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From a bit of a look at your last post, I noticed some voltages you mentioned on pins you do not need to be testing, all PLL inputs are on pins 17 though to pin 9 (17,16,15,14,13,12,11,10,9), pin 7 is the phase detector output (the output of the PLL which controls the VCO to give you your final ...

Rick,

At times on Band (E) when changing channels the LED will indicate the desired change but the actual channel will not change.

Here is the requested data...on band (E) PLL chip.

Channel 37
Pin 17 = 0
Pin 16 = 0
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 1
Pin 11 = 0
Pin 10 = 0

Channel 38
Pin ...

Rick,

Finally found time to continue. Here are the code(s) for Band (E) PLL chip

Channel 1
Pin 17 = 1
Pin 16 = 1
Pin 15 = 0
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

Channel 2
Pin 17 = 0
Pin 16 = 0
Pin 15 = 1
Pin 14 = 1
Pin 13 = 1
Pin 12 = 0
Pin 11 = 1
Pin 10 = 0

Channel 3
Pin 17 ...

I located the code's....what procedure would I use to evaluate as they are numeric?

EDITED: I think I now understand what you are asking, as the code is binary, an depending on a returned voltage it would indicated a (0) or (1). So if I am on the right tract all you would need are the voltages from ...

Not good news.......I used the pin out information for MC145106P, so I believe I got that right. Thanks, for sticking with me on this, you have been a great help. I will check the wiring tomorrow, got to go to work.

Here are the updated values...sorry for the mess-up, I learned that not all grounds are equal.



Ch. 1 --------- Ch. 2 --------- Ch. 3 ---------- Ch. 19

Pin 10 = 0v --Pin 10 = 0v -- Pin 10 = 0v -- Pin 10 = 0v
Pin 11 = 7.8v Pin 11 = 7.7v Pin 11 = 7.7v Pin 11 = 7.6v
Pin 12 = 0v -- Pin 12 = 0v --Pin ...

Your right........I was using a chassis ground. Using a can the voltage reads higher, I will retake the readings. Power supply is 13.8v

It maybe a bad PLL chip, but before you go down that road. Let check some thinks out, the PLL works in binary you do not need to understand this all you need to do is give me voltages at Pins 10 to 17, and if you can write them like so

Pin 10 = 0v
Pin 11 = 8V
And so on

If you can do 4 channels ...

Check the voltage at TP2 on channel 1 and channel 40 on the CB band this is band (D) or (E), let us know what voltage you have?

Is the RX/TX LED changing colour when you key-up?
Red in TX and Green in RX.

What channel is the radio stuck on?

Has any one been in the radio and been playing with any ...

Check the voltage while change channel at Pins 10 to 17 on the PLL chip (IC5) you should see the voltage change from 0 to 8 volts depending on which channel you are on. If the voltage does not change then check the voltage while change channel at Pins 1, 3, 5, and 7 of (IC1) you should see the ...

I have a DX 44V EPI360014B board. After warm-up I can change channels, which is reflexed in the channel display, but the actual channel stays where it was at...anyone had a similiar problem or a fix?

What ever happened to this radio. I have look for a source, but could not find any. Did it make the FCC most wanted list?

hello,i have fixed those by just reheating the solder joints.but like they say most times you have to completly replace it..if you dont have a new one,try to find a junk radio,that they work in,and use it.

Reheating would definitely be worth a try....I located a 29 chassis that was destroyed by ...

Thanks, nomadradio...for the walk through and information. I've got a vacuum type de-solder pen, and a couple of old pc boards to practice on, as you are correct I have as yet to work on a pc solder connection. The ratshack would be easier to work with, and the price is right. My hobby is restoring ...

Rick wrote:9 times out of 10 its a faulty LED display, so the easy way is to just replace it.

Thanks Rick, I did find a reference here[/url]http://www.radiomods.co.nz/forum/viewto ... hlight=can you help?

nomadradio wrote:Uhh, "Lights" ?

Have never seen an on-line walkthrough of that project. Both digits are in one piece of plastic. If one segment on one digit goes dark, there's no way to fix it, but to replace the entire 2-digit display.

73

I have this very problem can you provide the link?

I have a Cobra 29 LTD Classic, with the LCD channel display only partially lite. I have the repair manual but it does not mention anything about the display. Can anyone provide any suggestions to trouble shoot or replace, such as just the LCD or the entire board?