Cobra made a model one step higher known as the 2000 GTL. | + | The Cobra 142 GTL was a fully capable AM/SSB [[Citizens Band radio]] base station introduced in 1977 that competed with the Robyn 520D and the President Washington. It is considered one of the best base stations ever made during the period. Cobra made a model one step higher known as the 2000 GTL. The Cobra 2000 GTL uses a dual conversion receiver on AM and a single conversion on sideband. The 142 GTL uses a single conversion receiver on both AM and sideband. It is easier to turn up the power on the 142 GTL than it is on the 2000 GTL. The 142 GTL also has the MB-8719 PLL already installed. The 2000 GTL ha a built-in frequency counter. |
[[File:Cobra142GTLmodified640.jpg]] | [[File:Cobra142GTLmodified640.jpg]] | ||
| − | == Channels Expanded == | + | == Modification == |
| + | |||
| + | === Channels Expanded === | ||
A channels expansion modification was often installed, wired to the noise limiter switch. This left the noise limiter unusable, however, disguised the modification of the radio so non-licensed operators could avoid attracting attention. | A channels expansion modification was often installed, wired to the noise limiter switch. This left the noise limiter unusable, however, disguised the modification of the radio so non-licensed operators could avoid attracting attention. | ||
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A properly licensed HAM operator could find that this radio is a suitable SSB 10-meter rig with excellent sound. | A properly licensed HAM operator could find that this radio is a suitable SSB 10-meter rig with excellent sound. | ||
| − | == | + | === Power Modification === |
| + | |||
| + | There is a variable voltage potentiometer on the power supply that will allow varying the voltage up to 16 volts. It is set at the factory for 13.8 volts. It can be tuned up to 14.8 volts to will allow for more output power without damaging the radio. | ||
| + | |||
| + | * capable of 18 watts peak power | ||
| + | |||
| + | === Frequency Counter === | ||
| + | |||
| + | Add a "constant readout" frequency counter externally such as the Land Matic LM-260. | ||
| + | |||
| + | [[File:LM260freqcnt.jpg]] | ||
| + | |||
| + | It is also known that people have installed an internal frequency counter in place of where the front speaker resides. An external speaker can be used. Here is a picture of a good clean mod where someone added a frequency counter to the front. | ||
| + | |||
| + | [[File:Cobra142GTLwFreqCntMod.jpg]] | ||
| + | |||
| + | ==other facts== | ||
| + | |||
| + | These CB Radios all use the same Uniden Main Board | ||
| + | * Cobra 142 GTL, | ||
| + | * Radioshack Realistic Navaho TRC-490 | ||
| + | * Teaberry Stalker XX | ||
| + | * Uniden Washington (''Not the President Washington''.) | ||
| − | |||
[[Category:Electronics]] | [[Category:Electronics]] | ||
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[[Category:2-Way Radio]] | [[Category:2-Way Radio]] | ||
[[Category:Tangible Product]] | [[Category:Tangible Product]] | ||
| + | [[Category:FCC Part 95]] | ||
Latest revision as of 10:29, 28 April 2024
The Cobra 142 GTL was a fully capable AM/SSB Citizens Band radio base station introduced in 1977 that competed with the Robyn 520D and the President Washington. It is considered one of the best base stations ever made during the period. Cobra made a model one step higher known as the 2000 GTL. The Cobra 2000 GTL uses a dual conversion receiver on AM and a single conversion on sideband. The 142 GTL uses a single conversion receiver on both AM and sideband. It is easier to turn up the power on the 142 GTL than it is on the 2000 GTL. The 142 GTL also has the MB-8719 PLL already installed. The 2000 GTL ha a built-in frequency counter.
Contents
Modification
Channels Expanded
A channels expansion modification was often installed, wired to the noise limiter switch. This left the noise limiter unusable, however, disguised the modification of the radio so non-licensed operators could avoid attracting attention.
A properly licensed HAM operator could find that this radio is a suitable SSB 10-meter rig with excellent sound.
Power Modification
There is a variable voltage potentiometer on the power supply that will allow varying the voltage up to 16 volts. It is set at the factory for 13.8 volts. It can be tuned up to 14.8 volts to will allow for more output power without damaging the radio.
- capable of 18 watts peak power
Frequency Counter
Add a "constant readout" frequency counter externally such as the Land Matic LM-260.
It is also known that people have installed an internal frequency counter in place of where the front speaker resides. An external speaker can be used. Here is a picture of a good clean mod where someone added a frequency counter to the front.
other facts
These CB Radios all use the same Uniden Main Board
- Cobra 142 GTL,
- Radioshack Realistic Navaho TRC-490
- Teaberry Stalker XX
- Uniden Washington (Not the President Washington.)
