Uniden PC78LTW Jumpers..

[LeapFrog]

Do you have a Uniden PC78LTW?
I just got my first one, and immediately went to clipping out the jumpers I found on the solder side of the board.
I have this issue because I did not photograph the jumpers before I cut them away, thinking they where part of some mod, I never saw this on a Cobra 29 so I assumed incorrectly... Both radios are similar but not identical... I'm still a "NEWBIE" so please go easy on me for forgetting to photograph what I found when I took the covers off.

Two things:
*(A) The Jumper Configuration seen at 2:59. Is this setup back to Factory, & could you please photograph this area for me to confirm that it is the correct configuration. I know the video is blurry I will take a still image.

*(B) The Diode seen @ 3:35, is this a mod or not required?
[photo=medium]4106[/photo]

Thanks for taking a look, I know I need a proper pointing tool + tripod.
-Sam

 

[LeapFrog]

I can tell the senior members that know, and possibly have one of these want me to look @ the 29 LTD schematic and figure it out for myself, I don't blame them. After all it is on me to learn!!

 

[Robb]

Haven't worked on an AM only radio in a couple of years. But if you have the schematic for it, all you would need to do is trace it through.

 

[LeapFrog]

Haven't worked on an AM only radio in a couple of years. But if you have the schematic for it, all you would need to do is trace it through.

The 29 LTD and 78LTW have a slight difference in the board layout. The solder tracks are "neater" on the Uniden radios, plus they layed out the parts "neater" the Uniden has Jumpers where the Cobra does not.

I have to sit down and cross reference the obvious parts between both radios.
If someone can photograph the jumpers found on the solder side of the Uniden (not found on the Cobra 29)
I could verify that I resoldered everything back to factory configuration without studying and cross referencing the Cobra schematic to the Uniden layout.

I just have to sit my butt down and read + study the data I already have..

-Leap

 

[sonoma]

I have not seen one of the newer cobra 29 or uniden 78 radios. a friend of mine bought a uniden 78 at Christmas time and said it had a completely new audio chip set up and it was from Vietnam. he said it had a jumper block on the audio chip that soldered to the main board 1st then the audio chip was plugged into the jumper. he said it had some jumpers on the bottom of the board. sounds a lot like what you may have. he sold it right after he got it. so no help here for the setup. hope you can find the info you need. Uniden never puts out a schematic for their radios any more. good luck on your replacement.

 

[LeapFrog]

Well I only have jumpers near the regulator and towards the front of the radio, the main board is from 1994?! So it's not too new! I have to sit down and compare my 1995 cobra to the 1994 uniden and use the cobra schematic to confirm that I resoldered the appropriate jump point on the solder side of the pc board.
In the video I compare the two areas and see that uniden layed the components out in a "single file line" where cobra just has them "scattered" the same parts are there though!