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johndavidsonjd
06-20-2017, 06:33 PM
Hello all
New here just jumped on
Looking for some help
I just bought a used cobra from a local bc shop
All I really wanted was regular 40 plus USB and LSB
Well now that I have it it seems it's been modded
High /low and bright/dim switch throws you into other channels...
I'm assuming this is an "extra channels"?
I know all the "rules" about these extra channels
What I want to know is since there is no frequency readout
How do I know what frequency I'm on? Anyone know? I've googled it all day and can't find anything but instructions on how to do this but not what the outcome is...
Any help would be greatly appreciated!


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222DBFL
06-21-2017, 10:50 PM
Normally when extra channels are added, a frequency map is also provided. If not you'll need to get a decent frequency counter as like you are asking, you won't know which frequency you are on without either a channel/frequency chart or a frequency counter hooked to to the radio. What radio did you get? A cobra 148gtl?? Or something else. The 148gtl is the one with SSB. If it's a cobra 29 modded for extra channels, you won't have SSB. But I am sure you know that.
All that aside, you truly need a road map for the frequencies, or have a frequency counter installed or install one yourself or buy one that will work as a stand alone unit and doesn't have to be wired into the radio. There are options l, but they can get expensive. Just some food for thought. Maybe ask the person you bought the radio from if he by chance has a map or frequency chart for the extra channels/frequencies. JMHO's. Hope you get it resolved. Good day.

halfwatt959
06-22-2017, 09:45 AM
My suggestion is get an inline frq counter. there are a few out there in the 40 -50 dollar range that will do nicely. However the cheap ones only show either the TX frq or the RX frq, you would have to get models to check that it is tracking right. but either one will let you know where you're at. I have a dosy FC-50 not sure where I got it but was about 40 bucks.just screw a jumper from the radio to the in side and the ant, watt, swr meter ect. to the side that says out. actualy a great investment. ranger makes/ sells one called the FC347 that plugs in a jack on the back of export ranger type radios. I belive they are also under $60. They read RX and TX frq but would have to hard wired into your radio. I don't have the wireing info but may can find for you. What flavor cobra did you get?

irish
06-22-2017, 09:57 AM
http://www.longcom.ie/cb_frequencies.aspx
have a look here for the frequencies in question your starting point will be ch 19 hit the switches until your hear some truckers 27 185 ch 19

johndavidsonjd
06-22-2017, 10:40 AM
Thanks guys
Yeah it's a cobra 148 gtl
I've found several road maps online
Both switches down are standard 40 bc channels
Looks like the pattern you put those switches in put you lower or upper
Gonna take it to a shop and see if they can make me a road map
If not get a counter


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halfwatt959
06-22-2017, 11:58 AM
The problem with online "maps" is ya don't know who did the mod or what they put on which switch. My best and cheapest answer would be a shop with a frq. counter. However they are real handy to have especialy for SSB. good luck

Redbeard
08-18-2018, 10:40 PM
Have the same set up on mine. Real confusing. This what I found online at Anglefire.
CHANNEL TWEAKS:
EASY TWEAK: Install EXPO 100 kit "B".
Or
1. Replace 11.1125 crystal with an 11.3258 crystal.
2. Isolate the ground pin 10 of the MB8719 PLL by cutting the PC trace.
3. At this point, turn your radio on and check to verify that all channelsare locked in and working. If it is not, adjust these in the following order:
a. CT3 for USB.
b. L20 for LSB.
c. L19 for AM.
4. Install a SPST switch between pins 11 and 12 of the MB8719 PLL
5. Install a SPST switch across the cut you made to isolate pin 10.
CHANELLS:
SW1 / SW2 DOWN (NB/ANL-LOW-DIM): NORMAL 1-40
SW1 UP / SW2 DOWN (NB/ANL-HI-DIM): (ch.15-27) 26.815 to 26.955
SW1 UP / SW2 UP (ANL-HI-BRT):
1= 27.605 6= 27.505 11= 27.565 20= 27.525
2= 27.455 7= 27.515 12= 27.585 23= 27.575
3= 27.465 8= 27.535 13= 27.595
4= 27.485 9= 27.545 14= 27.605
5= 27.495 10= 27.555 16= 27.475
SW1 DOWN / SW2 UP (NB/ANL-LOW-BRT): (Ch. 1-40) 27.605 to 28.045

Mastertech11
02-27-2019, 02:32 PM
Cheap frq. counter can be had on ebay for 10 bucks or so, they work great. I can print a case for them