Pro 96 / AC adaptor problems anyone?

[ps630]

Sometimes when I hold the scanner with the adaptor attached- the scanner seems to shut off and reset. Anyone else have this problem? Any remedy?I am using the RS 300 mA 9 V adaptor. It usually happens when pressure is put on the adaptaplug.

 

[serebin]

Could be that you're using the wrong adapter. You should be using adapter C if I'm not mistaken. Someone else please confirm.

 

[james32746]

Sometimes when I hold the scanner with the adaptor attached- the scanner seems to shut off and reset. Anyone else have this problem? Any remedy?I am using the RS 300 mA 9 V adaptor. It usually happens when pressure is put on the adaptaplug.

This problem happens with me as well on my PRO-95 using the same plug and adaptor.

 

[loumaag]

First, "C" is the correct plug if you are using the new ones (white). If you are using the older models (black) then you need the "B" plug. Apparently RS changed the specs slightly when changing mfgrs.

Second, this has been discussed before, unlike the prior GRE models that RS had (or the Uniden's) this model has a different circuit in it in regards to the Power Plug. First, if you recharge your batteries (yellow pack) through the radio, or listen to the radio on AC while the rechargable battery pack is in it, you will note that the radio will get uncomfortably warm, I don't know about you but that doesn't seem right. When I discovered that, I quit using an adapter altogether and just recharge my NMH batteries in a rapid charger. Secondly when you unplug or plug the adapter in, the radio reboots, this also can't be good for the radio. I had to hunt up the adapter out of my junk pile just to see if it was a "C" to answer the first question.

My advice, quit using the radio on AC at all, and just get a few sets of batteries. 2100mAh NMH batteries will last about 10 to 12 hours (depending on audio), I have my radio on about 12 hours a day and change the batteries every other day unless it gets real busy then... well you get the idea.

Hope this helps.

 

[BobWeb]

<snip>

My advice, quit using the radio on AC at all, and just get a few sets of batteries. 2100mAh NMH batteries will last about 10 to 12 hours (depending on audio), I have my radio on about 12 hours a day and change the batteries every other day unless it gets real busy then... well you get the idea.

Hope this helps.

That's exactly what I do. Just get a fast charger and 8 batteries. You can then alternate between the two battery holders so you always have the next ready to go.

 

[serebin]

Secondly when you unplug or plug the adapter in, the radio reboots, this also can't be good for the radio. ...

My advice, quit using the radio on AC at all, and just get a few sets of batteries.

First off, shut your scanner before plugging in your AC cord. This is bad that you're not doing this. Have you heard of a power surge before? Well, this can't be good for the scanner if you're sending so much power in to it while it is on that it shuts itself off. Turn the scanner off, plug in AC, turn it on.

Now that we got that taken care of, there is nothing wrong with units getting warm. Have you ever had a handie talkie? Things get warm, especially batteries that have been or are being charged. There is a difference between too hot and warm.

Cheers

 

[DonS]

Secondly when you unplug or plug the adapter in, the radio reboots, this also can't be good for the radio. ...

Well, this can't be good for the scanner if you're sending so much power in to it while it is on that it shuts itself off.

The scanner "reboots" only because of the design and internal connection of the power jack. As you insert the plug, the battery ground is mechanically disconnected before the plug's tip makes contact. This is nearly the same as turning the radio off, plugging in the external DC supply, then turning the radio back on - it just happens very quickly. (One possible difference would be the fact that the unloaded DC supply likely isn't down at 9V, and you're pumping maybe 12V into certain parts of the radio. However, you have this problem even if you use the radio's power switch - with the switch in the OFF position, there is almost no load on the external supply.)

This design is also why a "loose" plug tip can cause intermittent power loss, even with batteries installed: by "wiggling" a loose plug, you're breaking the +9 connection on the tip, which also turns off the ground connection from the batteries (on the yellow battery pack, the "extra" ground tab is switched on/off by the external 9V).

 

[loumaag]

Secondly when you unplug or plug the adapter in, the radio reboots, this also can't be good for the radio. ...

My advice, quit using the radio on AC at all, and just get a few sets of batteries.

First off, shut your scanner before plugging in your AC cord. This is bad that you're not doing this. Have you heard of a power surge before? Well, this can't be good for the scanner if you're sending so much power in to it while it is on that it shuts itself off. Turn the scanner off, plug in AC, turn it on.

Now that we got that taken care of, there is nothing wrong with units getting warm. Have you ever had a handie talkie? Things get warm, especially batteries that have been or are being charged. There is a difference between too hot and warm.

