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Old school Cobra 148GTL....

Oatmeal

Active Member
Mar 22, 2009
484
78
38
West Virginia..
I found one of these Philippine made radios, this one has the mic jack on the side as you no, and someone put a 6 position knob/switch beside the mic jack, there for extra channels, so have no road map as to what channels is what, and no frequency counter, 1st question, how can I find whats, what with these extra channels ?...

And too, noticed as you key the mic the needle on the radio goes over to the plus before the 30, what does this indicate ?....

No idea if this radio has anything else done to it besides the channel mod, old as it is, it probably has been peaked in the past, the guy I got it from is a ham operator, so guessing he has set everything back to normal, except for the channel kit, don't no just guessing....been away from the cb thing for a long time and don't think I ever had a radio that the needle went over this far....
 

... 6 position knob/switch beside the mic jack, there for extra channels, so have no road map as to what channels is what, .
Common mod for a radio with the MB8719 PLL. Talk to Mr Google and ask; mb8719 6 position switch



EDIT: You can also download Master Mod manual #6, go to p.22 and look for the frequency map on the Cobra 148 (using stock crystal) with a 6 position rotary. See link below;

https://www.worldwidedx.com/threads/cb-radio-service-manuals.141889/page-2#post-629322

 
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it all depends on how he modded the radio. there are more than one version to get extra channels so with out a freq counter it may be hard to get what you have right. there is 4 versions of the channel mod for this radio. off hand I do not have them all around me. most mods only take you down to 26.815. there is one to drop you below this plus one to get you the ones just above 27.405. the one mod will give you 27.415 to about 27.455. just loading what channels come to memory for the last ones.
 
Actually this radio has a 4 position knob on the side and has the regular channel in the 3rd position on it, never seen one setup like this, the expo channel kits always had mine put on a knob on the radio, where you moved it to the left for lower channels, and center was normal channels and to the right was higher channels...
This is just different from what I had, should be fun, lol....
 
A glance at the solder side of the circuit board under the PLL chip will reveal if this is the 'chip' mod, rather than a crystal kit like the Expo 100.

The typical setup for that radio was to use the PA/CB and Tone High/Low switches. This gave you four sets of channels, including the normal 40. There's a lot of overlap this way, but it's cheap to do.

An operator who wanted to preserve the front-panel switches can still wire that same setup to a rotary switch. Same hookup, just a different switch.

Wires soldered to pins 10 and 11 of the PLL leading to the switch will tell you that it was expanded this way.

73
 
Good morning, thanks guys for the info....

I haven't pulled the cover off to look inside it, been long time since I fooled with cb, what i see in this radio as u key the mic the needle n side the radio goes up to a 30, been long time since I fooled with a cb, but this don't seem right....

I may need to find a good tech and send it out to be looked at, since none are around here these days...
 

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