Display question for Uniden Pro 640e

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Exit_Thirteen
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Display question for Uniden Pro 640e

Post by Exit_Thirteen »

I just recently got a new display for my Uniden Pro 640e, board #PB-105AB.

I currently have it hard-wired on the "Dim" setting (it has a Bright/Dim button) to prevent the display from burning out...should I reduce the input voltage to the display further? Or will this setting be fine for the display? Thanks in advance for any info.


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Studio1
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Post by Studio1 »

I managed to find a NOS display for my 640e a few years ago, and decided at the time to drop the LED current right back.

When I had fitted the new display and saw how bright it was, even on the low setting, I realised why the LEDs end up dying.
I can't remember how I did it, think it was just a resistor or two but it shouldn't be too hard to work out.

Drop the current right back so the display is still readable on the high setting.

My set has been running with no lost segments now for a couple of years.

Uniden here told me at the time that the display module is obsolete - no longer made, and that they had no stocks of them even in Japan. I managed to get their last one.
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Post by Exit_Thirteen »

Yikes....I got lucky on my display...I'll have to see what I can do as far as reducing the current flow to the display. Thanks for the reply!


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Rick
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Re: Display question for Uniden Pro 640e

Post by Rick »

You will need to change all the resistors on the Display board.
What are the values of the ones in use?

Some of the Uniden radios which used to be imported in to the UK had 14X 270R resistors and I used to change them to 1K, but you may find any value for about 560R to 1K2 should be ok.

The higher you go in value the dimmer the display will be.
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Post by Exit_Thirteen »

Rick,

Thank you for the info, I'll look into it and let you know how I get on. One of my friends is using the radio at this time, I'll get it from him and take care of it soon.



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"You need to adjust that sideband. You're sounding a little daffy." -John "the 395" (Cobra Kid)
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