Cheers

Hmmm, the bad part about cutting quotes is that you often move the focus of a post. Please note, as I stated in the actual post you quote, I had to go find the adapter in the junk box, because I don't use it at all anymore. As to the warming, yes I have handie talkie's. Several of them, that is why I characterized the warming on the Pro-96 as uncomfortable (you may read that as too warm). The only radio I have that shows anything close to this degree of heat is my Icom IC-W32A which only warms up like that if I am doing a lot (read that as too much) transmitting, never on charging.

I have two Pro-92's and my son has a Pro-95, all of these radios have NMH batteries in them, and for the most part, my Pro-92's stay plugged in on the charger 24/7 (unless I grab them to go somewhere) and my son leaves his on the charger in a like manner. None of these radios (or batteries) ever show any of the symptoms the Pro-96 does after being on a charger for an hour (excessive heat). Remember, the Pro-96 is powered by a nominal 6v power and yet the external power supply input specification is for 9v DC. The extra 3v has to go somewhere, my guess is in heat.

I will repeat my advice to anyone who actually owns a Pro-96, quit using the external power and switch to only using battery power. Somewhere down the road somebody is going to discover whatever is wrong with the actual charging circuit in the Pro-96 and then this advice will be vindicated.

The scanner "reboots" only because of the design and internal connection of the power jack. As you insert the plug, the battery ground is mechanically disconnected before the plug's tip makes contact.

Don, is this so different from the Pro-92 or Pro-95 plug design? These do not exhibit this “shutdown” when you plug or unplug external power. My opinion is you hit the nail on the head when you referred to the inrush of power. Even at 9 volts (which a 9v adapter exceeds on a "no load" situation) that is 3 volts more than the radio is powered by.

 

[serebin]

I'd get your pro-96 looked at. Mine doesn't get hot at all. I have to really try and feel the rechargeable batteries inside to feel a tiny bit of warmth. If yours is weird and not under warranty though, I'd probably just use the battery pack for non-rechargeable batteries so it wouldn't charge them while the AC is plugged in. I don't think there's anything wrong with this radio's charging abilities, but ditching AC all together is a bit weird.

My advice about turning the radio off still stands. Most instruction on portables say to turn the radio off before plugging AC in for this reason. If thats not the case for the pro-96, I still like doing it because when I have plugged in the AC without turning it off, it sometimes just shuts off completely, and doesn't turn back on again, so I'd have to turn it off and on and anyway. I dunno about you, but when it shuts off and doesn't come on again even though the power is on, it doesn't seem like a good thing to do. When I turn the radio on regularly by moving the switch, it always turns on. So something different is going on when you just stick the AC in without shutting it off. Whether or not it's substantial or not, I dunno, I'd rather just keep this scanner operational as long as possible.

ps630, I hope you found your answer some where in these posts

 

[DonS]

The scanner "reboots" only because of the design and internal connection of the power jack. As you insert the plug, the battery ground is mechanically disconnected before the plug's tip makes contact.

Don, is this so different from the Pro-92 or Pro-95 plug design? These do not exhibit this “shutdown” when you plug or unplug external power.

Mine do. My PRO-92, 93, 95, 96, and 99 all do the same thing. According to the schematics and an examination of the parts used, at least the 93, 95, and 96 should do this (I don't have schematics for the 92 or 99).

My opinion is you hit the nail on the head when you referred to the inrush of power. Even at 9 volts (which a 9v adapter exceeds on a "no load" situation) that is 3 volts more than the radio is powered by.

Dissipated as heat by the voltage regulator. Even running from batteries, there will be some heat there. The main 3.5V regulator (AN77035SP) is rated at an operating supply voltage of 14V (absolute maximum 30V) and can dissipate 5W. You won't hurt it by giving it 8.2V (after the diode), drawing 150mA or so, and dissipating the "extra" power as heat. Even if you gave it its maximum of 14V and were drawing 200mA, you'd still be well within its maximum rating.

The only time I've noticed my radios getting "hot" (or warm, whatever), is when I used to charge NiMH cells in them. That's to be expected. The charging circuit in these scanners is pretty rudimentary - just a current limiter - so the batteries will get warm. When I've powered the radio from an external supply with no batteries (or batteries in the black holder), I've not noticed any extra heat.

If your radio(s) get warm with no batteries, and if they don't power-cycle when you plug in external power, there might be something wrong with them - perhaps a broken or defective power jack.

Incidentally - my PRO-96 is quite happy running from an external 6V DC supply. I'd expect this, as after the diode drop there is still 5.2V going to the regulator. This exceeds what a fully-charged set of NiMH cells will supply.

I have noticed that if I am running from batteries and very quickly insert a "hot" 9V supply, the radio will sometimes power cycle but won't "come back up". This is probably caused by it not shutting completely down (running off of a couple of caps), but suffering a "brown out" condition - throwing the CPU or DSP off into oblivion. I highly doubt that this will physically harm the radio in any way.

