Cobra 148F GTL

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EZ CHOPPER
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Cobra 148F GTL

#388065

Post by EZ CHOPPER »

Anyone know how to put variable power in a Cobra 148F GTL Please let me know thanks. I guess picked this up is it a good radio ?
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Re: Cobra 148F GTL

#388071

Post by sonoma »

I have one also Chopper. I did the npc mod to mine. it dead keys 2 watts and swing all the way to the max. only way I know how to put variable in the 148 radio is to pull the vr and run wires to the locations the VR was hooked to and put them on an external out the radio variable control like the mic gain and rf gain control. maybe some one else knows another way.
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Re: Cobra 148F GTL

#388108

Post by EZ CHOPPER »

witch VR
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Re: Cobra 148F GTL

#388110

Post by sonoma »

vr10 is the control for dead key . this is the one most guys will put an external vr in the radio and run the wires to the spots the vr 10 came out of.
I do not put a variable in a single final radio.for the 148 version radio I put the npc mod in it. you can turn the dead key down to 1 1/2 watts to 2 watts and the mod will give you full swing to the radio on AM. just dropping the dead to 2 watts to run a amp will actually lower the swing also. just depends on what you want to drop the dead key for.
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Re: Cobra 148F GTL

#388116

Post by EZ CHOPPER »

Ok ill check it out way shouldn't you put variable in a single final radio never hard that
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Re: Cobra 148F GTL

#388117

Post by sonoma »

a single final is rated for a 4 watt dead key and will swing to about 18 at BEST. you can drop the dead key to about 1 1/2 to 2 watts and still swing to 18 . a dual final will swing a lot more. this is just me. never did figure out why some of the radios with a single final the factory put a variable in them other than some people want it. some say they want a low dead key for a amp. if the radio is set up right it will dead key 2 watts for a amp and still swing the full amount.
the only person that will know you have a low dead key is you. the receiving radios will never know you have a low or high dead key.
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Re: Cobra 148F GTL

#388122

Post by EZ CHOPPER »

Gotcha
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Re: Cobra 148F GTL

#388142

Post by EZ CHOPPER »

I took the adjuster out put a 50k pot in it now it will go from 1/2 watt to 5 watts its working great
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Re: Cobra 148F GTL

#388145

Post by MDYoungblood »

I think a 10K would be better. Did you get a dual pot and replace the RF gain with it?

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Re: Cobra 148F GTL

#388165

Post by EZ CHOPPER »

Ok now I have a bigger problem I took this radio and put it in another base unit case everything went well I hade to cut the stem on the ssb pot so I could put the knob back on it cause it was sticking to far out, now my frequency counter is going crazy and the radio is not working. Does anyone now where there is a diagram on this pot so I can bypass the wirings so I can use it on AM till I find a new pot or a wiring diagram on the hole pot. MAN I'm so upset about this I've been working on this thing for 2 days was doing great till I cut that thing.
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Re: Cobra 148F GTL

#388166

Post by sonoma »

not sure just what you did. tried reading it a few times. not sure what you are calling the SSB pot. any way here is some info for the radio.

http://www.cbtricks.com/radio ... /index.htm
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Re: Cobra 148F GTL

#388173

Post by EZ CHOPPER »

sorry was tired last night its the switch that changes it to am to lsb to usb
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Re: Cobra 148F GTL

#388174

Post by sonoma »

that makes since now. if you check voltage to the switch the in wire will have about 8 volts going in to the switch. then the switch will put the 8 volts to one wire at a time for am, LSB then USB. just tie the 8 volts to the wire that feeds AM to get it back to working for AM.
should be 4 wires going to the switch. just find the voltage into the switch then see witch wire will turn on the AM mode.
here is all the info from the Cobra web site. maybe this will help you.

http://downloads.cobra.com/CB ... 48-SERIES/
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Re: Cobra 148F GTL

#388196

Post by EZ CHOPPER »

going out there here just a few mins ill check that out
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Re: Cobra 148F GTL

#388201

Post by EZ CHOPPER »

finger it out it was the power supply it will read 14.5 and as soon as I turn the radio on goes to 5.6 has to be the power supply I took it out of a cobra 2000. I checked all the grounds cant find nothing so it has to be that.
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Re: Cobra 148F GTL

#388207

Post by sonoma »

5.6 volts does not make the radio work as it should. sounds like you may have found your problem
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Re: Cobra 148F GTL

#388215

Post by EZ CHOPPER »

That wasn't the problem I really find it this time.The variable power I made for it was touching the case was shorting out it working like a champ now I should have looked a little harder.
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