Pro 95 won't turn on

[rsparkyc]

years ago i had a pro 32 that had the pin connectors between the boards.
aften many years the corrode and i would put the radio on its back and perform radio "CPR" by tapping the front and it would come back to life. i knew if i took it apart and put them together a couple of times it should work and eventually i got time to do it and it worked.
i still think yours is the power connection at the switch by what you said.
but try putting them back together and see what happens.

Yeah, I've taken it apart multiple times, and have even looked for weak solder joints and haven't found anything.

gmclam, I don't have a PRO-95. Can you please verify that the (+) power goes to the center of the connector? Thanks! rsparkyc, please take your meter and verify that you have 9v DC with (+) on the center of the connector of the AC power adapter. It wouldn't surprise me to see excessive voltage or polarity reversed on the adapter.

@tvengr Literally just tried that to be sure! But yeah, polarity looks correct (otherwise the meter would be showing negative voltage). I doubt (but maybe) that the .23 volts would be considered too excessive.

 

[rsparkyc]

And if it's helpful, the voltage between ground and the positive "charing" port when it's all put together and plugged in is 9.03 volts, which seems like it would be good.

EDIT: That's actually not true, it's closer to the 9.23 volts, I just didn't have a good connection with the multimeter.

 

[tvengr]

9.23 volts is well within the acceptable range.

 

[rsparkyc]

For fun, I tried another experiment where I put my multimeter inline between 2 of the battery connections to force current to run through the meter. I then looked for current flow when I turned it on, but also got nothing .

 

[tvengr]

How did you insert the meter? One of the battery connections must stay connected to the scanner while you insert the meter between the other battery connection and the scanner.

 

[rsparkyc]

How did you insert the meter? One of the battery connections must stay connected to the scanner while you insert the meter between the other battery connection and the scanner.

It's hard to tell from the picture, but you can see I plugged one terminal of the multimeter near the negative terminal of one battery, and I hold the other terminal against the positive end of another battery. The place where I did this normally has those batteries connected in series by nature of the design of the charger (it's one piece of metal that has the spring for the negative end of one battery and the wire for the positive end of the one I'm holding.

Basically, instead of just passing through the wire built into the black battery holder, it needs to pass through the meter instead.

 

[tvengr]

From your photo, it appears that you are setup for measuring the voltage of only 2 batteries in series, not the current to the scanner. If your meter is set to current, you are putting a short across those 2 batteries and may damage your meter. You may have blown a fuse in the meter.

 

[rsparkyc]

The meter seems fine, and I think the picture didn't really do justice for what I did. I basically split the batter pack in half, inserting the meter into the "middle" of the pack. Since I inserted it where a positive end of one battery was already connected to the negative end of the next. battery in series, I didn't introduce a new short by adding the meter there.

Notice here in the battery pack those ends are normally "connected". I'm basically breaking that connection and inserting the meter so I could track what the current would be across that point.

Regardless, my scanner is still as good as a brick

 

[kb3isq]

The meter seems fine, and I think the picture didn't really do justice for what I did. I basically split the batter pack in half, inserting the meter into the "middle" of the pack. Since I inserted it where a positive end of one battery was already connected to the negative end of the next. battery in series, I didn't introduce a new short by adding the meter there.

Notice here in the battery pack those ends are normally "connected". I'm basically breaking that connection and inserting the meter so I could track what the current would be across that point.

Regardless, my scanner is still as good as a brick

lt is hard to see but at the bottom right of picture 2 there are two copper strip bands. Like I said it is hard to see but it looks like the bottom
strip band is open. I have had that happen to quite a few PRO 96 scanners. If it is simply solder a thin wire across the opening.

 

[rsparkyc]

@kb3isq I'm looking for what you're talking about, and can't seem to find what you're describing. Is it on the side of the scanner where you can see the blue blocks of the squelch and volume/power knobs, or on the other side where you can see the contacts soldered through the board?

Perhaps you could post the exact picture you're talking about, and I could take a better one?

 

[wtp]

the meter set up is good, i know what he did.
the two cells on top are connected by a wire between them @_@ across the top kind of thing.
there are 4 cells in the pack and that is how they are connected together.

 

[wtp]

or, it is time for a new radio...

 

[rsparkyc]

or, it is time for a new radio...

That’s the answer I figured we’d eventually come to (but hoped we wouldn’t). Sad, I’ve had that thing half my life.

 

[wtp]

the wife has a couple of entertainment centers with my old scanners on display, some work some don't. just an idea.
most stuff in them are antiques, like my baby shoes that are about 3 inches long, i am now over 6 feet tall and they fit in the palm of my hand.
great for laughs. there is even a motherboard from zaxxon.

 

[rsparkyc]

the wife has a couple of entertainment centers with my old scanners on display, some work some don't. just an idea.
most stuff in them are antiques, like my baby shoes that are about 3 inches long, i am now over 6 feet tall and they fit in the palm of my hand.
great for laughs. there is even a motherboard from zaxxon.

Nice. I have a buddy who’s really into electronics (even makes his own firmware for lightbulbs), so I’ll probably send it to him so he can tinker with it.

 

[lebrunmn]

@kb3isq I'm looking for what you're talking about, and can't seem to find what you're describing.

I think @kb3isq is onto something. I've also had my PRO-96 refuse to power on when I had a faulty battery holder. He's talking about the holder itself--have you tried switching out the holder?

 

[rsparkyc]

I think @kb3isq is onto something. I've also had my PRO-96 refuse to power on when I had a faulty battery holder. He's talking about the holder itself--have you tried switching out the holder?

If I’ve verified I’m getting voltage to the power switch, and I also have an external power adapter, wouldn’t that rule that out?

 

[lebrunmn]

If I’ve verified I’m getting voltage to the power switch, and I also have an external power adapter, wouldn’t that rule that out?

Well if you're going to start using logic, there's not much I can do to assist.

You're right, of course... I'm always hoping for a simple fix. Hate to see you part with an "old friend".

 

[rsparkyc]

Well if you're going to start using logic, there's not much I can do to assist.

You're right, of course... I'm always hoping for a simple fix. Hate to see you part with an "old friend".

Well, perhaps my friend will figure it out (or perhaps by some miracle someone else may chime in and say “try this”), but I doubt I’ll ever just trash it. I do plan to buy another, I’m really into aviation (actually planning flight sim right now) and love listening to aviation traffic. I also live close to both towered and untowered airports, and listening to callouts (and predicting what the next ones will be) is one of the best ways for me to learn.

 

[lebrunmn]

Good luck to you... hope you get it fixed.