From an examination of the schematic, I can't see any harm in attaching a "hot", halfway-decent 9VDC supply while the radio is powered-on, using the black battery holder. If the power switch is OFF, the supply is essentially unloaded. Turning the power switch to ON sends a (briefly) unloaded supply voltage through the radio. This isn't any different from plugging in the supply while the power switch is ON.

-Don

 

[pro92b]

Just to add to the confusion, the power supply and charging circuit is exactly the same in the PRO-93, PRO-95, and PRO-96. The PRO-96 itself draws more current than the others. In all three cases the radios dissipate a bit more heat when operating on AC. The battery is charged at 150 mA using a constant current source in each radio. From the circuitry there does not appear to be an obvious reason why the the PRO-96 should be much hotter than the others when charging the battery.

 

[loumaag]

Don,

You know, in the past you have provided some excellent advice (once you get past the basics advice) and this last post is right on target again. You may have hit the nail on the head. I gave up on NiCd batteries long ago as I got tired of them dying so quick (my fault entirely). I have been using NMH exclusively for a pretty long time now. I even rebuilt the battery pack for my Pro-90 with them. So, since in the past, I was allowing the AC adapter to charge the NMH batt's in the radio, this is probably the reason for the heat. What bothered me is that after a while the radio just got really warm. My theory (unsupported by having the schematics available) was that there was no "float" circuit in the radio. Once the batteries got charged, they just kept getting charged and this bothered me.

I too have experienced the "dies--will not reboot" problem with the Pro-96 which requires actually shuting the radio off and turning it back on to get it to function. This, along with the heat, is the reason I gave up using an adapter on the Pro-96. I haven't really run the radio on AC without the "yellow" battery holder, so maybe I will give that a try. (Perhaps serebin has a point about not abandoning AC at all ) The thing is, those 2100mAh batteries just last so long, it hardly bothers me at all to have change them once a day or so, especially since they only take 30 min or so to charge.

Don, once again, thanks for being there...errr, here.

 

[DonS]

I haven't really run the radio on AC without the "yellow" battery holder, so maybe I will give that a try.

One caution: if your 92 and 95 do, in fact, have a problem with their power jacks (such that they don't "reboot" when you plug in external power), I wouldn't use any battery holders in them. If the battery holder's ground connection isn't severed when you insert the plug, you could inadvertently attempt to "charge" non-rechargable cells in the the black holder. Your radio would get really warm!

 

[serebin]

Gotta love those 15 minute rechargeable rayovacs.

 

[loumaag]

Gotta love those 15 minute rechargeable rayovacs.

Absolutely! :lol:
Although I use the RayOVac charger, I like the Bunny for batteries.

One caution: if your 92 and 95 do, in fact, have a problem with their power jacks (such that they don't "reboot" when you plug in external power)...

I have never had a problem with the 92's (or the 90 for that matter), they all have NMH batt's in them and as I said I will plug them in and unplug them at will (while on) and nothing ever happens. I will have to check with my son on the 95.

 

[suejives]

I'm not a pro. When I bought my Pro 96 the RS salesman gave me the 6 volt
800 mA charger. It has worked great now going on to 3 months. I have had no problems at all. My DC charger is a 9 Volt still no problem. I do shut it off when plugging either in.

 

[ScanManQSL]

Quick Simple Question... I just bought 4x 2100mAh NMH batteries few days ago. I understand from loumaag said about life span per charge.
My question is: How much time until the batteries are fully charged, If im using the RS-96 and the built in charger. ???

"loumaag" 2100mAh NMH batteries will last about 10 to 12 hours (depending on audio)

- Ben -

 

[INDY72]

First time charging: 10 - 12 hours for basic trickle charging, then it takes only a lil while to recharge... Groovy eh?

 

[Michelle0H]

Maybe rechargable batteries are the way I should go. My Pro-93 has a "loose" power jack. You can't touch the cord or it powers off and on and off and on and off and on....you get my point.

I was thinking of having the case opened up and checked out, but maybe I'll just get the batteries. Are they expensive?

 

[paul34]

My question is: How much time until the batteries are fully charged, If im using the RS-96 and the built in charger. ???

Assuming you run the batteries until the scanner won't power on, then the internal charger will take about 15-16 hours to fully recharge 2100 mAH batteries -- (2100 / 150) * 1.1 (capacity/charge rate plus about 10% that is lost through heat).

Note that NiMH batteries are exothermic during the charging process, so heat is a natural byproduct of charging. NiMH batteries are less friendly when it comes to overcharging (continuous trickle even after the batteries are charged will cook out NiMH batteries much faster than NiCd).

NiCd don't produce as much heat during charge, but both types will produce heat during overcharge (about 1W dissipated by the batteries, plus another 1/2 or so at the regulator).