Question about Cobra 148 GTL 120-Channels Base CB Radio
Posted by Anonymous on
Put on a different mic and see if it still happens.I am going to attempt to draw an insert so if it works follow it if it doesn't I'll explain it.
this wire is the audio on the inside of mic
-------------------------------X-------(4700ohm 1/4 w res) ----X---------
this wire is the shield
at the point marked with X take two .001 capasitors and wire them from one wire to the other. this should make your squeal go away.
Posted on Aug 23, 2014
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
SOURCE: cobra 148 gtl
First take a jumper wire and connect it to the DC Ground of the input of the radio then touch it to the TX pin on the radio if it does keyes up then its in the mic or mic cord on the end of the mic plug or where it goes into the mic cable goes up inside the mic. If the radio don't key up at all then check the main voltage regulator chip one pin will have 8 volts transmit and another pin will have 8volts recieve. If you get no switching DC voltage on the regulator then its bad and needs replacing there is also a known bad capacitor in the radio thats only 10 volts change it to 25 volts at the same capacitance.
Posted on Jan 08, 2008
SOURCE: Cobra 1000 GTL by Dynascan
This is a complicated modification. I have never done it to a 1000 GTL, but its done basically the same in all radio's.
I don't recommend doing it, especially since I am not 100% sure on how exactly to do it. I have never been in a 1000 gtl. If I had one in front of me I could tell you for sure how to do it.
If the reason for Variable power is a linear, just a swing kit in for the dead key you need, most likely 2 watts, and leave it.
Here is how to do a variable power mod. this is assuming the swing mod is done the same to this as a cobra 25/29 or uniden 68/76 etc.
If you would like to try it, here it is.
You get a TIP31 transistor, Radioshack has them.
Where you put the swing mod in the radio, which is a cap and a resistor, you put the TIP31 and cap. A 47uf cap works fine.
With the resistor facing you, and the tab in the back away, solder the cap to the transistor. the leg with the black stripe goes on the right most leg. then the other goes to the center leg of the transistor.
Solder a wire on the left most leg, long enough to reach the front of the radio. Now solder the 2 legs that don't have the wire on it, in the place where you would put the swing kit, with the black stripe on the cap facing the back of the radio usually.
Remove the wires from the RF gain and solder them together.
Now solder the wire from the transistor to the center tab.
Remove VR6 and solder a wire from the top tag of the RF gain to the top connection of VR6 that you removed.
Then connect a wire from the bottom tag to a ground point. The side of a tuning can works fine.
Take a piece of shrink tube and put it over the TIP31 so it does not ground against the heat sink, that would be bad.
This is done basically the same in all cb radio's.
Posted on May 03, 2009
Hi and welcome to FixYa,
Initially, the speaker of course has been checked?
Offhand, would partial schematic of the mic and speaker section help?
Good luck and thank you for asking FixYa.
Posted on Dec 20, 2009
Tips for a great answer:
Apr 10, 2015 | Cobra Radio Communications
Apr 30, 2014 | Cobra Radio Communications
Nov 30, 2013 | Radio Communications
Nov 21, 2013 | Cobra Radio Communications
Nov 15, 2010 | Cobra 148 GTL 120-Channels Base CB Radio
Dec 18, 2009 | Cobra Radio Communications
72 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: