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200 GTL DX - 'Pinched' SSB audio adjustments

- If the SSB audio is muffled and narrow, or 'pinched up' sounding an adjustment of the carrier point may be necessary in order to correct this. The output quality of the SSB audio frequency response is greatly improved by adjusting (T714 - LSB) and ...

Hi at all;I have in my shop 9 Cobras 200GTL-DX with the TX power problem in the Hi Position.I founded the problem."A bad Driver transistor".The driver part number is #RD16HHF1.I make a call at the Cobra service department,because this part does not have any replacement.The original Cobra part ...

I just bought a new Cobra 200. It works great on the high band. Swr 1.3. When I hit my amp swr 1.4-5. The problem is this drives my amp too hard(about 750 to 800 watts). When I hit the amp on low power with about 8 watts the swr goes out the roof but will modulate backwards to 1.8-2.4. The swr on ...

Cobra 200 GTL DX has a 2 year warranty.
I would send it back to them for repair.
The turn around time is usually not too long.

peace,

haans

Hi John,

We are working on the pinched SSB audio on the Cobra 200 GTL DX now. We are also somewhat dissatisfied with the SSB audio quality considering this is a Cobra radio. I first believe the power cable is underrated for the output of the radio PA section. I changed mine to 8 guage wire from the ...

No, the mod does not cause the problem you are experiencing.

1.) You need to key the TX in AM/FM mode, or CW (Carrier Modes).

2.) Turn the calibrate knob clockwise until it reaches the cal mark on the upper right of the meter with the radio in TX mode.

3.) Then depress the button and switch from ...

Usually a transverter is used in such a case.
Such as the Ten-Tec kit
These units use 20 meters (14 Mhz), 2 meters (144 Mhz) & 10 meters (28 Mhz) as the input frequencies. But, not all of them transvert to 6 meters. Some are 2 meter transverters.

http://radio.tentec.com/kits/Transverter


I hope ...

I agree it's TOTALLY STUPID to do something like this, BUT that's the MENTALITY of CB operators especially the NEWBIES. What a joke, the FCC sould have never gotten rid of cb-licensing and they should make people take a test on how to use a cb-radio and proper ettiquette. 73 Jim :x

Well Jim, I ...

What about moving R138 to R619's empty slot?

http://ham-radio.mine.nu/cobra200gtl_freq_conversion.jpg

1.
Remove power from the radio.
2.
Remove the covers and locate the TMP87PP21DF Microprocessor near the front right of the unit.
3.
Locate and Remove the surface mount Resistor R138 to the left ...

Let's cover a few topics on this to dispell any myths

The 2SC2290 transistor is capable of 60 Watts.
You could "dead key" an AM carrier with this much power but, there would be no room left to modulate it. Depending upon whether it's high or low level modulation in the 200GTL DX. If it is High ...