Black vs. Yellow Battery Trays...

[MacombMonitor]

Most of the Radio Shack hand-helds now come with both black, and yellow battery trays. The black being for Alkaline, or non-rechargables, and the yellow being for rechargables. Is the difference only related to the function of recharging, or does the yellow one also compensate for the lower voltage of the rechargables? Alkalines being 1.5v x 4 = 6v, and most recharables being 1.2v x 4 = 4.8v.

Thanks!

 

[rdale]

"Is the difference only related to the function of recharging"

Yes

 

[jf222]

The yellow (recharge) holder has an extra prong that connects to the recharge circuit - the black one has only two for power - use the yellow one only if you intend to recharge batteries in the radio - use the black one for non-recharge batteries or if you recharge with an external charger.

 

[MacombMonitor]

The yellow (recharge) holder has an extra prong that connects to the recharge circuit - the black one has only two for power - use the yellow one only if you intend to recharge batteries in the radio - use the black one for non-recharge batteries or if you recharge with an external charger.

Ok, I understand that. I guess what I'm trying to confirm is can I use both trays with recharables, as long as I do not intend on charging the batteries in the radio? I change the batteries in a seperate, dedicated fast charger. But I would like to have both trays loaded, so it's quicker to swap out in the radio.

From a performance perspective, how does the radio itself tell the difference between the batteries and compensate for the voltage drop of the rechargables, without impacting performance? I was thinking possibly that extra contact also disabled a voltage dropping resistor, or some type of voltage regulator circuit.

 

[OkRob]

Ok, I understand that. I guess what I'm trying to confirm is can I use both trays with recharables, as long as I do not intend on charging the batteries in the radio? I change the batteries in a seperate, dedicated fast charger. But I would like to have both trays loaded, so it's quicker to swap out in the radio.

Bill, Yes, you can use your rechargable batteries in the black case in the radio with no problems, you just won't be able to charge them in the radio in that case. Since you're using a free-standing charger, you can charge them up in that charger and then use them in either case in the radio, but will only be able to charge them via the radio circuit in the yellow case.

- Rob

 

[MacombMonitor]

Thanks guys!

 

[BaLa]

I got both of them loaded up with 4 Rayovac IC3s.
Works great.

 

[MacombMonitor]

I got both of them loaded up with 4 Rayovac IC3s.
Works great.

That's exactly what I'm doing! You're right...works great!

 

[Al42]

From a performance perspective, how does the radio itself tell the difference between the batteries and compensate for the voltage drop of the rechargables, without impacting performance? I was thinking possibly that extra contact also disabled a voltage dropping resistor, or some type of voltage regulator circuit.

No. The radio works on 7.2 volts just as well as it works on 9 volts (with the exception that the maximum available audio is higher with higher voltage). But fully charged NiMH batteries will give you about 8.46 volts, so there's not that much difference.

 

[Voyager]

The yellow (recharge) holder has an extra prong that connects to the recharge circuit - the black one has only two for power - use the yellow one only if you intend to recharge batteries in the radio - use the black one for non-recharge batteries or if you recharge with an external charger.

There is a triad of danger on the PRO-96. You MUST AVOID ANY ONE of the following:

1. Use Alkaline cells
2. Use the YELLOW holders
3. Power the scanner with an external source

IOW, if you avoid #1 (don't use alkalines), you can use the black or yellow holders and/or power the scanner externally (note that using the black will not charge the cells)

If you avoid #2 (don't use the yellow holder), you can use rechargable or alkaline cells and/or power the scanner externally

If you avoid #3 (don't power the scanner externally), you can use rechargable or Alkaline cells and use either holder.

What you can never do, and this is the ONLY thing that will get you in trouble, is do all three at the same time. NEVER use external power with the yellow holder with Alkalines. (#3 + #2 + #1 = BAD)

Me? I charge my cells externally (avoiding #3), so I can use either holder with any type cells. Contrary the quoted statement, you can use the yellow holder with alkalines (as long as you don't use external power).

But, if you want to avoid two sides of the triad, all the better.

Joe M.

