Railfan Technology > radio shack pro 79 scanner issues

my radio shack scanner is working very poorly today, i had to change 4 depleted batteries out and put 4 charged rechargables in. I am supposed to have a working scanner but my scanner is stuck on 160.860, won’t scan for trains and is STUCK ON CHANNEL 1! I also scan 161.070 but my scanner is unable to do that

I NEED SOME HELP!

nick

Posted from iPhone

it says “scan” AND “manual” instead of saying “scan” OR “manual”

only scan OR manual are supposed to be on during normal scanner function

Posted from iPhone

Is there a reset button on this model of scanner?  Then reprogram it?

Also was there any corrosion on the battery terminals from the old batteries.  The corrosion could lower the full voltage on the new batteries.

-Ken

Agree, the first thing to look at is the batteries, I have seen rechargeables having a lower voltage and causing troubles with the older electronics. Any corrosion would make it worse. There was a time when they simply required fresh batteries and did not have rechargeables.

Easy check would be to find an AC adapter or simply put in fresh standard batteries. Did a quick search and found some info on this radio on the web, didn't really check into it though.

Next fix would be declare victory on the older scanner and find a new one. I've had good luck with simply buying a well chosen second hand scanner off of EBay, in my case it had been in somebodies desk for decades. Otherwise join the BearCat 125 crowd for a hundred bucks or so.

chessie7602 Wrote:
-------------------------------------------------------
> Also was there any corrosion on the battery
> terminals from the old batteries.  The corrosion
> could lower the full voltage on the new
> batteries.
>
> -Ken

Third that, and second TCnR.

I have a Pro 92 scanner, which had the corroded battery issue. Luckily, it still works most of the time after I cleaned the terminals. In the process of cleaning, the metal contact tabs lost its original shape/springiness, so occasionally, the scanner turns off when subject to vibration.

In more severe cases, battery corrosion propagates onto the circuit board, which can lead to irratic behaving, or broken scanner. Corrosion is usually due to acid leak, which explains the "propagation."

A little gentle scraping with a pocket knife can often remove battery terminal corrosion.  I also will sparingly apply spray electronic contact cleaner.  I will repeat my admonition about Uniden portable scanners, including the BC-125AT--DO NOT CHARGE RECHARGEABLE BATTERIES IN THE RADIO.  The charging circuits are prone to malfunction and, if they do, they can overcharge and overheat the batteries, often causing irreparable damage to the radio.  I nearly lost my BC-125AT to that problem when it was only a year or so old.  I caught it in time to be repairable, but another hour on the charger and the radio would have been ruined.  I ALWAYS pull the batteries out of the radio to charge them (doing that just now as I write this).



Edited 4 time(s). Last edit at 02/12/23 09:42 by WW.

Don't clean fouled battery terminals with anything abrasive, because it destroys the plating.  Once the plating is gone, you'll have reoccuring problems with the battery connections.  A Q-tip dipped in white vinegar will eat off the leaky battery residue.  Dab on the vinegar a few time over the course of several minutes and gently scrub the terminals.  Once they are clean, neutralize the acid with spray contact cleaner, like DeoxIT R5.

And rechargeables are not forever plus the usual advice, don't set the scanner on the side for months with batteries installed.

Bob

Posted from Android

robj Wrote:
-------------------------------------------------------
> And rechargeables are not forever plus the usual
> advice, don't set the scanner on the side for
> months with batteries installed.
>
> Bob
>
> Posted from Android

That sort of depends on the rechargeable battery type.  NiCads can actually last a pretty long time, but they will develop "memory" over time and not accept a full charge.  Lithium-ion batteries are not as prone to develop memory, but will only last for a fixed number of recharge cycles.  I used to manage nearly 75 portable radios with lithium ion rechargeable batteries in my former work. We always marked the "in service" date on the batteries.  Nearly all the radios were recharged nightly.  I could usually predict to the nearest month when the lithium-ion batteries would fail, based on the in-service date, typically around 500-600 recharge cycles.  Also, both types of batteries will lose capacity in cold temperatures, with lithium ions more prone to this.   As with anything else, battery quality and life can vary with the manufacturer of the batteries, and, yes, most all of them now are made in Communist China, no matter whose brand name is on the battery.  

it may have been insufficient current, my scanner seems to be working again but now i need to see if it actually picks up any transmissions

nick

Posted from iPhone

I have another problem, a key icon has shown up on my scanner and won’t let me scan the channels for THE TRENTON LINE! It is a key icon just to the left of “BANK” which are the banks the scanner channels are on. Not allowed to scan above channels 1-7 but can scan 8-20

why that scanner issue?

nick

Posted from iPhone

the issue was fixed, went to pro 79 manual and eventually found how to turn off the key icon. Apparently i had keylock on by accident and turned it off by holding down that button for 3 seconds

nick

Posted from iPhone

Suggest using the local Weather broadcast to verify the radio is functioning. There's a number of possible channels just above 162 MHz that should be /  could be easy to find. Makes comparisons easier.

When all else fails.....