Search found 228 matches

by frogman296
Saturday 7th Mar 2009, 15:43
Forum: CB Radio Alignments
Topic: Magnum S9 PCB layout(bottom view)
Replies: 1
Views: 2273

Magnum S9 PCB layout(bottom view)

i am in dire need of a magnum s9 pcb layout, bottom view(solder side)...

help would be much appreciated... have to bring this hack job back to life

thanks in advance guys
by frogman296
Thursday 5th Mar 2009, 12:11
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

checked the others... added correct values.... still no luck... i went back to the unlocked clarifier...

radio works A+
by frogman296
Thursday 5th Mar 2009, 2:53
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

The TX alignment issue is probably due to the original clarifier mod, check for correct component values for the resistors that are connected by VR5. On the TX side R187 should be 2.7K, R186 should be 100 Ohm, there should also be diodes in D75 and D52. On the RX side R175 should be 3.3K, R174 shou...
by frogman296
Wednesday 4th Mar 2009, 8:56
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

replaced pll

now i can align the RX on freq... but i transmit off freq.... it seems as though there is not enough adjustment to the tx freq VR 5

on a side note... when i unlocked the clarifier.... the radio will align...

looks like the pll crapped out... thanks a million Scott
by frogman296
Wednesday 4th Mar 2009, 3:20
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

Of course, no CH9.. but yes, check the path and source of the voltage feeding pin 11, if you disconnect it from the ch selector and test the ch selector side for voltage it should say whether the selector is at fault, or if there is a short circuit somewhere (it should be feeding 0V), the PLL pin w...
by frogman296
Tuesday 3rd Mar 2009, 20:18
Forum: CB Radio Repair and Troubleshooting
Topic: Uniden Washington Keys Up, No TX & No RX
Replies: 8
Views: 4995

Re: Uniden Washington Keys Up, No TX & No RX

thanks scott

much appreciated
by frogman296
Tuesday 3rd Mar 2009, 20:17
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

the radio does not have the instant channel 9 function.

so i should check pin 11 of the pll and its path through the radio??
by frogman296
Tuesday 3rd Mar 2009, 19:32
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

1. 1 1 0 1 1 1 1 2. 1 1 1 0 0 0 0 3. 1 1 1 0 0 0 1 4. 1 1 1 0 0 1 1 5. 1 1 1 0 1 0 0 6. 1 1 1 0 1 0 1 7. 1 1 1 0 1 1 0 8. 1 1 1 1 0 0 0 9. 1 1 1 1 0 0 1 10. 1 1 1 1 0 1 0 11. 1 1 1 1 0 1 1 12. 1 1 1 1 1 0 1 13. 1 1 1 1 1 1 0 14. 1 1 1 1 1 1 1 15. 1 1 0 0 0 0 0 16. 1 1 0 0 0 1 0 17. 1 1 0 0 0 1 1 18....
by frogman296
Tuesday 3rd Mar 2009, 18:41
Forum: CB Radio Repair and Troubleshooting
Topic: UNIDEN WASHINGTON, no sound(tx,rx,pa)
Replies: 37
Views: 20004

Re: UNIDEN WASHINGTON, no sound(tx,rx,pa)

bump for new info
by frogman296
Tuesday 3rd Mar 2009, 18:29
Forum: CB Radio Repair and Troubleshooting
Topic: UNIDEN WASHINGTON, no sound(tx,rx,pa)
Replies: 37
Views: 20004

Re: UNIDEN WASHINGTON, no sound(tx,rx,pa)

I think you checked IC4 instead of IC5, IC4 is the audio amp, IC5 is the MB3756 you are right IC5 rx AM USB LSB 1. 8.51 8.45 8.51 8.51 2. 12.47 12.34 12.44 12.44 3. 8.52 8.47 8.53 8.53 4. 0.00(all modes rx/tx) 5.12.47 6. 8.51 0.52 0.56 0.56 7. 0.00(all modes rx/tx) 8. 0.24 8.45 8.51 8.51
by frogman296
Tuesday 3rd Mar 2009, 18:28
Forum: CB Radio Repair and Troubleshooting
Topic: Uniden Washington Keys Up, No TX & No RX
Replies: 8
Views: 4995

Re: Uniden Washington Keys Up, No TX & No RX

The Defpom wrote:It should be an 18V Zener diode.
stripe towards the IC??
by frogman296
Tuesday 3rd Mar 2009, 18:13
Forum: CB Radio Repair and Troubleshooting
Topic: Uniden Washington Keys Up, No TX & No RX
Replies: 8
Views: 4995

Re: Uniden Washington Keys Up, No TX & No RX

The Defpom wrote:D60 is mounted between pin 2 of the MB3756 and 0V, it is on the track side of the PCB, it was a factory addition, to help protect the device, not all radios have it in place, if not add it.
so its a 1n4004 type?? or a 1n4148??