 

[Air490]

I have only ever used the yellow holder once and found that it discharged a fully charged set of NiMH batteries. The batteries were Energizer 2500mAh batteries, all of which were quite new.

They were put in the scanner (a Pro-97) in the morning. The scanner was then turned off and left till about 10am. When i was turned on the batteries lasted all of about 3 minutes.

I have never had this problem when using the black holder with NiMH batteries.

 

[winkydo]

I have only ever used the yellow holder once and found that it discharged a fully charged set of NiMH batteries. The batteries were Energizer 2500mAh batteries, all of which were quite new.

They were put in the scanner (a Pro-97) in the morning. The scanner was then turned off and left till about 10am. When i was turned on the batteries lasted all of about 3 minutes.

I have never had this problem when using the black holder with NiMH batteries.

thats interesting. anyone else seen this problem? the third prong on the yellow adapter should only be the charging ciruit.

my question is will we see any performance increase using a solid 9volt wall outlet over the rechargable batteries that have been running a few hours?

also, will the batteries charge faster in the scanner with the radio off or on? i know on some electronics it does not matter, on others, its perfered you turn the unit off to charge the batteries.

where's our ratshack electricians?

 

[Al42]

I have only ever used the yellow holder once and found that it discharged a fully charged set of NiMH batteries. The batteries were Energizer 2500mAh batteries, all of which were quite new.

Sounds like a defective Pro-95. There's a leakage path between the charge contact on the battery holder and ground.

my question is will we see any performance increase using a solid 9volt wall outlet over the rechargable batteries that have been running a few hours?

Most likely not. The radio will start complaining about weak batteries before there's any performance hit (other than increased audio distortion at high levels).

also, will the batteries charge faster in the scanner with the radio off or on? i know on some electronics it does not matter, on others, its perfered you turn the unit off to charge the batteries.

That depends on the charging circuit and the current available from the external power source. If you power a Pro-95 from a 9 volt, 240 mA or more supply, the batteries will probably charge just as fast with the scanner on or off. If you power it from a 9 volt, (greater than 90 mA but less than 240 mA) supply, it'll take longer to charge if the scanner is on. (The scanner takes 90 mA, the charger takes 150 mA.)

 

[loumaag]

To: Al32:

Looking over your posts in this thread causes confusion. I want to know how you get this out of 4 batteries:

But fully charged NiMH batteries will give you about 8.46 volts, so there's not that much difference.

I mean I realize that 1.2 volts is a nominal figure for NiMH batteries, but where do you get cells that store better than 2 volts each?

This is also confusing:

The radio works on 7.2 volts just as well as it works on 9 volts ...

The radios discussed in this thread all operate on between ~3.25 and ~ 6 volts. Where do you get 7.2? Unless you are talking about external power which is dropped in the radio's charging circuit.

 

[Al42]

To: Al32:

Looking over your posts in this thread causes confusion. I want to know how you get this out of 4 batteries:I mean I realize that 1.2 volts is a nominal figure for NiMH batteries, but where do you get cells that store better than 2 volts each?

I got that out of 6 cells, because 1) I was thinking of an older scanner I used to own, 2) the scanner uses 9 volts for external power and 3) I didn't look at the battery holder before I posted <sheepish grin>. Make it 5.64 volts (1.41/cell). That makes it: very little difference between 5.64 volts and 6 volts. (I would assume - or does the radio itself use the full 9 volts if it's available? I don't have a schematic.)

 

[loumaag]

I got that out of 6 cells, because 1) I was thinking of an older scanner I used to own, 2) the scanner uses 9 volts for external power and 3) I didn't look at the battery holder before I posted <sheepish grin>. Make it 5.64 volts (1.41/cell). That makes it: very little difference between 5.64 volts and 6 volts. (I would assume - or does the radio itself use the full 9 volts if it's available? I don't have a schematic.)

:lol:
I own two of those 6 cell ones myself, still.

I do have a schematic for the Pro-96 but as usual, I can't put my hands on it right now to check (and since we are packing for the upcoming move, I doubt if I will see it again in the near future), but I do remember that there was a voltage drop in the charging circuit before passing it on to the scanner for power. The ~6 volt figure comes from considering 4 alkaline batteries.