Re-tune coils L10,L9,L8 for maximum forward Power.<- THIS IS OK TO DO Replace stock final with a 2SC1969 transistor. <-NOT OK BOTH OF THESE CHANGES WILL PRODUCE OVERDRIVE IN THE PRE-DRIVER AND DRIVER STAGES, NOT GOOD! 4. THE ABOVE WILL PRODUCE DISTORTION AND MAKE THE MIC CIRCUIT HARD TO CONTROL. Change R76 (3.3k) to a 1k (near the mike socket) <-NOT OK AS IT MAKES THE MIC PICKUP TOO MUCH BACKGROUND NOISE. This is a typical example of mis-information, the resistor changes listed below will not produce more power, they will make the radio sound crappie.ġ. Cobra 2010 (Discontinued) The Cobra 2010 is Cobra’s newest and best base station ever! Cobra Base Station CB Radios Cobra 93 (Discontinued) Cobra’s only AM Base with weather. **NEW** Cobra 148 NW ST Top-of-the-line CB Radio With SoundTracker and backlit front panel Cobra 148F (Discontinued) Cobra’s top-of-the-line SSB Mobile with Frequency Counter. **NEW** Cobra 29 NW ST Deluxe AM CB Radio With SoundTracker and backlit front panel Cobra 29STWX Classic CB Weather Radio With SoundTracker Cobra 75WXST Compact/Remote Mount CB Radio With SoundTracker Cobra 148GTL ST (Discontinued) SSB Mobile with SoundTracker technology. **NEW** Cobra 25 NW ST CB Radio With SoundTracker and backlite front panel! Cobra 25STWX Classic CB Weather Radio With SoundTracker Cobra 29ST Classic CB Radio with SoundTracker Cobra 29LTD ST Night Hawk (Discontinued) Classic CB Radio with SoundTracker and backlit controls. with Soundtracker and charging jack Cobra HH38 ST This compact model includes 10 weather channels Soundtracker and charging jack Cobra HH45WXST this model is discontinued! (refurbs may be available) Mobile CB Radios Cobra 18WXST CB Weatherband Radio Cobra 19 Ultra 2 Compact Mobile CB Radio Cobra 25ST (Discontinued) Classic CB Radio With SoundTracker. Cobra HH36 ST this model is (Discontinued) Cobra HH37 ST 40 chan. Handheld CB Radios Cobra HH28 Basic low-priced 40 channel CB Cobra HH33 this model is discontinued! Cobra HH34 Basic handheld with charging jack and lighter plug. What this all boils down to is this, the radio is in my opinion now is somwhat “unstable” on sideband and I for one, would not own one! To my knowledge it could be inproved with some additional filtering and RF bypassing. The new units don’t have the MB3756 Voltage Regulator, They have decided to further cheapen the radio by doing away with it! and installed a 3 pin voltage regulator in its place with a series resistor on the 8 volt pin, on the input pin there is no voltage drop, on the output pin there is. This time is the same as the last, they can’t clarify me! So I really got concerned! After checking the oscilator frequencies I find that they change when I modulate! What the Hell! they are not supposed to change, they are supposed to be rock solid! I placed a volt meter on several test points and found that the voltage to the oscillators is changing with modulation! So I start looking for the reason for this and ran into the cause right away. Then I went to Sideband, now people say they can’t “clarify” me in, What! So I tried some others on the band with the same results, can’t clarify me! So I’m thinking maybe my oscillators are off frequency so I check them and find that they are a little off so I align them. So before doing anything else, I hooked it up to my antenna to get some radio checks, well, AM was OK, nothing to write hone about but clear and clean. I had a customer send me a 148 NW ST for peaking and tuning for better receive and transmit. Now we have this new radio, the 148 NW ST, It looks real pretty at night. Of course this is all history, they fixed that problem. watt resistors throughout the whole radio, don’t know how many radios failed in the field because of this, I had several myself that had a failure of several resistors that had previously been 1/2 watt. ![]() The first thing that happened to Cobra was that Uniden wanted to raise the price on there PC boards, Cobra did not like this so they got some other company to make there boards cheeper! The first thing that happened was that they started using 1/6 Th. Their Sideband radios such as the 146, 148 gtl and 2000 were superb, they were stable and a radio you could be proud of. Cobra has really shot themselves in the foot with this new radio, why you ask? I’m getting to that but first let me say that Cobra has been the industry leader in producing good quality CB radio’s down through the years, there was the great line of Mobil “AM” radios such as the 25LTD, 29LTD. This page is for informational/educational use only and comprised of archival URL information with back links.
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