so i solder it from pin 2 to chassis ground??
by frogman296
Tuesday 3rd Mar 2009, 17:39
Forum: CB Radio Repair and Troubleshooting
Topic: UNIDEN WASHINGTON, no sound(tx,rx,pa)
Replies: 37
Views: 20004

Re: UNIDEN WASHINGTON, no sound(tx,rx,pa)

There is a capacitor near the audio amp that can short out when it is old, it kills the audio, check C107. replaced c107 and a ton of other elect caps Also what voltages are you getting on IC5 ? RX TX am TX usb TX lsb 1. 12.48 12.41 12.45 12.45 2. 6.00 5.97 5.99 5.99 3. 0.00 for all modes(rx/tx) 4....
by frogman296
Tuesday 3rd Mar 2009, 15:55
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

You may want to re-check the clarifier mod, in case it is shorting the TX and RX lines together, it sounds like the MB3756 may have failed. Make sure you connect your negative test lead to one of the metal cans on the PCB, and not the chassis, as the chassis is not a true 0V. i will recheck the cla...
by frogman296
Tuesday 3rd Mar 2009, 12:37
Forum: CB Radio Alignments
Topic: Test Points in cobra 148gtl
Replies: 6
Views: 4597

Re: Test Points in cobra 148gtl

zodiac wrote:I thought you wanted the test points for adjusting the frequency not the bias.
You should find the information your after on CBTricks under radio information.
i have since found them on the site...

thanks for the heads up though
by frogman296
Tuesday 3rd Mar 2009, 10:41
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

You need to check the binary code going into the PLL, pins 16 through to pin 10, it is likely that a solder blob is shorting a couple of pins out, causing the PLL to jump to the wrong frequency, or there is some other fault causing an incorrect binary code. So what you need to do is tell me what th...
by frogman296
Tuesday 3rd Mar 2009, 8:09
Forum: CB Radio Alignments
Topic: Test Points in cobra 148gtl
Replies: 6
Views: 4597

Re: Test Points in cobra 148gtl

thanks a bunch 1096
by frogman296
Tuesday 3rd Mar 2009, 7:45
Forum: CB Radio Repair and Troubleshooting
Topic: UNIDEN WASHINGTON, no sound(tx,rx,pa)
Replies: 37
Views: 20004

UNIDEN WASHINGTON, no sound(tx,rx,pa)

Radio Make and Model: uniden washington PCB Number: PC 385AG PLL Number: MB8719 Test gear available: multimeter, watt meter...bk2040, 1040 Symptoms: no output on any mode, no rx audio, What is working: radio lights up perfect, tx/rx light changes when keyed...no rx audio, meter does not move on rx, ...
by frogman296
Tuesday 3rd Mar 2009, 4:06
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 148GTL, only 2 channels functioning
Replies: 15
Views: 6914

Re: Cobra 148GTL, only 2 channels functioning

went through the radio.... reversed the channel mod, and clarifier is now locked. replaced the crystal with the stock crystal....changes mike plug to 4 pin powered the radio up... worked perfect... 5 minutes later..... no power output in any mode... no mike audio through talkback, and no "tx light" ...
by frogman296
Monday 2nd Mar 2009, 7:45
Forum: CB Radio Repair and Troubleshooting
Topic: Uniden Washington Keys Up, No TX & No RX
Replies: 8
Views: 4995

Re: Uniden Washington Keys Up, No TX & No RX

where the devil is d60??

i cannot for the life of me see that diode
by frogman296
Saturday 28th Feb 2009, 2:47
Forum: CB Radio Alignments
Topic: Test Points in cobra 148gtl
Replies: 6
Views: 4597

Re: Test Points in cobra 148gtl

so are these the only two that are important??

i have since found a diagram that lists em
by frogman296
Friday 27th Feb 2009, 6:46
Forum: Wanted !
Topic: Dummy Load
Replies: 5
Views: 4148

Re: Dummy Load

yes it is very easy to make... cheap and it does the trick... enjoy
by frogman296
Thursday 26th Feb 2009, 17:22
Forum: CB Radio Repair and Troubleshooting
Topic: Cobra 2000 thinks it is a scanner
Replies: 10
Views: 6522

Re: Cobra 2000 thinks it is a scanner

did you ever get this issues solved... i had one do the same thing... lower the mike gain... no more problem
by frogman296
Thursday 26th Feb 2009, 14:34
Forum: CB Radio Modifications
Topic: cobra 29ltd chrome
Replies: 3
Views: 2860

Re: cobra 29ltd chrome

hmmm you are rigged to go

you can find the full alignment on radiomodz homepage for the cobra 29..

are you looking for a tune to add some modulation and power??
by frogman296
Thursday 26th Feb 2009, 9:10
Forum: CB Radio Modifications
Topic: Cobra 148 GTL mod confusion...
Replies: 7
Views: 9908

Re: Cobra 148 GTL mod confusion...

The Defpom wrote:Personally I put a 1K series resistor on the middle leg of TR24, and change R124 and R126 to 4.7K, that increases your mod level on all modes with no ill effects.
tried this mod with great success

Go to advanced search