#1
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Radio Shack PRO-2030 80 channel scanner does not power up
I dont know which forum to put this in .The Mods can place it in the right forum if you like.Thanks
Hi all.I have a PRO-2030 80 channel scanner that does not power up. It has 12 volts going to Q14 2SB1187 transistor.There is no power getting to the 5 volt regulator "IC6" with the heatsink. The unit has digital power button .Its not like standard power on and off switch. It worked fine the night before .The next day it wont power up. I have no service manual or diagram to go further fixing it. Thanks in advance for any info on this scanner. |
#2
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No power to the regulator? Seems like it should. Is the power supposed to be switched to the reg? Maybe an open circuit trace from unreg V to the input of the 5V regulator? If it runs hot enough for a heat sink maybe a cracked solder joint? Just guessing.
Seems RS scanner schematics are tough to come by. I have a Pro-2050 Trunk Tracker that stopped receiving after a power outage. It appears to be working and scanning but receives zero signals. Never have found a schematic for it. I guess they are still afraid we users will modify them to receive 800 mHz cellular signals, even though analog FM cellular has been obsolete for years! |
#3
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Thanks Ed .I will check the traces .Everything is cold where the 12volts are going through.I like to know how and what switches the power on.
The next step is to pull out the 2SB1187 and test it.The 5 volt regulator checked fine after I pulled it and tested it. Yes I agree The 800 band thing is over.What they are worried about and they are going under anyway. |
#4
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With the momentary contact Power button it probably has to have a standby +5V (?) going to the syscon IC, and that would probably have an output that turns on the rest of it. Just guessing! All my RS scanners, I have several, 2050, 2041, 2039, have a power switch on the volume control.
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#5
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Thats how I figured it out.The digital switching runs through the syscon chip on the display frontend.
Tonight I played around with it and pulled the power transistor in question out and test it. Its the culprit.So I did some cross referencing back and forth with some spare transistors I had in my spare parts collection. I found a transistor close and a bit more on the power ratings and installed it. Whalaa it fired up. I checked the voltages and they look OK.Since I dont have the service manual so I cant determine if they are right on the money. I'll run it for a few hours and feel for heat and let it do the burn in test to make sure it works OK. Since this scanner was my late stepfathers which made it a sentimental value .It made it more special to get it up and running. Thanks Ed for your input. |
Audiokarma |
#6
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Congratulations! That deserves two thumbs up!
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#7
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Thanks Ed.Today I reprogrammed the freqs back in the memory .
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