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HP Forum Archive 05

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HP71B AC Adaptor/Charger ?
Message #1 Posted by CJ on 24 Feb 2001, 1:40 p.m.

Hello everyone,

Does anybody know what model AC Adaptor/Charger the 71B requires. I'm running a continuous program and batteries are going quick !

I have many HP82059B/D AC Adaptors/Chargers. I also have a HP82041A.

I tried the 82059B/D and the AC annunciator did NOT light up and it didn't work. With or without batteries in the machine. I haven't tried the 82041A and am afraid to. Being that it's output is 10V.

Right now the machine is showing BAT and I tried plugging in the 82059B/D no change. No power. No joy.

Does this thing need a special pack to be in place to be able to run on AC?

I would appreciate any help. Thank you,

Chris

      
Re: HP71B AC Adaptor/Charger ?
Message #2 Posted by Todd Garabedian on 24 Feb 2001, 6:55 p.m.,
in response to message #1 by CJ

Chris,

Some sales literature I have says the 71B is supposed to take the 82059D model AC adaptor.

I also checked my 71B manual to see what it says about AC usage. Not much help, I'm afraid.

In part, it says that the AC anunciator is "reserved for future use", so I'm not sure if the anunciator is indicative of actual AC power when it is connected.

The manual also says that "When connected to a power outlet, the HP-71 uses the batteries as a backup power supply and normally doesn't draw power from them. You won't damage the HP-71 by using the computer without batteries, but you may lose everything in memory should there be a power outage or an intermettent connection to the voltage source." (p. 271).

The manual further lists "accessories included with the HP-71B" in appendix B, but a charger is not among them. Oddly, the manual never indicates which adaptor to use!

Best of luck, Todd

            
Re: HP71B AC Adaptor/Charger ?
Message #3 Posted by Steve (Australia) on 24 Feb 2001, 10:59 p.m.,
in response to message #2 by Todd Garabedian

I've used an 82068B. This is the same as I have used with the HP41, and HP97, and most of the HP41 peripherals.

I think the 8 VAC adapter is pretty much used for everything. Well, everything that it fits anyway :-)

Note that the 82068B is the Aussie version. The US version is ummmm something else (82058D I think)

                  
Re: HP71B AC Adaptor/Charger ?
Message #4 Posted by Thibaut.be on 25 Feb 2001, 1:52 a.m.,
in response to message #3 by Steve (Australia)

Yes, I confirm : the 71B works like a charm ith a 41 adapter.

                        
Re: HP71B AC Adaptor/Charger ?
Message #5 Posted by CJ on 26 Feb 2001, 7:29 a.m.,
in response to message #4 by Thibaut.be

Thanks everyone for the help!

I tried it again with the 82059B/D without batteries and got nothing. Except memory lost.

I have a feeling that the AC recepticle doesn't even work. I don't know why it wouldn't.

It is a '89 model. Oh well I guess it's batterys for me.

I appreciate all the help.

Chris

                              
Re: HP71B AC Adaptor/Charger ?
Message #6 Posted by Steve (Australia) on 26 Feb 2001, 8:53 a.m.,
in response to message #5 by CJ

Do you know for sure that the charger is OK?

                                    
Re: HP71B AC Adaptor/Charger ?
Message #7 Posted by CJ on 26 Feb 2001, 9:34 a.m.,
in response to message #6 by Steve (Australia)

Hi Steve,

Yes I am sure THEY work. I have many of them and they charge my print,cass. and power the disp, RS232, etc.

It is strange.

I bought the thing at a ham fest for $25. The gentlemen had a pile of them. Must have been a HP sellout or Goverment lot.

Maybe these were a special item that weren't supposed to be used on AC and HP changed them? Just guessing here.

Dissapointing though. I would really like to run it on AC. Like I said I'm running a continuous program(packet station) and batteries are going quick.

Thanks for the help !

Chris

                                          
Re: HP71B AC Adaptor/Charger ?
Message #8 Posted by Reinhard Hawel (Austria) on 27 Feb 2001, 5:52 a.m.,
in response to message #7 by CJ

The AC flag (and the display symbol) is never set in HP-71 operation. I believe, it can be set with a BASIC statement (SFLAG -xx, I don't know the number yet).

The 71B works with the 41C adapters and has a voltage regulator inside, so that it should work with any AC (or DC) source, that will output abt 8VAC or a little more DC.

It might have a defunct regulator part inside. This should be easy to fix (especially, if you're a radio amateur).

Does the unit work on batteries alone?

                                                
Re: HP71B AC Adaptor/Charger ?
Message #9 Posted by CJ on 27 Feb 2001, 8:29 a.m.,
in response to message #8 by Reinhard Hawel (Austria)

Hi Reinhard,

On my QRG it says that the AC flag is -57 and it can't be set/cleared by the user.

Yes it runs fine on batteries. But I get nothing from the adaptor. batteries in or out.

I think your right about the regulator be defunct.

I have no idea what part it is or were it is on the board. Does the museum CD's have schematics of this unit?

Thanks for the help.

Chris

                                                      
HP71B AC Flag
Message #10 Posted by Philip Reagan on 8 Mar 2001, 4:06 p.m.,
in response to message #9 by CJ

I have found one instance where the AC is set. Using the HP41 Translator Pac, the AC flag is set when you enter Alpha ON mode. I guess this is one of the reserved uses.

                        
Re: HP71B AC Adaptor/Charger ?
Message #11 Posted by Reinhard Hawel (Austria) on 27 Feb 2001, 5:53 a.m.,
in response to message #4 by Thibaut.be

Mine, don't work like a charm, but at least they work like a HP-71B :-)


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