Author Topic: Radio Shack Pocket Repeat  (Read 1929 times)

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Offline muffenmeTopic starter

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Radio Shack Pocket Repeat
« on: March 03, 2017, 07:28:26 pm »
I like to change 3 of 4 red leds with yellow, green and blue of the same size.  Is it possible to do, the leds don't need to be bright, just lit.  Do I need to change any resistor.  Thanks
 

Offline james_s

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Re: Radio Shack Pocket Repeat
« Reply #1 on: March 03, 2017, 07:53:41 pm »
Depends on what voltage is available, red LEDs typically have the lowest forward drop, blue are one of the highest, some are close to 3V. You will probably need to change the resistors to get consistent brightness between colors but you might not care. Try it and see what happens. You can always put the original LEDs back if it doesn't work well.
 

Offline Rick Law

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Re: Radio Shack Pocket Repeat
« Reply #2 on: March 05, 2017, 06:27:47 pm »
And... if brightness equality is important, it is probably easiest if you using one of those 25 turn trim pots to help with determining the resistance.

I used to do it mathematically to give different color led the same current.  But, same current != same brightness.

Now I use a trimpot to get them to appear equally bright, then use a DMM to find out what resistance it is.  Then I do some quick calculation to make sure that is within the LED's spec.  If all is well, I find a fix resistor closest to the measured value and then solder it in.
 

Offline Alex Eisenhut

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Re: Radio Shack Pocket Repeat
« Reply #3 on: March 06, 2017, 12:16:50 am »
Haven't seen one of these in a long time. I used to play with one as a kid when it was rainy at the summer place. There wasn't much else to do in the pre-net days, except for the two local TV channels on the BW TV...
Hoarder of 8-bit Commodore relics and 1960s Tektronix 500-series stuff. Unconventional interior decorator.
 
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Offline muffenmeTopic starter

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Re: Radio Shack Pocket Repeat
« Reply #4 on: September 04, 2022, 02:56:01 am »
I did replaced the LED and it did work. My unit now has the right color LEDs instead of all just red LEDs.
 

Offline james_s

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Re: Radio Shack Pocket Repeat
« Reply #5 on: September 04, 2022, 06:41:48 pm »
I'd never heard of the Pocket Repeat but it looks like a clone of Simon. I have both an original full sized and a pocket Simon, I like that they use incandescent lamps.
 

Online ebastler

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Re: Radio Shack Pocket Repeat
« Reply #6 on: September 07, 2022, 05:29:27 am »
I did replaced the LED and it did work. My unit now has the right color LEDs instead of all just red LEDs.

It took you a while to replace those LEDs, but thanks for the follow-up post!  ;)
 


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